We present a new single-chip diaphragm-type Fabry-Perot microcavity pressure sensor with a novel single deeply corrugated diaphragm. Both analytical and experimental results have shown that some common issues, such as signal-averaging effect and cross-sensitivity to temperature with diaphragm-type Fabry-Perot microcavity pressure sensors, can be substantially alleviated by the proposed technique.
In this study, an analytical model, taking into account the coupled photoelastic and thermal-optical effects, is established to evaluate the temperature dependence of a single-chip silicon micromachined Fabry-Perot pressure sensor. The results show that temperature variation has significant impact on the micromachined Fabry-Perot pressure sensor with conventional flat diaphragm. A new membrane-type silicon micromachined Fabry-Perot pressure sensor with a novel deeply corrugated diaphragm is then proposed. The sensor is fabricated on a single-chip using both surface- and bulk-micromachining techniques. Both analytical and experimental results show that the cross-sensitivity to temperature of Fabry-Perot pressure sensors, can be substantially alleviated by the proposed single deeply corrugated diaphragm/mirror.