Thick oxide P-gate NMOS capacitor for use in a low-pass filter of a circuit and method of making same
US8148219B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 15, 2009 |
| Grant date | Apr 3, 2012 |
| Priority date | — |
| Expiry date | Jul 8, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D1/66
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A circuit with dielectric thicknesses is presented that includes a low-pass filter including one or more semiconductor devices having a thick gate oxide layer, while further semiconductor devices of the circuit have thin gate oxide layers. The low-pass filter semiconductor device includes an N-type substrate, a P-type region formed on the N-type substrate, a thick gate oxide layer formed over the P-type region, a P+ gate electrode formed over the thick gate oxide layer and coupled to a first voltage supply line, and P+ pick-up terminals formed in the P-type region adjacent the gate electrode and coupled to a second voltage supply line. The low-pass filter semiconductor device acts as a capacitor, whereby a gate-to-substrate voltage is maintained at less than zero volts to maintain a stable control voltage for the circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.