MULTILAYER STRUCTURE WAFER HAVING THICK SACRIFICIAL LAYER USING POROUS SILICON OR POROUS SILICON OXIDE, AND MANUFACTURE OF THE WAFER

摘要

PROBLEM TO BE SOLVED: To provide a multilayer structure wafer having a thick sacrificial layer. ;SOLUTION: A porous silicon layer or a porous silicon oxide layer is used as a sacrificial layer. In the manufacture of suspension structure, such as a semiconductor actuator and semiconductor inertia sensor, a sufficient interval can be ensured between a substrate and the suspension structure. After a P+-type or N+-type wafer which are subjected to high density doping is prepared, the surface is subjected to anodic reaction, thereby simply obtaining a thick porous silicon layer. When polycrystalline silicon 5 is grown on the porous silicon layer by epitaxial process, it is made to grow more rapidly than the growth of single-crystal silicon.;COPYRIGHT: (C)2000,JPO