Rectifying properties of solid C 60/n-GaN, C 70/n-GaN and C 70/p-GaN heterojunctions

Abstract

Current-voltage measurements show that C 60/n-GaN, C 70/n-GaN and C 70/p-GaN contacts have very good rectification characteristics, however, the polarities of the forward biases for C 60/n-GaN (C 70/n-GaN) and C 70/p-GaN are opposite to each other. By fitting forward current-voltage data, the relations of both the series resistance and ideality factor vs forward bias for C 60/n-GaN and C 70/n-GaN have been obtained. Thermal activation measurements at a fixed forward bias reveal exponential relations of currents vs the reciprocal of temperature. The effective barrier heights for C 60/n-GaN and C 70/n-GaN are determined to be 0.535 and 0.431 eV, respectively.