Depositing tungsten into high aspect ratio features
US8124531B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 28, 2011 |
| Grant date | Feb 28, 2012 |
| Priority date | — |
| Expiry date | Jan 28, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76876
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Methods and apparatuses for filling high aspect ratio features with tungsten-containing materials in a substantially void-free manner are provided. In certain embodiments, the method involves depositing an initial layer of a tungsten-containing material followed by selectively removing a portion of the initial layer to form a remaining layer, which is differentially passivated along the depth of the high-aspect ration feature. In certain embodiments, the remaining layer is more passivated near the feature opening than inside the feature. The method may proceed with depositing an additional layer of the same or other material over the remaining layer. The deposition rate during this later deposition operation is slower near the feature opening than inside the features due to the differential passivation of the remaining layer. This deposition variation, in turn, may aid in preventing premature closing of the feature and facilitate filling of the feature in a substantially void free manner.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.