| 摘要 |
PURPOSE:To simplify the manufacturing process and to improve the yield, by epitaxially growing silicon selectively on a single crystal silicon island in a self-aligning manner, and then removing an anti-reflecting film and a polysilicon film so as to leave the single crystal silicon island on an insulation layer. CONSTITUTION:An anti-reflecting film is composed of an SiO2 film 3 and a silicon nitride film 4. Silicon is then epitaxially grown selectively such that it is deposited only on a single crystal silicon island region 12a to form a silicon film 5 but not on the silicon nitride film. The silicon film 5 is deposited to a thickness somewhat larger than that of a polysilicon film. The silicon nitride film 4 is etched with a boiled phosphoric acid and, subsequently, the SiO2 film 3 is removed with a fluoric-acid-type etchant. After that, plasma etching is carried out with the use of CF4 gas so as to remove the polysilicon film 2 and the epitaxially grown silicon film 5. When these etching operations are terminated, the single crystal silicon island 2a is left, thereby placed in a completely isolated state. |
