Method for manufacturing a silicon ingot having uniform phosphorus concentration
US10072350B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 16, 2014 |
| Grant date | Sep 11, 2018 |
| Priority date | — |
| Expiry date | Sep 14, 2035 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC30B29/06
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A method for manufacturing a silicon ingot having uniform phosphorus concentration. The method includes at least the steps of: (i) providing a quasi-uniform molten silicon bath containing at least phosphorus; and (ii) proceeding to the directional solidification of the silicon, wherein a speed (VI) for solidifying the silicon and a rate (JLV) of evaporation of the phosphorus at the liquid/vapor interface of the bath are controlled such that, at each moment of the directional solidification, the following equation is verified: VI=k′/(2−k) (E), wherein k′ is the phosphorus transfer coefficient, and k is the distribution coefficient of the phosphorus in the silicon. Also relates to a silicon ingot having uniform phosphorus concentration across a height of at least 20 cm.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.