Sintered compact magnesium oxide target for sputtering, and method for producing same

Abstract

A sintered compact magnesium oxide target for sputtering having a purity of 99.99 wt % or higher excluding C, a density of 3.57 g/cm.sup.3 or higher, and a whiteness of 60% or less. In order to uniformly deposit a magnesium oxide film, a magnesium oxide target having a higher purity and a higher density is being demanded. An object of this invention is to provide a target capable of realizing the above, and a method for producing such a target. While a magnesium oxide sintered compact sputtering target is produced by hot-pressing a raw material powder, there is a problem in that color shading occurs in roughly 60 (within a circle having a diameter of 60 mm) at the center part of the target. Conventionally, no particularly attention was given to this problem. However, in recent years, it has become necessary to investigate and resolve this problem in order to improve the deposition quality.

Claims

1. A sputtering target comprising a sintered compact of magnesium oxide having a purity of 99.99 wt % or higher excluding C, a density of 3.57 g/cm.sup.3 or higher, and a whiteness of 60% or less.

2. The sputtering target according to claim 1, wherein the sintered compact of magnesium oxide is produced by sintering a raw material powder obtained by mixing a magnesium oxide (MgO) powder with a magnesium carbonate (MgCO.sub.3) powder of an amount of 5 wt % or more and less than 30 wt %.

3. The sputtering target according to claim 2, wherein the whiteness is 55% or higher and 60% or less.

4. The sputtering target according to claim 3, wherein the whiteness has a variation within 5%.

5. The sputtering target according to claim 1, wherein the whiteness is 55% or higher and 60% or less.

6. The sputtering target according to claim 1, wherein in the whiteness has a variation within 5%.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a diagram showing the correlation of the additive amount of magnesium carbonate (MgCO.sub.3) and the relative density of the sintered compact magnesium oxide target.

(2) FIG. 2 is a diagram showing the correlation of the additive amount of magnesium carbonate (MgCO.sub.3) and the whiteness of the sintered compact magnesium oxide target.

DETAILED DESCRIPTION

(3) The sintered compact magnesium oxide target for sputtering of the present invention has a purity of 99.99 wt % or higher excluding C, a density of 3.57 g/cm.sup.3 or higher, and a whiteness of 60% or less, and a major feature of the present invention is that the sintered compact magnesium oxide target for sputtering has a whiteness of 55% or higher and 60% or less.

(4) This target can be realized by producing the target using a raw material obtained by adding MgCO.sub.3 in an amount of 5 wt % or more and less than 30 wt % to magnesium oxide (MgO). Note that the whiteness was measured using the micro surface spectral color difference meter VSS400 (JIS Z 8722, ASTM E 308) manufactured by Nippon Denshoku Industries. This Hunter-type color difference meter was used to measure L: luminosity and a.Math.b (hue.Math.chroma), and the whiteness was obtained from the following formula.
W (whiteness)=100[(100L).sup.2+(a.sup.2+b.sup.2)].sup.1/2 Formula

(5) Conventionally, magnesium oxide (MgO) was sintered, but sufficient density could not be obtained unless the sintering temperature was set high. The present invention can achieve a density of 3.57 g/cm.sup.3 or more with a sintering temperature of 1500 C. or less as described below. This is a low temperature compared to conventional methods, and thus it is possible to reduce the production cost. In addition, the present invention can obtain a sintered compact magnesium oxide target for sputtering having a purity of 99.99% or higher excluding C.

(6) As described above, it is even more advantageous to have an effect of reducing the nodules and particles because reduction of the variation in whiteness causes improvement in the uniformity of the sintered compact. Here, the variation in whiteness is preferably adjusted to be within 5%.

(7) Upon producing the sintered compact magnesium oxide target for sputtering of the present invention, a MgCO.sub.3 raw material in an amount of 5 wt % or more and less than 30 wt % is used. This raw material has a purity of 99.99 wt % or higher excluding C, and, after mixing the MgCO.sub.3 raw material powders having an average grain size of 0.5 m or less, the mixed powders are hot pressed at a temperature of 1500 C. or less and an applied pressure of 300 kgf/cm.sup.2 or more to obtain a target having a purity of 99.99 wt % or higher excluding C, and a density of 3.57 g/cm.sup.3 or higher. Note that magnesium carbonate (MgCO.sub.3) is decomposed during sintering (MgCO.sub.3.fwdarw.MgO+CO.sub.2).

EXAMPLES

(8) The Examples are now explained. Note that these Examples merely illustrate preferred representative examples, and it should be easy to understand that the present invention should not be limited to these Examples. The technical concept of the present invention shall be interpreted based on the overall descriptions of this specification and particularly based on the scope of claims.

Example 1

(9) The sintered compact magnesium oxide target for sputtering was produced according to the following method. A raw material powder containing MgCO.sub.3 in an amount of 6.0 wt % and remainder being magnesium oxide (MgO) having a purity of 99.99 wt % or higher excluding C and an average grain size of 0.5 m or less was mixed. Note that the C content in this raw material powder was 0.86 wt %.

(10) Subsequently, this mixed powder was hot pressed for 2 hours at a temperature of 1500 C. and an applied pressure of 300 kgf/cm.sup.2 to produce a magnesium oxide target having a purity of 99.99 wt % or higher excluding C. Note that, since magnesium carbonate (MgCO.sub.3) is decomposed during sintering (MgCO.sub.3.fwdarw.MgO+CO.sub.2), magnesium carbonate (MgCO.sub.3) does not exist in the sintered target. The density of the obtained MgO sintered compact was measured with the Archimedes method. Consequently, a density of 3.576 g/cm.sup.3 (relative density 99.74%) was obtained.

(11) The sintered compact produced as described above was subject to grinding and polishing to obtain a sintered compact magnesium oxide target for sputtering. Upon visually observing the target, the color was gray, and the target possessed optical transparency. Moreover, upon examining the whiteness of the target, the whiteness was 58.6%. In addition, the variation in whiteness was 3.9%. For this whiteness, the whiteness by Hunter (Lab) was obtained by using the micro surface spectral color difference meter VSS400 manufactured by Nippon Denshoku Industries. The measuring range diameter in the foregoing case was 0.2 mm. Three points were randomly measured to obtain the average value and variation () thereof. In the following Examples and Comparative Examples, the whiteness was measured and the variation thereof was measured in a similar manner.

(12) TABLE-US-00001 TABLE 1 Additive Amount of MgCO.sub.3 Sintered Variation C Content Raw Sintering Hold Pressing Compact Relative in in Raw Material Temperature Time Pressure Density Density Optical Whiteness Whiteness Material (wt. %) ( C.) (Hours) (kgf/cm.sup.2) (g/cm.sup.3) (%) Color Transparency (%) (%) (wt. %) Comparative 0.0 1500 2 300 3.280 91.49 White No 91.3 1.4 0.00 Example 1 Comparative 1.8 1500 2 300 3.482 97.11 White No 81.5 1.6 0.26 Example 2 Comparative 3.0 1500 2 300 3.540 98.74 Light gray, Yes 72.2 10.5 0.43 Example 3 spots Comparative 4.2 1500 2 300 3.568 99.53 Light gray Yes 63.5 0.3 0.60 Example 4 Example 1 6.0 1500 2 300 3.576 99.74 Gray Yes 58.6 3.9 0.86 Example 2 9.0 1500 2 300 3.576 99.75 Gray Yes 57.6 0.6 1.28 Example 3 12.0 1500 2 300 3.572 99.64 Gray Yes 55.6 3.2 1.71 Example 4 15.0 1500 2 300 3.577 99.79 Gray Yes 56.6 1.1 2.14 Example 5 18.0 1500 2 300 3.571 99.62 Gray Yes 56.1 3.4 2.57 Comparative 30.0 1500 2 300 3.572 99.62 Gray, spots Yes 56.5 5.2 4.28 Example 5 Comparative 48.0 1500 2 300 3.577 99.78 Gray, spots Yes 56.4 6.8 6.84 Example 6 Comparative 60.0 1500 2 300 3.573 99.65 Gray, spots, Yes 56.6 8.1 8.55 Example 7 cracks

Example 2

(13) The sintered compact magnesium oxide target for sputtering was produced according to the following method. A raw material powder containing MgCO.sub.3 in an amount of 9.0 wt % and remainder being magnesium oxide (MgO) having a purity of 99.99 wt % or higher excluding C and an average grain size of 0.5 m or less was mixed. Note that the C content in this raw material powder was 1.28 wt %.

(14) Subsequently, this mixed powder was hot pressed for 2 hours at a temperature of 1500 C. and an applied pressure of 300 kgf/cm.sup.2 to produce a magnesium oxide target having a purity of 99.99 wt % or higher excluding C. Note that, since magnesium carbonate (MgCO.sub.3) is decomposed during sintering (MgCO.sub.3.fwdarw.MgO+CO.sub.2), magnesium carbonate (MgCO.sub.3) does not exist in the sintered target. The density of the obtained MgO sintered compact was measured with the Archimedes method. Consequently, a density of 3.576 g/cm.sup.3 (relative density 99.75%) was obtained.

(15) The sintered compact produced as described above was subject to grinding and polishing to obtain a sintered compact magnesium oxide target for sputtering. Upon visually observing the target, the color was gray, and the target possessed optical transparency. Moreover, upon examining the whiteness of the target, the whiteness was 57.6%. In addition, the variation in whiteness was 0.6%.

Example 3

(16) The sintered compact magnesium oxide target for sputtering was produced according to the following method. A raw material powder containing MgCO.sub.3 in an amount of 12.0 wt % and remainder being magnesium oxide (MgO) having a purity of 99.99 wt % or higher excluding C and an average grain size of 0.5 m or less was mixed. Note that the C content in this raw material powder was 1.71 wt %.

(17) Subsequently, this mixed powder was hot pressed for 2 hours at a temperature of 1500 C. and an applied pressure of 300 kgf/cm.sup.2 to produce a magnesium oxide target having a purity of 99.99 wt % or higher excluding C. Note that, since magnesium carbonate (MgCO.sub.3) is decomposed during sintering (MgCO.sub.3.fwdarw.MgO+CO.sub.2), magnesium carbonate (MgCO.sub.3) does not exist in the sintered target. The density of the obtained MgO sintered compact was measured with the Archimedes method. Consequently, a density of 3.572 g/cm.sup.3 (relative density 99.64%) was obtained.

(18) The sintered compact produced as described above was subject to grinding and polishing to obtain a sintered compact magnesium oxide target for sputtering. Upon visually observing the target, the color was gray, and the target possessed optical transparency. Moreover, upon examining the whiteness of the target, the whiteness was 55.6%. In addition, the variation in whiteness was 3.2%.

Example 4

(19) The sintered compact magnesium oxide target for sputtering was produced according to the following method. A raw material powder containing MgCO.sub.3 in an amount of 15.0 wt % and remainder being magnesium oxide (MgO) having a purity of 99.99 wt % or higher excluding C and an average grain size of 0.5 m or less was mixed. Note that the C content in this raw material powder was 2.14 wt %.

(20) Subsequently, this mixed powder was hot pressed for 2 hours at a temperature of 1500 C. and an applied pressure of 300 kgf/cm.sup.2 to produce a magnesium oxide target having a purity of 99.99 wt % or higher excluding C. Note that, since magnesium carbonate (MgCO.sub.3) is decomposed during sintering (MgCO.sub.3.fwdarw.MgO+CO.sub.2), magnesium carbonate (MgCO.sub.3) does not exist in the sintered target. The density of the obtained MgO sintered compact was measured with the Archimedes method. Consequently, a density of 3.577 g/cm.sup.3 (relative density 99.79%) was obtained.

(21) The sintered compact produced as described above was subject to grinding and polishing to obtain a sintered compact magnesium oxide target for sputtering. Upon visually observing the target, the color was gray, and the target possessed optical transparency. Moreover, upon examining the whiteness of the target, the whiteness was 56.6%. In addition, the variation in whiteness was 1.1%.

Example 5

(22) The sintered compact magnesium oxide target for sputtering was produced according to the following method. A raw material powder containing MgCO.sub.3 in an amount of 18.0 wt % and remainder being magnesium oxide (MgO) having a purity of 99.99 wt % or higher excluding C and an average grain size of 0.5 m or less was mixed. Note that the C content in this raw material powder was 2.57 wt %.

(23) Subsequently, this mixed powder was hot pressed for 2 hours at a temperature of 1500 C. and an applied pressure of 300 kgf/cm.sup.2 to produce a magnesium oxide target having a purity of 99.99 wt % or higher excluding C. Note that, since magnesium carbonate (MgCO.sub.3) is decomposed during sintering (MgCO.sub.3.fwdarw.MgO+CO.sub.2), magnesium carbonate (MgCO.sub.3) does not exist in the sintered target. The density of the obtained MgO sintered compact was measured with the Archimedes method. Consequently, a density of 3.571 g/cm.sup.3 (relative density 99.62%) was obtained.

(24) The sintered compact produced as described above was subject to grinding and polishing to obtain a sintered compact magnesium oxide target for sputtering. Upon visually observing the target, the color was gray, and the target possessed optical transparency. Moreover, upon examining the whiteness of the target, the whiteness was 56.1%. In addition, the variation in whiteness was 3.4%.

Comparative Example 1

(25) The sintered compact magnesium oxide target for sputtering was produced according to the following method. A raw material powder containing magnesium oxide (MgO) having a purity of 99.99 wt % or higher and an average grain size of 0.5 m or less was used. Note that magnesium carbonate (MgCO.sub.3) was not added to this raw material powder. C content was <10 ppm.

(26) Subsequently, this raw material powder was hot pressed for 2 hours at a temperature of 1500 C. and an applied pressure of 300 kgf/cm.sup.2 to produce a magnesium oxide target having a purity of 99.99 wt % or higher excluding C. The density of the obtained MgO sintered compact was measured with the Archimedes method. Consequently, a density of 3.280 g/cm.sup.3 (relative density 91.49%) was obtained. In comparison to the Examples, the density decreased significantly.

(27) The sintered compact produced as described above was subject to grinding and polishing to obtain a sintered compact magnesium oxide target for sputtering. Upon visually observing the target, the color was white, and the target did not possess optical transparency. Moreover, upon examining the whiteness of the target, the whiteness was 91.3%. In addition, the variation in whiteness was 1.4%.

Comparative Example 2

(28) The sintered compact magnesium oxide target for sputtering was produced according to the following method. A raw material powder containing magnesium oxide (MgO) and magnesium carbonate (MgCO.sub.3) in an amount of 0.18 wt % having a purity of 99.99 wt % or higher excluding C and an average grain size of 0.5 m or less was mixed. C content was 0.26 wt %. In the foregoing case, the amount of magnesium carbonate (MgCO.sub.3) did not satisfy the amount of the present invention.

(29) Subsequently, this mixed powder was hot pressed for 2 hours at a temperature of 1500 C. and an applied pressure of 300 kgf/cm.sup.2 to produce a magnesium oxide target having a purity of 99.99 wt % or higher excluding C. Note that, since magnesium carbonate (MgCO.sub.3) is decomposed during sintering (MgCO.sub.3.fwdarw.MgO+CO.sub.2), magnesium carbonate (MgCO.sub.3) does not exist in the sintered target. The density of the obtained MgO sintered compact was measured with the Archimedes method. Consequently, a density of 3.482 g/cm.sup.3 (relative density 97.11%) was obtained. In comparison to the Examples, the density decreased significantly.

(30) The sintered compact produced as described above was subject to grinding and polishing to obtain a sintered compact magnesium oxide target for sputtering. Upon visually observing the target, the color was white, and the target did not possess optical transparency. Moreover, upon examining the whiteness of the target, the whiteness was 81.5%. In addition, the variation in whiteness was 1.6%.

Comparative Example 3

(31) The sintered compact magnesium oxide target for sputtering was produced according to the following method. A raw material powder containing magnesium oxide (MgO) and magnesium carbonate (MgCO.sub.3) in an amount of 3.0 wt % having a purity of 99.99 wt % or higher excluding C and an average grain size of 0.5 m or less was mixed. C content was 0.43 wt %. In the foregoing case, the amount of magnesium carbonate (MgCO.sub.3) did not satisfy the amount of the present invention.

(32) Subsequently, this mixed powder was hot pressed for 2 hours at a temperature of 1500 C. and an applied pressure of 300 kgf/cm.sup.2 to produce a magnesium oxide target having a purity of 99.99 wt % or higher excluding C. Note that, since magnesium carbonate (MgCO.sub.3) is decomposed during sintering (MgCO.sub.3.fwdarw.MgO+CO.sub.2), magnesium carbonate (MgCO.sub.3) does not exist in the sintered target. The density of the obtained MgO sintered compact was measured with the Archimedes method. Consequently, a density of 3.540 g/cm.sup.3 (relative density 98.74%) was obtained. In comparison to the Examples, the density decreased.

(33) The sintered compact produced as described above was subject to grinding and polishing to obtain a sintered compact magnesium oxide target for sputtering. Upon visually observing the target, the color was light gray but spots appeared on the surface. The target possessed optical transparency.

(34) Moreover, upon examining the whiteness of the target, the whiteness was 72.2%. In addition, the variation in whiteness was 10.5%.

Comparative Example 4

(35) The sintered compact magnesium oxide target for sputtering was produced according to the following method. A raw material powder containing magnesium oxide (MgO) and magnesium carbonate (MgCO.sub.3) in an amount of 4.2 wt % having a purity of 99.99 wt % or higher excluding C and an average grain size of 0.5 m or less was mixed. C content was 0.60 wt %. In the foregoing case, the amount of magnesium carbonate (MgCO.sub.3) did not satisfy the amount of the present invention.

(36) Subsequently, this mixed powder was hot pressed for 2 hours at a temperature of 1500 C. and an applied pressure of 300 kgf/cm.sup.2 to produce a magnesium oxide target having a purity of 99.99 wt % or higher excluding C. Note that, since magnesium carbonate (MgCO.sub.3) is decomposed during sintering (MgCO.sub.3.fwdarw.MgO+CO.sub.2), magnesium carbonate (MgCO.sub.3) does not exist in the sintered target. The density of the obtained MgO sintered compact was measured with the Archimedes method. Consequently, a density of 3.568 g/cm.sup.3 (relative density 99.53%) was obtained. In comparison to the Examples, the density decreased.

(37) The sintered compact produced as described above was subject to grinding and polishing to obtain a sintered compact magnesium oxide target for sputtering. Upon visually observing the target, the color was light gray, and the target possessed optical transparency. Moreover, upon examining the whiteness of the target, the whiteness was 63.5%. In addition, the variation in whiteness was 0.3%.

Comparative Example 5

(38) The sintered compact magnesium oxide target for sputtering was produced according to the following method. A raw material powder containing magnesium oxide (MgO) and magnesium carbonate (MgCO.sub.3) in an amount of 30.0 wt % having a purity of 99.99 wt % or higher excluding C and an average grain size of 0.5 m or less was mixed. C content was 4.3 wt %. In the foregoing case, the amount of magnesium carbonate (MgCO.sub.3) exceeds the amount of the present invention.

(39) Subsequently, this mixed powder was hot pressed for 2 hours at a temperature of 1500 C. and an applied pressure of 300 kgf/cm.sup.2 to produce a magnesium oxide target having a purity of 99.99 wt % or higher excluding C. Note that, since magnesium carbonate (MgCO.sub.3) is decomposed during sintering (MgCO.sub.3.fwdarw.MgO+CO.sub.2), magnesium carbonate (MgCO.sub.3) does not exist in the sintered target. The density of the obtained MgO sintered compact was measured with the Archimedes method. Consequently, a density of 3.572 g/cm.sup.3 (relative density 99.62%) was obtained, and the density was equivalent to the Examples.

(40) The sintered compact produced as described above was subject to grinding and polishing to obtain a sintered compact magnesium oxide target for sputtering. Upon visually observing the target, the color was gray but spots appeared on the surface. This is considered to be a result of an increase in the amount of magnesium carbonate (MgCO.sub.3). Moreover, upon examining the whiteness of the target, the whiteness was 56.5%. In addition, the variation in whiteness was 5.2%.

Comparative Example 6

(41) The sintered compact magnesium oxide target for sputtering was produced according to the following method. A raw material powder containing magnesium oxide (MgO) and magnesium carbonate (MgCO.sub.3) in an amount of 48.0 wt % having a purity of 99.99 wt % or higher excluding C and an average grain size of 0.5 m or less was mixed. C content was 6.8 wt %. In the foregoing case, the amount of magnesium carbonate (MgCO.sub.3) exceeds the amount of the present invention.

(42) Subsequently, this mixed powder was hot pressed for 2 hours at a temperature of 1500 C. and an applied pressure of 300 kgf/cm.sup.2 to produce a magnesium oxide target having a purity of 99.99 wt % or higher excluding C. Note that, since magnesium carbonate (MgCO.sub.3) is decomposed during sintering (MgCO.sub.3.fwdarw.MgO+CO.sub.2), magnesium carbonate (MgCO.sub.3) does not exist in the sintered target. The density of the obtained MgO sintered compact was measured with the Archimedes method. Consequently, a density of 3.577 g/cm.sup.3 (relative density 99.78%) was obtained, and the density was equivalent to the Examples.

(43) The sintered compact produced as described above was subject to grinding and polishing to obtain a sintered compact magnesium oxide target for sputtering. Upon visually observing the target, the color was gray but spots appeared on the surface. This is considered to be a result of an increase in the amount of magnesium carbonate (MgCO.sub.3). Moreover, upon examining the whiteness of the target, the whiteness was 56.4%. In addition, the variation in whiteness was 6.8%.

Comparative Example 7

(44) The sintered compact magnesium oxide target for sputtering was produced according to the following method. A raw material powder containing magnesium oxide (MgO) and magnesium carbonate (MgCO.sub.3) in an amount of 60.0 wt % having a purity of 99.99 wt % or higher excluding C and an average grain size of 0.5 m or less was mixed. C content was 8.55 wt %. In the foregoing case, the amount of magnesium carbonate (MgCO.sub.3) considerably exceeds the amount of the present invention.

(45) Subsequently, this mixed powder was hot pressed for 2 hours at a temperature of 1500 C. and an applied pressure of 300 kgf/cm.sup.2 to produce a magnesium oxide target having a purity of 99.99 wt % or higher excluding C. Note that, since magnesium carbonate (MgCO.sub.3) is decomposed during sintering (MgCO.sub.3.fwdarw.MgO+CO.sub.2), magnesium carbonate (MgCO.sub.3) does not exist in the sintered target. The density of the obtained MgO sintered compact was measured with the Archimedes method. Consequently, a density of 3.573 g/cm.sup.3 (relative density 99.65%) was obtained, and the density was equivalent to the Examples.

(46) The sintered compact produced as described above was subject to grinding and polishing to obtain a sintered compact magnesium oxide target for sputtering. Upon visually observing the target, the color was gray but spots appeared on the surface. Moreover, cracks were generated in addition to the spots. This is considered to be a result of an increase in the amount of magnesium carbonate (MgCO.sub.3).

(47) Moreover, upon examining the whiteness of the target, the whiteness was 56.6%. In addition, the variation in whiteness was 8.1%.

(48) As evident from the foregoing Examples and Comparative Examples, the relative density of the sintered compact magnesium oxide target of the present invention is affected by the additive amount of the magnesium carbonate (MgCO.sub.3). A density of 3.57 g/cm.sup.3 (relative density of 99.5%) can be achieved by adding MgCO.sub.3 in an amount of 5 wt % or more and less than 30 wt %. This is shown in FIG. 1.

(49) Moreover, the whiteness of the sintered compact magnesium oxide target of the present invention is affected by the additive amount of the magnesium carbonate (MgCO.sub.3). The whiteness becomes 60% or less by adding MgCO.sub.3 in an amount of 5 wt % or more and less than 30 wt %. This is shown in FIG. 2.

(50) Accordingly, a target produced by using a raw material obtained by adding MgCO.sub.3 in an amount of 5 wt % or more and less than 30 wt % to the magnesium oxide (MgO) has a high density, and is effective as a sintered compact magnesium oxide target for sputtering.

(51) Moreover, as evident from the foregoing Examples and Comparative Examples, it is more effective to adjust the variation in whiteness to be within 5% since an effect of decreasing the cracks and nodules of the sintered compact can be obtained.

(52) The present invention yields a superior effect of being able to obtain a high purity, high density sintered compact magnesium oxide target that is free of color shading and can be produced at a low cost by selecting the appropriate raw material powder. It is also possible to improve the characteristics of the deposition of magnesium oxide. Further, the generation of particles during sputtering can be consequently inhibited. In addition, since it is possible to produce a sintered compact magnesium oxide target comprising a moderate oxygen defect, excessive oxygen is not generated during sputtering, and an effect of inhibiting oxidation of the adjacent deposition layer (metal layer) is exhibited.

(53) Accordingly, the magnesium oxide sintered compact sputtering target of the present invention is useful as a magnesium oxide sputtering target for use in forming a magnesium oxide layer for magnetic recording mediums of magnetic disk devices or tunneling magnetoresistance (TMR) elements and other electronic devices.