Single-crystal CuIn1−xGaxSe2 films grown on lattice-matched Ge by low-temperature Pulsed Electron Deposition technique

We report on the epitaxial growth of Cu(In,Ga)Se
₂
(CIGS) thin films on n-type Ge substrates using the Pulsed Electron Deposition (PED) technique. Single-crystal films with smooth interface and no dislocations were obtained at a substrate temperature of 300°C with thickness above 1.5μm. CIGS/Ge epilayers were characterized in terms of Transmission Electron Microscopy, X-Ray Diffraction and Photoluminescence. Preliminary results are very promising for a variety of potential applications as absorber layer in single and multi-junction thin-film solar cells.