Optical calibration of electron concentrations in heavily doped n-GaAs films

An accurate knowledge of carrier concentrations is important for many semiconductor devices. A variety of optical and electrical measurement techniques has been developed. In this paper we discuss and compare different linear reflection measurement techniques to calibrate the electron concentration N in thin n-GaAs layers in the range between 1 and 20 /spl times/ 10/sup 18/ with accuracies down to 1-2 % by exploiting optical plasma resonance effects.