Band alignments for pseudomorphic InP/InxGa1−xAs heterostructures for growth on (001)InP

Estimates of the anticipated band alignments for pseudomorphic InP/InxGa1−xAs heterostructures for growth on (001) InP are presented; wherein 0≤x≤1.0. Linearity and transitivity of the valence-band offset, ΔEv, are assumed for a given in-plane lattice parameter, a∥≡a0(InP). Valence-band offsets for ternary heterojunctions are obtained via linear interpolation of the self-consistent interface calculations of Van deWalle and Martin (unpublished), whereas ΔEv for the lattice matched (In, Ga) As/InP heterojunction is taken as an input parameter. It is found that ΔEc shows a rather gradual increase for 0≤x<0.53, with an abrupt change in slope for x>0.53. The present estimates imply an increase in ΔEc by more than 0.2 eV as x→1.0 relative to the lattice matched value, and that the partitioning of ΔEg between conduction and valence band in strained heterostructures maintains its lattice matched value. Potential applications are reviewed in brief.