Patent ID: 8490495

Claim:
A sensing device, comprising: a first sensing element disposed over a semiconductor die and configured to generate a first sensing signal upon detecting pressure; a second sensing element disposed over the semiconductor die adjacent to the first sensing element, and configured to generate a second sensing signal upon sensing ambient conditions; and a sensing circuit coupled to the second sensing element and capable of generating a pressure sensing signal in response to the first sensing signal and the second sensing signal; wherein the first sensing element includes a pressure diaphragm formed with flexible material able to deflect under pressure and functioned as a first capacitor electrode, a gap situated adjacent to the pressure diaphragm able to alter its physical shape in response to the pressure, a silicon pillar disposed on one side of the gap opposite from the pressure diaphragm, and a second capacitor electrode formed by directly doping in bottom doped sidewall of the silicon pillar adjacent to the gap via a doping process.