Gigahertz logic based on InP metal-insulator-semiconductor field-effect transistors by vapor phase epitaxy

We report a high-speed inverter circuit based on novel enhancement-mode InP metal-insulator-semiconductor field-effect transistors. The devices exhibit an extrinsic transconductance as high as 320 mS/mm at room temperature. Utilizing electro-optic sampling we have measured the propagation delay of the field-effect transistors to be as short as 15 ps/stage at room temperature. These are the highest transconductance and the shortest propagation delay measured with a field-effect transistor on an In-P substrate. Furthermore, the propagation delay measured in this work is comparable to those obtained with GaAs/AIGaAs selectively doped heterojunction transistors at similar temperature.