Nitride removal while protecting semiconductor surfaces for forming shallow junctions
US8043921B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 25, 2010 |
| Grant date | Oct 25, 2011 |
| Priority date | — |
| Expiry date | Mar 25, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D64/021
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method of removing silicon nitride over a semiconductor surface for forming shallow junctions. Sidewall spacers are formed along sidewalls of a gate stack that together define lightly doped drain (LDD) regions or source/drain (S/D) regions. At least one of the sidewall spacers, LDD regions and S/D regions include an exposed silicon nitride layer. The LDD or S/D regions include a protective dielectric layer formed directly on the semiconductor surface. Ion implanting implants the LDD regions or S/D regions using the sidewall spacers as implant masks. The exposed silicon nitride layer is selectively removed, wherein the protective dielectric layer when the sidewall spacers include the exposed silicon nitride layer, or a replacement protective dielectric layer formed directly on the semiconductor surface after ion implanting when the LDD or S/D regions include the exposed silicon nitride layer, protects the LDD or S/D regions from dopant loss due to etching during selectively removing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.