Dual workfunction MOSFETs with borderless diffusion contacts for high-performance embedded DRAM technology
US6335248B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 30, 2001 |
| Grant date | Jan 1, 2002 |
| Priority date | — |
| Expiry date | Apr 30, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10B12/09
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
The present invention provides a method for forming dual workfunction metal oxide semiconductor field effect transistors (MOSFETs) which utilizes processing steps that solve the problem of doping the dual work function MOSFETs, while providing contacts to the diffusion regions which are borderless to the gate conductors. Specifically, the present invention provides a method wherein a self-aligned insulating gate cap is formed on top of a previously defined and doped gate conductor region. The inventive method which forms an insulating cap that is self-aligned to an underlying gate conductor enables the formation of dual workfunction gate conductors and borderless diffusion contacts without the need of employing separate block masks as required by prior art processes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.