Diamond film field effect transistor

Abstract

Disclosed is a diamond film field effect transistor incorporating a p-type semiconducting diamond layer of a specific thickness and B-doping concentration, which has a sufficiently large modulation of the gate voltage dependent current flowing between the source electrode and the drain electrode and whose transistor characteristics are not deteriorated even if adsorption of moisture occurs. Specifically, the diamond film field effect transistor includes; an active layer formed of a p-type semiconducting diamond wherein the concentration of a p-type impurity in the range between 10.sup.17 /cm.sup.3 and 10.sup.20 /cm.sup.3 and the film thickness is 0.14 .mu.m or less; and a gate electrode formed on the p-type semiconducting diamond active layer through an insulating layer. Further, conductive diamond layers are respectively formed between the p-type semiconducting diamond active layer and a source electrode, and between the p-type semiconducting diamond active layer and a drain electrode; and the electrically insulating diamond layer is deposited such that it also covers part of the conductive diamond layers.

Dependencies are inferred from the claim text.