Critical thickness and bow of pseudomorphic InxGa1-xAs-based laser heterostructures grown on (001)GaAs and (001)InP substrates


Using the energy-balance approach, we have estimated critical thickness for misfit dislocation (MD) formation and wafer bow for single- and multi-layer InGaAs-based pseudomorphic heterostructures used in light-emitting devices. Indicating the onset of stress relaxation via MD formation, the analysis of critical thicknesses serves as a guideline for device structure design avoiding extensive defect generation usually accompanying the relaxation. Estimates of structure bow are helpful for meeting requirements of the wafer post-growth processing technology. Suggested methodology may be applied to optimization of strain-compensated semiconductor laser heterostructures.