Reduction of threading dislocation density in metalorganic-chemical-vapor-deposition-grown GaAs layer on Si substrate by In-doping

摘要

We have grown 5 μm thick GaAs layers on Si substrates by low-pressure metal-organic chemical vapor deposition. We attempted to suppress the influence of thermal strain generated during cooling stage by indium doping in the final GaAs layer. Photoluminescence measurements and cross-section transmission electron microscopy were performed to investigate the residual strain of the InGaAs layer. It was confirmed that the In-doping was effective in reducing the influence of thermal strain. A low threading dislocation density of 6×10{sup}5 cm{sup}(-2) was achieved by combination of high temperature thermal cycle annealing and In doping.