JOINED BODY OF JOINING BASE MATERIAL AND METAL LAYER

Abstract

A joined body of a joining base material and a metal layer which, when the metal layer is joined to the base material, adhesion of the metal layer is high, variation in adhesion is small, and the joining can be performed inexpensively. The metal layer is joined to the joining base material via an intermediate layer coating formed on a joint surface of the base material. The intermediate layer coating is fused to the joint surface of the base material, and an anchor forming material that joins the metal layer by an anchor effect is dispersed and embedded in the intermediate layer coating; the anchor forming material partially protrudes outward from the intermediate layer coating, and is fused to the intermediate layer coating; and the metal layer is joined to a surface of the intermediate layer coating and a surface of the anchor forming material protruding outward from the intermediate layer coating.

Claims

1. A joined body of a joining base material and a metal layer, the metal layer being joined to a joint surface of the joining base material via an intermediate layer coating, wherein in the intermediate layer coating, an anchor forming material that forms an anchor for joining the metal layer by an anchor effect is dispersed and embedded, and the intermediate layer coating is fused to the joint surface of the joining base material, the embedded anchor forming material partially protrudes outward from the intermediate layer coating, and is fused to the intermediate layer coating, and the metal layer is joined to a surface of the intermediate layer coating and a surface of the anchor forming material protruding outward from the intermediate layer coating.

2. The joined body of a joining base material and a metal layer according to claim 1, wherein the intermediate layer coating is a fusion layer including one or two or more kinds of metal components, or is oxide glass produced by melting a compound of the metal components.

3. The joined body of a joining base material and a metal layer according to claim 1, wherein the intermediate layer coating includes a fusing agent in which the anchor forming material is mixed and dispersed, the fusing agent being fused to the joint surface of the joining base material.

4. The joined body of a joining base material and a metal layer according to claim 3, wherein the fusing agent includes one or two or more kinds of metal components, or a compound component of the metal components.

5. The joined body of a joining base material and a metal layer according to claim 1, wherein the anchor forming material is one kind or a mixture of two or more kinds of oxide powder, carbide powder, nitride powder, boride powder, silicide powder, diatomaceous earth powder, silica gel powder, glass powder, diamond powder, DLC powder, ceramic powder, porcelain powder, silica fiber powder, ceramic fibers, mica powder, graphite powder, kaolin powder, metal powder particles, fibers, and whiskers.

6. The joined body of a joining base material and a metal layer according to claim 1, wherein the anchor forming material has a diameter of 0.01 to 30 μm.

7. The joined body of a joining base material and a metal layer according to claim 1, wherein the anchor forming material has a spherical, angular, or polygonal shape, and the anchor forming material is dispersed and embedded in a fibrous form in which a plurality of the anchor forming materials are bonded to each other, or in a mesh form in which the anchor forming materials overlap each other.

8. The joined body of a joining base material and a metal layer according to claim 1, wherein the joining base material is any of Al.sub.2O.sub.3, AlN, Si.sub.3N.sub.4, BN, SiC, ZrC, WC, DLC, diamond, silicon wafer, sapphire, ceramic, porcelain, GaC, GaAs, GaN, GaO, LED, and graphite.

9. The joined body of a joining base material and a metal layer according to claim 1, wherein the joining base material has any of a plate shape, a column shape, a spherical shape, a cylindrical shape, or a bar shape.

10. The joined body of a joining base material and a metal layer according to claim 1, wherein the metal layer has a structure in which a primary metal layer is formed on the intermediate layer coating, and a secondary metal layer is formed on the primary metal layer.

11. The joined body of a joining base material and a metal layer according to claim 10, wherein a coating metal of the primary metal layer includes one or two or more kinds of metals.

12. The joined body of a joining base material and a metal layer according to claim 10, wherein the primary metal layer has a thickness of 0.001 to 10 μm.

13. The joined body of a joining base material and a metal layer according to claim 10, wherein a coating metal of the secondary metal layer is a laminate of one or two or more kinds of metals, or an alloy of two or more kinds of metals.

14. The joined body of a joining base material and a metal layer according to claim 10, wherein the secondary metal layer has a thickness of 0.1 μm to 10 cm.

15. The joined body of a joining base material and a metal layer according to claim 1, wherein the joining base material is a ceramic substrate, and one of a circuit and a pad or both are formed on the ceramic substrate.

16. The joined body of a joining base material and a metal layer according to claim 15, wherein a surface of a secondary metal layer in one of the circuit and the pad or both is plated with any of Ni, Sn, Pd, Ag, Au, Pt, Pb, Ni/Pd/Au, Ni/Sn, Ni—Sn—Ag—Cu, Sn—Bi, and Sn—Cu.

17. The joined body of a joining base material and a metal layer according to claim 1, wherein an electronic component is joined to and mounted on the metal layer.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0084] FIG. 1 is a schematic diagram for explaining relations among a joining base material, an intermediate layer coating, anchor forming materials, and metal layers (a primary metal layer and a secondary metal layer).

[0085] FIG. 2 is a picture of anchor forming materials firmly adhering to a ceramic (after the formation of a primary metal layer).

DESCRIPTION OF EMBODIMENTS

[0086] Hereinafter, embodiments of the present invention will be described by putting the embodiments in contrast with conventional methods. Note that the present embodiments will be specifically described for the purpose of making the spirit of the present invention easier to understand, and of course, the present invention is not limited to the embodiments.

EXAMPLE 1

[0087] A 99% alumina ceramic plate was used as a joining base material. [0088] (1) In accordance with a conventional method, the alumina ceramic plate was degreased, pickled, and etched, and then dried. [0089] (2) Water was added to 50 g of a SiO.sub.2 anchor forming material having an average particle diameter of 0.5 to 1.0 μm, 20 g of sodium tungstate, 30 g of vanadium sulfate, and 20 g of boric acid to produce 1 L of a solution, and the solution was stirred for 5 hours to prepare a fusing agent containing the anchor forming material for forming a fusion layer to be serve as an intermediate layer coating. [0090] (3) This fusing agent was applied to the alumina ceramic plate prepared at (1) by spraying. [0091] (4) The plate was air-dried for 5 hours. [0092] (5) Using an electric furnace, the plate was heated at 1000° C. for 2 hours. [0093] (6) SiO.sub.2 particles were fused to the alumina plate (see FIG. 2). [0094] (7) To obtain a primary metal layer, in accordance with a conventional method, the plate was subjected to sensitizer-activator treatment and coated with 2 μm of electroless copper plating. [0095] (8) To obtain a secondary metal layer, in accordance with a conventional method, the plate was electroplated with copper sulfate to attain 30-μm-thick copper layer. [0096] (9) The plate was subjected to heat treatment at 500° C. for 30 minutes in an atmosphere of N.sub.2. [0097] (10) A dry film was stuck on the plate, and a circuit and a pad were formed thereon by photolithography. [0098] (11) Subsequently, electroless Ni—Pd—Au plating was applied only to a portion on which a semiconductor element was mounted. [0099] (12) A heat sink for power semiconductors was produced. [0100] (13) Adhesion strength between the alumina ceramic plate and the copper plating was measured at three points.

[0101] The peel strength was 2.5 to 2.3 kg/cm. Note that, when the peel strength was 1.0 kg/cm or more, the plate can be used as a substrate for power semiconductors.

[0102] For comparison, the peel strength of a plate produced not through the step of forming a fusion layer of the present invention, but through other steps identical to the steps according to the present invention was also measured at three points, and as a result, the peel strength was 0.1 to 0.05 kg/cm, which meant that the copper plating did not adhere the alumina ceramic plate at all.

[0103] It was confirmed that, in the present example, adhesion was remarkably enhanced.

EXAMPLE 2

[0104] A silicon nitride substrate was used as a joining base material. [0105] (1) In accordance with a conventional method, the silicon nitride substrate was degreased, pickled, and etched, and then dried. Subsequently, a surface of the substrate was roughened by honing to achieve approximately Ra 0.2 μm. [0106] (2) Water was added to 50 g of a SiC anchor forming material having an average particle diameter of 0.5 to 1.5 μm, 10 g of CaCl.sub.2, 50 g of SnSO.sub.4, 50 g of TiSO.sub.4, and 50 g of sodium silicate to produce 1 L of a solution, and the solution was stirred for 5 hours to prepare a fusing agent for forming a fusion layer. [0107] (3) Using a spin coater, this fusing agent was applied to the silicon nitride substrate prepared at (1). [0108] (4) The substrate was air-dried for 5 hours, and then heated at 800° C. for 2 hours and at 1100° C. for 2 hours. [0109] (5) SiC particles were fused to the silicon nitride substrate. [0110] (6) To obtain a primary metal layer, in accordance with a conventional method, the substrate was subjected to sensitizer-activator treatment to be electroless-plated with 1 μm of Ni—B. [0111] (7) Subsequently, to obtain a secondary metal layer, in accordance with a conventional method, the substrate was electroplated with 50 μm of copper by using copper sulfate. [0112] (8) Adhesion strength was measured at three points in the same manner as in Example 1, and as a result, the peel strength was 2.5 to 2.4 kg/cm. [0113] (9) In this substrate, using photolithography, a circuit and a pad were formed, and then the substrate was plated with 0.2 μm of Pd, and furthermore plated with 0.01 μm of Au, and then a SiC-based power transistor was mounted thereon.

[0114] For comparison, the peel strength of a substrate produced not through the step of forming the fusion layer of the present example, but through other steps identical to the steps according to the present example was measured at three points, and as a result, the peel strength was 0.1 to 0.01 kg/cm, which meant that the metal layers did not adhere the substrate at all.

[0115] It was confirmed that, in the present example, the adhesion was remarkably enhanced.

EXAMPLE 3

[0116] An AlN substrate was used as a joining base material. [0117] (1) In accordance with a conventional method, the AlN substrate (trade name: SHAPAL, manufactured by Tokuyama Corporation) was degreased, pickled, and etched, and then dried. [0118] (2) Water was added to, as an anchor forming material, 50 g of BN particles having a particle diameter of 0.5 to 1.5 μm, 50 g of sodium molybdate, 10 g of titanium sulfate, and 50 g of kaolin to produce 1 L of a solution, and the solution was stirred for 5 hours to prepare a fusing agent for forming a fusion layer. [0119] (3) A dry film was stuck on the AlN substrate prepared at (1), and by photolithography, openings were produced in portions for a circuit and a pad. [0120] (4) The fusing agent prepared at (2) was sprayed so that the fusing agent remains only in the openings and the substrate was air-dried. [0121] (5) Using an electric furnace, the substrate was heated at 200° C. for 1 hour to remove the fusing agent remaining on the dry film, and then heated at 1100° C. for 3 hours. The BN particles were fused only to the openings. [0122] (6) To obtain a primary metal layer, the substrate was subjected to sensitizer-activator treatment, and electroless-plated with 3 μm of copper. At this point, copper plating was deposited on the whole surface of the substrate. [0123] (7) To leave the copper plating only in the openings, once a tape was stuck on the whole surface, and then the tape was removed therefrom, and as a result, the copper plating did not adhere tightly on portions to which the anchor forming material did not firmly adhere, other than the openings, the copper plating was peeled off and the plating remained only in the openings. [0124] (8) To obtain a secondary metal layer, the substrate was electroless-plated with 20 μm of copper. [0125] (9) The substrate was subjected to heat treatment at 450° C. for 30 minutes in the atmosphere. [0126] (10) The adhesion strength was measured at three points, and as a result, the peel strength was 2.6 to 2.5 kg/cm.

[0127] For comparison, the peel strength of a portion, without any anchor forming material, of the AlN substrate was measured at three points, and as a result, the peel strength was 0.1 to 0.05 kg/cm.

EXAMPLE 4

[0128] Sapphire (99.99% Al.sub.2O.sub.3) was used as a joining base material. [0129] (1) In accordance with a conventional method, a sapphire substrate was degreased and etched, and then dried. [0130] (2) Water was added to, as an anchor forming material, 30 g of a Pyrex glass powder having a particle diameter of 0.3 to 1.5 μm, 50 g of ferrous ammonium sulfate, 20 g of MoO.sub.3, 20 g of H.sub.3BO.sub.3, 1 g of AgNO.sub.3, and 5 g of a silane coupling agent A-1100 to produce 1 L of a solution, and the solution was stirred for 5 hours to prepare a fusing agent containing the anchor forming material for forming a fusion layer. [0131] (3) The fusing agent prepared at (2) was applied to the sapphire substrate prepared at (1) by spraying. [0132] (4) The substrate was air-dried, and then heated at 700° C. for 2 hours and at 1100° C. for 2 hours.
Glass particles were fused to the sapphire substrate. [0133] (5) To obtain a primary metal layer, 0.5 μm of Ti and 2 μm of Cu were deposited on the whole surface of the sapphire substrate by ion plating to coat the whole surface. [0134] (6) Subsequently, to obtain a secondary metal layer, the substrate was plated with 30 μm of copper sulfate. The adhesion strength was measured at three points, and as a result, the peel strength was 1.8 to 1.7 kg/cm.

[0135] For comparison, the peel strength of a substrate produced not through the step of fusing the anchor forming material according to the present example, but through other steps identical to the steps according to the present example was measured at three points, and as a result, the peel strength was 0.3 to 0.1 kg/cm, and hence the comparative substrate was not able to be used for a substrate for mounting electronic components thereon.

EXAMPLE 5

[0136] A commercially available SiC plate was used as a joining base material. [0137] (1) In accordance with a conventional method, the SiC plate was degreased and etched, and then dried. [0138] (2) Water was added to, as an anchor forming material, 30 g of commercially available SiC particles having a particle diameter of 0.3 to 1.5 μm, 50 g of glaze (SK-12, glaze for pottery), 20 g of AgNO.sub.3, 10 g of EDTA-Cu, 5 g of titanium sulfate, and 20 g of B.sub.2O.sub.3 to produce 1 L of a solution, and the solution was stirred for 5 hours to prepare a fusing agent containing the anchor forming material. [0139] (3) This fusing agent was uniformly applied to the SiC plate prepared at (1) by spraying, and then the substrate was air-dried for 10 hours. [0140] (4) Using an electric furnace, the substrate was heated at 1300° C. for 3 hours. [0141] (5) SiC particles were uniformly fused to the SIC plate. [0142] (6) To obtain a primary metal layer, in accordance with a conventional method, the plate was subjected to sensitizer-activator treatment, and the whole surface of the plate was electroless-plated with 1.0 to 1.5 μm of Ni—B. [0143] (7) A dry film was stuck on the plate and the plate was subjected to treatment by photolithography so that openings were formed only in a circuit and a pad, and then the pad and the circuit were coated with 30 μm plating by using a copper sulfate plating bath to form a secondary metal layer. [0144] (8) After the dry film was peeled off, portions other than portions for the circuit and the pad were removed by quick etching.  This is a circuit formation method according to what is called SAP (Semi Additive Process).  The adhesion strength of the circuit was measured at three points, and as a result, the peel strength was 1.9 to 1.8 kg/cm.

[0145] For comparison, the adhesion strength of a plate produced not through the step of firmly adhering the anchor forming material according to the present example, but through other steps identical to the steps according to the present example was measured at three points, and as a result, the peel strength was 0.3 to 0.1 kg/cm, which meant that the substrate with such strength was not able to be put to practical use.

EXAMPLE 6

[0146] A commercially available WC plate was used as a joining base material. [0147] (1) In accordance with a conventional method, the WC plate was degreased and etched, and then dried. [0148] (2) Water was added to, as an anchor forming material, 30 g of SiC particles having a particle diameter of 0.5 to 1.5 μm, 10 g of a silane coupling agent A-1100, 50 g of vanadium sulfate, 50 g of commercially available glaze (SK-9), and 10 g of water glass to produce 1 L of a solution, and the solution was stirred for 5 hours to prepare a fusing agent containing the anchor forming material. [0149] (3) This fusing agent was uniformly applied to the WC plate prepared at (1) by a spin coater. Subsequently, the plate was air-dried for 10 hours. [0150] (4) Using an electric furnace, the plate was heated at 1200° C. for 3 hours. [0151] (5) SiC particles were uniformly fused to the WC plate. [0152] (6) To form a primary metal layer, the plate was coated with 1.0 μm of copper by sputtering. Subsequently, the plate was electroplated with 50 μm of copper (a secondary metal layer). [0153] (7) The plate was subjected to heat treatment at 400° C. for 30 minutes in an atmosphere of N.sub.2+H.sub.2. [0154] (8) The adhesion strength was measured at three points, and as a result, the peel strength was 2.9 to 2.4 kg/cm.

[0155] For comparison, the adhesion strength of a plate produced without the treatment according to the present example was measured at three points, and as a result, the peel strength was approximately 0.1 to 0.03 kg/cm, and accordingly the peeling-off was easily made in a tape-peeling test.

EXAMPLE 7

[0156] A commercially available AlN substrate (SHAPAL) was used as a joining base material. [0157] (1) In accordance with a conventional method, the AlN substrate was degreased and etched, and then dried. [0158] (2) Water was added to, as an anchor forming material, 60 g of Ni fine particles having an average particle diameter of 1.5 μm, 50 g of MoO.sub.3, 10 g of B.sub.2O.sub.3, and 50 g of a silane coupling agent (A-1100) to produce 1 L of a solution.

[0159] The solution was stirred for 5 hours to prepare a fusing agent containing the anchor forming material for forming a fusion layer. [0160] (3) A dry film was stuck on the whole surface of the AlN substrate, and the substrate was subjected to treatment by photolithography so that openings were respectively formed only in portions for a circuit and a pad. [0161] (4) The fusing agent prepared at (2) was applied only to the openings. [0162] (5) After air-dried, the substrate was heated using an electric furnace at 1100° C. for 2 hours. [0163] (6) After the substrate was subjected to sensitizer-activator treatment, the whole surface of the substrate was electroless-plated with 3 μm of copper. [0164] (7) The substrate was subjected to treatment by photolithography in the same manner as that at the step (3) so that the circuit and the pad became openings. [0165] (8) Only the pad and the circuit were electroplated with 20 μm of copper and furthermore electroplated with Ni—Pd—Au thereon. Subsequently, after photoresist was removed, thin copper plating film present in a portion other than the circuit and the pad was peeled off (SAP) to prepare a plating substrate in which only the pad and the circuit remain, and a power transistor was mounted on the pad. [0166] (9) The adhesion strength was measured, and as a result, the peel strength was 2.7 to 2.5 kg/cm.

[0167] For comparison, the adhesion strength of a substrate in the absence of the anchor forming material was measured, and as a result, the peel strength was 0.1 to 0.01 kg/cm.

EXAMPLE 8

[0168] A commercially available SiC substrate was used as a joining base material. [0169] (1) In accordance with a conventional method, the SiC substrate was degreased and etched, and then dried. [0170] (2) Water was added to, as an anchor forming material, 60 g of SiC fibers having a diameter of 1.0 μm and a length of 4 to 5 μm, 50 g of water glass, 50 g of ammonium molybdate, 50 g of vanadium oxide, and 5 g of boric acid to produce 1 L of a solution, and the solution was stirred for 3 hours to prepare a fusing agent for forming a fusion layer. [0171] (3) This fusing agent was applied to the SiC substrate prepared at (1) by showering. [0172] (4) After air-dried, the substrate was heated at 1100° C. for 3 hours. The SiC fibers were deposited in a mesh form and adhered to each other. [0173] (5) Using a well-known method, the substrate was electroless-plated with 3 μm of copper and then plated with 30 μm of copper sulfate. The adhesion strength was measured at three points, and as a result, the peel strength was 2.8 to 2.6 kg/cm.

[0174] In contrast, the adhesion strength of a substrate to which the fusing agent according to the present invention was not applied was measured at three points, and as a result, the peel strength was 0.1 to 0.01 kg/cm.

[0175] In Examples 1 to 8 described above, it was confirmed that the adhesion strength according to the present invention was several times to several tens of times higher than the adhesion strength in the case where the fusion layer serving as the intermediate layer coating according to the present invention was not formed (that is, in the case of conventional plating), and furthermore, variation in the adhesion strength was much smaller.

EXAMPLE 9

[0176] Using an Al.sub.2O.sub.3 substrate having a size of 100 mm×80 mm×thickness 0.3 mm, comparisons of adhesion strength and variation thereof with a conventional method were made.

[0177] As the conventional method, there was employed a method in which the substrate was immersed in a strong-alkaline molten salt and a surface of the substrate was etched and plated.

[0178] A test was performed in such a manner that a pad having a size of 2 mm×2 mm was formed on a surface of the Al.sub.2O substrate, and a wire was soldered thereto, and the adhesion strength (pull strength) was measured by vertical pulling.

[0179] 0.5 μm of electroless Cu plating was applied to form a primary metal layer, and 40 μm of Cu electroplating was applied to form a secondary metal layer. To enhance solderability, 0.1 μm of electroless Au plating was applied onto the Cu.

[0180] The number of measurement points was 10 points.

[0181] Table 1 lists tensile test results.

TABLE-US-00001 TABLE 1 1 2 3 4 5 6 7 8 9 10 Present 4.3 4.8 4.0 3.7 4.4 4.2 4.0 3.9 4.4 4.2 Example Comparative 3.8 5.2 1.0 4.1 3.0 3.6 2.2 3.1 0.8 4.2 Example

[0182] The results listed in Table 1 reveal that the present example (using the same method as that in Example 3) exhibits higher tensile strength and extremely smaller variation in tensile strength. In contrast, the results reveal that, in a comparative example using the conventional method, the tensile strength is considerably high, but, variation in the tensile strength is large. It was confirmed that, compared with than the conventional technique, the present invention exhibited higher tensile strength and extremely smaller variation in the tensile strength.

[0183] Tables 2 to 21 respectively illustrate Examples 10 to 29 in which different combinations of the ceramic base material, the anchor forming material, and the fusing component are employed.

[0184] In the tables, Comparative Example indicates peel strength according to the conventional technique in the case of not applying the fusing agent.

[0185] In the tables, peel strength indicates the results of three-point measurements of the present invention and the comparative example, as in the case of Examples 1 to 8.

[0186] In Examples 10 to 29, pretreatment of a joining base material and application of a fusing agent were performed in the same manner as in Examples 1 to 8. Furthermore, after secondary plating, in the present examples and comparative examples, peel strength was measured after 30-minute heat treatment at 400° C. in an atmosphere of N.sub.2.

EXAMPLE 10

[0187] Table 2 lists results.

EXAMPLE 11

[0188] Table 3 lists results.

EXAMPLE 12

[0189] Table 4 lists results.

EXAMPLE 13

[0190] Table 5 lists results.

EXAMPLE 14

[0191] Table 6 lists results.

EXAMPLE 15

[0192] Table 7 lists results.

EXAMPLE 16

[0193] Table 8 lists results.

EXAMPLE 17

[0194] Table 9 lists results.

EXAMPLE 18

[0195] Table 10 lists results.

EXAMPLE 19

[0196] Table 11 lists results.

EXAMPLE 20

[0197] Table 12 lists results.

EXAMPLE 21

[0198] Table 13 lists results.

EXAMPLE 22

[0199] Table 14 lists results.

EXAMPLE 23

[0200] Table 15 lists results.

EXAMPLE 24

[0201] Table 15 lists results.

EXAMPLE 25

[0202] Table 17 lists results.

EXAMPLE 26

[0203] Table 18 lists results.

EXAMPLE 27

[0204] Table 18 lists results.

EXAMPLE 28

[0205] Table 19 lists results.

EXAMPLE 29

[0206] Table 20 lists results.

TABLE-US-00002 TABLE 2 Joining Anchor Components of Fusing Primary Metal Layer Base Forming Agent and Concentration Sintering Condition and Secondary Metal Adhesion Strength Material Material (g/L) of Each Component Temperature × Time Layer kg/cm WC SiO.sub.2 Sodium Silicate: 20 1200° C. × 3 hours Primary: Ni—B 2.7-2.4 0.5-1.5 μm Ammonium Molybdate: 50 1.0 μm Comparative 50 g/L Boric Acid: 50 Secondary: Cu Example: Copper Sulfate: 20 30 μm 0.5-0.1 Water: Remainder

TABLE-US-00003 TABLE 3 Joining Anchor Components of Fusing Primary Metal Layer Base Forming Agent and Concentration Sintering Condition and Secondary Metal Adhesion Strength Material Material (g/L) of Each Component Temperature × Time Layer kg/cm DLC BN Antimony Sulfate: 30 1000° C. × 2 hours Primary: Cu 2.0-2.0  0.5-1.5 μm Manganese Sulfate: 20 1.0 μm Comparative 30 g/L Indium Sulfate: 30 Secondary: Cu Example: Silver Chloride: 30 40 μm 1.0-0.01 Water: Remainder

TABLE-US-00004 TABLE 4 Primary Metal Joining Anchor Components of Fusing Agent Layer and Base Forming and Concentration (g/L) of Sintering Condition Secondary Metal Adhesion Strength Material Material Each Component Temperature × Time Layer kg/cm Porcelain TiO.sub.2 Glaze (SK-12): 50 1000° C. × 3 hours Primary: Cu 2.5-2.2  0.5-2.0 μm AgNO.sub.3: 50 2.0 μm Comparative 50 g/L Zirconium Sulfate: 50 Secondary: Cu Example: Water: Remainder 20 μm 1.0-0.01

TABLE-US-00005 TABLE 5 Primary Metal Joining Anchor Components of Fusing Agent Layer and Base Forming and Concentration (g/L) of Sintering Condition Secondary Metal Adhesion Strength Material Material Each Component Temperature × Time Layer kg/cm AlN Pyrex Glass Molybdenum Oxide: 20 1100° C. × 4 hours Primary: Ni—P 2.7-2.4 (SHAPAL) Powder Boric Acid: 10 2.0 μm Comparative Particle Vanadium Sulfate: 10 Secondary: Cu Example: Diameter: Silane Coupling Agent (A-1100): 5 40 μm 0.6-0.2 0.1-3.0 μm Water: Remainder 10 g/L

TABLE-US-00006 TABLE 6 Primary Metal Joining Anchor Components of Fusing Agent Layer and Adhesion Base Forming and Concentration (g/L) of Sintering Condition Secondary Metal Strength Material Material Each Component Temperature × Time Layer kg/cm Si.sub.3N.sub.4 BN Silver Nitrate: 10 1300° C. × 3 hours Primary: Cu 2.6-2.3  Particle Thallium Sulfate: 50 2.0 μm Comparative Diameter: Sodium Silicate: 20 Secondary: Cu Example: 0.5-1.5 μm Borax: 20 30 μm 0.1-0.01 60 g/L Water: Remainder

TABLE-US-00007 TABLE 7 Primary Metal Joining Anchor Components of Fusing Agent Layer and Adhesion Base Forming and Concentration (g/L) Sintering Condition Secondary Metal Strength Material Material of Each Component Temperature × Time Layer kg/cm SiC SiO.sub.2 Particle Copper Sulfate: 50 1400° C. × 3 hours Primary: Ni—B 2.4-2.0 Diameter: Titanium Sulfate: 50 1.0 μm Comparative 0.5-1.5 μm Silver Nitrate: 30 Secondary: Cu Example: 50 g/L Water: Remainder 30 μm 0.1-0.01

TABLE-US-00008 TABLE 8 Primary Metal Joining Anchor Components of Fusing Agent Layer and Adhesion Base Forming and Concentration (g/L) Sintering Condition Secondary Metal Strength Material Material of Each Component Temperature × Time Layer kg/cm BN BN Particle Sodium Molybdate: 10 1000° C. × 4 hours Primary: Cu 2.9-2.7 Diameter: Boron Oxide: 10 2.0 μm Comparative 0.5-1.5 μm Sodium Silicate: 10 Secondary: Cu Example: 30 g/L Water: Remainder 40 μm 0.5-0.1

TABLE-US-00009 TABLE 9 Primary Metal Joining Anchor Components of Fusing Agent Layer and Adhesion Base Forming and Concentration (g/L) of Sintering Condition Secondary Metal Strength Material Material Each Component Temperature × Time Layer kg/cm Ceramic TiB.sub.2 Particle Kaolin: 100 1000° C. × 3 hours Primary: Ni—B 2.6-2.3 Diameter: Manganese Sulfate: 50 2.0 μm Comparative 0.5-1.5 μm Yttrium Sulfate: 5 Secondary: Cu Example: 15 g/L Zinc Sulfate: 50 40 μm 1.0-0.01 Water: Remainder

TABLE-US-00010 TABLE 10 Primary Metal Joining Anchor Components of Fusing Agent Layer and Adhesion Base Forming and Concentration (g/L) Sintering Condition Secondary Metal Strength Material Material of Each Component Temperature × Time Layer kg/cm AlN ZrC Particle Boric Acid: 30 1200° C. × 3 hours Primary: Ni—Co—B 2.4-2.1 (SHAPAL) Diameter: Manganese Sulfate: 30 2.0 μm Comparative 0.5-2.5 μm Yttrium Nitrate: 30 Secondary: Cu Example: 30 g/L Water: Remainder 10 μm 0.4-0.1

TABLE-US-00011 TABLE 11 Primary Metal Joining Anchor Components of Fusing Agent Layer and Adhesion Base Forming and Concentration (g/L) Sintering Condition Secondary Metal Strength Material Material of Each Component Temperature × Time Layer kg/cm GaAs SiO.sub.2 Particle Molybdenum Oxide: 10 1000° C. × 4 hours Primary: Ni—B—W 2.9-2.7 Diameter: Boron Oxide: 50 2.0 μm Comparative 0.5-1.5 μm Vanadium Sulfate: 50 Secondary: Cu Example: 40 g/L Water: Remainder 40 μm 0.1-0.01

TABLE-US-00012 TABLE 12 Primary Metal Joining Anchor Components of Fusing Agent Layer and Adhesion Base Forming and Concentration (g/L.Math.) Sintering Condition Secondary Metal Strength Material Material of Each Component Temperature × Time Layer kg/cm GaN CeO.sub.2 Particle Ammonium Tungstate: 10 1200° C. × 3 hours Primary: Co—B 2.4-2.2 Diameter: Tantalum Sulfate: 10 1.0 μm Comparative 0.5-1.5 μm Yttrium Nitrate: 50 Secondary: Cu Example: 30 g/L Silver Nitrate: 3 40 μm 0.3-0.1 Water: Remainder

TABLE-US-00013 TABLE 13 Primary Metal Joining Anchor Components of Fusing Agent Layer and Adhesion Base Forming and Concentration (g/L) Sintering Condition Secondary Metal Strength Material Material of Each Component Temperature × Time Layer kg/cm GaO SiC Particle Sodium Silicate: 20 1000° C. × 4 hours Primary: Co—P 2.0-2.0 Diameter: Tin Sulfate: 10 1.0 μm Comparative 0.5-1.0 μm Calcium Hydroxide: 20 Secondary: Cu Example: 50 g/L Titanium Sulfate: 50 40 μm 0.1-0.05 Water: Remainder

TABLE-US-00014 TABLE 14 Primary Metal Joining Anchor Components of Fusing Agent Layer and Adhesion Base Forming and Concentration (g/L) Sintering Condition Secondary Metal Strength Material Material of Each Component Temperature × Time Layer kg/cm Si Wafer Silica Gel Sodium Silicate: 10 900° C. × 2 hours Primary: Ni—B 2.0-2.0 Particle Zinc Sulfate: 10 2.0 μm Comparative Diameter: Titanium Sulfate: 5 Secondary: Ni Example: 0.5-1.0 μm Bismuth Citrate: 10 5 μm 0.1-0.01 20 g/L Water: Remainder

TABLE-US-00015 TABLE 15 Primary Metal Joining Anchor Components of Fusing Agent Layer and Adhesion Base Forming and Concentration (g/L) Sintering Condition Secondary Metal Strength Material Material of Each Component Temperature × Time Layer kg/cm SiC SiC Particle Boric Acid: 100 1400° C. × 3 hours Primary: Cu 2.6-2.4 Diameter: Glaze (SK-12): 20 2.0 μm Comparative 0.5-1.6 μm Titanium Nitrate: 50 Secondary: Cu Example: 10 g/L Bismuth Citrate: 10 40 μm 0.6-0.1 Al.sub.2O.sub.3 Silver Nitrate: 20 1.0-5.0 μm Water: Remainder 50 g/L

TABLE-US-00016 TABLE 16 Primary Metal Joining Anchor Components of Fusing Agent Layer and Adhesion Base Forming and Concentration (g/L) Sintering Condition Secondary Metal Strength Material Material of Each Component Temperature × Time Layer kg/cm AlN BN: 1.0-5.0 μm Sodium Silicate: 20 1200° C. × 3 hours Primary: Ni—P 2.1-2.0 15 g/L Kaolin: 10 1.0 μm Comparative WC: 1.0-5.0 μm Silane Coupling Agent A-1100: 5 Secondary: Cu Example: 10 g/L Titanium Chloride: 2 30 μm 0.1-0.01 SiO.sub.2 Fibers: Copper Nitrate: 20 10 g/L Silver Nitrate: 20 Water: Remainder

TABLE-US-00017 TABLE 17 Primary Metal Joining Anchor Components of Fusing Agent Layer and Adhesion Base Forming and Concentration (g/L) Sintering Condition Secondary Metal Strength Material Material of Each Component Temperature × Time Layer kg/cm GaN B.sub.4C: 1.0-5.0 μm Yttrium Oxide: 50 1000° C. × 2 hours Primary: Cu 2.4-2.2 10 g/L GeSO.sub.4: 10 2.0 μm Comparative Si.sub.3N.sub.4: 0.5-5.0 μm B.sub.2O.sub.3: 50 Secondary: Example: 10 g/L V.sub.2O.sub.5: 50 Cu—Ni—Au 0.2-0.05 WSiC: 1.0-5.0 μm Sodium Silicate: 10 30 μm 10 g/L Water: Remainder

TABLE-US-00018 TABLE 18 Primary Metal Joining Anchor Components of Fusing Agent Layer and Adhesion Base Forming and Concentration (g/L) Sintering Condition Secondary Metal Strength Material Material of Each Component Temperature × Time Layer kg/cm Al.sub.2O.sub.3 SiO.sub.2: 1.0-5.0 μm Ammonium Tungstate: 100 1200° C. × 3 hours Primary: 2.0-2.0 10 g/L Vanadium Sulfate: 20 Sputtering Ti/Cu Comparative Al.sub.2O.sub.3: 1.0-5.0 μm Boric Acid: 50 1 μm Example: 20 g/L Water: Remainder Secondary: Cu 0.1-0.01 30 μm

TABLE-US-00019 TABLE 19 Primary Metal Joining Anchor Components of Fusing Agent Layer and Adhesion Base Forming and Concentration (g/L) Sintering Condition Secondary Metal Strength Material Material of Each Component Temperature × Time Layer kg/cm AlN SiC: 1.0-5.0 μm Ammonium Molybdate: 50 1000° C. × 4 hours Primary: 2.0-2.0 10 g/L Boric Acid: 10 Sputtering Cr/Cu Comparative BN: 0.5-5.0 μm Silver Nitrate: 20 1 μm Example: 10 g/L Water: Remainder Secondary: Cu 0.3-0.05 30 μm

TABLE-US-00020 TABLE 20 Primary Metal Joining Anchor Components of Fusing Agent Layer and Adhesion Base Forming and Concentration (g/L) Sintering Condition Secondary Metal Strength Material Material of Each Component Temperature × Time Layer kg/cm Pyrex SiO.sub.2: 1.0-5.0 μm Copper Sulfate: 20 1000° C. × 3 hours Primary: CVD 2.1-2.0 Glass 30 g/L Titanium Sulfate: 30 Ti/Cr/Cu Comparative Silver Nitrate: 30 1 μm Example: Water Glass: 20 Secondary: Cu 0.1-0.01 Water: Remainder 30 μm

TABLE-US-00021 TABLE 21 Primary Metal Joining Anchor Components of Fusing Agent Layer and Adhesion Base Forming and Concentration (g/L) Sintering Condition Secondary Metal Strength Material Material of Each Component Temperature × Time Layer kg/cm Sapphire TiB: 1.0-5.0 μm Germanium Sulfate: 20 1000° C. × 3 hours Primary: Cu 2.6-2.5 10 g/L Sodium Silicate: 50 2.0 μm Comparative Artificial Diamond: Al(OH).sub.3: 10 Secondary: Cu Example: 1.0-5.0 μm Manganese Sulfate: 10 40 μm 0.3-0.05 50 g/L Silane Coupling Agent (A-1100): 5 Water: Remainder

[0207] As described above, Examples 10 to 29 listed in Tables 2 to 21 exhibited an adhesion strength of 2.9 to 2.0 kg/cm.

[0208] In contrast, the peel strength in the case of not applying the fusing agent (Comparative Examples) was 1.0 to 0.01 kg/cm.

[0209] Compared with Comparative Examples, the present examples exhibited remarkably higher strength, and furthermore exhibited a very small variation in the data.

[0210] A substrate for power semiconductors needs a peel strength of 1.0 kg/cm or higher. In Comparative Examples, a portion having the maximum strength of 1 kg was present in a test piece, meanwhile other portions in the same test piece had a low strength and thus, all of the other portions did not satisfy the condition.

[0211] It was revealed that, according to the present invention, the strength was twice or higher the required minimum strength, and not only the strength was high, but also variation in the strength was small, and furthermore, even when components of a fusing agent were changed, the strength was stably achieved, and thus, it was found that joining with higher reliability was achieved.

INDUSTRIAL APPLICABILITY

[0212] The present invention is mainly used for heat sinks for power transistors and LED, components of electric vehicles, fuel cells, and the likes, and the achievement of substantial growth can be expected.

REFERENCE SIGNS LIST

[0213] 1 joining base material

[0214] 2 intermediate layer coating

[0215] 3 anchor forming material

[0216] 4 primary metal layer

[0217] 5 secondary metal layer