Dielectric anti-reflective coating surface treatment to prevent defect generation in associated wet clean
US7125783B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 18, 2001 |
| Grant date | Oct 24, 2006 |
| Priority date | — |
| Expiry date | Dec 31, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S438/952
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for preventing the formation of watermark defects includes the steps of forming a pad oxide, a silicon nitride layer and a silicon oxynitride layer over a semiconductor substrate. A photoresist mask is formed over the resulting structure, with the silicon oxynitride layer being used as an anti-reflective coating during exposure of the photoresist material. An etch is performed through the photoresist mask, thereby forming a trench in the substrate. The photoresist mask is stripped, and the silicon oxynitride layer is conditioned. For example, the silicon oxynitride layer may be conditioned by a rapid thermal anneal in the presence of oxygen or nitrogen. A wet clean step is subsequently performed to remove a native oxide layer in the trench. The conditioned silicon oxynitride layer prevents the formation of watermarks during the wet clean process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.