Growth and Characterization of InN Thin Films on Sapphire by MOCVD

Indium nitride thin films are grown on sapphire substrates by metal-organic chemical vapour deposition (MOCVD). By employing three-step layer buffers, the mirror-like layers on two-inch sapphire wafers have been obtained. The structural, optical and electrical characteristics of InN are investigated by x-ray diffraction, scanning electron microscopy, atomic force microscopy, hotoluminescence and infrared optical absorption. The photoluminescence and the absorption studies of the materials reveal a marked energy bandgap structure around 0.70eV at room temperature. The room-temperature Hall mobility and carrier concentration of the film are typically 939cm²/Vs,
and 3.9×10¹⁸cm^-3, respectively.