Threading Dislocation Blocking in Metamorphic InGaAs/GaAs for Growing High-Quality In$_{0.5}$Ga$_{0.5}$As and In$_{0.3}$Ga$_{0.7}$As on GaAs Substrate by Using Metal Organic Chemical Vapor Deposition

Abstract

High quality In0.3Ga0.7As and In0.51Ga0.49As epilayers have been successfully grown on the GaAs substrate by MOCVD. A cross-sectional study by transmission electron microscopy showed that the threading dislocations (TDs) have been successfully contained and limited within the buffer layers designed to stop the elongation of TDs into the In0.3Ga0.7As and In0.51Ga0.49As epilayers. A TD density of 1×106 cm-2 in a fully relaxed In0.51Ga0.49As epilayer was achieved. The measurement of lifetimes of n- and p-type In0.51Ga0.49As has been done by using time-resolved photoluminescence. A great reduction in the number of recombination centers in the InGaAs epilayer has been shown.