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.
