Band offset determination in parabolic and triangular quantum wells of GaAs/AlGaAs and GaInAs/AlInAs

The band offset parameter Qc≡ΔEc/ΔEg for both GaAs/AlGaAs, and GaInAs/AlInAs (lattice matched to InP) was extracted from electron beam electroreflectance interband transition energies obtained from molecular‐beam epitaxially grown parabolically and triangularly shaped quantum wells (QWs). Most of the QWs were grown using continuous analog grading. Additionally, for comparison, two 500 A GaAs/AlGaAs, superlattice (digitally) graded, parabolic QWs, with bilayer thicknesses of 25 and 12.5 A, were also evaluated. Qc values obtained were 0.661±0.015 and 0.650±0.005 for GaAs/AlGaAs and GaInAs/AlInAs, respectively. Measurements also revealed that Qc was both temperature and concentration independent.