Pressure sensor and method of manufacturing pressure sensor
AssigneeHitachi Unisia Automotive, Ltd.
InventorsMasao Tsukada, Koichi Kusuyama
Life of this patent
Estimating the term…
Abstract
In a pressure sensor in which a frame shaped protruding potion is formed on a surface side of a substrate by means of an etching process, and a blocking plate is connected to an upper part of the protruding portion, to form a standard pressure chamber, a recess is formed on at least one of the substrate and the blocking plate that constitute the standard pressure chamber, to increase the height of the standard pressure chamber, thereby preventing the lowering of pressure detection accuracy due to foreign substances within the standard pressure chamber.
Claims18
A pressure sensor comprising:
- a substrate formed of silicon material, in which a pressure receiving recess is formed on a rear face thereof to provide a thin portion on a surface side thereof, and also a frame shaped protruding portion is formed on a surface side of said thin portion;
- a blocking plate connected to an upper part of the frame shaped protruding portion of said substrate, to block space surrounded by said frame shaped protruding portion;
- and
- a deflection detecting element that detects deflection of said thin portion surrounded by said frame shaped protruding portion,
- wherein a recess for increasing the height of the space surrounded by said frame shaped protruding portion is formed on at least one of a surface of said thin portion surrounded by said frame shaped protruding portion and a rear face of said blocking plate.
A manufacturing method of a pressure sensor, comprising the steps of:
- forming a pressure receiving recess on a rear face of a substrate;
- forming a frame shaped protruding portion on a surface side of a thin portion that is provided on said substrate by forming said pressure receiving recess;
- forming a deflection detecting element on said thin portion surrounded by said frame shaped protruding portion;
- connecting a blocking plate to an upper part of the frame shaped protruding portion;
- and
- forming a recess for increasing the height of space surrounded by said frame shaped protruding portion on at least one of a surface of said thin portion surrounded by said frame shaped protruding portion and a rear face of said blocking plate.
Dependencies are inferred from the claim text.