Silicon Micromachining

2. Pressure sensor and resonant gyro fabricated using deep RIE and XeF2 etching. Small diameter (1 25 pn6) fiber optic pressure sensor(Fig.1) has been developed. Thin diaphragm is formed at the end of an optical fiber and the deformation by the pressure is detected interferometrically. Silicon rod which has a diaphragm is made by the deep RIE and is bonded to the fiber end. Finally silicon is etched out with XeF, gas. The resonant gyro shown in Fig.2 was fabricated using the deep RIE, side wall oxidation and the XeF2 silicon etching.