Estimation of doping density in low doped n-InAs by electrolyte-based capacitance-voltage measurements in the deep depletion mode

Abstract

Doping density profiling in InAs is difficult due to lack of good quality Schottky contacts and the narrow bandgap nature of the material. The electrolyte can be used to form a Schottky-like contact but the inversion layer formation does not allow obtaining a dopant concentration in low doped InAs. To overcome this issue, a pulse CV technique has been implemented to drive a sample into the deep depletion mode which makes it possible to use the depletion approximation to calculate a carrier concentration. The measured capacitance-voltage characteristics were compared with the simulation and showed good agreement with it.