Method of eliminating buried contact resistance in integrated circuits
US6008125A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 12, 1997 |
| Grant date | Dec 28, 1999 |
| Priority date | — |
| Expiry date | Dec 12, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76895
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method is disclosed for forming a buried contact within an integrated circuit ("IC"). Initially, a gate oxide layer is deposited onto a surface of a silicon substrate. A first polysilicon layer is deposited onto the gate oxide layer using an ionized cluster beam ("ICB") technique. The first polysilicon layer and the gate oxide layer are patterned and etched at predetermined locations, exposing the underlying silicon substrate surface at these locations. A small amount of undesirable native oxide grows on the exposed substrate surface. This oxide represents an unwanted impedance, which degrades IC device performance. The ICB machine is then used to deposit a second layer of polysilicon on the silicon substrate, including over the oxide layer regions and over the exposed silicon substrate surface at the predetermined locations. This second polysilicon deposition step breaks up and removes the unwanted native oxide from the silicon substrate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.