Method for making diaphragm-based sensors and apparatus constructed therewith

摘要

A diaphragm transducer 201 is manufactured by forming cavities in a diaphragm layer which are backfilled with a material readily removed by etching. The diaphragm layer is bonded to a silicon wafer. Access passages are provided to enable removal of the backfill material. The transducer 201 is incorporated in a three-wafer capacitive sensor 4 bonded to a pressure tube 5 with pressure ports 204 and 205 leading to access pressure ports 206. <IMAGE>