Investigating sputtered Cu2Si1−xSnxS3 [CSTS] for earth abundant thin film photovoltaics

This study investigates the synthesis of chalcopyrite Cu
2
Si
1−x
Sn
x
S
3
(CSTS) thin films for photovoltaic solar cell absorber layers. Preliminary results indicate that layered sputtering of Cu, Sn, and Si followed by annealing in a sulfur atmosphere at 500°C does not provide adequate mixing or sulfur incorporation. Annealing/sulfurizing a homogeneous co-sputtered film of Cu, Sn, and S lead to CSTS formation, although low sulfur incorporation and undesired copper sulfide phase formation resolved. Sputtering from sulfide targets may lead to formation of CSTS.