Optimum design of transferred-electron amplifier devices in GaAs

The paper concern the design of GaAs transferred electron amplifying diodes with a cathode doping notch. Simple analytical expressions for small signal impedance and noise factor are expressed in terms of the growth factor and transit phase angle for a constant electric field notch device. These are compared to experimental results, measured on such a device, and the agreement is remarkably good considering the simple model. A minimum measured noise figure of 10.5 dB was obtained. The gain saturation curves are given and briefly discussed. Although at higher frequencies, a small gain increase is encountered with increasing drive a properly controlled notch device does not show a marked gain jump at higher levels as is frequently encountered with Gunn amplifiers.