A process to control diaphragm thickness with a provision for back to front alignment in the fabrication of polysilicon piezoresistive pressure sensor

A MEMS process is described to control diaphragm thickness with an integrated provision for back to front alignment in the fabrication of a polysilicon piezoresistive pressure sensor. The end point detection for the diaphragm etching is suitably incorporated in the process so that it is also used for the back‐to‐front alignment. The proposed process is cost‐effective and suitable for the batch fabrication of the pressure sensor.