| 摘要 |
PURPOSE:To reduce the depletion layer capacity of a source and a drain and to expedite the operating speed, when a minute MOS transistor is manufactured, by providing a high impurity concentration region in a channel region beneath a gate electrode. CONSTITUTION:A thick field oxide film 302 is formed in the peripheral part of a P type Si substrate 301. A thin gate oxide film 303 is provided on the area of the surface of the substrate 301 between the parts of the film 302. An N type polycrystal Si layer 304 and an SiO2 film 305 are layered deposited on the entire surface. Then the area other the channel part of the transistor is coated by a resist film 306. B<+> ions are implanted in the entire surface, and a P<+> type region 307 is formed at the channel part corresponding to the opening part in the film 306. Thereafter, heat treatment is performed in HF gas, the film 305 beneath the film 306 is dissipated, and a gate SiO2 film 8 comprising the film 305 is left over the region 307. With the film 8 as a mask, the exposed part of the Si layer 304 is etched away, and the gate electrode comprising the layer 304 is formed beneath the film 308. Thereafter, N type source and drain electrodes 309 are formed on both sides of the electrode 304 in a usual manner. |
