Method for manufacturing semiconductor integrated circuit device
US7687849B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 29, 2008 |
| Grant date | Mar 30, 2010 |
| Priority date | — |
| Expiry date | May 29, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10B12/315
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Disclosed is a technique for reducing the leak current by reducing contamination of metal composing a polymetal gate of a MISFET. Of a polycrystalline silicon film, a WN film, a W film, and a cap insulating film formed on a gate insulating film on a p-type well (semiconductor substrate), the cap insulating film, the W film, and the WN film are etched and the over-etching of the polycrystalline silicon film below them is performed. Then, a sidewall film is formed on sidewalls of these films. Thereafter, after etching the polycrystalline silicon film with using the sidewall film as a mask, a thermal treatment is performed in an oxidation atmosphere, by which a light oxide film is formed on the sidewall of the polycrystalline silicon film. As a result, the contamination on the gate insulating film due to the W and the W oxide can be reduced, and also, the diffusion of these materials into the semiconductor substrate (p-type well) and the resultant increase of the leak current can be prevented.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.