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.
Keywords: InxGa1-xAs-based laser heterostructures; (001)GaAs substrate; (001)InP substrate; critical thickness; bow.
full paper (pdf, 1280 Kb)