Method for controlling convection pattern of silicon melt, method for producing silicon single crystals, and device for pulling silicon single crystals
US11781242B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 27, 2019 |
| Grant date | Oct 10, 2023 |
| Priority date | — |
| Expiry date | Feb 27, 2039 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC30B30/04
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A convection pattern control method includes: heating a silicon melt in a quartz crucible using a heating portion; and applying a horizontal magnetic field to the silicon melt in the quartz crucible being rotated. In the heating of the silicon, the silicon melt is heated with the heating portion whose heating capacity differs on both sides across an imaginary line passing through a center axis of the quartz crucible and being in parallel to a central magnetic field line of the horizontal magnetic field when the quartz crucible is viewed from vertically above. In the applying of the horizontal magnetic field, the horizontal magnetic field of 0.2 tesla or more is applied to fix a direction of a convection flow in a single direction in a plane orthogonal to an application direction of the horizontal magnetic field in the silicon melt.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.