1/f noise of GaAs resistors on semi-insulating substrates, and 1/f noise due to temperature fluctuations in heat conduction

Abstract

This research work focuses on the mechanism of 1/f noise in GaAs resistors on semi-insulating substrates and 1/f noise due to temperature fluctuations in heat conduction in resistors, diodes, and bipolar transistors. The goal of this research is to generate accurate models to explain physical origin of 1/f noise in semi-insulating substrate and semiconductor devices dissipating high power. The model is based on a distributed equivalent circuit representation of the substrate, and shows that 1/f noise bulk phenomena associated with high resistivity substrates. One consequence of the theory is that in this particular instance Hooge's parameter is given by a formula and it is not an empirical parameter. Power dissipation at high currents and voltages in semiconductor devices results in significant heat generation and heat conduction towards the heat sink. The device temperature is only an average value and there are as a consequence of the diffusion equation for heat flow itself temperature fluctuations about this average value. It will be shown that these temperature fluctuations can result in 1/f noise at moderately low frequencies where these frequencies are determined by the physical dimensions over which the heat flows and the diffusion transit time. The results are then related to the shot noise or white noise due to the collector current allowing a determination of the 1/f noise corner frequency.