Process for forming uniform multiple contact holes
US6458710B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 9, 2001 |
| Grant date | Oct 1, 2002 |
| Priority date | — |
| Expiry date | Apr 9, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A process for defining uniform contact hole openings in an insulator layer, and in a top portion of a conductive layer, has been developed. The process features a series of isotropic and anisotropic, dry etch procedures, used to define an initial contact hole opening in the insulator layer, and in the top portion of the conductive region. The isotropic dry etch procedure results in a tapered contact hole profile for top portion of the initial contact hole opening, while subsequent anisotropic dry etch procedures create a straight walled contact hole profile for the bottom portion of the initial contact hole opening. After removal of the contact hole defining, photoresist shape, a wet etch procedure is used to laterally recess-the insulator layer exposed in the initial contact hole opening creating the final, uniform contact hole opening.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.