Abstract: A method of manufacturing a semiconductor device by which an element region for electronic circuits or the like is formed on the surface of a semiconductor substrate, a diaphragm region is formed in the bottom surface of the semiconductor substrate, and a plurality of openings having different areas and shapes are formed in the semiconductor substrate. The method includes a step of forming a first diaphragm region in the bottom surface of a semiconductor substrate, a step of partially forming a second diaphragm region in the first diaphragm region, the second diaphragm region being thinner than the first diaphragm region, and a step of forming an opening by removing part or the whole of the second diaphragm region.

Abstract: A semiconductor device is produced through electrolytic etching process. The device comprises a P-type silicon substrate. An N-type epitaxial layer is formed on the silicon substrate. P-type regions are defined in the N-type epitaxial layer. N-type regions are defined in some of the P-type regions. A first wiring layer connects to predetermined ones of the P-type regions. A second wiring layer connects to predetermined ones of the N-type regions. The semiconductor device has a given part which has such a possibility that a predetermined magnitude of leakage current flows therethrough between the first and second wiring layers when subjected to the electrolytic etching process. The semiconductor device further has a circuit which is electrically connected to one of the first and second wiring layers. The circuit is capable of removing the possibility of the leakage current flow through the given part when opened.