Suppressing Ge diffusion by GaAsSb barriers in molecular beam epitaxy of InGaAs on Ge
Journal
Physica Status Solidi (B) Basic Research
Journal Volume
254
Journal Issue
2
Date Issued
2017
Author(s)
Abstract
We have successfully mitigated the out‐diffusion of Ge during molecular beam epitaxy of InGaAs on Ge by using a GaAsSb barrier layer as evidenced by secondary ion mass spectroscopy. Compared to GaAs, this GaAsSb barrier layer also results in a smoother surface morphology with its root‐mean‐square roughness of 0.7 nm due to the surfactant effect of Sb. Using a step‐graded GaAsSb and AlGaAsSb metamorphic buffer layer, a 200‐nm p‐type In 0.53 Ga 0.47 As layer grown on Ge exhibits a hole mobility of 38 cm 2 V −1 s −1 with a hole concentration of 2.6 × 10 19 cm −3 at 300 K and 53 cm 2 V −1 s −1 with a hole concentration of 1.2 × 10 19 cm −3 at 77 K.
Type
journal article