Method for avoiding photo residue in dual damascene with acid treatment
US6417096B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 7, 2000 |
| Grant date | Jul 9, 2002 |
| Priority date | — |
| Expiry date | Jul 7, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76807
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A substrate is provided. A first dielectric layer is formed over the substrate by deposition. Etching stop layer and a second dielectric layer are formed in turn over the first dielectric. Next, the second dielectric layer is dealt with Lewis acid. Then, a first photoresist layer is defined and formed over the second dielectric layer. And then dry etching is carried out by means of the first photoresist layer as the mask to form a via hole. The surface of the second dielectric layer and the via hole are treated with Lewis acid. Subsequently, the second photoresist layer is defined and formed on the second dielectric layer. Dry etching is proceed, and etching stop layer is as a etching terminal point to remove exposed partial surface of the second dielectric layer so as to form a trench having larger horizontal size than the via hole. Subsequently, the second photoresist layer is removed to form the opening of the damascene.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.