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US4596700A Expired / Lapsed US ⏱️ 0.0 years remaining

Apparatus for producing single crystal

Assignee: Sumitomo Electric Industries Ltd
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Filing: 1984-11-13
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Granted: 1986-06-24
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Expires: 2004-11-13
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Abstract

Abstract An apparatus for producing a single crystal according to the CZ method, which comprises a closed container consisting of upper and lower halves and having a shaft for pulling up the single crystal, at least a part of which contacting with said vapor of the elements is made of a material containing an element of the same group of the periodic table as that of component elements of the single crystal, a gap between said shaft and the container and an opening between said upper and lower halves of the container being sealed with a sealing material, at least one reservoir positioned in the container for supplying vapor of a volatile component element of the single crystal, and a heating means provided around the container; wherein a hot zone of the apparatus including the container is made of a material which has an X-ray absorption coefficient not larger than 5 cm 2 /g, and said material of the hot zone has such thickness that X-ray transmittance through the whole hot zone is 10 -6 or more so as to monitor the single crystal being pulled up by X-ray fluoroscopy.

Inventors

  • 👤 Kohji Tada
  • 👤 Kotani Toshihiro
  • 👤 Masahiro Nakagawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 16:58
CPC Classifications
C; C30; C30B; C30B15/00; C30B15/10; C30B15/20; C30B15/22; C30B15/26; Y; Y10; Y10S; Y10S117/00; Y10S117/90; Y10T; Y10T117/00; Y10T117/10; Y10T117/1004; Y10T117/1012; Y10T117/1024; Y10T117/1032; Y10T117/106; Y10T117/1064

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 215 words
An apparatus for producing a single crystal according to the CZ method, which comprises a closed container consisting of upper and lower halves and having a shaft for pulling up the single crystal, in which a single crystal growing portion is provided and a vaporous atmosphere of a volatile element of the crystal is contained, at least that part of said container which contacts said vapor of the elements being made of a material containing an element of the same group of the periodic table as that of component elements of the single crystal, a gap between said shaft and the container and an opening between said upper and lower halves of the container being sealed with B 2 O 3 melt, at least one reservoir positioned in the container for supplying vapor of a volatile component element of the single crystal, and a heating means provided around the container; wherein a hot zone of the apparatus including the container is made of a material which has an X-ray mass absorption coefficient not larger than 5 cm 2 /g, and said material of the hot zone has such thickness that X-ray transmittance through the whole hot zone is 10 -6 or more so as to monitor the single crystal being pulled up by X-ray fluoroscopy.
Claim 2
Independent Claim 215 words
An apparatus for producing a single crystal according to the CZ method, which comprises a closed container consisting of upper and lower halves and having a shaft for pulling up the single crystal, in which a single crystal growing portion is provided and a vaporous atmosphere of a volatile element of the crystal is contained, at least that part of said container which contacts said vapor of the elements being made of a material containing an element of the same group of the periodic table as that of component elements of the single crystal, a gap between said shaft and the container and an opening between said upper and lower halves of the container being sealed with B 2 O 3 melt, at least one reservoir positioned in the container for supplying vapor of a volatile component element of the single crystal, and a heating means provided around the container; wherein a hot zone of the apparatus including the container is made of a material which has an X-ray mass absorption coefficient not larger than 5 cm 2 /g, and said material of the hot zone has such thickness that X-ray transmittance through the whole hot zone is 10 -6 or more so as to monitor the single crystal being pulled up by X-ray fluoroscopy.
Claim 3
Dependent Claim 51 words
An apparatus according to claim 1, wherein a part of the container is made of a material selected from the group consisting of boron nitride, pyrolytic boron nitride, aluminum nitride, graphite and quartz coated with a material selected from the group consisting of boron nitride, pyrolytic boron nitride and aluminum nitride.
Claim 4
Dependent Claim 16 words
An apparatus according to claim 1, which is used for producing a single crystal of GaAs.
Claim 5
Dependent Claim 43 words
An apparatus according to claim 1 wherein the inner portion of said container which contacts said vapor is made of a material containing an element of the same group of the periodic table as that of the component elements of the single crystal.

References Cited (Backward Citations)

CA729096A Cited
US3499736A Cited
US3627499A Cited
US3716345A Cited
US3857679A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-06-23 1989-12-23 1990-06-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-06-23 1993-12-23 1994-06-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-06-23 1997-12-23 1998-06-24 $7700.00 Window Closed / Lapsed

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