| 摘要 |
PURPOSE:To make the density and distribution of porous silicon uniform and to prevent the occurrence of warping, by forming a silicon island region, in which an element region is not formed, in a part other than the silicon island region, which becomes the element region. CONSTITUTION:In addition to a silicon island region 5, which becomes an element region as shown in Figure (a), a silicon island region 5'' [Figure (b)] other than the element region is simultaneously formed. At this time, the silicon island region 5'' other than the element region 5' is formed so that an approximately equal pattern occupying rate and pattern distribution are provided, even when a semiconductor device having a different element region is manufactured as shown in Figure (b). At this time, the pattern occupying rate of about 30 deg. is suitable. The conventional occupying rate is about 25% at the highest. A good result is obtained when the rate is slightly higher than that value. The silicon island region 5'', which is not used as the element, is removed by dry etching as shown in the Figure, and the next process is performed only for the element region 5'. |
