SEMICONDUCTOR PRESSURE SENSOR

摘要

It is possible to provide a semiconductor pressure sensor having a small relative position shift between a diaphragm and a sensitive resistance element or a small shape error of the diaphragm, and suppressing generation of a measurement error. The semiconductor pressure sensor includes: a cavity (20) formed on one (13) of the silicon substrates bonded to sandwich an oxidization film (12) to constitute an SOI substrate (10); and a diaphragm (21) formed by the other substrate (11) and the thermal oxidization film (12). The thermal oxidization film (12) of the diaphragm (21) facing the cavity (20) has the same diameter as the cavity defined by the silicon substrate (13) at the boundary with the silicon substrate (13) regulating an inner wall surface (13a) of the cavity (20) and has a cross section of an arc shape having a smaller diameter defined by the cavity diameter from the boundary toward the center of the diaphragm (20).