Pitcher-shaped active area for field effect transistor and method of forming same
US6960514B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 18, 2004 |
| Grant date | Nov 1, 2005 |
| Priority date | — |
| Expiry date | Apr 29, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76224
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
An improved pitcher-shaped active area for a field effect transistor that, for a given gate length, achieves an increase in transistor on-current, a decrease in transistor serial resistance, and a decrease in contact resistance. The pitcher-shaped active area structure includes at least two shallow trench insulator (STI) structures formed into a substrate that defines an active area structure, which includes a widened top portion with a larger width than a bottom portion. An improved fabrication method for forming the improved pitcher-shaped active area is also described that implements a step to form STI structure divots followed by a step to migrate substrate material into at least portions of the divots, thereby forming a widened top portion of the active area structure. The fabrication method of present invention forms the pitcher-shaped active area without the use of lithography, and therefore, is not limited by the smallest ground rules of lithography tooling.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.