| 摘要 |
PURPOSE:To obtain an LSI with a channel of minute length by a method wherein a thin Si film is grown on the insulated substrate, the thickness of the film is more reduced in the central part thereof, a transistor region is formed therein, and the films located on both sides of the region are employed as regions for leading out electrodes. CONSTITUTION:The p type thin Si film 30 is grown on the insulated substrate formed on sapphire and the like, is covered with SiO2 films 351 and 352 of a prescribed pattern, and the thin film 30 is left like islands, through etching, as a region 301'' scheduled for forming an MOS transistor and a region 302'' scheduled for forming a wiring, while the remaining part is removed. Next, the selective etching is applied only to the central part of the islandlike layer 301'' to obtain further a thin layer 301', the films 351 and 352 are removed, thus an SiO2 film 36 is formed only on the layer 301', and the whole surface inclusive of the film 36 is coated with a PSG film. After that, the impurities in this film are diffused through heat treatment, the region 301'' and 302'' are transformed into the type on n<+>, the PSG film and the SiO2 film are removed, and within the layer 301' an n type source region 31 and a drain region 32 holding the p type region between them are formed diffusely. |
