Integrated amplifiers using fully ion-implanted InP JFETs with high transconductance

Abstract

Monolithically integrated amplifiers have been fabricated on indium phosphide (InP) using fully ion-implanted JFETs. The FETs have a gate length of 1.5 pm and a maximum transconductance of 110 mS/mm, the highest ever reported for ion-implanted InP JFETs. The amplifiers utilized both a conventional direct-coupled design as well as a new symmetrical design. The conventional direct-coupled amplifier shows a maximum gain of 8 (18 dB) while the symmetrical amplifier design exhibits the same gain without dc offset regardless of the FET threshold voltage and the power supply voltage used.