Abstract: Provided are a solar cell substrate made of stainless steel foil which contains 7% to 40% by mass Cr and has a coefficient of linear expansion of 12.0×10?6/° C. or less at 0° C. to 100° C. and a thickness of 20 ?m to 200 ?m is subjected to the preparatory heat treatment for stress relief in an atmosphere consisting of one or more selected from an N2 gas, an H2 gas, an Ar gas, an AX gas, and an HN gas within the range of 250° C. to 1,050° C.; a back-contact made of a Mo layer is formed on a surface of the stainless steel foil subjected to the preparatory heat treatment or an insulating coating is formed on a surface of the stainless steel foil followed by forming the back-contact including the Mo layer thereon; and an absorber layer made of Cu(In1-xGax)Se2 is formed on the back-contact by performing coating formation heat treatment.

Abstract: Provided are a solar cell substrate made of stainless steel foil which contains 7% to 40% by mass Cr and has a coefficient of linear expansion of 12.0×10?6/° C. or less at 0° C. to 100° C. and a thickness of 20 ?m to 200 ?m is subjected to the preparatory heat treatment for stress relief in an atmosphere consisting of one or more selected from an N2 gas, an H2 gas, an Ar gas, an AX gas, and an HN gas within the range of 250° C. to 1,050° C.; a back-contact made of a Mo layer is formed on a surface of the stainless steel foil subjected to the preparatory heat treatment or an insulating coating is formed on a surface of the stainless steel foil followed by forming the back-contact including the Mo layer thereon; and an absorber layer made of Cu(In1-xGax)Se2 is formed on the back-contact by performing coating formation heat treatment.