Methods for depositing ultra thin low resistivity tungsten film for small critical dimension contacts and interconnects
US8623733B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 6, 2010 |
| Grant date | Jan 7, 2014 |
| Priority date | — |
| Expiry date | Aug 20, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Provided are methods of void-free tungsten fill of high aspect ratio features. According to various embodiments, the methods involve a reduced temperature chemical vapor deposition (CVD) process to fill the features with tungsten. In certain embodiments, the process temperature is maintained at less than about 350° C. during the chemical vapor deposition to fill the feature. The reduced-temperature CVD tungsten fill provides improved tungsten fill in high aspect ratio features, provides improved barriers to fluorine migration into underlying layers, while achieving similar thin film resistivity as standard CVD fill. Also provided are methods of depositing thin tungsten films having low-resistivity. According to various embodiments, the methods involve performing a reduced temperature low resistivity treatment on a deposited nucleation layer prior to depositing a tungsten bulk layer and/or depositing a bulk layer via a reduced temperature CVD process followed by a high temperature CVD process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.