Method for forming a conductive plug between conductive layers of an integrated circuit
US6372638B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 22, 2000 |
| Grant date | Apr 16, 2002 |
| Priority date | — |
| Expiry date | Jun 22, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76877
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for forming void free tungsten plug contacts (56a-56c) begins by etching a contact opening (55a-55c) using a C2F6 and CHF3 chemistry. The etch chemistry is then changed to an O2 and CH3F chemistry in order to insitu remove the contact photoresist while tapering an upper portion of the contact opening. A tungsten deposition process is then performed whereby the tapered portion of the contact reduces the effects of nonconformal and step-coverage-inconsistent tungsten deposition wherein voids in the contact are either substantially reduced or totally avoided within the contact structure. The reduction of or total elimination of voids (22) within the tungsten contact will increase yield, increase reliability, and reduce electromigration failures within integrated circuit devices.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.