Cu—Ga target, method of producing same, light-absorbing layer formed from Cu—Ga based alloy film, and CIGS system solar cell having the light-absorbing layer

Patent metadata

Field	Value
Publication number	US-10050160-B2
Application number	US-201113988363-A
Country	US
Kind code	B2
Filing date	Aug 10, 2011
Priority date	Jan 17, 2011
Publication date	Aug 14, 2018
Grant date	Aug 14, 2018

Abstract

A Cu—Ga alloy sintered-compact sputtering target having a Ga concentration of 40 to 50 at % and Cu as the balance, wherein the sintered-compact sputtering target is characterized in that the relative density is 80% or higher, and the compositional deviation of the Ga concentration is within ±0.5 at % of the intended composition. A method of producing a Cu—Ga alloy sintered-compact sputtering target having a Ga concentration of 40 to 50 at % and Cu as the balance, wherein the method thereof is characterized in that Cu and Ga raw materials are melted and cooled/pulverized to produce a Cu—Ga alloy raw material powder, and the obtained material powder is further hot-pressed with a retention temperature being between the melting point of the mixed raw material powder and a temperature 15° C. lower than the melting point and with a pressure of 400 kgf/cm 2 or more applied to the sintered mixed raw material powder. Provided are a sputtering target having very low compositional deviation and high density; a method of producing the target; a light-absorbing layer having a Cu—Ga based alloy film; and a CIGS solar cell including the light-absorbing layer.

First claim

The invention claimed is:

1. A Cu—Ga alloy sintered compact sputtering target having a structure consisting of a single composition alloy having a Ga concentration of 40 to 50 at % and Cu as the balance, wherein the relative density is 80% or higher, and no Ga phase is present.

2. A method of producing a Cu—Ga based alloy sintered compact sputtering target having a structure consisting of a single composition alloy having a Ga concentration of 40 to 50 at % and Cu as the balance, a relative density of 80% or higher, and no Ga phase present within the sputtering target, comprising the steps of:
producing a Cu—Ga alloy raw material powder by melting, cooling and pulverizing Cu and Ga raw materials; and
hot-pressing the raw material powder at a retention temperature being between the melting point of the mixed raw material powder and a temperature 15° C. lower than the melting point and with a pressure of 400 kgf/cm 2 or more applied to the sintering mixed raw material powder.

3. A light-absorbing layer comprising a Cu—Ga based alloy film formed on a substrate using the Cu—Ga alloy sintered compact sputtering target according to claim 1 .

4. A CIGS system solar cell comprising the light-absorbing layer according to claim 3 .

5. The method according to claim 2 , wherein compositional deviation of the Ga concentration is within ±0.5 at % of the intended composition.

Assignees

• Tamura Tomoya
• Yamamoto Hiroyoshi
• Sakamoto Masaru
• Jx Nippon Mining & Metals Corp

Inventors

• Tamura Tomoya
• Yamamoto Hiroyoshi
• Sakamoto Masaru

Classifications

• C22C9/00

  Alloys based on copper · CPC title

• Y02E10/541

  CuInSe2 material PV cells · CPC title

• C22C28/00

  Alloys based on a metal not provided for in groups C22C5/00 - C22C27/00 · CPC title

• B22F9/04

  starting from solid material, e.g. by crushing, grinding or milling ({C22C1/1084 takes precedence}; crushing, grinding or milling, in general, see the relevant subclasses, e.g. B02C) · CPC title

• C23C14/3414

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