PURPOSE: To provide a miniature semiconductor differential pressure sensor having protective function for diaphragm in which a microgap can be obtained between a diaphragm and an excess pressure stopper member.
CONSTITUTION: Two fluid pressure detecting diaphragms 2, 3 and a stopper member 1a comprising a semiconductor substrate 1 opposing the diaphragms 2, 3 through a microgap are formed integrally in a common semiconductor chip and piezogauge resistors 7-10 are disposed, respectively, in first and second gaps 4, 5 formed between the diaphragms 2, 3 and the stopper member 1a. The gaps 4, 5 are provided by forming a semiconductor layer for providing the diaphragms 2, 3 on the semiconductor substrate 1 and then removing a semiconductor layer previously formed on the semiconductor substrate 1 by etching.
SHIMADA SATOSHI
AOKI KENICHI
HIDA TOMOYUKI
YAMAMOTO YOSHIKI
NAGASU AKIRA
