Method for evaluating silica glass crucible, method for producing silicon single crystals
US9809902B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 31, 2012 |
| Grant date | Nov 7, 2017 |
| Priority date | — |
| Expiry date | Oct 8, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J5/58
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The present invention provides a method for evaluating a vitreous silica crucible which can measure a three-dimensional shape of the inner surface of the crucible in a non-destructive manner. According to the present invention, A method for evaluating a vitreous silica crucible, including the steps of: moving an internal ranging section along an inner surface of the vitreous silica crucible in a contactless manner; measuring a distance between the internal ranging section and the inner surface as a distance from the inner surface, by subjecting the inner surface of the crucible to irradiation with laser light and then detecting a reflected light from the inner surface, the laser light being emitted from the internal ranging section in an oblique direction with respect to the inner surface, and the measurement being conducted at a plurality of measuring points along a course of a movement of the internal ranging section; and obtaining a three-dimensional shape of the inner surface of the crucible, by associating three-dimensional coordinates of each of the measuring points with the distance from the inner surface, is provided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.