NANOGRANULAR MAGNETIC FILM AND ELECTRONIC COMPONENT

Abstract

A nanogranular magnetic film includes first phases comprised of nano-domains dispersed in a second phase. The first phases include Fe and Co. The second phase includes a second phase compound including at least one selected from the group consisting of O, N, and F. A measurement range is determined in the nanogranular magnetic film. The measurement range is divided with grids including at least 80,000 grids each measuring 1 nm1 nm1 nm. Fe/(Fe+Co) and a concentration of the second phase compound of each of the grids are measured in atomic ratio. Provided that the grids are classified into MX-rich grids and MX-poor grids, a CV of Fe/(Fe+Co) of the MX-rich grids is larger than a CV of Fe/(Fe+Co) of the MX-poor grids.

Claims

1. A nanogranular magnetic film comprising: first phases comprised of nano-domains dispersed in a second phase, wherein the first phases comprise Fe and Co; the second phase comprises a second phase compound comprising at least one selected from the group consisting of O, N, and F; and a CV of Fe/(Fe+Co) of MX-rich grids is larger than a CV of Fe/(Fe+Co) of MX-poor grids, provided that a measurement range is determined in the nanogranular magnetic film, the measurement range is divided with grids comprising at least 80,000 grids each measuring 1 nm1 nm1 nm, Fe/(Fe+Co) and a concentration of the second phase compound of each of the grids are measured in atomic ratio, the grids are classified into the MX-rich grids and the MX-poor grids, the concentration of the second phase compound in the MX-rich grids is not lower than an average concentration of the second phase compound, and the concentration of the second phase compound in the MX-poor grids is lower than the average concentration of the second phase compound.

2. The nanogranular magnetic film according to claim 1, wherein a volume ratio of a volume of the first phases to a total volume of the first phases and the second phase is 40% or more and 65% or less.

3. The nanogranular magnetic film according to claim 1, wherein Fe/(Fe+Co) of the grids averages 0.15 or more and 0.85 or less.

4. An electronic component comprising the nanogranular magnetic film according to claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWING(S)

[0032] FIG. 1 is a sectional schematic view of a nanogranular magnetic film.

[0033] FIG. 2 is a sectional schematic view of a manufacturing apparatus.

[0034] FIG. 3 is a schematic view of the manufacturing apparatus.

[0035] FIG. 4 is a schematic view of the manufacturing apparatus.

DETAILED DESCRIPTION

[0036] Hereinafter, an embodiment of the present invention is described with reference to the drawings.

[0037] As shown in FIG. 1, a nanogranular magnetic film 1 according to the present embodiment has a nanogranular structure. In the nanogranular structure, first phases 11 (nano-domains) are dispersed in a second phase 12.

[0038] The nanogranular magnetic film refers to a thin film that has the above structure and includes the second phase that is not resin. Literally, a ribbon or a molded body is not a nanogranular magnetic film even if the ribbon or the molded body has a structure in which first phases 11 (nano-domains) are dispersed in a second phase 12.

[0039] The first phases 11 (nano-domains) have a nanoscale average size, i.e., an average size of 30 nm or less. The average size of the first phases 11 (nano-domains) may be 15 nm or less. Any method of measuring the sizes of the respective first phases 11 (nano-domains) may be used. For example, equivalent circle diameters of the first phases 11 (nano-domains) in a section of the nanogranular magnetic film 1 may be regarded as the sizes of the first phases 11 (nano-domains).

[0040] The equivalent circle diameters of the first phases 11 (nano-domains) in the section of the nanogranular magnetic film 1 denote the diameters of circles having the same areas as the areas of the first phases 11 (nano-domains) in the section of the nanogranular magnetic film 1.

[0041] The first phases 11 are phases containing metal elements. Specifically, the first phases 11 contain Fe and Co. The first phases 11 may contain Fe and Co in any manner. For example, the first phases 11 may contain Fe and Co at any ratio; as an alloy of Fe, Co, and other metal elements; or as a compound of Fe, Co, and other elements. A compound in the first phases 11 may be an oxide magnetic material, such as a ferrite.

[0042] The first phases 11 may have any total content of Fe and Co. The ratio of the total content of Fe and Co in the first phases 11 to the total content of Fe, Co, X1, and X2 in the first phases 11 may be 75 at % or more, 80 at % or more, 90 at % or more, or 95 at % or more. Note that, in calculation of the ratio, an element that accounts for a larger proportion of the second phase 12 than of the first phases 11 is not regarded as part of X1 or X2

[0043] X1 includes at least one metalloid element. X1 may include, for example, at least one metalloid element selected from the group consisting of B, Si, P, C, and Ge.

[0044] X2 includes at least one metal element other than Fe and Co. X2 may include, for example, at least one metal element selected from the group consisting of Nb, Mo, Cu, Ti, Zr, Cr, Mn, V, W, Al, and Ni.

[0045] The first phases 11 may contain elements other than Fe, Co, X1, and X2. The ratio of the total content of the elements other than Fe, Co, X1, and X2 to the total content of Fe, Co, X1, and X2 may be 10 at % or less or may be 5 at % or less.

[0046] The second phase 12 is a phase containing at least one non-metal element. Specifically, the second phase 12 is a phase containing at least one selected from the group consisting of O, N, and F. The second phase 12 may contain the at least one element selected from the group consisting of O, N, and F in any manner. The second phase 12 may contain the at least one element selected from the group consisting of O, N, and F as, for example, a compound (which may be referred to as second phase compound) of the at least one element and other elements. That is, the second phase 12 may contain an oxide, a nitride, an oxynitride, and/or a fluoride of any elements other than O, N, and F. The second phase 12 may contain an oxide, a nitride, and/or a fluoride of any elements other than O, N, and F. The second phase 12 may be a mixed phase of an oxide, a nitride, and/or a fluoride.

[0047] In a situation where the compound contained in the second phase 12 is an oxynitride, the ratio of the nitrogen content of the second phase 12 to the total content of oxygen and nitrogen of the second phase 12 (which may be referred to as N/(N+O) below) may exceed 0 at % and be 46 at % or less or may be 15 at % or more and 46 at % or less. Any method of measuring N/(N+O) of the second phase 12 may be used. N/(N+O) may be measured using, for example, an impulse heat melting extraction method. Note that it is difficult to use XRF. This is because it is difficult to ensure the accuracy of difficult measurement of the content of an element having a small atomic number (e.g., O or N).

[0048] The second phase compound may be of any type. Examples thereof include SiO.sub.2, Al.sub.2O.sub.3, AlN, Si.sub.3N.sub.4, MgF.sub.2, BN, MgO, GaO.sub.2, GeO.sub.2, and Si.sub.3N.sub.4.Math.Al.sub.2O.sub.3. Among these compounds, oxides may be oxynitrides having oxygen partly substituted by nitrogen. That is, the compound contained in the second phase 12 may be a Si oxynitride, an Al oxynitride, a Mg oxynitride, a Ga oxynitride, or a Ge oxynitride; or may be a Si oxynitride, an Al oxynitride, a Mg oxynitride, or a Ga oxynitride.

[0049] The nanogranular magnetic film according to the present embodiment constitutes

(Fe.sub.xCo.sub.yX1.sub.aX2.sub.b)-X3, [0050] where [0051] X1 includes at least one selected from the group consisting of B, P, C, and Ge; [0052] X2 includes at least one selected from the group consisting of Nb, Mo, Cu, Al, Ti, Zr, Cr, Mn, V, W, Al, and Ni; and [0053] X3 includes at least one selected from the group consisting of SiO.sub.2, Al.sub.2O.sub.3, AlN, Si.sub.3N.sub.4, MgF.sub.2, BN, MgO, GaO.sub.2, GeO.sub.2, Si.sub.3N.sub.4.Math.Al.sub.2O.sub.3, a Si oxynitride, an Al oxynitride, a Mg oxynitride, a Ga oxynitride, and a Ge oxynitride; and [0054] where

[00001]$\begin{array}{c}0.15x0.85,\\ 0.15y0.85,\\ 0a5.,\\ 0b10.,\mathrm{and}\\ 0.9x+y+a+b100\end{array}$

may be satisfied.

[0055] The above chemical formula shows that the composition of the first phases 11 is Fe.sub.xCo.sub.yX1.sub.aX2.sub.b in atomic ratio and that the second phase 12 constitutes X3. X3 may include at least one selected from the group consisting of SiO.sub.2, Al.sub.2O.sub.3, AlN, Si.sub.3N.sub.4, MgF.sub.2, BN, MgO, GaO.sub.2, GeO.sub.2, Si.sub.3N.sub.4.Math.Al.sub.2O.sub.3, and a Si oxynitride (SiON). The ratio of the first phases 11 to the second phase 12 in terms of volume is described later.

[0056] The nanogranular magnetic film 1 according to the present embodiment may contain, as impurities, elements that are not constituents of the first phases 11 or the second phase 12. Out of 100 at % of all elements in the nanogranular magnetic film, the nanogranular magnetic film may contain 5 at % or less impurities.

[0057] The volume ratio of the volume of the first phases 11 to the total volume of the first phases 11 and the second phase 12 is not limited. The volume ratio may be, for example, 70% or less or 65% or less. That is, V.sub.1/(V.sub.1+V.sub.2) may be 0.70 or less (70% or less) or 0.65 or less (65% or less), where V.sub.1 denotes the volume ratio of the first phases 11 and V.sub.2 denotes the volume ratio of the second phase 12. V.sub.1/(V.sub.1+V.sub.2) may be 0.60 or less (60% or less). The higher the volume ratio of the volume of the first phases 11 to the total volume of the first phases 11 and the second phase 12, the higher the Bs but lower the specific resistance.

[0058] There is no lower limit of the volume ratio of the volume of the first phases 11 to the total volume of the first phases 11 and the second phase 12. The lower limit may be 30% or more or 35% or more. That is, V.sub.1/(V.sub.1+V.sub.2) may be 0.30 or more (30% or more) or 0.35 or more (35% or more). V.sub.1/(V.sub.1+V.sub.2) may be 0.40 or more (40% or more). The lower the volume ratio of the volume of the first phases 11 to the total volume of the first phases 11 and the second phase 12, the higher the specific resistance but lower the Bs.

[0059] The first phases 11 may have a crystal structure. Specifically, the first phases 11 may have a body-centered cubic (bcc) crystal structure. With the bcc crystal structure, the saturation flux density (Bs) readily increases. Crystals in the crystal structure of the first phases may have an average crystal grain size of 1 nm or more and 30 nm or less or preferably 1.5 nm or more and 15 nm or less.

[0060] Any method of checking the crystal structure and the average crystal grain size may be used. The crystal structure can be checked using, for example, an X-ray diffraction (XRD) pattern analysis or an electron diffraction pattern analysis with a TEM or the like. The average crystal grain size can be checked from, for example, a TEM image or a STEM image. The average size of the first phases 11 (nano-domains) can be regarded as the average crystal grain size.

[0061] Any method of measuring V.sub.1/(V.sub.1+V.sub.2), which is the volume ratio of the volume of the first phases 11 to the total volume of the first phases 11 and the second phase 12, may be used. The volume ratio can be calculated from, for example, XRF measurement results of the nanogranular magnetic film 1. The volume ratio may also be calculated from the area ratio of the area of the first phases 11 to the total area of the first phases 11 and the second phase 12 through observation of a section of the nanogranular magnetic film 1 using a TEM. In this situation, the area ratio is converted into the volume ratio.

[0062] The nanogranular magnetic film 1 may include only the first phases 11 and the second phase 12, but may further include different phases other than the first phases 11 and the second phase 12. The proportion of the different phases is not limited. The different phases may account for an area ratio of 10% or less of the area of a section of the nanogranular magnetic film 1 observed with a TEM. The different phases may partly or entirely be a void.

[0063] All the first phases 11 are independent of another in FIG. 1. However, some of the first phases 11 may be connected.

[0064] The nanogranular magnetic film 1 may have any thickness. The thickness may be, for example, 50 nm or more and 200,000 nm or less. A suitable thickness may be appropriately selected according to usage. Any method of measuring the thickness of the nanogranular magnetic film 1 may be used. The thickness can be measured with, for example, a TEM, a SEM, or a surface profiler. Also, the reliability of measurement results may be checked by correlating multiple measurement apparatuses with each other in advance.

[0065] A measurement range having a volume of 80,000 nm.sup.3 or more is determined in the nanogranular magnetic film 1. This measurement range is divided with grids of at least 80,000 cubes each measuring 1 nm1 nm1 nm. For all the grids, the atomic ratio of the constituent elements is measured. Then, Fe/(Fe+Co) of all the grids and the concentration of the second phase compound of all the grids are measured in terms of atomic ratio of the constituent elements.

[0066] Grids whose concentration of the second phase compound is not lower than an average concentration of the second phase compound are classified as MX-rich grids. Grids whose concentration of the second phase compound is lower than the average concentration of the second phase compound are classified as MX-poor grids. The average concentration of the second phase compound is calculated by averaging the concentrations of the second phase compound of all the grids. The MX-rich grids are grids having a relatively high second phase compound content, i.e., grids having a relatively high second phase content. By contrast, the MX-poor grids are grids having a relatively high first phase content.

[0067] The average concentration of the second phase compound of all the grids almost matches the ratio of the second phase compound content of the nanogranular magnetic film 1 to the total content of Fe, Co, and the second phase compound in the nanogranular magnetic film 1.

[0068] The nanogranular magnetic film having a larger coefficient of variation (CV) calculated from Fe/(Fe+Co) values of the MX-rich grids than a CV calculated from Fe/(Fe+Co) values of the MX-poor grids has a higher specific resistance with respect to Bs, compared to a conventional nanogranular magnetic film having a composition and a structure similar to those of the former nanogranular magnetic film except for the CVs. That is, the nanogranular magnetic film becomes a better material as a core material of a thin film inductor. Note that a CV is a parameter calculated by dividing the standard deviation by the average.

[0069] Measurement of the above parameters can be carried out with a three-dimensional atom probe (3DAP).

[0070] Fe/(Fe+Co) of the grids may average 0.15 or more and 0.85 or less. Note that this average of Fe/(Fe+Co) of the grids almost matches the average of Fe/(Fe+Co) of the nanogranular magnetic film as a whole.

[0071] A method of manufacturing the nanogranular magnetic film according to the present embodiment is described below.

[0072] The nanogranular magnetic film according to the present embodiment is manufactured with a sputtering method using, for example, a manufacturing apparatus shown in FIGS. 2 to 4. FIG. 2 is a sectional schematic view of the manufacturing apparatus. FIG. 3 is a schematic view of the manufacturing apparatus (in particular, a rotation plate 111a and a substrate 113) viewed along the direction indicated by the arrow of line III-III shown in FIG. 2. FIG. 4 is a schematic view of the manufacturing apparatus (in particular, a shutter 131 and a sputtering target 123) viewed along the direction indicated by the arrow of line IV-IV shown in FIG. 2.

[0073] The substrate 113 on which to form the nanogranular magnetic film is fixed to the rotation plate 111a of a rotation member 111. The rotation plate 111a is fixed to a rotation axis 111b.

[0074] A substrate used as the substrate 113 on which to form the nanogranular magnetic film may be of any type. Examples of substrates include a silicon substrate, a silicon substrate having a thermal oxide film, a MgO substrate, a (non-magnetic) ferrite substrate, a sapphire substrate, a glass substrate, and a glass epoxy substrate. However, the substrate is not limited to these substrates. Any of various ceramic substrates or semiconductor substrates can be used.

[0075] On the above various substrates, constituent members (e.g., a coil or a wire) of a product or a component (e.g., thin film inductor) may be provided. For example, a substrate for a thin film inductor may be provided with a coil pattern or a wiring pattern for the thin film inductor.

[0076] Alternatively, instead of the above various substrates, foil or a sheet of metal, plastic, resin, or the like can be used as the substrate 113.

[0077] Preferred as preprocessing of the substrate 113 are a surface treatment with an UV/O.sub.3 method under normal pressure and a vacuum surface treatment (e.g., reverse sputtering, ion milling, or plasma cleaning). Because a magnetic film for a thin film inductor has a large thickness, peeling-off of the film due to stress is highly problematic. However, carrying out both of the above surface treatments greatly improves this peeling-off of the film. The amount of time of each surface treatment is not limited. The treatment time of the UV/O.sub.3 method may be, for example, 0.5 minutes or more and 60 minutes or less. In a situation where reverse sputtering is carried out as the vacuum surface treatment, the reverse sputtering time may be 0.1 minutes or more and 20 minutes or less.

[0078] The rotation plate 111a and the shutter 131 shown in FIGS. 3 and 4 may have any shapes. Their outer circumferential shape may be, for example, a perfect circle. An intersection of a dashed line C in FIG. 2 and a surface of the rotation plate 111a provided with the substrate 113 is denoted by point C. An intersection of the dashed line C in FIG. 2 and the shutter 131 is denoted by point C. Point C is a center of the rotation plate 111a having a perfectly circular outer circumference. Point C is a center of the shutter 131 having a perfectly circular outer circumference.

[0079] The sputtering target 123 is attached to a sputtering apparatus 121. The sputtering target 123 may be of any type. However, in order for the nanogranular magnetic film to readily have a larger CV calculated from the Fe/(Fe+Co) values of the MX-rich grids than a CV calculated from the Fe/(Fe+Co) values of the MX-poor grids, the sputtering target 123 is preferably a sputtering target produced by mixing and sintering Fe, Co, and the compound contained mainly in the second phase or by mixing and sintering an FeCo alloy and the compound.

[0080] Also, a chip containing a simple substance or a compound of any element other than Fe, Co, and the constituent elements of the compound contained mainly in the second phase may be appropriately placed on a surface of the sputtering target 123. Placing the chip allows the nanogranular magnetic film to contain the simple substance or the compound of any element other than Fe, Co, and the constituent elements of the compound contained mainly in the second phase. Note that, in a situation where the above method is used to let the nanogranular magnetic film contain the simple substance or the compound of any element other than Fe, Co, and the constituent elements of the compound contained mainly in the second phase, they may be contained in the first phases or the second phase.

[0081] However, in a situation where, instead of the above mixed and sintered sputtering target, a target that is produced with a sintering method or a melting method and is provided with, on its surface, an Fe chip, a Co chip, and/or a chip of the compound contained mainly in the second phase is used as the sputtering target 123, it is difficult for the CV of Fe/(Fe+Co) of the MX-rich grids to be larger than the CV of Fe/(Fe+Co) of the MX-poor grids. This reduces the specific resistance with respect to Bs. Examples of targets produced with the sintering method or the melting method include a target containing only an FeCo alloy or a target containing only the compound contained mainly in the second phase.

[0082] The sputtering apparatus 121 may be of any type that can form the nanogranular magnetic film on the substrate 113 by sputtering.

[0083] As shown in FIG. 4, the shutter 131 has a hole above the sputtering target 123.

[0084] Rotation of the rotation axis 111b rotates the rotation plate 111a for sputtering. This intermittently forms the nanogranular magnetic film on the substrate 113.

[0085] Appropriately controlling the rotation speed of the rotation plate 111a, lengths L1 to L5, and the like changes a continuous film formation time and a continuously formed film thickness of the nanogranular magnetic film. A pseudo-multilayer of the nanogranular magnetic film is thus formed. That is, repeating a film forming step and a mitigating step forms the pseudo-multilayer of the nanogranular magnetic film.

[0086] Because locations of boundaries between layers of the pseudo-multilayer cannot be actually confirmed even with a TEM or the like, pseudo- is used. With formation of the pseudo-multilayer, the nanogranular magnetic film having a larger CV of Fe/(Fe+Co) of the MX-rich grids than a CV of Fe/(Fe+Co) of the MX-poor grids is formed. This nanogranular magnetic film has an increased specific resistance with respect to Bs. Its reason is not clear; however, it is assumed that the reason is that intermittent formation of the nanogranular magnetic film mitigates stress in the nanogranular magnetic film.

[0087] The film formation time per layer of the pseudo-multilayer (which may be referred to as continuous film formation time) and the film thickness per layer of the pseudo-multilayer (which may be referred to as continuously formed film thickness) are not limited. The continuous film formation time may be 0.7 seconds or more and 5.0 seconds or less or may particularly be 3.4 seconds or less. The continuously formed film thickness may be 0.4 nm or more and 3.0 nm or less or may particularly be 2.0 nm or less. In particular, in a situation where the rotation speed is reduced to increase the continuous film formation time and the continuously formed film thickness, it is difficult for the CV of Fe/(Fe+Co) of the MX-rich grids to be larger than the CV of Fe/(Fe+Co) of the MX-poor grids. This tends to reduce the specific resistance with respect to Bs.

[0088] The sputtering atmosphere is not limited and is preferably a gas atmosphere in which 0.05% or more and 3% or less, particularly 0.2%, O.sub.2 gas is added to an inert gas (e.g., Ar gas, Kr gas, Xe gas, or Ne gas). In a situation where sputtering is carried out in an atmosphere to which the O.sub.2 gas is not sufficiently added, the CV of Fe/(Fe+Co) of the MX-rich grids tends to be smaller than the CV of Fe/(Fe+Co) of the MX-poor grids. This tends to reduce the specific resistance with respect to Bs.

[0089] The nanogranular magnetic film formed by sputtering may be subject to an annealing treatment. The annealing temperature is not limited. The annealing temperature may be about 200 C. to about 500 C. or may be 250 C. to 450 C. The annealing time is not limited. The annealing time may be about 0.1 to about 180 minutes.

[0090] Any method of measuring magnetic properties of the resulting nanogranular magnetic film may be used. Measurement can be carried out using, for example, a vibrating sample magnetometer (VSM).

[0091] Hereinabove, one embodiment of the present invention has been described. However, the present invention is not limited to the above embodiment. For example, while the sputtering apparatus is fixed whereas the substrate is rotated in the above manufacturing method, it may be that the sputtering apparatus is rotated and that the substrate is fixed. Also, any manufacturing methods other than the method in which either the substrate or the sputtering apparatus is rotated may be used, provided that the pseudo-multilayer of the nanogranular magnetic film can be formed.

[0092] The nanogranular magnetic film according to the present embodiment may be used for any purpose. A magnetic material including the nanogranular magnetic film is suitably included in electronic components that are particularly used at high frequencies and are required to have a high Bs and a high specific resistance. Examples of such electronic components include a capacitor, a thin film inductor, a noise filter, a separator, a magneto-optical element, a TMR head, a GMR head, a magnetic sensor, and a magnetic recording medium.

EXAMPLES

[0093] Hereinafter, the present invention is specifically described based on examples.

Experiment 1

[0094] A nanogranular magnetic film was formed on a substrate using an apparatus shown in FIGS. 2 to 4. L1=90 mm, L2=2 inches, L3=3 inches, L4=2 inches, and L5=4 inches were satisfied. As the substrate, a silicon substrate having a thermal oxide film with a thickness of 0.28 mm was used. As preprocessing of the substrate, a surface treatment using an UV/O.sub.3 method was carried out for 20 minutes. After that, reverse sputtering was further carried out under an Ar gas pressure of 1 Pa, at RF 100 W, for 5 minutes.

[0095] A sputtering target having a composition that provided the magnetic film with a composition shown in each Table and having a thickness of 2 mm was prepared.

[0096] With the apparatus shown in FIGS. 2 to 4, the nanogranular magnetic film was formed using a sputtering method. Table 1 shows whether preprocessing (UV/O.sub.3 and reverse sputtering) was carried out, the rotation speed of a rotation plate at the time of sputtering, continuous film formation time, continuously formed film thickness, whether O.sub.2 was contained in the Ar gas, and whether the sputtering target was a mixed and sintered sputtering target. As the sputtering apparatus, SPF430H manufactured by CANON ANELVA CORPORATION was used.

[0097] Through simple quantification using EDX (manufactured by JEOL Ltd.), it was confirmed that the compositions of first phases and a second phase of the nanogranular magnetic film were as shown in Table 1.

[0098] Using XRF (Primus IV manufactured by Rigaku Holdings Corporation), it was confirmed that V.sub.1/(V.sub.1+V.sub.2) of the nanogranular magnetic film was as shown in Table 1.

[0099] Using a TEM (JEM-2100F manufactured by JEOL Ltd.), it was confirmed that the nanogranular magnetic film of each sample had a structure in which the first phases (nano-domains) were dispersed in the second phase.

[0100] A method of measuring parameters using 3DAP is described below. First, a measurement range having a rectangular parallelepiped shape measuring 40 nm40 nm50 nm (per side) was determined in the nanogranular magnetic film. In this continuous measurement range, 80,000 grids each measuring 1 nm1 nm1 nm were determined. Then, the Fe content, the Co content, and the second phase compound content (SiO.sub.2 content in Experiment 1) of each grid were measured using a three-dimensional atom probe (3DAP). Each element content of the grid was calculated out of a total of 100 at % of Fe, Co, Si, and O. Then, Fe/(Fe+Co) of the grid was calculated in atomic ratio. Further, the SiO.sub.2 content of the grid was calculated. Grids having a SiO.sub.2 content not lower than an average SiO.sub.2 content were classified as MX-rich grids. Grids having a SiO.sub.2 content lower than the average were classified as MX-poor grids.

[0101] The standard deviation and the average of Fe/(Fe+Co) of the MX-rich grids were calculated. The standard deviation was divided by the average to calculate the CV of the MX-rich grids. Similarly, the standard deviation and the average of Fe/(Fe+Co) of the MX-poor grids were calculated. The standard deviation was divided by the average to calculate the CV of the MX-poor grids.

[0102] Using a VSM (TM-VSM331483-HGC) manufactured by TAMAKAWA CO., LTD., saturation flux density (Bs) was measured.

[0103] Using a resistivity meter (Loresta-EP MCP-T360 manufactured by Mitsubishi Chemical Corporation), sheet resistance was measured. From this sheet resistance, experimental specific resistance was calculated.

[0104] A method of measuring benchmark specific resistance for calculating a figure of merit is described below.

[0105] First, using a conventional sputtering method not involving rotation, nanogranular magnetic films were formed under substantially the same conditions except that the first phases had different Fe:Co ratios. That is, the nanogranular magnetic films were formed under substantially the same conditions except that the Fe:Co ratios of the first phases were about 85:15, about 70:30, about 45:55, and about 15:85 respectively in atomic ratio.

[0106] Specific manufacturing conditions were as follows. The rotation speed was 0. The continuous film formation time was 25,000 seconds. The processing gas used for sputtering was a mixed gas of an Ar gas mixed with 0.2% O.sub.2 gas. The continuously formed film thickness was within a range of (5,000200) nm. The nanogranular magnetic films having the same composition with different Fe:Co ratios of the first phases were thus formed. In Experiment 1, these nanogranular magnetic films corresponded to Comparative Examples 1 to 4.

[0107] Next, using the above methods, saturation flux density (Bs) and experimental specific resistance of the nanogranular magnetic films of Comparative Examples 1 to 4 were measured.

[0108] Next, such results of Comparative Examples 2 to 4 were plotted as points in an xy plane having an x-axis representing Bs (T) and a y-axis representing specific resistance (cm). Then, using power approximation, a formula for a performance curve was derived. This formula for the performance curve derived from Comparative Examples 2 to 4 was y=0.0044x.sup.11.25.

[0109] The Bs value of each nanogranular magnetic film was substituted into the formula for the performance curve to give specific resistance, which was used as the benchmark specific resistance. A quotient of the experimental specific resistance of the nanogranular magnetic film divided by the benchmark specific resistance of the nanogranular magnetic film was defined as its figure of merit. A figure of merit of 1.20 or more was defined as good.

[0110] Comparative Example 5 was carried out as in Example 3 except that Ar was used as the processing gas for sputtering. Comparative Example 6 was carried out with an Fe chip and a Co chip each measuring 5 mm5 mm arranged on a commercially available SiO.sub.2 sputtering target so that the composition of the first phases, the composition of the second phase, and V.sub.1/(V.sub.1+V.sub.2) of the nanogranular magnetic film eventually obtained were the same as those of Example 3.

[0111] Comparative Example 7 was carried out as in Example 3 except that the UV/O.sub.3 processing and reverse sputtering were not carried out.

TABLE-US-00001 TABLE 1 Film formation conditions Continuous Continuously Mixed film formed and Magnetic film Preprocessing Rotation formation film sintered First Second Reverse speed time thickness Ar - sputtering phases phase Sample No. UV/O.sub.3 sputtering rpm s nm 0.2% O.sub.2 target Atomic ratio Atomic ratio Comparative Example 1 Yes Yes 0 25000 4877 Yes Yes Fe.sub.85Co.sub.15 SiO.sub.2 Comparative Example 2 Yes Yes 0 25000 4967 Yes Yes Fe.sub.70Co.sub.30 SiO.sub.2 Comparative Example 3 Yes Yes 0 25000 4874 Yes Yes Fe.sub.45Co.sub.55 SiO.sub.2 Comparative Example 4 Yes Yes 0 25000 4874 Yes Yes Fe.sub.15Co.sub.85 SiO.sub.2 Example 1 Yes Yes 12 1.7 1.0 Yes Yes Fe.sub.85Co.sub.15 SiO.sub.2 Example 2 Yes Yes 12 1.7 1.0 Yes Yes Fe.sub.70Co.sub.30 SiO.sub.2 Example 3 Yes Yes 12 1.7 1.0 Yes Yes Fe.sub.45Co.sub.55 SiO.sub.2 Example 4 Yes Yes 12 1.7 1.0 Yes Yes Fe.sub.15Co.sub.85 SiO.sub.2 Comparative Example 5 Yes Yes 12 1.7 1.0 No Yes Fe.sub.45Co.sub.55 SiO.sub.2 Comparative Example 6 Yes Yes 12 1.7 1.0 Yes No Fe.sub.45Co.sub.55 SiO.sub.2 Comparative Example 7 No No 12 1.7 1.0 Yes Yes Fe.sub.45Co.sub.55 SiO.sub.2 Evaluation of figure of merit Magnetic film Experimental Benchmark V.sub.1/ Film specific specific Figure (V.sub.1 + V.sub.2) thickness CV Bs resistance resistance of OK/ Sample No. % nm MX-poor MX-rich T cm cm merit Not OK Comparative Example 1 46 4877 0.103 0.092 0.584 1.86 1.87 1.00 Not OK Comparative Example 2 46 4967 0.106 0.095 0.579 2.05 2.06 1.00 Not OK Comparative Example 3 46 4874 0.108 0.098 0.563 2.80 2.82 0.99 Not OK Comparative Example 4 46 4874 0.110 0.101 0.542 4.31 4.32 1.00 Not OK Example 1 46 5012 0.168 0.262 0.691 0.94 0.28 3.35 OK Example 2 46 5101 0.172 0.273 0.689 0.97 0.29 3.35 OK Example 3 46 4876 0.187 0.280 0.667 1.16 0.42 2.77 OK Example 4 46 5033 0.204 0.292 0.636 1.75 0.72 2.45 OK Comparative Example 5 46 4875 0.143 0.140 0.633 0.81 0.75 1.07 Not OK Comparative Example 6 46 5162 0.095 0.084 0.614 1.03 1.06 0.97 Not OK Comparative Example 7 46

[0112] According to Table 1, in Examples 1 to 4, in which the rotation plate was rotated at a rotation speed of 12 rpm, the CV of Fe/(Fe+Co) of the MX-rich grids (which may hereinafter be referred to as MX-rich CV) was larger than the CV of Fe/(Fe+Co) of the MX-poor grids (which may hereinafter be referred to as MX-poor CV), and the figure of merit was good. That is, compared to the conventional nanogranular magnetic films formed without rotations, the specific resistance with respect to Bs was higher, which was good.

[0113] In both Comparative Examples 5 and 6, in which other manufacturing conditions were changed, the MX-rich CV was smaller than the MX-poor CV, and the figure of merit was less than 1.20.

[0114] In Comparative Example 7, in which preprocessing was not carried out, the film was peeled off from the substrate; and it was not possible to conduct evaluation.

Experiment 2

[0115] Comparative Examples 8 to 10 and Examples 5 to 8 were carried out as in Example 2 except that the rotation speed was changed ranging from 1 rpm to 40 rpm. Similarly, Comparative Examples 11 to 12 and Examples 9 to 11 were carried out as in Example 3 except that the rotation speed was changed ranging from 2 rpm to 40 rpm. Comparative Examples 13 to 14 and Examples 12 to 14 were carried out as in Example 4 except that the rotation speed was changed ranging from 2 rpm to 40 rpm. Table 2 shows the results.

TABLE-US-00002 TABLE 2 Film formation conditions Contin- Contin- uous uously Magnetic film film formed First Second Rotation formation film Mixed phases phase Sample speed time thickness 0.2% and Atomic Atomic No. rpm s nm O.sub.2 sintered ratio ratio Compar- 1 20 12 Yes Yes Fe.sub.70Co.sub.30 SiO.sub.2 ative Example 8 Compar- 2 10 6 Yes Yes Fe.sub.70Co.sub.30 SiO.sub.2 ative Example 9 Example 5 4 5 3 Yes Yes Fe.sub.70Co.sub.30 SiO.sub.2 Example 6 6 3.4 2 Yes Yes Fe.sub.70Co.sub.30 SiO.sub.2 Example 2 12 1.7 1.0 Yes Yes Fe.sub.70Co.sub.30 SiO.sub.2 Example 7 20 1.0 0.6 Yes Yes Fe.sub.70Co.sub.30 SiO.sub.2 Example 8 30 0.7 0.4 Yes Yes Fe.sub.70Co.sub.30 SiO.sub.2 Compar- 40 0.5 0.3 Yes Yes Fe.sub.70Co.sub.30 SiO.sub.2 ative Example 10 Compar- 2 10 6 Yes Yes Fe.sub.45Co.sub.55 SiO.sub.2 ative Example 11 Example 9 4 5 3 Yes Yes Fe.sub.45Co.sub.55 SiO.sub.2 Example 10 6 3.4 2 Yes Yes Fe.sub.45Co.sub.55 SiO.sub.2 Example 3 12 1.7 1.0 Yes Yes Fe.sub.45Co.sub.55 SiO.sub.2 Example 11 30 1.0 0.4 Yes Yes Fe.sub.45Co.sub.55 SiO.sub.2 Compar- 40 0.5 0.3 Yes Yes Fe.sub.45Co.sub.55 SiO.sub.2 ative Example 12 Compar- 2 10 6 Yes Yes Fe.sub.15Co.sub.85 SiO.sub.2 ative Example 13 Example 12 4 5 3 Yes Yes Fe.sub.15Co.sub.85 SiO.sub.2 Example 13 6 3.4 2 Yes Yes Fe.sub.15Co.sub.85 SiO.sub.2 Example 4 12 1.7 1.0 Yes Yes Fe.sub.15Co.sub.85 SiO.sub.2 Example 14 30 1.0 0.4 Yes Yes Fe.sub.15Co.sub.85 SiO.sub.2 Compar- 40 0.5 0.3 Yes Yes Fe.sub.15Co.sub.85 SiO.sub.2 ative Example 14 Evaluation of figure of merit Magnetic film Experi- Bench- Film mental mark thick- CV specific specific Figure OK/ Sample ness MX- MX- Bs resistance resistance of Not No. nm poor rich T cm cm merit OK Compar- 5012 0.123 0.113 0.601 1.17 1.35 0.87 Not ative OK Example 8 Compar- 5002 0.135 0.129 0.619 1.12 0.97 1.15 Not ative OK Example 9 Example 5 5007 0.144 0.154 0.631 1.02 0.78 1.30 OK Example 6 5086 0.153 0.214 0.660 1.00 0.47 2.12 OK Example 2 5101 0.172 0.273 0.689 0.97 0.29 3.35 OK Example 7 4972 0.302 0.364 0.662 0.91 0.46 2.00 OK Example 8 4972 0.474 0.487 0.641 0.82 0.66 1.25 OK Compar- 4916 0.514 0.496 0.635 0.77 0.73 1.06 Not ative OK Example 10 Compar- 4973 0.137 0.132 0.592 1.71 1.60 1.07 Not ative OK Example 11 Example 9 4928 0.145 0.158 0.613 1.39 1.08 1.28 OK Example 10 4891 0.159 0.222 0.645 1.22 0.61 2.00 OK Example 3 4876 0.187 0.280 0.667 1.16 0.42 2.77 OK Example 11 4890 0.468 0.484 0.631 1.05 0.78 1.34 OK Compar- 5015 0.505 0.492 0.622 0.99 0.92 1.08 Not ative OK Example 12 Compar- 4905 0.140 0.136 0.557 3.23 3.18 1.02 Not ative OK Example 13 Example 12 5021 0.146 0.161 0.590 2.07 1.66 1.24 OK Example 13 5016 0.163 0.229 0.617 1.95 1.01 1.94 OK Example 4 5033 0.204 0.292 0.636 1.75 0.72 2.45 OK Example 14 4927 0.464 0.482 0.618 1.41 0.99 1.43 OK Compar- 4973 0.498 0.488 0.608 1.30 1.19 1.09 Not ative OK Example 14

[0116] According to Table 2, in Examples 5 to 14, in which the MX-rich CV was larger than the MX-poor CV, the figure of merit was good similarly to Examples 2 to 4. By contrast, in Comparative Examples 8 to 14, in which the MX-rich CV was not more than the MX-poor CV, the figure of merit was not good.

Experiment 3

[0117] Comparative Examples 15 to 26 and Examples 15 to 26 shown in Table 3 were carried out as in Comparative Examples 2 to 4 and Examples 2 to 4 except that an additional element chip containing an additional element was placed on the sputtering target. The individual additional element chip had a rectangular parallelepiped shape having two largest 5-mm sided square surfaces and a thickness of about 0.5 mm. The number of additional element chips was determined so that the composition of the first phases and the composition of the second phase of the nanogranular magnetic films eventually obtained were as shown in each Table and that V.sub.1/(V.sub.1+V.sub.2) was close to that of Example 1. The compositions of the respective phases of the nanogranular magnetic films shown in each Table were compositions on the premise that the additional element was contained entirely in the first phases. In Experiments 3 to 4 and 6 to 8, it was actually confirmed that the additional element was substantially entirely contained in the first phases.

[0118] First, formulae for performance curves were derived from Comparative Examples having the same amount of the same additional element added but having different Fe:Co ratios. The formula for the performance curve derived from Comparative Examples 15 to 17, in which 1 atom % Nb was added, was y=0.0033x.sup.11.11. The formula for the performance curve derived from Comparative Examples 18 to 20, in which 2 atom % Nb was added, was y=0.0020x.sup.11.18. The formula for the performance curve derived from Comparative Examples 21 to 23, in which 5 atom % Nb was added, was y=0.0008x.sup.11.16. The formula for the performance curve derived from Comparative Examples 24 to 26, in which 10 atom % Nb was added, was y=0.0004x.sup.11.3.

[0119] The formula for the performance curve derived from Comparative Examples 27 to 29, in which 2 atom % Mo was added, was y=0.0016x.sup.11.37. The formula for the performance curve derived from Comparative Examples 30 to 32, in which 2 atom % Cu was added, was y=0.0022x.sup.11.05.

[0120] The Bs value of each nanogranular magnetic film was substituted into the corresponding formula for the performance curve derived from Comparative Examples having the same amount of the same additional element added to give specific resistance, which was used as the benchmark specific resistance. A quotient of the experimental specific resistance of the nanogranular magnetic film divided by the benchmark specific resistance of the nanogranular magnetic film was defined as its figure of merit. Tables 3 and 4 show the results.

TABLE-US-00003 TABLE 3 Magnetic film Evaluation of figure of merit First Second Experimental Benchmark phases phase V.sub.1/ Film CV specific specific Figure OK/ Sample Atomic Atomic (V.sub.1 + V.sub.2) thickness MX- MX- Bs resistance resistance of Not No. Rotation ratio ratio % nm poor rich T cm cm merit OK Comparative No Fe.sub.70Co.sub.30 SiO.sub.2 46 4967 0.106 0.095 0.579 2.05 2.06 1.00 Not Example 2 OK Comparative No Fe.sub.45Co.sub.55 SiO.sub.2 46 4874 0.108 0.098 0.563 2.80 2.82 0.99 Not Example 3 OK Comparative No Fe.sub.15Co.sub.85 SiO.sub.2 46 4874 0.110 0.101 0.542 4.31 4.32 1.00 Not Example 4 OK Example 2 Yes Fe.sub.70Co.sub.30 SiO.sub.2 46 5101 0.172 0.273 0.689 0.97 0.29 3.35 OK Example 3 Yes Fe.sub.45Co.sub.55 SiO.sub.2 46 4876 0.187 0.280 0.667 1.16 0.42 2.77 OK Example 4 Yes Fe.sub.15Co.sub.85 SiO.sub.2 46 5033 0.204 0.292 0.636 1.75 0.72 2.45 OK Comparative No Fe.sub.69Co.sub.30Nb.sub.1 SiO.sub.2 47 5004 0.105 0.097 0.573 1.61 1.60 1.00 Not Example 15 OK Comparative No Fe.sub.45Co.sub.54Nb.sub.1 SiO.sub.2 47 5021 0.109 0.100 0.560 2.05 2.07 0.99 Not Example 16 OK Comparative No Fe.sub.15Co.sub.84Nb.sub.1 SiO.sub.2 47 4898 0.112 0.104 0.539 3.17 3.17 1.00 Not Example 17 OK Example 15 Yes Fe.sub.69Co.sub.30Nb.sub.1 SiO.sub.2 47 5007 0.179 0.277 0.676 0.73 0.26 2.85 OK Example 16 Yes Fe.sub.45Co.sub.54Nb.sub.1 SiO.sub.2 47 5023 0.197 0.284 0.648 1.02 0.41 2.49 OK Example 17 Yes Fe.sub.15Co.sub.84Nb.sub.1 SiO.sub.2 47 4991 0.215 0.298 0.625 1.47 0.61 2.40 OK Comparative No Fe.sub.69Co.sub.29Nb.sub.2 SiO.sub.2 47 4974 0.109 0.100 0.561 1.26 1.28 0.98 Not Example 18 OK Comparative No Fe.sub.44Co.sub.54Nb.sub.2 SiO.sub.2 47 4899 0.110 0.103 0.553 1.46 1.50 0.97 Not Example 19 OK Comparative No Fe.sub.15Co.sub.83Nb.sub.2 SiO.sub.2 47 5043 0.113 0.105 0.530 2.37 2.42 0.98 Not Example 20 OK Example 18 Yes Fe.sub.69Co.sub.29Nb.sub.2 SiO.sub.2 47 5011 0.188 0.278 0.664 0.62 0.19 3.19 OK Example 19 Yes Fe.sub.44Co.sub.54Nb.sub.2 SiO.sub.2 47 4987 0.205 0.290 0.633 0.92 0.33 2.77 OK Example 20 Yes Fe.sub.15Co.sub.83Nb.sub.2 SiO.sub.2 47 4865 0.220 0.303 0.613 1.26 0.48 2.65 OK Comparative No Fe.sub.67Co.sub.28Nb.sub.5 SiO.sub.2 49 4896 0.110 0.101 0.531 0.97 0.94 1.04 Not Example 21 OK Comparative No Fe.sub.43Co.sub.52Nb.sub.5 SiO.sub.2 49 4911 0.112 0.104 0.520 1.20 1.18 1.02 Not Example 22 OK Comparative No Fe.sub.14Co.sub.81Nb.sub.5 SiO.sub.2 49 4791 0.115 0.106 0.512 1.46 1.40 1.04 Not Example 23 OK Example 21 Yes Fe.sub.67Co.sub.28Nb.sub.5 SiO.sub.2 49 5004 0.191 0.275 0.631 0.45 0.14 3.30 OK Example 22 Yes Fe.sub.43Co.sub.52Nb.sub.5 SiO.sub.2 49 4991 0.207 0.284 0.611 0.57 0.20 2.92 OK Example 23 Yes Fe.sub.14Co.sub.81Nb.sub.5 SiO.sub.2 49 4883 0.225 0.296 0.596 0.71 0.26 2.75 OK Comparative No Fe.sub.63Co.sub.27Nb.sub.10 SiO.sub.2 50 4896 0.114 0.103 0.515 0.73 0.72 1.01 Not Example 24 OK Comparative No Fe.sub.40Co.sub.50Nb.sub.10 SiO.sub.2 50 4911 0.116 0.106 0.503 0.94 0.94 1.00 Not Example 25 OK Comparative No Fe.sub.14Co.sub.76Nb.sub.10 SiO.sub.2 50 4791 0.119 0.109 0.494 1.17 1.16 1.01 Not Example 26 OK Example 24 Yes Fe.sub.63Co.sub.27Nb.sub.10 SiO.sub.2 50 5004 0.195 0.273 0.610 0.37 0.11 3.47 OK Example 25 Yes Fe.sub.40Co.sub.50Nb.sub.10 SiO.sub.2 50 4991 0.212 0.285 0.584 0.50 0.17 2.87 OK Example 26 Yes Fe.sub.14Co.sub.76Nb.sub.10 SiO.sub.2 50 4883 0.230 0.299 0.572 0.59 0.22 2.68 OK

TABLE-US-00004 TABLE 4 Magnetic film Evaluation of figure of merit First Second Experimental Benchmark phases phase V.sub.1/ Film CV specific specific Figure OK/ Sample Atomic Atomic (V.sub.1 + V.sub.2) thickness MX- MX- Bs resistance resistance of Not No. Rotation ratio ratio % nm poor rich T cm cm merit OK Comparative No Fe.sub.70Co.sub.30 SiO.sub.2 46 4967 0.106 0.095 0.579 2.05 2.06 1.00 Not Example 2 OK Comparative No Fe.sub.45Co.sub.55 SiO.sub.2 46 4874 0.108 0.098 0.563 2.80 2.82 0.99 Not Example 3 OK Comparative No Fe.sub.15Co.sub.85 SiO.sub.2 46 4874 0.110 0.101 0.542 4.31 4.32 1.00 Not Example 4 OK Example 2 Yes Fe.sub.70Co.sub.30 SiO.sub.2 46 5101 0.172 0.273 0.689 0.97 0.29 3.35 OK Example 3 Yes Fe.sub.45Co.sub.55 SiO.sub.2 46 4876 0.187 0.280 0.667 1.16 0.42 2.77 OK Example 4 Yes Fe.sub.15Co.sub.85 SiO.sub.2 46 5033 0.204 0.292 0.636 1.75 0.72 2.45 OK Comparative No Fe.sub.69Co.sub.29Nb.sub.2 SiO.sub.2 47 4974 0.109 0.100 0.561 1.26 1.28 0.98 Not Example 18 OK Comparative No Fe.sub.44Co.sub.54Nb.sub.2 SiO.sub.2 47 4899 0.110 0.103 0.553 1.46 1.50 0.97 Not Example 19 OK Comparative No Fe.sub.15Co.sub.83Nb.sub.2 SiO.sub.2 47 5043 0.113 0.105 0.530 2.37 2.42 0.98 Not Example 20 OK Example 18 Yes Fe.sub.69Co.sub.29Nb.sub.2 SiO.sub.2 47 5011 0.188 0.278 0.664 0.60 0.19 3.08 OK Example 19 Yes Fe.sub.44Co.sub.54Nb.sub.2 SiO.sub.2 47 4987 0.205 0.290 0.633 0.89 0.33 2.68 OK Example 20 Yes Fe.sub.15Co.sub.83Nb.sub.2 SiO.sub.2 47 4865 0.220 0.303 0.613 1.21 0.48 2.54 OK Comparative No Fe.sub.69Co.sub.29Mo.sub.2 SiO.sub.2 47 4965 0.107 0.099 0.558 1.23 1.22 1.01 Not Example 27 OK Comparative No Fe.sub.44Co.sub.54Mo.sub.2 SiO.sub.2 47 4889 0.109 0.101 0.552 1.37 1.37 1.00 Not Example 28 OK Comparative No Fe.sub.15Co.sub.83Mo.sub.2 SiO.sub.2 47 4932 0.111 0.104 0.524 2.50 2.48 1.01 Not Example 29 OK Example 27 Yes Fe.sub.69Co.sub.29Mo.sub.2 SiO.sub.2 47 4956 0.187 0.276 0.651 0.63 0.21 2.99 OK Example 28 Yes Fe.sub.44Co.sub.54Mo.sub.2 SiO.sub.2 47 4971 0.205 0.291 0.627 0.89 0.32 2.76 OK Example 29 Yes Fe.sub.15Co.sub.83Mo.sub.2 SiO.sub.2 47 4968 0.219 0.303 0.609 1.21 0.45 2.69 OK Comparative No Fe.sub.69Co.sub.29Cu.sub.2 SiO.sub.2 47 4881 0.108 0.100 0.565 1.22 1.21 1.01 Not Example 30 OK Comparative No Fe.sub.44Co.sub.54Cu.sub.2 SiO.sub.2 47 5004 0.110 0.102 0.555 1.41 1.47 0.96 Not Example 31 OK Comparative No Fe.sub.15Co.sub.83Cu.sub.2 SiO.sub.2 47 5012 0.112 0.104 0.534 2.25 2.25 1.00 Not Example 32 OK Example 30 Yes Fe.sub.69Co.sub.29Cu.sub.2 SiO.sub.2 47 4992 0.187 0.277 0.659 0.62 0.22 2.81 OK Example 31 Yes Fe.sub.44Co.sub.54Cu.sub.2 SiO.sub.2 47 4895 0.202 0.288 0.638 0.88 0.32 2.79 OK Example 32 Yes Fe.sub.15Co.sub.83Cu.sub.2 SiO.sub.2 47 4903 0.216 0.301 0.620 1.15 0.43 2.66 OK

[0121] According to Tables 3 and 4, in all Examples shown in Tables 3 and 4, in which the rotation plate was rotated at a rotation speed of 12 rpm, the MX-rich CV was larger than the MX-poor CV, and the figure of merit was good.

Experiment 4

[0122] In Experiments 1 to 3, three Comparative Examples corresponding to each additional element and its amount added were prepared to derive the formulae for the performance curves. In Experiment 4, a way of temporarily checking properties of nanogranular magnetic films using a simple method was explored.

[0123] A formula for a performance curve was derived using power approximation. Thus, the formula was represented by a general formula y=Ax.sup.B.

[0124] In comparison between the performance curves derived in Experiments 1 to 3, a difference in A resulting from a change of the amount of the additional element added was large, whereas a difference in B resulting from such a change was small. By contrast, provided that the amount of the additional element added stayed the same, there were small differences in A and B despite a change of the additional element.

[0125] Thus, it was assumed that it was possible to conduct sufficiently accurate evaluation by calculating the figure of merit on the supposition that the additional element was Nb even if the additional element was different from Nb.

[0126] A and B of the performance curves derived from Comparative Examples 2 to 4 and 15 to 26 were as follows: A=0.0044 and B=11.25 when there was no additional element (additional element 0%); A=0.0033 and B=11.11 at an additional element of 1%; A=0.0020 and B=11.18 at an additional element of 2%; A=0.0008 and B=11.16 at an additional element of 5%; and A=0.0004 and B=11.30 at an additional element of 10%. Thus, the value of A was required to be selected according to the concentration of the additional element, and the value of B was able to stay fixed regardless of the concentration of the additional element.

[0127] Details of how to select the values of A and B in the way of temporarily checking properties of the nanogranular magnetic films using the simple method are provided below.

(How to select value of A)

[0128] A graph having a horizontal axis representing the amount of the additional element added (%) and a vertical axis representing the value of A was created. Then, point a (0, 0.0044), point b (1, 0.0033), point c (2, 0.0020), point d (5, 0.0008), and point e (10, 0.0004) were plotted in the graph. Points a and b were connected with a straight line. Points b and c were connected with a straight line. Points c and d were connected with a straight line. Points d and e were connected with a straight line. Using the resulting line graph, the value of A was selected according to the amount of the additional element added.

[0129] For example, if the additional element added was 0.6%, the value of A selected would be 0.00440.4+0.00330.6=0.00374.

(How to select value of B)

[0130] Regardless of the concentration of the additional element, 11.20 was selected as the value of B. This value of B was an arithmetic mean (average) of 11.25, 11.11, 11.18, 11.16, and 11.30, which were the values of B at the above-mentioned amounts added.

(Definition of Simple Figure of Merit)

[0131] A simple figure of merit was defined as follows. Values of A and B selected using the above methods according to the amount added were substituted into the general formula y=Ax.sup.B. This formula with the substituted values was defined as a formula for a simple performance curve. Benchmark specific resistance found from this formula was defined as simple benchmark specific resistance. A figure of merit found from the simple benchmark specific resistance and the experimental specific resistance was defined as the simple figure of merit. The formula for the simple performance curve allowed the simple figure of merit to be calculated for evaluation of properties without manufacture of samples at a rotation speed of 0 rpm.

[0132] The figure of merit and the simple figure of merit of Comparative Examples 11 to 12 and Examples 3 and 9 to 11, which were under substantially the same conditions except for the rotation speed, were compared. Because the additional element of these samples was 0%, the parameters of the formula for the simple performance curve were A=0.0044 and B=11.20. Table 5 shows the results of calculation of the simple figure of merit as well as the figure of merit.

[0133] The figure of merit and the simple figure of merit of Examples 18 to 20, 27 to 29, and 30 to 32, which had 2% additional element added and had the additional element varying, were compared. Because the amount of the additional element was 2%, the parameters of the formula for the simple performance curve were A=0.0020 and B=11.20. Table 6 shows the results of calculation of the simple figure of merit as well as the figure of merit.

TABLE-US-00005 TABLE 5 Film formation conditions Contin- Contin- uous uously Magnetic film film formed First Second Film Rotation formation film Mixed phases phase thick- CV Sample speed time thick- 0.2% and Atomic Atomic ness MX- No. rpm s ness O.sub.2 sintered ratio ratio nm poor Compar- 2 10 6 Yes Yes Fe.sub.45Co.sub.55 SiO.sub.2 4973 0.137 ative Example 11 Example 9 4 5 3 Yes Yes Fe.sub.45Co.sub.55 SiO.sub.2 4928 0.145 Example 10 6 3.4 2 Yes Yes Fe.sub.45Co.sub.55 SiO.sub.2 4891 0.159 Example 3 12 1.7 1.0 Yes Yes Fe.sub.45Co.sub.55 SiO.sub.2 4876 0.187 Example 11 30 1.0 0.4 Yes Yes Fe.sub.45Co.sub.55 SiO.sub.2 4890 0.468 Compar- 40 0.5 0.3 Yes Yes Fe.sub.45Co.sub.55 SiO.sub.2 5015 0.505 ative Example 12 Evaluation of figure of merit Simple Experi- bench- Bench- Magnetic film mental mark Simple mark CV specific specific figure specific Figure OK/ Sample MX- Bs resistance resistance of resistance of Not No. rich T cm cm merit cm merit OK Compar- 0.132 0.592 1.71 1.56 1.10 1.60 1.07 Not ative OK Example 11 Example 9 0.158 0.613 1.39 1.06 1.32 1.08 1.28 OK Example 10 0.222 0.645 1.22 0.60 2.04 0.61 2.00 OK Example 3 0.280 0.667 1.16 0.41 2.83 0.42 2.77 OK Example 11 0.484 0.631 1.05 0.76 1.37 0.78 1.34 OK Compar- 0.492 0.622 0.99 0.90 1.10 0.92 1.08 Not ative OK Example 12

TABLE-US-00006 TABLE 6 Evaluation of figure of merit Simple Magnetic film Experi- bench- Bench- First Second Film mental mark Simple mark phases phase V.sub.1/ thick- CV specific specific figure specific Figure OK/ Sample Atomic Atomic (V.sub.1 + V.sub.2) ness MX- MX- Bs resistance resistance of resistance of Not No. ratio ratio % nm poor rich T cm cm merit cm merit OK Example 18 Fe.sub.69Co.sub.29Nb.sub.2 SiO.sub.2 47 5011 0.188 0.278 0.664 0.60 0.20 3.06 0.19 3.08 OK Example 19 Fe.sub.44Co.sub.54Nb.sub.2 SiO.sub.2 47 4987 0.205 0.290 0.633 0.89 0.34 2.66 0.33 2.68 OK Example 20 Fe.sub.15Co.sub.83Nb.sub.2 SiO.sub.2 47 4865 0.220 0.303 0.613 1.21 0.48 2.52 0.48 2.54 OK Example 27 Fe.sub.69Co.sub.29Mo.sub.2 SiO.sub.2 47 4956 0.187 0.276 0.651 0.63 0.24 2.57 0.21 2.99 OK Example 28 Fe.sub.44Co.sub.54Mo.sub.2 SiO.sub.2 47 4971 0.205 0.291 0.627 0.89 0.37 2.39 0.32 2.76 OK Example 29 Fe.sub.15Co.sub.83Mo.sub.2 SiO.sub.2 47 4968 0.219 0.303 0.609 1.21 0.52 2.34 0.45 2.69 OK Example 30 Fe.sub.69Co.sub.29Cu.sub.2 SiO.sub.2 47 4992 0.187 0.277 0.659 0.62 0.21 2.90 0.22 2.81 OK Example 31 Fe.sub.44Co.sub.54Cu.sub.2 SiO.sub.2 47 4895 0.202 0.288 0.638 0.88 0.31 2.87 0.32 2.79 OK Example 32 Fe.sub.15Co.sub.83Cu.sub.2 SiO.sub.2 47 4903 0.216 0.301 0.620 1.15 0.42 2.72 0.43 2.66 OK

[0134] In all Comparative Examples and Examples shown in Tables 5 and 6, the figure of merit and the simple figure of merit were not the same but were relatively close. Thus, it was possible to conduct sufficiently accurate evaluation using the simple figure of merit.

Experiment 5

[0135] Examples 33 to 44 were carried out as in Examples 19, 28, and 31 except that the additional element was changed from those of Examples 19, 28, and 31 to find the MX-rich CV, the MX-poor CV, and the simple figure of merit. Examples 45 to 46 were carried out as in Example 22 except that the additional element was changed from that of Example 22 to find the MX-rich CV, the MX-poor CV, and the simple figure of merit. Examples 47 to 48 were carried out as in Example 25 except that the additional element was changed from that of Example 25 to find the MX-rich CV, the MX-poor CV, and the simple figure of merit. Table 7 shows the results.

TABLE-US-00007 TABLE 7 Evaluation of figure of merit Simple Magnetic film Experimental benchmark Simple First Second V.sub.1/ Film specific specific figure phases phase (V.sub.1 + V.sub.2) thickness CV Bs resistance resistance of OK / Sample No. Atomic ratio Atomic ratio % nm MX-poor MX-rich T cm cm merit Not OK Example 19 Fe.sub.44Co.sub.54Nb.sub.2 SiO.sub.2 47 4987 0.205 0.290 0.633 0.89 0.34 2.66 OK Example 28 Fe.sub.44Co.sub.54Mo.sub.2 SiO.sub.2 47 4971 0.205 0.291 0.627 0.89 0.37 2.39 OK Example 31 Fe.sub.44Co.sub.54Cu.sub.2 SiO.sub.2 47 4895 0.202 0.288 0.638 0.88 0.31 2.87 OK Example 33 Fe.sub.44Co.sub.54Ti.sub.2 SiO.sub.2 47 5031 0.203 0.289 0.645 0.82 0.27 3.02 OK Example 34 Fe.sub.44Co.sub.54Zr.sub.2 SiO.sub.2 47 5012 0.204 0.289 0.640 0.86 0.30 2.90 OK Example 35 Fe.sub.44Co.sub.54Cr.sub.2 SiO.sub.2 47 5026 0.206 0.290 0.634 0.95 0.33 2.88 OK Example 36 Fe.sub.44Co.sub.54Mn.sub.2 SiO.sub.2 47 5079 0.202 0.284 0.639 0.87 0.30 2.88 OK Example 37 Fe.sub.45Co.sub.53B.sub.2 SiO.sub.2 47 5063 0.189 0.281 0.635 1.02 0.32 3.15 OK Example 38 Fe.sub.44Co.sub.54C.sub.2 SiO.sub.2 47 5045 0.194 0.282 0.629 1.01 0.36 2.81 OK Example 39 Fe.sub.45Co.sub.53P.sub.2 SiO.sub.2 47 5038 0.181 0.276 0.633 1.04 0.34 3.10 OK Example 40 Fe.sub.44Co.sub.54Ge.sub.2 SiO.sub.2 47 5019 0.196 0.283 0.630 0.97 0.35 2.74 OK Example 41 Fe.sub.44Co.sub.54V.sub.2 SiO.sub.2 47 5007 0.206 0.290 0.635 0.93 0.32 2.87 OK Example 42 Fe.sub.45Co.sub.53W.sub.2 SiO.sub.2 47 4913 0.207 0.292 0.632 0.90 0.34 2.64 OK Example 43 Fe.sub.44Co.sub.54Al.sub.2 SiO.sub.2 47 4934 0.201 0.283 0.634 0.95 0.33 2.88 OK Example 44 Fe.sub.44Co.sub.54Ni.sub.2 SiO.sub.2 47 4944 0.184 0.283 0.651 0.82 0.24 3.35 OK Example 22 Fe.sub.43Co.sub.52Nb.sub.5 SiO.sub.2 49 4991 0.207 0.284 0.611 0.57 0.20 2.86 OK Example 45 Fe.sub.43Co.sub.52P.sub.5 SiO.sub.2 49 5011 0.191 0.273 0.605 0.70 0.22 3.15 OK Example 46 Fe.sub.43Co.sub.52Ni.sub.5 SiO.sub.2 49 5003 0.197 0.278 0.628 0.52 0.15 3.55 OK Example 25 Fe.sub.40Co.sub.50Nb.sub.10 SiO.sub.2 50 4991 0.212 0.285 0.584 0.50 0.17 3.03 OK Example 47 Fe.sub.40Co.sub.50P.sub.10 SiO.sub.2 50 5028 0.204 0.274 0.577 0.55 0.19 2.91 OK Example 48 Fe.sub.40Co.sub.50Ni.sub.10 SiO.sub.2 50 5008 0.221 0.292 0.606 0.43 0.11 3.94 OK

[0136] According to Table 7, even with the varied additional element, the MX-rich CV of the nanogranular magnetic films was larger than the MX-poor CV thereof, and the simple figure of merit was good. If three Comparative Examples corresponding to the composition of each Example were prepared to calculate the figure of merit, it would be highly probable that the calculated figure of merit would be 1.20 or more.

Experiment 6

[0137] Changes in the MX-rich CV, the MX-poor CV, and the simple figure of merit when the rotation speed was changed in manufacture of nanogranular magnetic films having an additional element added were confirmed. Comparative Examples 33 to 34 and Examples 49 to 50 were carried out as in Example 31 except that the rotation speed was changed. Comparative Examples 35 to 36 and Examples 51 to 52 were carried out as in Example 39 except that the rotation speed was changed. Comparative Examples 37 to 38 and Examples 53 to 54 were carried out as in Example 44 except that the rotation speed was changed. Table 8 shows the results.

TABLE-US-00008 TABLE 8 Film formation conditions Continuously Continuous formed Magnetic film film film First Second Rotation formation thick- Mixed phases phase Sample speed time ness 0.2% and Atomic Atomic No. rpm s nm O.sub.2 sintered ratio ratio Compar- 2 10 6.0 Yes Yes Fe.sub.44Co.sub.54Cu.sub.2 SiO.sub.2 ative Example 33 Example 49 4 5 3.0 Yes Yes Fe.sub.44Co.sub.54Cu.sub.2 SiO.sub.2 Example 31 12 1.7 1.0 Yes Yes Fe.sub.44Co.sub.54Cu.sub.2 SiO.sub.2 Example 50 30 1.0 0.4 Yes Yes Fe.sub.44Co.sub.54Cu.sub.2 SiO.sub.2 Compar- 40 0.5 0.3 Yes Yes Fe.sub.44Co.sub.54Cu.sub.2 SiO.sub.2 ative Example 34 Compar- 2 10 6.0 Yes Yes Fe.sub.44Co.sub.54P.sub.2 SiO.sub.2 ative Example 35 Example 51 4 5 3.0 Yes Yes Fe.sub.44Co.sub.54P.sub.2 SiO.sub.2 Example 39 12 1.7 1.0 Yes Yes Fe.sub.44Co.sub.54P.sub.2 SiO.sub.2 Example 52 30 1.0 0.4 Yes Yes Fe.sub.44Co.sub.54P.sub.2 SiO.sub.2 Compar- 40 0.5 0.3 Yes Yes Fe.sub.44Co.sub.54P.sub.2 SiO.sub.2 ative Example 36 Compar- 2 10 6.0 Yes Yes Fe.sub.44Co.sub.54Ni.sub.2 SiO.sub.2 ative Example 37 Example 53 4 5 3.0 Yes Yes Fe.sub.44Co.sub.54Ni.sub.2 SiO.sub.2 Example 44 12 1.7 1.0 Yes Yes Fe.sub.44Co.sub.54Ni.sub.2 SiO.sub.2 Example 54 30 1.0 0.4 Yes Yes Fe.sub.44Co.sub.54Ni.sub.2 SiO.sub.2 Compar- 40 0.5 0.3 Yes Yes Fe.sub.44Co.sub.54Ni.sub.2 SiO.sub.2 ative Example 38 Evaluation of figure of merit Simple Magnetic film Experi- bench- Film mental mark Simple thick- CV specific specific figure OK/ Sample ness MX- MX- Bs resistance resistance of Not No. nm poor rich T cm cm merit OK Compar- 4872 0.139 0.133 0.575 1.13 0.98 1.15 Not ative OK Example 33 Example 49 4905 0.148 0.162 0.598 1.02 0.63 1.61 OK Example 31 4895 0.202 0.288 0.638 0.88 0.31 2.87 OK Example 50 4913 0.470 0.491 0.619 0.70 0.43 1.63 OK Compar- 4920 0.528 0.503 0.602 0.56 0.59 0.95 Not ative OK Example 34 Compar- 5033 0.128 0.123 0.570 1.27 1.08 1.17 Not ative OK Example 35 Example 51 5072 0.134 0.156 0.592 1.15 0.71 1.62 OK Example 39 5038 0.181 0.276 0.633 1.04 0.34 3.10 OK Example 52 5014 0.450 0.477 0.614 0.81 0.47 1.72 OK Compar- 4996 0.507 0.490 0.598 0.70 0.63 1.10 Not ative OK Example 36 Compar- 4884 0.130 0.125 0.582 0.98 0.86 1.14 Not ative OK Example 37 Example 53 4913 0.141 0.158 0.611 0.91 0.50 1.83 OK Example 44 4944 0.184 0.279 0.655 0.82 0.23 3.59 OK Example 54 4967 0.466 0.481 0.623 0.73 0.40 1.82 OK Compar- 4934 0.513 0.495 0.606 0.61 0.55 1.12 Not ative OK Example 38

[0138] According to Table 8, in Examples 31, 39, 44, and 49 to 54, the MX-rich CV was larger than the MX-poor CV, and the simple figure of merit was good. That is, no difference depending on the additional element was confirmed.

Experiment 7

[0139] Experiment 7 was conducted as in Example 3 except that the second phase compound was changed from SiO.sub.2. Examples 62 to 64 had different ratios of SiO.sub.2 to Al.sub.2O.sub.3 in the second phase. In Experiment 7, the simple figure of merit was calculated on the supposition that, even if the compound contained in the second phase was different from SiO.sub.2, the compound was equivalent to SiO.sub.2. Table 9 shows the results.

TABLE-US-00009 TABLE 9 Evaluation of figure of merit Simple Magnetic film Experi- bench- First Second Film mental mark Simple phases phase V.sub.1/ thick- CV specific specific figure OK/ Sample Atomic Atomic (V.sub.1 + V.sub.2) ness MX- MX- Bs resistance resistance of Not No. ratio ratio % nm poor rich T cm cm merit OK Example 3 Fe.sub.45Co.sub.55 SiO.sub.2 46 4876 0.187 0.280 0.667 1.16 0.41 2.83 OK Example 55 Fe.sub.45Co.sub.55 Al.sub.2O.sub.3 46 4922 0.196 0.285 0.662 1.04 0.45 2.33 OK Example 56 Fe.sub.45Co.sub.55 AlN 46 4887 0.214 0.299 0.657 0.97 0.49 2.00 OK Example 57 Fe.sub.45Co.sub.55 Si.sub.3N.sub.4 46 4929 0.221 0.298 0.648 1.09 0.57 1.92 OK Example 58 Fe.sub.45Co.sub.55 MgF.sub.2 46 4887 0.233 0.307 0.646 1.08 0.59 1.84 OK Example 59 Fe.sub.45Co.sub.55 BN 46 4930 0.249 0.320 0.648 1.01 0.57 1.78 OK Example 60 Fe.sub.45Co.sub.55 MgO 46 4953 0.254 0.325 0.648 1.00 0.57 1.76 OK Example 61 Fe.sub.45Co.sub.55 GaO.sub.2 46 5027 0.310 0.366 0.647 0.92 0.58 1.59 OK Example 62 Fe.sub.45Co.sub.55 SiO.sub.2 + Al.sub.2O.sub.3 (1:1 vol %) 46 4954 0.192 0.283 0.660 1.10 0.46 2.38 OK Example 63 Fe.sub.45Co.sub.55 SiO.sub.2 + Al.sub.2O.sub.3 (4:1 vol %) 46 5025 0.190 0.282 0.662 1.13 0.45 2.53 OK Example 64 Fe.sub.45Co.sub.55 SiO.sub.2 + Al.sub.2O.sub.3 (1:4 vol %) 46 4916 0.201 0.285 0.658 1.06 0.48 2.22 OK

[0140] According to Table 9, even with the varied second phase compound, the MX-rich CV of the nanogranular magnetic films was larger than the MX-poor CV thereof, and the simple figure of merit was good. If three Comparative Examples corresponding to the composition of each Example were prepared to calculate the figure of merit, it would be highly probable that the calculated figure of merit would be 1.20 or more.

Experiment 8-1

[0141] Experiment 8-1 was conducted as in Example 3 except that V.sub.1/(V.sub.1+V.sub.2) was greatly changed. In Experiment 8-1, the simple figure of merit was calculated on the supposition that, even if V.sub.1/(V.sub.1+V.sub.2) was greatly different from 46%, V.sub.1/(V.sub.1+V.sub.2) was about 46%. Table 10-1 shows the results.

TABLE-US-00010 TABLE 10-1 Evaluation of figure of merit Simple Magnetic film Experimental benchmark Simple First Second V.sub.1/ Film specific specific figure phases phase (V.sub.1 + V.sub.2) thickness CV Bs resistance resistance of OK/ Sample No. Atomic ratio Atomic ratio % nm MX-poor MX-rich T cm cm merit Not OK Example 101a Fe.sub.45Co.sub.55 SiO.sub.2 35 4736 0.161 0.168 0.405 138.0 109.6 1.26 OK Example 65 Fe.sub.45Co.sub.55 SiO.sub.2 40 4965 0.172 0.263 0.521 16.5 6.5 2.53 OK Example 3 Fe.sub.45Co.sub.55 SiO.sub.2 46 4876 0.187 0.280 0.667 1.16 0.41 2.83 OK Example 101 Fe.sub.45Co.sub.55 SiO.sub.2 50 4771 0.199 0.289 0.704 0.49 0.22 2.19 OK Example 102 Fe.sub.45Co.sub.55 SiO.sub.2 52 4826 0.204 0.299 0.821 0.103 0.040 2.57 OK Example 103 Fe.sub.45Co.sub.55 SiO.sub.2 54 4739 0.217 0.304 0.848 0.067 0.028 2.40 OK Example 66 Fe.sub.45Co.sub.55 SiO.sub.2 56 4898 0.234 0.310 0.899 0.030 0.014 2.07 OK Example 104 Fe.sub.45Co.sub.55 SiO.sub.2 58 4911 0.242 0.317 0.931 0.022 0.0098 2.24 OK Example 67 Fe.sub.45Co.sub.55 SiO.sub.2 60 4906 0.250 0.324 0.951 0.016 0.0077 2.07 OK Example 68 Fe.sub.45Co.sub.55 SiO.sub.2 65 4934 0.274 0.338 1.050 0.0052 0.0025 2.04 OK Example 104a Fe.sub.45Co.sub.55 SiO.sub.2 70 5078 0.331 0.342 1.148 0.0012 0.0009 1.28 OK

[0142] According to Table 10-1, even with greatly varied V.sub.1/(V.sub.1+V.sub.2), the MX-rich CV of the nanogranular magnetic films was larger than the MX-poor CV thereof, and the simple figure of merit was good. If three Comparative Examples corresponding to each Example were prepared to calculate the figure of merit, it would be highly probable that the calculated figure of merit would be 1.20 or more.

Experiment 8-2

[0143] Experiment 8-2 was conducted as in Examples 66, 67, 102, and 103 except that the ratio of Fe to Co in the first phases was changed. Table 10-2 shows the results.

[0144] Further, this experiment was conducted as in Examples 103 and 108 to 110 except that the compound contained in the second phase was changed. Table 10-2 shows the results.

TABLE-US-00011 TABLE 10-2 Evaluation of figure of merit Simple Magnetic film Experimental benchmark Simple First Second V.sub.1/ Film specific specific figure phases phase (V.sub.1 + V.sub.2) thickness CV Bs resistance resistance of OK/ Sample No. Atomic ratio Atomic ratio % nm MX-poor MX-rich T cm cm merit Not OK Example 105a Fe.sub.5Co.sub.95 SiO.sub.2 52 4860 0.235 0.262 0.773 0.148 0.079 1.88 OK Example 105 Fe.sub.15Co.sub.85 SiO.sub.2 52 4834 0.212 0.306 0.801 0.134 0.053 2.54 OK Example 102 Fe.sub.45Co.sub.55 SiO.sub.2 52 4826 0.204 0.299 0.821 0.104 0.040 2.60 OK Example 106 Fe.sub.60Co.sub.40 SiO.sub.2 52 4799 0.202 0.289 0.872 0.059 0.020 2.89 OK Example 107 Fe.sub.85Co.sub.15 SiO.sub.2 52 4720 0.195 0.281 0.888 0.044 0.017 2.64 OK Example 107a Fe.sub.90Co.sub.10 SiO.sub.2 52 4703 0.191 0.274 0.874 0.038 0.020 1.91 OK Example 108 Fe.sub.15Co.sub.85 SiO.sub.2 54 4865 0.221 0.309 0.821 0.090 0.040 2.25 OK Example 103 Fe.sub.45Co.sub.55 SiO.sub.2 54 4739 0.217 0.304 0.848 0.067 0.028 2.40 OK Example 109 Fe.sub.60Co.sub.40 SiO.sub.2 54 4697 0.210 0.298 0.895 0.041 0.015 2.69 OK Example 110 Fe.sub.85Co.sub.15 SiO.sub.2 54 4722 0.200 0.287 0.907 0.032 0.013 2.44 OK Example 111 Fe.sub.15Co.sub.85 SiO.sub.2 56 4872 0.244 0.315 0.866 0.044 0.022 2.00 OK Example 66 Fe.sub.45Co.sub.55 SiO.sub.2 56 4898 0.234 0.310 0.899 0.030 0.014 2.07 OK Example 112 Fe.sub.60Co.sub.40 SiO.sub.2 56 4901 0.217 0.302 0.932 0.022 0.010 2.27 OK Example 113 Fe.sub.85Co.sub.15 SiO.sub.2 56 4945 0.205 0.290 0.945 0.018 0.008 2.17 OK Example 114 Fe.sub.15Co.sub.85 SiO.sub.2 60 4935 0.256 0.333 0.922 0.022 0.011 2.01 OK Example 67 Fe.sub.45Co.sub.55 SiO.sub.2 60 4906 0.250 0.324 0.951 0.016 0.008 2.07 OK Example 115 Fe.sub.60Co.sub.40 SiO.sub.2 60 4910 0.239 0.310 0.982 0.012 0.005 2.23 OK Example 116 Fe.sub.85Co.sub.15 SiO.sub.2 60 4874 0.221 0.299 0.996 0.010 0.005 2.13 OK Example 117 Fe.sub.15Co.sub.85 Al.sub.2O.sub.3 54 4845 0.223 0.311 0.818 0.085 0.042 2.04 OK Example 118 Fe.sub.45Co.sub.55 Al.sub.2O.sub.3 54 4865 0.212 0.300 0.847 0.064 0.028 2.26 OK Example 119 Fe.sub.60Co.sub.40 Al.sub.2O.sub.3 54 4898 0.206 0.294 0.891 0.039 0.016 2.43 OK Example 120 Fe.sub.85Co.sub.15 Al.sub.2O.sub.3 54 4907 0.198 0.284 0.905 0.031 0.013 2.30 OK

[0145] According to Table 10-2, even with the varied composition of the first phases and/or the varied compound contained in the second phase, the MX-rich CV of the nanogranular magnetic films was larger than the MX-poor CV thereof, and the simple figure of merit was good. If three Comparative Examples corresponding to V.sub.1/(V.sub.1+V.sub.2) of each Example were prepared to calculate the figure of merit, it would be highly probable that the calculated figure of merit would be 1.20 or more.

Experiment 8-3

[0146] Experiment 8-3 was conducted as in Examples 67, 102, 103, 108 to 110, and 117 to 120 except that nitrogen was introduced into the second phase. To introduce nitrogen into the second phase, nitrogen with 0.2% oxygen was introduced into the processing gas used for sputtering. By changing the nitrogen concentration of the processing gas, the ratio of the nitrogen content to the total content of oxygen and nitrogen in the second phase (N/(N+O)) was changed. Table 10-3 shows the results.

[0147] In Examples 121 to 124, an Ar gas into which 1% nitrogen was introduced was used as the processing gas. In Examples 125 to 128, an Ar gas into which 2% nitrogen was introduced was used as the processing gas. In Examples 129 to 132 and 139 to 142, an Ar gas into which 4% nitrogen was introduced was used as the processing gas. In Examples 133 to 138, an Ar gas into which 6% nitrogen was introduced was used as the processing gas. In all Examples, the gas flow rate of the processing gas was 20 sccm (total of Ar and nitrogen).

[0148] A method of measuring N/(N+O) was as follows. At the time of sputtering of each nanogranular magnetic film, Ni foil measuring 20 mm20 mm50 m was prepared together with the silicon substrate having the thermal oxide film. 50 m was the length in the thickness direction. Then, an impulse heat melting extraction method using TC600 manufactured by LECO JAPAN CORPORATION was employed to measure N/(N+O) of the nanogranular magnetic film formed on the Ni foil.

TABLE-US-00012 TABLE 10-3 Evaluation of figure of merit Magnetic film Simple First Second Experimental benchmark Simple phases phase N/ V.sub.1/ Film CV specific specific figure Sample Atomic Atomic (N + 0) (V.sub.1 + V.sub.2) thickness MX- MX- Bs resistance resistance of OK/ No. ratio ratio Atom % % nm poor rich T cm cm merit Not OK Example 108 Fe.sub.15Co.sub.85 SiO.sub.2 0 54 4865 0.218 0.306 0.821 0.090 0.040 2.25 OK Example 103 Fe.sub.45Co.sub.55 SiO.sub.2 0 54 4739 0.208 0.296 0.848 0.067 0.028 2.40 OK Example 109 Fe.sub.60Co.sub.40 SiO.sub.2 0 54 4697 0.202 0.289 0.895 0.041 0.015 2.69 OK Example 110 Fe.sub.85Co.sub.15 SiO.sub.2 0 54 4722 0.195 0.281 0.907 0.032 0.013 2.44 OK Example 121 Fe.sub.15Co.sub.85 SiON 15 54 5022 0.221 0.309 0.817 0.088 0.042 2.08 OK Example 122 Fe.sub.45Co.sub.55 SiON 15 54 5065 0.212 0.300 0.842 0.066 0.030 2.19 OK Example 123 Fe.sub.60Co.sub.40 SiON 15 54 5015 0.205 0.293 0.891 0.039 0.016 2.43 OK Example 124 Fe.sub.85Co.sub.15 SiON 15 54 5004 0.197 0.283 0.903 0.031 0.014 2.25 OK Example 125 Fe.sub.15Co.sub.85 SiON 24 54 5135 0.228 0.315 0.815 0.084 0.043 1.93 OK Example 126 Fe.sub.45Co.sub.55 SiON 24 54 5094 0.217 0.305 0.840 0.063 0.031 2.03 OK Example 127 Fe.sub.60Co.sub.40 SiON 24 54 5107 0.211 0.299 0.889 0.037 0.016 2.25 OK Example 128 Fe.sub.85Co.sub.15 SiON 24 54 5147 0.202 0.289 0.900 0.030 0.014 2.10 OK Example 129 Fe.sub.15Co.sub.85 SiON 35 54 5164 0.233 0.320 0.812 0.081 0.045 1.79 OK Example 130 Fe.sub.45Co.sub.55 SiON 35 54 5120 0.223 0.311 0.836 0.060 0.033 1.83 OK Example 131 Fe.sub.60Co.sub.40 SiON 35 54 5142 0.215 0.303 0.885 0.036 0.017 2.08 OK Example 132 Fe.sub.85Co.sub.15 SiON 35 54 5158 0.205 0.293 0.895 0.029 0.015 1.90 OK Example 133 Fe.sub.15Co.sub.85 SiON 46 54 5069 0.244 0.329 0.810 0.078 0.047 1.67 OK Example 134 Fe.sub.45Co.sub.55 SiON 46 54 5026 0.231 0.318 0.833 0.058 0.034 1.70 OK Example 135 Fe.sub.60Co.sub.40 SiON 46 54 5082 0.221 0.309 0.878 0.036 0.019 1.91 OK Example 136 Fe.sub.85Co.sub.15 SiON 46 54 5027 0.211 0.299 0.892 0.028 0.016 1.77 OK Example 102 Fe.sub.45Co.sub.55 SiO.sub.2 0 52 4826 0.208 0.296 0.821 0.104 0.040 2.60 OK Example 103 Fe.sub.45Co.sub.55 SiO.sub.2 0 54 4739 0.208 0.296 0.848 0.067 0.028 2.40 OK Example 67 Fe.sub.45Co.sub.55 SiO.sub.2 0 60 4906 0.250 0.324 0.951 0.016 0.0077 2.07 OK Example 137 Fe.sub.45Co.sub.55 SiON 46 52 5104 0.223 0.310 0.815 0.082 0.043 1.89 OK Example 134 Fe.sub.45Co.sub.55 SiON 46 54 5026 0.231 0.318 0.833 0.058 0.034 1.70 OK Example 138 Fe.sub.45Co.sub.55 SiON 46 60 5147 0.251 0.334 0.939 0.015 0.0089 1.68 OK Example 117 Fe.sub.15Co.sub.85 Al.sub.2O.sub.3 0 54 4845 0.223 0.311 0.818 0.085 0.042 2.04 OK Example 118 Fe.sub.45Co.sub.55 Al.sub.2O.sub.3 0 54 4865 0.212 0.300 0.847 0.064 0.028 2.26 OK Example 119 Fe.sub.60Co.sub.40 Al.sub.2O.sub.3 0 54 4898 0.206 0.294 0.891 0.039 0.016 2.43 OK Example 120 Fe.sub.85Co.sub.15 Al.sub.2O.sub.3 0 54 4907 0.198 0.284 0.905 0.031 0.013 2.30 OK Example 139 Fe.sub.15Co.sub.85 AlON 21 54 5007 0.231 0.318 0.813 0.082 0.045 1.83 OK Example 140 Fe.sub.45Co.sub.55 AlON 21 54 5074 0.219 0.307 0.838 0.061 0.032 1.92 OK Example 141 Fe.sub.60Co.sub.40 AlON 21 54 5023 0.213 0.301 0.887 0.036 0.017 2.14 OK Example 142 Fe.sub.85Co.sub.15 AlON 21 54 5008 0.205 0.293 0.898 0.029 0.015 1.98 OK

[0149] According to Table 10-3, even with the varied composition of the first phases and/or the varied compound contained in the second phase, the MX-rich CV of the nanogranular magnetic films was larger than the MX-poor CV thereof, and the simple figure of merit was good. If three Comparative Examples corresponding to each Example were prepared to calculate the figure of merit, it would be highly probable that the calculated figure of merit would be 1.20 or more.

Experiment 8-4

[0150] Examples 143 to 158 were carried out as in Examples 121 to 124 except that an additional element chip containing an additional element was placed on the sputtering target similarly to Experiment 3. Further, Examples 159 to 162 were carried out as in Examples 155 to 158 except that the nitrogen concentration of the processing gas was changed to 6%. Table 10-4 shows the results.

TABLE-US-00013 TABLE 10-4 Evaluation of figure of merit Magnetic film Simple First Second Experimental benchmark Simple phases phase N/ V.sub.1/ Film CV specific specific figure OK/ Sample Atomic Atomic (N + 0) (V.sub.1 + V.sub.2) thickness MX- MX- Bs resistance resistance of Not No. ratio ratio Atom % % nm poor rich T cm cm merit OK Example 121 Fe.sub.15Co.sub.85 SiON 15 54 5022 0.221 0.309 0.817 0.09 0.04 2.08 OK Example 122 Fe.sub.45Co.sub.55 SiON 15 54 5065 0.212 0.300 0.842 0.07 0.03 2.19 OK Example 123 Fe.sub.60Co.sub.40 SiON 15 54 5015 0.205 0.293 0.891 0.04 0.02 2.43 OK Example 124 Fe.sub.85Co.sub.15 SiON 15 54 5004 0.197 0.283 0.903 0.03 0.01 2.25 OK Example 143 Fe.sub.15Co.sub.83Nb.sub.2 SiON 15 54 4865 0.229 0.316 0.812 0.08 0.05 1.81 OK Example 144 Fe.sub.44Co.sub.54Nb.sub.2 SiON 15 54 4877 0.221 0.309 0.834 0.06 0.03 1.87 OK Example 145 Fe.sub.59Co.sub.39Nb.sub.2 SiON 15 54 4898 0.211 0.299 0.882 0.04 0.02 2.06 OK Example 146 Fe.sub.83Co.sub.15Nb.sub.2 SiON 15 54 4906 0.204 0.291 0.892 0.03 0.02 1.90 OK Example 147 Fe.sub.15Co.sub.83Cu.sub.2 SiON 15 54 4954 0.224 0.312 0.814 0.08 0.04 1.84 OK Example 148 Fe.sub.44Co.sub.54Cu.sub.2 SiON 15 54 4967 0.214 0.302 0.838 0.06 0.03 1.98 OK Example 149 Fe.sub.59Co.sub.39Cu.sub.2 SiON 15 54 4923 0.208 0.296 0.887 0.04 0.02 2.14 OK Example 150 Fe.sub.83Co.sub.15Cu.sub.2 SiON 15 54 4898 0.200 0.287 0.899 0.03 0.01 2.00 OK Example 151 Fe.sub.15Co.sub.83P.sub.2 SiON 15 54 4883 0.222 0.310 0.812 0.09 0.05 1.90 OK Example 152 Fe.sub.44Co.sub.54P.sub.2 SiON 15 54 4892 0.212 0.300 0.834 0.07 0.03 1.93 OK Example 153 Fe.sub.59Co.sub.39P.sub.2 SiON 15 54 4856 0.206 0.294 0.882 0.04 0.02 2.12 OK Example 154 Fe.sub.83Co.sub.15P.sub.2 SiON 15 54 4814 0.199 0.285 0.894 0.03 0.02 1.94 OK Example 155 Fe.sub.15Co.sub.83Ni.sub.2 SiON 15 54 4932 0.224 0.312 0.815 0.08 0.04 1.89 OK Example 156 Fe.sub.44Co.sub.54Ni.sub.2 SiON 15 54 4970 0.215 0.304 0.839 0.06 0.03 2.04 OK Example 157 Fe.sub.59Co.sub.39Ni.sub.2 SiON 15 54 4917 0.208 0.295 0.888 0.04 0.02 2.22 OK Example 158 Fe.sub.83Co.sub.15Ni.sub.2 SiON 15 54 4931 0.199 0.285 0.901 0.03 0.01 2.12 OK Example 159 Fe.sub.15Co.sub.83Ni.sub.2 SiON 45 54 5024 0.233 0.320 0.808 0.08 0.05 1.67 OK Example 160 Fe.sub.44Co.sub.54Ni.sub.2 SiON 45 54 5035 0.223 0.311 0.831 0.06 0.03 1.74 OK Example 161 Fe.sub.59Co.sub.39Ni.sub.2 SiON 45 54 5104 0.215 0.303 0.879 0.04 0.02 1.88 OK Example 162 Fe.sub.83Co.sub.15Ni.sub.2 SiON 45 54 5166 0.205 0.293 0.892 0.03 0.02 1.83 OK

[0151] According to Table 10-4, even with the varied composition of the first phases and/or the varied compound contained in the second phase, the MX-rich CV of the nanogranular magnetic films was larger than the MX-poor CV thereof, and the simple figure of merit was good. If three Comparative Examples corresponding to each Example were prepared to calculate the figure of merit, it would be highly probable that the calculated figure of merit would be 1.20 or more.

Experiment 8-5

[0152] Examples 163 to 170 were carried out as in Examples 155 to 158 except that the ratio of Fe to Co in the first phases was changed. Examples 171 to 174 were carried out as in Examples 155 to 158 except that the number of additional element chips was changed. Further, Examples 175 to 184 were carried out as in Example 156 except that the additional element was changed. Table 10-5 shows the results.

TABLE-US-00014 TABLE 10-5 Evaluation of figure of merit Magnetic film Simple First Second Experimental benchmark Simple phases phase N/ V.sub.1/ Film CV specific specific figure OK/ Sample Atomic Atomic (N + 0) (V.sub.1 + V.sub.2) thickness MX- MX- Bs resistance resistance of Not No. ratio ratio Atom % % nm poor rich T cm cm merit OK Example 163 Fe.sub.15Co.sub.83Ni.sub.2 SiON 15 52 5176 0.217 0.305 0.803 0.120 0.051 2.34 OK Example 164 Fe.sub.44Co.sub.54Ni.sub.2 SiON 15 52 5202 0.208 0.295 0.829 0.088 0.036 2.45 OK Example 165 Fe.sub.59Co.sub.39Ni.sub.2 SiON 15 52 5169 0.202 0.289 0.870 0.056 0.021 2.68 OK Example 166 Fe.sub.83Co.sub.15Ni.sub.2 SiON 15 52 5194 0.194 0.279 0.881 0.045 0.018 2.47 OK Example 155 Fe.sub.15Co.sub.83Ni.sub.2 SiON 15 54 4932 0.224 0.312 0.815 0.082 0.043 1.89 OK Example 156 Fe.sub.44Co.sub.54Ni.sub.2 SiON 15 54 4970 0.215 0.304 0.839 0.064 0.031 2.04 OK Example 157 Fe.sub.59Co.sub.39Ni.sub.2 SiON 15 54 4917 0.208 0.295 0.888 0.037 0.017 2.22 OK Example 158 Fe.sub.83Co.sub.15Ni.sub.2 SiON 15 54 4931 0.199 0.285 0.901 0.030 0.014 2.12 OK Example 167 Fe.sub.15Co.sub.83Ni.sub.2 SiON 15 60 5046 0.250 0.334 0.890 0.027 0.016 1.66 OK Example 168 Fe.sub.44Co.sub.54Ni.sub.2 SiON 15 60 5083 0.232 0.319 0.922 0.019 0.011 1.74 OK Example 169 Fe.sub.59Co.sub.39Ni.sub.2 SiON 15 60 5037 0.224 0.312 0.964 0.013 0.0066 2.02 OK Example 170 Fe.sub.83Co.sub.15Ni.sub.2 SiON 15 60 5020 0.216 0.304 0.971 0.011 0.0061 1.83 OK Example 171 Fe.sub.14Co.sub.81Ni.sub.5 SiON 15 54 4826 0.235 0.322 0.807 0.077 0.049 1.58 OK Example 172 Fe.sub.43Co.sub.52Ni.sub.5 SiON 15 54 4795 0.226 0.314 0.829 0.061 0.036 1.70 OK Example 173 Fe.sub.57Co.sub.38Ni.sub.5 SiON 15 54 4802 0.215 0.304 0.878 0.034 0.019 1.80 OK Example 174 Fe.sub.81Co.sub.14Ni.sub.5 SiON 15 54 4818 0.206 0.294 0.890 0.028 0.016 1.73 OK Example 175 Fe.sub.44Co.sub.54Mo.sub.2 SiON 15 54 4923 0.216 0.304 0.828 0.064 0.036 1.76 OK Example 176 Fe.sub.44Co.sub.54Ti.sub.2 SiON 15 54 4874 0.215 0.304 0.839 0.061 0.031 1.95 OK Example 177 Fe.sub.44Co.sub.54Zr.sub.2 SiON 15 54 4864 0.215 0.304 0.830 0.063 0.035 1.77 OK Example 178 Fe.sub.44Co.sub.54Cr.sub.2 SiON 15 54 4912 0.217 0.305 0.836 0.064 0.033 1.96 OK Example 179 Fe.sub.44Co.sub.54Mn.sub.2 SiON 15 54 4965 0.215 0.303 0.832 0.063 0.035 1.82 OK Example 180 Fe.sub.44Co.sub.54B.sub.2 SiON 15 54 5034 0.208 0.296 0.837 0.067 0.032 2.08 OK Example 181 Fe.sub.44Co.sub.54C.sub.2 SiON 15 54 5078 0.205 0.293 0.833 0.067 0.034 1.96 OK Example 182 Fe.sub.44Co.sub.54V.sub.2 SiON 15 54 5019 0.218 0.306 0.835 0.066 0.033 1.98 OK Example 183 Fe.sub.44Co.sub.54W.sub.2 SiON 15 54 4912 0.217 0.305 0.835 0.063 0.033 1.91 OK Example 184 Fe.sub.44Co.sub.54Al.sub.2 SiON 15 54 4864 0.212 0.300 0.832 0.062 0.035 1.79 OK

[0153] According to Table 10-5, even with the varied composition of the first phases, the MX-rich CV of the nanogranular magnetic films was larger than the MX-poor CV thereof, and the simple figure of merit was good. If three Comparative Examples corresponding to each Example were prepared to calculate the figure of merit, it would be highly probable that the calculated figure of merit would be 1.20 or more.

Experiment 9

[0154] Experiment 9 was conducted as in Examples 3, 103, and 134 except that the film thickness was greatly changed. In Experiment 9, the simple figure of merit was calculated on the supposition that, even if the film thickness was greatly different from 5,000 nm, the film thickness was about 5,000 nm. Table 11 shows the results.

TABLE-US-00015 TABLE 11 Film formation conditions Contin- Contin- uously uous formed Magnetic film Preprocessing film film First Second Reverse Rotation formation thick- phases phase N/ V.sub.1/ Sample sput- speed time ness Atomic Atomic (N + 0) (V.sub.1 + V.sub.2) No. UV/O.sub.3 tering rpm s nm ratio ratio Atom % % Example Yes Yes 12 1.7 1.0 Fe.sub.45Co.sub.55 SiO.sub.2 0 46 69 Example Yes Yes 12 1.7 1.0 Fe.sub.45Co.sub.55 SiO.sub.2 0 46 3 Example Yes Yes 12 1.7 1.0 Fe.sub.45Co.sub.55 SiO.sub.2 0 46 70 Example Yes Yes 12 1.7 1.0 Fe.sub.45Co.sub.55 SiO.sub.2 0 46 71 Example Yes Yes 12 1.7 1.0 Fe.sub.45Co.sub.55 SiO.sub.2 0 54 185 Example Yes Yes 12 1.7 1.0 Fe.sub.45Co.sub.55 SiO.sub.2 0 54 103 Example Yes Yes 12 1.7 1.0 Fe.sub.45Co.sub.55 SiO.sub.2 0 54 186 Example Yes Yes 12 1.7 1.0 Fe.sub.45Co.sub.55 SiON 45 54 187 Example Yes Yes 12 1.7 1.0 Fe.sub.45Co.sub.55 SiON 45 54 134 Example Yes Yes 12 1.7 1.0 Fe.sub.45Co.sub.55 SiON 45 54 188 Evaluation of figure of merit Simple Magnetic film Experi- bench- Film mental mark Simple thick- CV specific specific figure OK/ Sample ness MX- MX- Bs resistance resistance of Not No. nm poor rich T cm cm merit OK Example 299 0.190 0.273 0.668 1.13 0.40 2.80 OK 69 Example 4,876 0.191 0.275 0.667 1.16 0.41 2.83 OK 3 Example 20,462 0.198 0.284 0.661 1.18 0.45 2.60 OK 70 Example 101,293 0.207 0.294 0.653 1.21 0.52 2.32 OK 71 Example 277 0.208 0.295 0.847 0.065 0.028 2.30 OK 185 Example 4,739 0.208 0.296 0.848 0.067 0.028 2.40 OK 103 Example 25,763 0.215 0.303 0.840 0.068 0.031 2.19 OK 186 Example 283 0.227 0.314 0.831 0.057 0.035 1.63 OK 187 Example 5,026 0.231 0.318 0.833 0.058 0.034 1.70 OK 134 Example 25,238 0.238 0.324 0.835 0.056 0.033 1.69 OK 188

[0155] According to Table 11, even with the greatly varied film thickness, the MX-rich CV of the nanogranular magnetic films was larger than the MX-poor CV thereof, and the simple figure of merit was good. If three Comparative Examples corresponding to the film thickness of each Example were prepared to calculate the figure of merit, it would be highly probable that the calculated figure of merit would be 1.20 or more.

[0156] According to the above Examples and the like, the smaller the amount of the additional element added, the more readily both Bs and specific resistance were absolutely increased. In terms of absolutely increasing both Bs and specific resistance, the figure of merit calculated using y=0.0044x.sup.11.25, which was the formula for the performance curve derived from Comparative Examples 2 to 4 not containing an additional element, was more preferably 1.20 or more.

REFERENCE NUMERALS

[0157] 1 . . . nanogranular magnetic film [0158] 11 . . . first phase [0159] 12 . . . second phase [0160] 111 . . . rotation member [0161] 111a . . . rotation plate [0162] 111b . . . rotation axis [0163] 113 . . . substrate [0164] 121 . . . sputtering apparatus [0165] 123 . . . sputtering target [0166] 131 . . . shutter