PRESSURE SENSOR HAVING MULTIPLE PRESSURE CELLS AND SENSITIVITY ESTIMATION METHODOLOGY

摘要

A pressure sensor (20) includes a test cell (32) and sense cell (34). The sense cell (34) includes an electrode (42) formed on a substrate (30) and a sense diaphragm (68) spaced apart from the electrode (42) to produce a sense cavity (64). The test cell (32) includes an electrode (40) formed on the substrate (30) and a test diaphragm (70) spaced apart from the electrode (40) to produce a test cavity (66). Both of the cells (32, 34) are sensitive to pressure (36). However, a critical dimension (76) of the sense diaphragm (68) is less than a critical dimension (80) of the test diaphragm (70) so that the test cell (32) has greater sensitivity (142) to pressure (36) than the sense cell (34). Parameters (100) measured at the test cell (32) are utilized to estimate a sensitivity (138) of the sense cell (34).

主权项

1. A method of determining a sensitivity of a pressure sensor comprising:
measuring an ambient pressure using a pressure measurement device in lieu of said pressure sensor; determining a first sense signal between a first electrode and a sense diaphragm of a sense cell of said pressure sensor at said ambient pressure; determining a second sense signal between a second electrode and a test diaphragm of a test cell at said ambient pressure; estimating said sensitivity of said pressure sensor using said measured ambient pressure, and said first and second sense signals.