EFFECTS OF H-PLASMA PASSIVATION ON THE OPTICAL AND ELECTRICAL-PROPERTIES OF GAAS-ON-SI

The effects of hydrogen plasma passivation on optical ana electrical p roperties of metalorganic chemical vapor deposition (MOCVD) grown GaAs -on-Si epilayers have been studied. The intensity of photoluminescence (PL) was entranced as much as four times by H plasma passivation foll owed by annealing in AsH3 ambient at 400 degrees C. The minority carri er lifetime was also increased effectively by the passivation process. Compared to the results of deep-level transient spectra (DLTS) measur ements, the improvement in optical properties appears to be a result o f the passivation of the dislocation-associated deep defects in the Ga As-on-Si epilayers by H plasma passivation. The passivation effects pe rsist even after the annealing process at 400 degrees C, which suggest s that the H plasma passivation may be a useful method for improving t he properties of the GaAs-on-Si-based devices.