Method of forming a tungsten plug
US6140224A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 19, 1999 |
| Grant date | Oct 31, 2000 |
| Priority date | — |
| Expiry date | Apr 19, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76835
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A dielectric layer and a polishing stop layer are respectively formed over a substrate. A glue layer composed of titanium (Ti) is formed along the surface of the dielectric layer. The Ti layer serves as adhension promotion to the subsequent TiN layer. A titanium-nitride (TiN) layer is next formed on the Ti layer to act as a barrier layer. A tungsten layer is deposited on the TiN layer. An etching back step is carried to etch the tungsten layer, therby leaving the tungsten in the contact holes to form the tungsten plug. Non-metal or oxide CMP is used to removes tungsten residues and TiN/Ti layers and the CMP will stop on the polishing stop layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.