Electrical transport characteristics of Au/n-GaAs Schottky diodes on n-Ge at low temperatures

The current-voltage characteristics of Au/n-GaAs Schottky diodes grown by m etal-organic vapor-phase epitaxy on Ge substrates were determined in the te mperature range 80-300 K. The zero-bias barrier height for current transpor t decreases and the ideality factor increases at low temperatures. The idea lity factor was found to show the T-o effect and a higher characteristic en ergy. The excellent matching between the homogeneous barrier height and the effective barrier height was observed and infer good quality of the GaAs h im. No generation-recombination current due to deep levels arising during t he GaAs/Ge heteroepitaxy was observed in this study, The value of the Richa rdson constant was found to be 7.04 A K-2 cm(-2), which is close to the val ue used for the determination of the zero-bias barrier height. (C) 2001 Els evier Science Ltd. All rights reserved.