Pressure sensor for tire of vehicle, has deformable membrane with insulant material layer, and resistive gauge integrated to insulant material layer and situated below membrane inside cavity which is closed by substrate and membrane

摘要

#CMT# #/CMT# The sensor has a cavity (V) hermetically closed at the bottom by a semiconductor substrate (40) and at the top by a deformable membrane (58) under the effect of outer pressure at the cavity. The sensor has resistive gauges (54, 56) integrated to the membrane and has a variable resistance value according to the deformation of the membrane. The membrane has an insulant material layer, and the gauge integrated to the insulant material layer is situated below the membrane inside the cavity. #CMT# : #/CMT# An independent claim is also included for a method of fabricating a pressure sensor. #CMT#USE : #/CMT# Used in microelectronics technology, for measuring atmospheric pressure and pressure of tire of vehicles. #CMT#ADVANTAGE : #/CMT# The resistive gauge is integrated to the material layer situated below the membrane inside the cavity, so that the cavity covers the major parts of the circuit associated to the gauge, thus avoiding the need for the electronic circuits of the sensor outside the cavity on the substrate, so that the sensor is easy to realize and is inexpensive. #CMT#DESCRIPTION OF DRAWINGS : #/CMT# The drawing shows a lateral sectional view of a structure of a pressure sensor. V : Cavity 40 : Semiconductor substrate 42 : Superficial zone 54, 56 : Resistive gauges 58 : Deformable membrane #CMT#METALLURGY : #/CMT# The gauges are made of nickel/copper/silicon alloy or nickel/copper/manganese alloy.