Semiconductor device

Abstract

Abstract PURPOSE:To produce an LDD-structure MOS transistor with its sidewall oxide film not less than 0.2mum thick by a method wherein the thickness of a polycrystalline silicon film to be a gate electrode is built not to be smaller than a specified value. CONSTITUTION:A gate oxide film 12 is formed on the primary surface of a semiconductor silicon layer 11, and a gate polycrystalline silicon film 13 is formed on the gate oxide film 12 and serves as a mask in a process wherein low concentration source.drain regions 16 are formed. A silicon oxide film is formed to cover the gate polycrystalline silicon film 13, the silicon oxide film is removed by reactive ion etching, a silicon oxide film 14 is formed on the sidewalls of the gate polycrystalline silicon 13, and then high-concentration source.drain regions 17 are formed. In a semiconductor device of this design, the gate polycrystalline silicon layer 13 is 3500Angstrom thick or more, which allows the width of the sidewall oxide film to be more than 0.2mum. Under the conditions, the transistor breakdown voltage may be kept at a high value while the leakage current is kept at a low value.

Inventors

• 👤 Kunihiro Takahashi
• 👤 邦博 高橋
• 👤 Koji Kakiuchi
• 👤 宏司 垣内

Bibliographic Details