Sputtering target and method for producing same

Patent metadata

Field	Value
Publication number	US-9607812-B2
Application number	US-201314380610-A
Country	US
Kind code	B2
Filing date	Feb 15, 2013
Priority date	Feb 24, 2012
Publication date	Mar 28, 2017
Grant date	Mar 28, 2017

Abstract

Provided is a sputtering target which contains Na in high concentration and, despite this, is inhibited from discoloration, generating spots, and causing abnormal electrical discharge and which has high strength and rarely breaks. Also provided is a method for producing the sputtering target. The sputtering target has a component composition that contains 10 to 40 at % of Ga and 1.0 to 15 at % of Na as metal element components other than F, S, and Se, with the remainder composed of Cu and unavoidable impurities, wherein the Na is contained in the form of at least one Na compound selected from sodium fluoride, sodium sulfide, and sodium selenide. The sputtering target has a theoretical density ratio of 90% or higher, a flexural strength of 100 N/mm 2 or higher, and a bulk resistivity of 1 mΩ·cm or less. The number of 0.05 mm 2 or larger aggregates of the at least one of sodium fluoride, sodium sulfide, and sodium selenide present per cm 2 area of the target surface is 1 or less on average.

First claim

What is claimed is:

1. A sputtering target having a component composition that contains 10 to 40 at % of Ga and 1.0 to 15 at % of Na as metal element components other than F, S, and Se, with the remainder composed of Cu and unavoidable impurities,
wherein
the Na is contained in the form of at least one Na compound selected from sodium fluoride, sodium sulfide, and sodium selenide,
the sputtering target has a theoretical density ratio of 90% or higher,
a flexural strength of 100 N/mm 2 or higher,
a bulk resistivity of 1 mΩ·cm or less,
a content of oxygen of 200 to 2000 ppm, and
the number of 0.05 mm 2 or larger aggregates of the Na compound present per cm 2 area of the target surface is 1 or less on average.

2. The sputtering target according to claim 1 , wherein the sputtering target has a structure in which a Na compound phase is dispersed in a target material and the average particle diameter of the Na compound phase is 10 μm or less.

3. The sputtering target according to claim 1 , wherein the average particle diameter of a metal phase in the target material is 20 μm or less.

4. A method for producing the sputtering target according to claim 1 , the method comprising:
a step of drying an Na compound powder at a temperature of 70° C. or higher prior to preparing a powder mixture of Na compound powder into the powder and Cu—Ga powder,
a step of sintering the powder mixture,
wherein
the Cu—Ga powder is composed of Cu—Ga alloy powder or Cu—Ga alloy powder and Cu powder,
the average particle diameter of the Cu—Ga powder is 1 to 45 μm, and
the proportion of the Cu—Ga powder particles having a particle diameter of 30 μm or less is over half of the total powder weight of the Cu—Ga powder.

5. The method for producing a sputtering target according to claim 1 , the method comprising:
a step of sintering a powder mixture of Na compound powder and Cu—Ga powder,
a step of drying the powder mixture at a temperature of 70° C. or higher,
wherein the Cu—Ga powder is composed of Cu—Ga alloy powder or Cu—Ga alloy powder and Cu powder, the average particle diameter of the Cu—Ga powder is 1 to 45 μm, and the proportion of the Cu—Ga powder particles having a particle diameter of 30 μm or less is over half of the total powder weight of the Cu—Ga powder.

6. The method for producing a sputtering target according to claim 4 , the method comprising: sintering the powder mixture in a non-oxidizing atmosphere or in a vacuum in the step of sintering the powder mixture.

Assignees

• Mitsubishi Materials Corp

Inventors

• Zhang Shoubin
• Umemoto Keita
• Shoji Masahiro

Classifications

• B22F2201/20

  Use of vacuum · CPC title

• C23C14/0623

  Sulfides, selenides or tellurides · CPC title

• C23C14/3414

  Metallurgical or chemical aspects of target preparation, e.g. casting, powder metallurgy · CPC title

• H01J37/3429 Primary

  Plural materials · CPC title

• B22F3/10

  Sintering only · CPC title