A novel camel diode gate GaAs FET

Abstract

A novel device utilizing the "camel diode" in place of a Schottky barrier gate has been demonstrated in GaAs grown by molecular beam epitaxy (MBE). The devices have a 7.5 µm channel length, 3 µm gate length, and a 280 µm gate width. The layers from which the devices are fabricated consist of a 0.15 µm GaAs layer doped to a level of 1.5 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">17</sup> cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-3</sup> to form the channel, and a 100 Å p+GaAs and a 400 Å n+ region to form the gate. Because of the long gate length, the electron velocity does not reach saturation, thus a transconductance of 80 mS/mm is obtained. A simple theory describing the device operation has also been developed.