Schottky Barrier Height Determination by Capacitance-Voltage Measurement on n-GaN with Exponential Doping Profile

Abstract

A capacitance–voltage (C–V) method was developed to extrapolate the Schottky barrier height on n-GaN with exponential carrier concentration profile. The carrier concentration profile of the unintentionally doped GaN was determined by C–V measurement to be exponential. On the basis of this profile, one-dimensional Poisson's equation was calculated to obtain the relation between bias voltage and depletion width. Schottky barrier height was obtained by fitting the curves of 1/C2 and V with the experimental one, using the Schottky barrier height itself as a fitting parameter.