US 12,339,191 B2
Pressure sensor chip, pressure sensor, and manufacturing method thereof
Daiki Tsuji, Nagaokakyo (JP)
Assigned to MURATA MANUFACTURING CO., LTD., Kyoto (JP)
Filed by Murata Manufacturing Co., Ltd., Nagaokakyo (JP)
Filed on Jan. 5, 2023, as Appl. No. 18/093,349.
Application 18/093,349 is a continuation of application No. PCT/JP2021/025839, filed on Jul. 8, 2021.
Claims priority of application No. 2020-131925 (JP), filed on Aug. 3, 2020.
Prior Publication US 2023/0146603 A1, May 11, 2023
Int. Cl. G01L 13/02 (2006.01); G01L 9/00 (2006.01); G01L 9/12 (2006.01)
CPC G01L 9/0072 (2013.01) [G01L 13/026 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A pressure sensor chip comprising:
a first diaphragm and a second diaphragm to measure pressure;
a base;
a first layer including a first cavity and joined to the base;
a second layer joined to a surface of the first layer opposite to the base;
a third layer including a second cavity and joined to a surface of the second layer opposite to the first layer; and
a fourth layer including a third cavity and joined to a surface of the third layer opposite to the second layer; wherein
the second layer includes the first diaphragm between the first cavity and the second cavity;
the fourth layer includes the second diaphragm between the second cavity and a space in communication with outside;
a first end of the third cavity is in communication with outside;
a second end of the third cavity is in communication with the second cavity; and
the first cavity is sealed and a pressure in the first cavity is lower than a pressure in the second cavity.