Abstract: A high-power and high-gain ultra-short gate HEMT device has exceptional gain and an exceptionally high breakdown voltage provided by an increased width asymmetric recess for the gate electrode, by a composite channel layer including a thin indium arsenide layer embedded in the indium gallium arsenide channel layer and by double doping through the use of an additional silicon doping spike. The improved transistor has an exceptional 14 dB gain at 110 GHz and exhibits an exceptionally high 3.5-4 V breakdown voltage, thus to provide high gain, high-power and ultra-high frequency in an ultra-short gate device.

Abstract: A high-power and high-gain ultra-short gate HEMT device has exceptional gain and an exceptionally high breakdown voltage provided by an increased width asymmetric recess for the gate electrode, by a composite channel layer including a thin indium arsenide layer embedded in the indium gallium arsenide channel layer and by double doping through the use of an additional silicon doping spike. The improved transistor has an exceptional 14 dB gain at 110 GHz and exhibits an exceptionally high 3.5-4 V breakdown voltage, thus to provide high gain, high-power and ultra-high frequency in an ultra-short gate device.

Abstract: A high-power and high-gain ultra-short gate HEMT device has exceptional gain and an exceptionally high breakdown voltage provided by an increased width asymmetric recess for the gate electrode, by a composite channel layer including a thin indium arsenide layer embedded in the indium gallium arsenide channel layer and by double doping through the use of an additional silicon doping spike. The improved transistor has an exceptional 14 dB gain at 110 GHz and exhibits an exceptionally high 3.5-4 V breakdown voltage, thus to provide high gain, high-power and ultra-high frequency in an ultra-short gate device.

Abstract: A typical source of cadmium and tellurium is as a by-product of copper mining. Although attempts are made to remove impurities such as copper prior to commercially supplying them for forming material like cadmium telluride, cadmium zinc telluride and cadmium telluride selenide for use as a substrate to support electronic circuitry, processing during formation of the circuitry causes the impurities from the substrate to segregate into the circuitry, resulting in unacceptable electrical performance of the circuitry. A method for purifying the substrate prior to circuitry formation includes forming a sacrificial layer of mercury telluride or mercury cadmium telluride on the substrate, annealing the combination at elevated temperature with an overpressure of mercury and removing the sacrificial layer along with a contiguous portion of the substrate, if desired. The sacrificial layer may be formed by vapor phase type processes or even by liquid phase epitaxy.