| 摘要 |
PURPOSE:To form a fine pattern with a large aspect ratio, and realize high density and high performance, by a method wherein, without using a mask, ions are directly implanted into a semiconductor substrate surface, by applying a convergent ion beam to turn the implanted region into an amorphous state, and then the region is subjected to a selective etching. CONSTITUTION:A GaAs substrate 1 is linearly scanned at 0.4mum intervals by a convergent Si ion beam, and ions are implanted under conditions of an acceleration voltage of 200keV and a line dose of 3.0X10<9>cm<-1>. The depth of 0.2mum from the surface is turned into an amorphous region. By selectively etching this amorphous region with hot hydrochloric acid (70 deg.C), a diffraction grating can be formed (b). By increasing the line dose up to, for example 3.5X10<9>cm<-1>, a groove width is widen (c). The convergent ion beam is controlled by a computer, and the diffraction grating, in which the period is gradually changed and the phase is inverted, can be manufactured. Therefor, arbitrary patterns as well as lines can be drawn. |
