Original Paper
In-situ Determination of the Carrier Concentration of (001) GaAs by Reflectance Anisotropy Spectroscopy
First published: 14 December 2001
Citations: 20
Abstract
We demonstrate the use of Reflectance Anisotropy Spectroscopy (RAS) to determine the carrier concentration in GaAs of the topmost layers (≈20 nm) in-situ during layer growth. The doping contributes to three features in the RAS spectra: an oscillation at E1/E1 + Δ1, an oscillation at E0′/E0′ + Δ0′ and an offset of the baseline of the whole spectrum. Using the empirical calibration in this paper, carrier concentrations above ≈1017 cm—3 can be easily measured by RAS for a given temperature, dopant and reconstruction.
