Non-linear As(P) incorporation in GaAs1−yPy on GaAs and InAs1−yPy on InP

We find anion incorporation into both GaAs_1−yP_y on GaAs and InAs_1−yP_y on InP during gas source molecular beam epitaxy (GSMBE) is not linearly related to the hydride gas fluxes within our reactor. The deviation from an ideal model, i.e., y = ƒ_P/(ƒ_P+ƒ_As), where As(P) is the flux of AsH₃ (PH₃), can be as large as a factor of two. GaAsP exhibits the largest degree of nonlinearity and incorporation is found to depend quadratically on the fluxes over a wide range of flux ratio. Significant deviations are also found for InAsP; however, anion incorporation can be modeled with y = ƒ_P/(ƒ_P+βƒ_As).