1/f noise in all-epitaxial metal-semiconductor diodes

In contrast to traditional metal-semiconductor (i.e., Schottky) junctions, molecular beam epitaxy (MBE)-grown ErAs:InAlGaAs heterojunctions have recently been shown to provide highly "engineerable" electrical rectification characteristics through the tuning of the Schottky barrier height, while maintaining the very low specific capacitance. This letter reports an approximate 10x improvement in the low-frequency noise performance by using MBE-grown ErAs as the Schottky contact instead of evaporated aluminum. The low-frequency noise power spectrum of ErAs devices has been observed to have a 1/f(1.0) frequency dependence. Constant-current bias-dependent measurements have shown a 1.8 power law dependence of the noise spectral density on dc current. (c) 2006 American Institute of Physics.