n- and p-type in-plane gated field effect transistors directly written on a semi-insulating GaAs substrate

A new type in-plane gated field effect transistor where the semi-insulating substrate itself is used as a gate insulator region is proposed. n- and p-type in-plane gated field effect transistors are fabricated on a semi-insulating GaAs substrate by focused ion beam scanning of Si++ and Be++, respectively. These in-plane gated field effect transistors are found to operate well at room temperature.