Abstract

InP metal4nsulator-semiconductor field-effect transistors (MISFET) offer significant potential in high-speed digital circuits¹ and high-frequency power devices². This is due to the high saturation velocity and mobility of electrons in InP. In addition, metal-semiconductor field-effect transistors cannot be realized on Ga_0.47In_0.53 As as a result of the low Schottky barrier. The fabrication of InP MISFET’s has turned out to be difficult in the past³ due to the formation of surface defects at the dielectric-semiconductor interface. In this paper we report a novel, high-speed, ultra high transconductance Ga_0.47In_0.53 As / InP MISFET. The devices exhibit a propagation delay of 25 ps/stage and extrinsic dc transconductances as high as 320 mS/mm for a gate length of 1 μm. These are to our knowledge the highest transconductance and the lowest propagation delay measured with an FET on an InP substrate. High-speed digital circuits based on these MISFET’s are capable of operating at 5 GHz.

© 1987 Optical Society of America