e-Beam electroreflectance of short-period SiGe superlattices

Abstract Electron-beam electroreflectance (EBER) has been used to investigate electronic and optical properties of short-period SiGe superlattices grown by molecular beam epitaxy on (001)Si. The advantage of the EBER method over conventional ER techniques is that no contact has to be made to the sample. The results are compared with those obtained from conventional Schottky barrier electroreflectance (SBER) measurements performed on samples taken from the same wafer. The two ER techniques give results which are in good agreement. The EBER and SBER experimental results on these SiGe superlattice samples closely match theoretically predicted transitions obtained from full-scale empirical pseudopotential calculations.