Patent ID: 7404330

Claim:
A pressure sensor comprising: a metal housing including a diaphragm and an inlet for introducing fluid to be sensed to the diaphragm, the diaphragm being unitary with the housing, the inlet having a first end exposed to the diaphragm and a second end exposed to an outside of the housing; and a semiconductor chip mounted on the diaphragm, the chip including a strain gauge for producing an electrical signal corresponding to deformation of the diaphragm, the deformation being caused by pressure of the fluid, wherein a double logarithmic relationship between shear stress T acting at an interface between the semiconductor chip and the diaphragm and distance X from an outer edge of the interface is given by the following equation: T=KX 0.4 where K is a parameter, and area and thickness of the semiconductor chip are set so that the parameter K is less than or equal to 17.