The fabrication and use of micromachined corrugated silicon diaphragms

Abstract Corrugated diaphragms offer much greater linearity and travel than the equivalent flat diaphragms. Corrugations have been, produced in silicon microstructures by etching grooves in the top surface of a wafer and diffusing an etch stop. A back-side etch is then used to form the corrugated diaphragm. Corrugations have been made between 3 and 20 μm deep with diaphragm thicknesses between 0.6 and 8 μm. A capacitive pressure sensor has been fabricated using these techniques with a full-scale sensitivity of 1 mmHg.