ELECTRICALLY ISOLATED METAL-SEMICONDUCTOR FIELD-EFFECT TRANSISTORS AND LOGIC-CIRCUITS ON HOMOEPITAXIAL DIAMONDS

Isolated metal-semiconductor field effect transistors (MESFETs) have b een fabricated on homoepitaxial diamonds grown by microwave plasma che mical vapor deposition. Source, drain and channel regions are fabricat ed using the surface p-type semiconductive layer unique to hydrogen-te rminated diamond surfaces. Other areas are irradiated by an argon beam to obtain highly resistive regions. The maximum transconductance of t he isolated MESFETs with 7 mu m gate length is 4.5 mS/mm, which is com parable to that of silicon MOSFET with the same gate length. NOT, NAND , NOR, and R-S flip-flop circuits have been fabricated for the first t ime on diamond using enhancement-mode active loads.