Method for forming contact plug
US6225214A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 14, 1999 |
| Grant date | May 1, 2001 |
| Priority date | — |
| Expiry date | Sep 14, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76877
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for forming a contact plug. A substrate having a dielectric layer thereon is provided. The dielectric layer has an opening that exposes a thin layer of native oxide. A first and a second conformal doped polysilicon layer are formed over the opening. The first doped polysilicon layer has a dopant concentration greater than that of the second doped polysilicon layer. A third doped polysilicon layer that also fills the opening is formed over second doped polysilicon layer. Dopant concentration of the third doped polysilicon layer is smaller than the second doped polysilicon layer. Last, the first, the second and the third doped polysilicon layer are annealed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.