Semiconductor device having a charge transfer device, MOSFETs, and bipolar transistors--all formed in a single semiconductor substrate
US5184203A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 16, 1991 |
| Grant date | Feb 2, 1993 |
| Priority date | — |
| Expiry date | Jan 16, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D84/891
Abstract
A semiconductor device having a semiconductor substrate of a first conductivity type, an epitaxial layer of a second conductivity type formed on a major surface of the semiconductor subtrate, an isolation layer of the first conductivity type formed in the epitaxial layer and extending from a surface thereof to the major surface of the semiconductor substrate. The isolation layer divides the epitaxial layer into first, second, and third islands. The device further has two wells of the first conductivity type, formed in the first and second islands, respectively, and extending to the substrate, a charge transfer device having a back gate formed of the first well, an insulated-gate FET of the first conductivity type, having a back gate formed of the second island, an insulated-gate FET of the second conductivity type, having a back gate formed of the second well, and a bipolar transistor having a collector formed of the third island. The first island surrounds the first well which serves as back gate of the charge transfer device,and thus blocks noise generated in the first well. Hence, the other islands are free from the influence of the noise.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.