AgSn cathode contact in gallium-arsenide transferred-electron devices

Simple observations of the temperature dependence of the threshold current of AgSn-contacted gallium-arsenide transferred-electron devices are interpreted in terms of Schottky-barrier cathodes. From the measurements, the barrier heights are deduced and a mechanism is suggested for their formation. The consequences of the presence of the barrier on the operation of oscillators and amplifiers are discussed and illustrated by experimental results.