Synthesis of the single phase CIGS particle by solvothermal method for solar cell application

Uniform CIGS powder synthesis is required more these days to produce CIGS solar cell using thick film process. Solvothermal CIGS powder synthesis method, among other synthesis methods, is mainly used because it is simple and easy for mass production. But all CIGS synthesis result reported up to now are mixed with CIS, CIGS and CGS, and there was no result that reported single phase CIGS synthesis. Especially, comparable single phase CIGS was synthesized in the CIGS powder synthesis using metal source, but small amount of CIS powder were still remained. In this study, we examined the CIGS synthesis paths in solvothermal method, and synthesize single phase CIGS. CGS seed was synthesized using Cu, In, GaCl₃, Se sources by keeping 12 h at 180 °C, and we were able to synthesize single phase CIGS by keeping it for 24 h at raised temperature of 230 °C. The synthesized CIGS formed uniform particles with its size of less than 100 nm, and was shown in strong agglomeration.