Oxide sintered body, sputtering target, and oxide semiconductor thin film obtained using sputtering target

Patent metadata

Field	Value
Publication number	US-10128108-B2
Application number	US-201515520983-A
Country	US
Kind code	B2
Filing date	Nov 16, 2015
Priority date	Nov 25, 2014
Publication date	Nov 13, 2018
Grant date	Nov 13, 2018

Abstract

Provided are an oxide sintered compact whereby low carrier density and high carrier mobility are obtained when the oxide sintered compact is used to obtain an oxide semiconductor thin film by a sputtering method, and a sputtering target which uses the oxide sintered compact. This oxide sintered compact contains oxides of indium, gallium, and aluminum. The gallium content is from 0.15 to 0.49 by Ga/(In+Ga) atomic ratio, and the aluminum content is from 0.0001 to less than 0.25 by Al/(In+Ga+Al) atomic ratio. A crystalline oxide semiconductor thin film formed using this oxide sintered compact as a sputtering target is obtained at a carrier density of 4.0×1018 cm−3 or less and a carrier mobility of 10 cm−2V−1sec−1 or greater.

First claim

The invention claimed is:

1. An oxide sintered body comprising indium, gallium, and aluminum as oxides, wherein
the content of the gallium is 0.15 or more and 0.49 or less in terms of Ga/(In+Ga) atomic ratio, and
the content of the aluminum is 0.0001 or more and less than 0.25 in terms of Al/(In+Ga+Al) atomic ratio,
the oxide sintered body includes an In 2 O 3 phase having a bixbyite-type structure, and a GaInO 3 phase having a β-Ga 2 O 3 -type structure as a formed phase other than the In 2 O 3 phase, or a GaInO 3 phase having a β-Ga 2 O 3 -type structure and a (Ga, In) 2 O 3 phase as a formed phase other than the In 2 O 3 phase.

2. The oxide sintered body according to claim 1 , wherein the content of the aluminum is 0.01 or more and 0.20 or less in terms of Al/(In+Ga+Al) atomic ratio.

3. The oxide sintered body according to claim 1 , wherein the content of the gallium is 0.20 or more and 0.45 or less in terms of Ga/(In+Ga) atomic ratio.

4. A sputtering target obtained by machining the oxide sintered body according to claim 1 .

Assignees

• Sumitomo Metal Mining Co

Inventors

• Nishimura Eiichiro
• Nakayama Tokuyuki
• Matsumura Fumihiko

Classifications

• H10P95/70

  Chemical treatments · CPC title

• H10P52/00

  Grinding, lapping or polishing of wafers, substrates or parts of devices · CPC title

• H10P50/20

  Dry etching; Plasma etching; Reactive-ion etching · CPC title

• H10P14/3454

  Amorphous · CPC title

• H10P14/2922

  being non-crystalline insulating materials, e.g. glass or polymers · CPC title