Methods of forming electrical contacts
US6281131A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 27, 1998 |
| Grant date | Aug 28, 2001 |
| Priority date | — |
| Expiry date | Feb 27, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S438/953
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method of forming an electrical contact to semiconductive material includes forming an insulative layer over a contact area of semiconductive material. A contact opening is etched through the insulative layer to the semiconductive material contact area. Such etching changes an outer portion of the semiconductive material exposed by the etching. The change is typically in the form of modifying crystalline structure of only an outer portion from that existing prior to the etch. The changed outer portion of the semiconductive material is etched substantially selective relative to semiconductive material therebeneath which is unchanged. The preferred etching chemistry is a tetramethyl ammonium hydroxide solution. A conductive material within the contact opening is formed in electrical connection with the semiconductive material. In another aspect, the changed outer portion is etched with a basic solution regardless of selectivity in the etch relative to semiconductive material therebeneath which is unchanged by the contact opening etch. The preferred conductive material is conductively doped semiconductive material which is formed in the contact opening to be in contact with semicond…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.