Anomalous temperature variation of the thermal resistivity of GaAs IMPATT diodes

The thermal resistivity of GaAs IMPATT diodes was measured from 100-325 degrees C and showed an unexpected 10% decrease, in contrast with the behavior of GaAs MESFET devices, whose resistivity increases as much as 30% over the same temperature range. The most likely explanation of this unusual effect is the dominance of charged impurity scattering in a degenerately doped GaAs contact layer. This may be expected to occur in other devices where heat flow crosses highly doped regions.<
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