Solidification of crystalline silicon from reusable crucible molds
US7540919B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 31, 2006 |
| Grant date | Jun 2, 2009 |
| Priority date | — |
| Expiry date | Aug 11, 2027 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2495
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A process for making silicon ingots using a multi-part, reusable, graphite crucible of at least two mold pieces configured for assembly into an open top mold having an interior surface functional as a mold cavity for receiving molten silicon; removing or reducing a prior applied release coating from the interior surface until a uniformly smooth finish is achieved; coating the interior surface with a first layer of release coating comprising silicon nitride; coating the interior surface with a second layer of release coat comprising silica suspended in water; coating the interior surface with a third layer of release coat comprising silicon nitride; curing the release coat on said crucible; casting a silicon ingot in the crucible; and then repeating the prior steps multiple times.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.