Title:
METHOD FOR MEASURING TEMPERATURE OF SURFACE OF SINGLE CRYSTAL
Document Type and Number:
Japanese Patent JP3628823
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To simply and correctly detect a surface temperature of a single crystal by obtaining a luminance temperature distribution of a bright ring appearing at a boundary part of a single crystal rod and a molten liquid, and subtracting a disturbing light reflection component obtained from a maximum radiance.
SOLUTION: A luminance of an observation range 16 of a bright ring 13 appearing at a boundary part of a single crystal rod grown in a Chochralski furnace and a molten liquid 12 is observed in an arrow direction (a Y-axis direction) by a two-dimensional CCD infrared camera preferably having a sensitivity to near infrared rays of a wavelength band 700-1100nm. A temperature obtained according to a luminance- temperature conversion formula and a solidifying point temperature of the single crystal (a maximum radiance of the bright ring 13) are compared, and a difference of the temperatures is set as a reflection component by a disturbing light. Supposing that the reflection component is also impressed to a high emissivity part (window part) 15 above the bright ring 13, a correct temperature of the window part 15 is obtained from a luminance from which the reflection component is subtracted. The calculation is carried out to the whole of the window part 15. A temperature distribution is thus obtained and a temperature gradient along the Y axis can be calculated.
Inventors:
Etsuro Suganuma
Application Number:
JP31879196A
Publication Date:
March 16, 2005
Filing Date:
November 14, 1996
Export Citation:
Assignee:
Tokai Carbon Co., Ltd.
International Classes:
G01J5/10; G01J5/00; G01J5/48; (IPC1-7): G01J5/48; G01J5/00
Domestic Patent References:
| JP8239293A | ||||
| JP8259381A | ||||
| JP8301689A | ||||
| JP7243911A |
Attorney, Agent or Firm:
Yasuo Fukuda
Kenji Akatsuka
Kenji Akatsuka