Methods for improving uniformity and resistivity of thin tungsten films
US8101521B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 11, 2009 |
| Grant date | Jan 24, 2012 |
| Priority date | — |
| Expiry date | Dec 11, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
The methods described herein relate to deposition of low resistivity, highly conformal tungsten nucleation layers. These layers serve as a seed layers for the deposition of a tungsten bulk layer. The methods are particularly useful for tungsten plug fill in which tungsten is deposited in high aspect ratio features. The methods involve depositing a nucleation layer by a combined PNL and CVD process. The substrate is first exposed to one or more cycles of sequential pulses of a reducing agent and a tungsten precursor in a PNL process. The nucleation layer is then completed by simultaneous exposure of the substrate to a reducing agent and tungsten precursor in a chemical vapor deposition process. In certain embodiments, the process is performed without the use of a borane as a reducing agent.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.