Design and testing of pilot-scale Cu and mixed-vapor Ga-In evaporation sources

There are a number of requirements in the design of evaporation sources for the inline deposition of Cu(InGa)Se₂ absorber layers. These include evaporation rates ≫10g/hr without anomalous behavior such as spitting, spatial composition uniformity across the area of thousands or tens of thousands of consecutive substrates, and low capital and maintenance costs. To meet these requirements, both quantitative and qualitative design considerations must be made, including thermal and flow modeling, fabrication methods, and material properties such as thermal and chemical compatibilities.