Cu-Ga alloy sputtering target and method for manufacturing same

Abstract

This Cu-Ga alloy sputtering target has a component composition containing 0.1-40.0% (atom basis) of Ga with the remainder made up by Cu and unavoidable impurities, wherein the porosity of the target is 3.0% or less, the average diameter of inscribed circles of the pores is 150 [mu]m or less, and the average crystal grain diameter of Cu-Ga alloy grains is 50 [mu]m or less.

Description

technical field [0001] The present invention relates to a Cu-Ga alloy sputtering target used for forming a Cu-In-Ga-Se compound film (hereinafter, sometimes abbreviated as CIGS film) used as a light absorbing layer of a thin-film solar cell and its production method. [0002] This application claims priority based on Patent Application No. 2014-140261 filed in Japan on July 8, 2014 and Patent Application No. 2015-123998 filed in Japan on June 19, 2015, and uses the contents thereof here. Background technique [0003] Various developments are being made on Cu-In-Ga-Se quaternary alloy films. A Cu-Ga alloy sputtering target is an essential material for manufacturing a solar cell using a Cu-In-Ga-Se quaternary alloy film (CIGS film) produced by a selenium (Se) method as a light absorbing layer. In addition, the so-called selenization method is, for example, H at 500°C 2 A method in which CuGa is sputtered to about 500 nm and then In is sputtered to about 500 nm is heated in ...

AI Technical Summary

Problems solved by technology

For the voids, for example, when the porosity is only limited to 1.0% or less, if there are only tiny voids, even high-power sputtering can reduce the frequent occurrence of abnormal discharges, but if there are large voids, then It is easy to generate splash and abnormal discharge starting from the periphery of the hole

Therefore, in a sputtering target whose porosity is only controlled below 1.0%, high-power sputtering cannot be performed stably, especially when a large-area sputtering target is used.

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