Ag incorporation in low-temperature grown Cu(In,Ga)Se2 solar cells using Ag precursor layers

Abstract

In this work, with Ag alloying, we attempted to improve the microstructure and device performance of low-temperature grown Cu(In,Ga)Se2 (CIGS) solar cells. Ag precursors with various thicknesses are deposited onto Mo prior to the CIGS growth step, and absorber films are formed via a single-step co-evaporation at a substrate temperature of 350°C. The addition of Ag in low-temperature grown CIGS films induces significant recrystallization and Na incorporation. Through adjustment of the Ag content of the Ag-alloyed CIGS films, an improved device performance is obtained compared with a CIGS solar cell without Ag alloying.