Insulated gate transistor with leakage current prevention feature

Abstract

An MIS transistor fabricated in a manner that minimizes the occurrence of leak currents and that improves overall transistor performance by minimizing variation in location of the transistor source and drain during fabrication thereof. A gate electrode is first fabricated on a substrate. Next, a thermal oxide layer is formed on a side of the gate electrode. A masking process is then performed with the thermal oxide layer to form a source and a drain. A silicon oxide layer is then deposited over the gate electrode, the source and the drain. An etching process is performed on the silicon oxide to form a side wall oxide film over the thermal oxide layer on the side of the gate electrode and to expose surfaces of the gate electrode, the source and the drain. A metal film is then deposited over the gate electrode, the source and the drain and is heat treated to form a metal silicide film on the exposed surfaces of the gate electrode, the source and the drain. The side wall oxide film functions to disperse the metal silicide film as it is deposited to electrically separate the gate electrode, the source and the drain, thereby preventing a leakage current from occurring.