An improved microwave silicon MESFET

Abstract

An improved silicon MESFET with a 1; gate is described which has a maximum frequency of oscillation of 15 GHz. The improvement over previous MESFET's has been achieved by reducing the influence of the resistance of the gate metallization and by decreasing the gate-pad parasitics. Maximum available gain MAG is now 5 dB at 7 GHz and the optimum noise figure F0 is 5 dB at 6 GHz. Below about 6 GHz the device is conditionally unstable. Unilateral gain U up to 3 GHz is 20 dB. The investigation indicates that not all parasitics have been removed. If the series resistance of the channel in the source-gate spacing could be decreased, fmax should approach 35 GHz the estimated value of the intrinsic transistor. © 1971, Pergamon Press Ltd.. All rights reserved.