Low-temperature growth of single-crystal Cu(In,Ga)Se2 films by pulsed electron deposition technique

High quality epitaxial crystalline Cu(In,Ga)Se 2 (CIGS)films were grown on n-type (1 0 0)—Germanium (Ge) substrates using pulsed electron deposition (PED) technique at a remarkably low substrate temperature of 3001C, thanks to the high-energy of adatoms arriving to the substrate. The crystalline quality was confirmed by X-ray diffraction techniques and from Transmission Electron Microscopy and the only defects found were twin boundaries along the (1 1 2) direction in these CIGSfilms; surprisingly neither misfit dislocations nor Kinkerdall voids were observed. A 100 meV optical band located below the band edge was observed by Photoluminescence technique. Current‐voltage and capacitance‐voltage measurements confirm an intrinsic p-type conductivity of CIGSfilms, with a free carrier concentration of E3.5!10 16 cm "3