Differential pressure sensor produced using bulk micro-machining using CMOS or bipolar production technology so that an analysis circuit is readily integrated with it, reducing production costs

摘要

Micro-machined differential pressure sensor comprises a substrate (1) with a hollow space (3) on one side of a main surface (2). The space is delimited by a movable membrane (4), a doped silicon wall (6) and an isolating layer (5). An opening (12), which is connected to a medium at a second pressure, connects to a channel (13) linking it to the hollow space. The hollow space, movable membrane and doped wall form a capacitor that is used to measure differential pressure. An analysis circuit is formed on the main surface of the pressure sensor.