Abstract: A field effect transistor is provided wherein conductive mesas are topped by source and drain electrodes, respectively, and rise out of a semiconductor epitaxial layer onto which there is formed a Schottky barrier layer. A heat sink metal layer backs the barrier layer and forms a gate terminal for control of flow of current between the source and drain electrodes via the epitaxial layer adjacent to the barrier.

Abstract: The specification discloses a low noise parametric amplifier for use with a radar receiver. A Gunn diode oscillator is provided to generate a pump frequency. A bandpass filter filters the pump frequency and applies the pump power through a waveguide having a reduced height portion employing a multisection Chebycheff transformer. A coaxial signal input line connects through the waveguide to a coaxial idler section which is provided to terminate the signal input line and to match the signal and idler frequencies. A varactor diode assembly is mounted on the center conductor of the signal input line and the idler section. A cup member is attached to the diode assembly for matching the parallel resonance of the diode assembly to the pump frequency.

Abstract: A field effect transistor wherein at least one of source, drain and gate electrodes on a semiconductor substrate is a multi electrode array above a common conductor on the bottom of the substrate. A conductive connection between electrodes of the array and the common conductor is completed through holes in the substrate.