Minority carrier lifetimes in 1.0-eV p-In0.27Ga0.73As layers grown on GaAs substrates

Time-resolved photoluminescence (TRPL) measurements indicated minority carrier lifetimes of 15 ns for electrons in 2-μm thick layers of 1.0-eV p-In_0.27Ga_0.73As grown on 6-inch GaAs wafers. Electron lifetimes increased from 10 ns to 15 ns as the thickness of 1.0-eV p-In_0.27Ga_0.73As was increased from 0.5 μm to 2 μm. The electron lifetimes decreased from 15 ns for a p-In_xGa_1-xAs with a doping density of 1×10¹⁷ cm^-3 to 5 ns for a doping density of 5×10¹⁷ cm^q̑3. Cathodoluminescence imaging measurements indicated dislocation densities of 7.9×10⁵ cm^-2 for a 1.0-μm thick layer of p-In_0.27Ga_0.73As (1.0eV) at the center of the wafer and 1.4×10⁶ cm^-2 towards the edge. Cross-section transmission electron microscopy studies were performed to study dislocation blocking and threading dislocation propagation through the metamorphic graded AllnGaAs layers.