Semiconductor device and its process of fabrication

摘要

The multilayer semiconductor circuit (100) has a substrate (101) made of silicon. A first porous layer (104) is formed in the central part of the top surface of the substrate. A cavity may be formed under this porous layer, and the cavity may have an external opening to provide access. A second porous layer (105) may be formed under the first, with larger pores. A masking layer (102) may be formed on either side of or surrounding the porous layers.