Patent ID: 9738508
Date: 2017-08-22
CPC Classifications: B81B,B81C,G01L,H01L

Claim:
1. A MEMS capacitive pressure sensor, comprising: a substrate having a first region and a second region surrounding the device region; a first dielectric layer formed on the substrate; a second dielectric layer having a step surface profile formed on the first dielectric layer; a first electrode layer having a step surface profile formed on the second dielectric layer and the first dielectric layer; an insulation layer formed on the first electrode layer; a second electrode layer having a step surface profile with a portion formed on the insulation layer in the peripheral region and the rest suspended over the first electrode layer in the device region; and a chamber having a step surface profile formed between the first electrode layer and the second electrode layer, wherein a projection of the step surface profile of the second dielectric layer on the substrate is a plurality of concentric circles, a plurality of concentric squares or a plurality of concentric polygons.