System and method for providing a dry-wet-dry etch procedure to create a sidewall profile of a via
US7115500B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 4, 2004 |
| Grant date | Oct 3, 2006 |
| Priority date | — |
| Expiry date | Oct 4, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/31116
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A system and method is disclosed for providing a dry-wet-dry etch procedure to create a sidewall profile of a via in a semiconductor device. A first vertical anisotropic dry etch process is applied to etch through a first portion of a dielectric layer. An isotropic wet etch process is then applied to etch a sloping surface in the sidewalls of the via cavity. A second vertical anisotropic dry etch process is then applied to extend the sloping sidewalls of the via cavity down to a substrate of the semiconductor device. The smooth sloping surfaces of the sidewalls are formed without a prior art concave surface of the type that interferes with a via fill process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.