Protruding spacers for self-aligned contacts
US7126198B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 3, 2002 |
| Grant date | Oct 24, 2006 |
| Priority date | — |
| Expiry date | Sep 3, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A protruding spacer that protrudes above the top surface of a gate electrode structure provides enhanced resistance to exposure of the gate electrode during the etch process used to form self-aligned contacts. The protruding spacer may be formed using an amorphous carbon sacrificial layer as the top layer of the patterned gate electrode structure. Dielectric spacers are formed alongside the gate electrode structure, including alongside the sacrificial amorphous carbon layer. The dielectric spacers extend substantially to the top of the amorphous carbon layer. The amorphous carbon layer is then removed such that the remaining gate structure includes dielectric spacers that have a protruding section that protrudes above the top surface of the remaining gate structure. A nitride layer may be formed over the gate structure. Such a structure prevents exposure of the gate electrode during the formation of self-aligned contacts, and shorting, once the contact openings are filled.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.