Pulsed laser deposition of InP thin films on sapphire(1 0 0 0) and GaAs(1 0 0)

Indium phosphide thin films were deposited on sapphire and GaAs(1 0 0) substrates by pulsed laser deposition using a XeCl excimer laser in argon background gas and in high vacuum. The grown film structure and morphology were observed by reflection high-energy electron diffraction, scanning electron microscopy, and atomic force microscopy. The films were grown on sapphire were found to be disordered with the argon gas background enhancing the particulate formation. Epitaxial InP(1 0 0) film with oriented polyhedral islands were grown on hydrogen-cleaned GaAs(1 0 0) at a substrate temperature of 573 K at 1 10 8 Torr background pressure. By varying the deposition parameters, relatively smooth InP films with average surface roughness of about 4–12 nm were obtained.