| 摘要 |
PURPOSE:To realize a semiconductor pressure sensor that the sensor element itself is substantially superior in insulating property and atmosphere resistance by a method wherein, in the formation of the pressure sensor, which utilizes the piezoresistance effect of a semiconductor, the minimum necessary semiconductor layers only are used for covering the surface thereof and single crystal insulators such as a sapphire are used for covering the other parts other than the surface. CONSTITUTION:A diaphragm part 2 consisting of only single crystal silicon epitaxial growth layers (N<-> type) 7 and 10 and an insulating layer (example, a multilayer structure of SiO2 and Si3N4) 4 is provided without containing sapphires 9 at all, while a diffusion piezoresistance part (P<-> type) 3 and a diffusion lead part 6 are provided between the single crystal layers 7 and 10. The diffusion lead part 6 is designed so as to be conducted to Al wiring layers 5, which have been separated from each other by the insulating layer 4, through P<+> type diffusion regions 8. By constituting in such a structure, most of the surface of the sensor element is covered with the single crystal insulative substrates 9 and insulative substances such as the insulating layer 4 and insulating layers 11, and substances having a conductivity among the substances, which are used for covering the surface, are only the Al wiring layers 5 and the N<-> type silicon layers appearing slightly on the side. |
