Method of filling trenches using vapor-liquid-solid mechanism
US6605535B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 26, 2002 |
| Grant date | Aug 12, 2003 |
| Priority date | — |
| Expiry date | Sep 26, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S977/844
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A method of filling trenches such as a DT cell with silicon is described that involves a vapor-liquid-solid (VLS) mechanism. First, a thin film of Si is grown on the trench sidewalls. Seed metal such as Au, Ni or Ni alloy is deposited on the sidewalls by an electroless plating process. A thermal treatment is then used to reflow the metal to a liquid state art the trench bottom. A Si precursor gas is applied to grow a single whisker that fills the trench. Silicon overgrowth is removed by an etch or CMP step. The method can also be applied to filling a via hole with silicide. In this case the seed metal is Ti, Co, or Ni which is reflowed by a thermal treatment. A silicon source gas like SiCl4 is combined with H2 to grow the silicide layer. This method is especially useful in forming seamless fill layers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.