Optical and transport properties of MOCVD-grown InSb thin films

Abstract

In this work we present optical investigations of metalorganic chemical vapor deposition (MOCVD) grown InSb thin films on GaAs(100) substrates and MeV ion implanted InSb(111) bulk crystals. Far-infrared (FIR) reflectance spectroscopy has been used to study the lattice vibration behavior of all the samples. For the MOCVD films the effects of III-V source ratios on the films crystalline quality may have been reported. Two additional weak modes in the wavenumber regions of 210-240 cm -1 are observed and they appeared more prominent at low temperatures. Interference fringe effects modify the FIR reflectance band of the GaAs substrate. They are related to the uniformity of film thickness and crystalline perfection. The relationship between these interference features and film quality as well as thickness uniformity was obtained from the measured spectra. The carrier concentration, mobility, effective mass as well as the dielectric constant of these films have been determined. For the bulk InSb crystals, high energy C + ions have been implanted and MeV energies and, the optical as well as transport properties of the implanted layers have been presented and discussed.