Patent US1083757A successfully refreshed from Google Patents.
Patent US5306388A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5306388A Expired / Lapsed US ⏱️ 0.0 years remaining

Quartz glass crucible for pulling a semiconductor single crystal

Assignee: Coorstek KK
•
Filing: 1992-01-31
•
Granted: 1994-04-26
•
Expires: 2012-01-31
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A quartz glass crucible for pulling a single crystal, which comprises a cylindrical straight wall portion, a bottom wall portion and a curved intermediate wall portion connecting the straight portion and the bottom portion. The straight portion has an opaque area positioned within about 75% or less of the total height of the crucible, measured from the upper open end of the crucible. The opaque area in the straight portion has a total bubble volume which ranges from about 7*10-3 cm3/cm3 to 30*10-3 cm3/cm3. The remaining straight portion, the curved intermediate portion and the bottom portion consist of transparent material having a total volume of bubbles of about 4*10-3 cm3/cm3 or less.

Inventors

  • 👤 Toshio Nakajima
  • 👤 Tohru Ito
  • 👤 Yoshinobu Nagamine

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 02:18
CPC Classifications
C; C30; C30B; C30B15/00; C30B15/10; C03; C03B; C03B19/00; C03B19/09; C03B19/095; Y; Y02; Y02P; Y02P40/00; Y02P40/50; Y02P40/57; Y10; Y10S; Y10S117/00; Y10S117/90; Y10T; Y10T117/00; Y10T117/10; Y10T117/1024; Y10T117/1032

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 145 words
A quartz glass crucible for pulling a semiconductor single crystal, which comprises: a cylindrical straight wall portion comprising a first area and a second area, said first area having a height corresponding to about 75% or less of the total height of the crucible measured from an upper open end of the crucible, the first area comprising across its entire thickness an opaque material having a volume of bubbles ranging from about 7×10 -3 cm 3 /cm 3 to 30×10 -3 cm 3 /cm 3 ; a bottom wall portion; and a curved intermediate wall portion connecting the straight wall portion and the bottom-wall portion; the second area of the straight wall portion, the bottom wall portion and the curved intermediate wall portion consist essentially of transparent quartz glass having a total volume of bubbles of about 4×10 -3 cm 3 /cm 3 or less.
Claim 2
Dependent Claim 145 words
A quartz glass crucible for pulling a semiconductor single crystal, which comprises: a cylindrical straight wall portion comprising a first area and a second area, said first area having a height corresponding to about 75% or less of the total height of the crucible measured from an upper open end of the crucible, the first area comprising across its entire thickness an opaque material having a volume of bubbles ranging from about 7×10 -3 cm 3 /cm 3 to 30×10 -3 cm 3 /cm 3 ; a bottom wall portion; and a curved intermediate wall portion connecting the straight wall portion and the bottom-wall portion; the second area of the straight wall portion, the bottom wall portion and the curved intermediate wall portion consist essentially of transparent quartz glass having a total volume of bubbles of about 4×10 -3 cm 3 /cm 3 or less.
Claim 3
Dependent Claim 36 words
A quartz glass crucible for pulling a semiconductor single crystal as defined in claim 1, in which the first area of the straight wall portion is integral with the second area of the straight wall portion.
Claim 4
Dependent Claim 56 words
A quartz glass crucible for pulling a semiconductor single crystal as defined claim 1, in which the second area of the straight wall portion, the bottom wall portion and the curved intermediate wall portion consist essentially of transparent quartz glass having a total volume of bubbles of about 1×10 -3 cm 3 /cm 3 or less.
Claim 5
Dependent Claim 67 words
A quartz glass crucible for pulling a semiconductor single crystal as defined in claim 1, in which the straight wall portion further comprises a third area disposed between the first area and the second area, the third area having a total volume of bubbles greater than the total volume of bubbles of the second area and smaller than the total volume of bubbles of the first area.
Claim 6
Independent Claim 189 words
An apparatus for pulling silicon single crystal comprising: a quartz glass crucible comprising: a cylindrical straight wall portion comprising a first area and a second area, said first area having a height corresponding to about 75% or less of the total height of the crucible measured from an upper open end of the crucible, the first area comprising across its entire thickness an opaque material having a volume of bubbles ranging from about 7×10 -3 cm 3 /cm 3 to 30×10 -3 cm 3 /cm 3 ; a bottom wall portion; and a curved intermediate wall portion connecting the straight wall portion and the bottom wall portion; the second area of the straight wall portion, the bottom wall portion and the curved intermediate wall portion consist essentially of transparent quartz glass having a total volume of bubbles of about 4×10 -3 cm 3 /cm 3 or less; a holder contacting the quartz glass crucible for holding the crucible; a heater surrounding the quartz glass crucible and the holder; and a chamber in which the quartz glass crucible is provided, the chamber being able to provide an airtight internal space.
Claim 7
Independent Claim 189 words
An apparatus for pulling silicon single crystal comprising: a quartz glass crucible comprising: a cylindrical straight wall portion comprising a first area and a second area, said first area having a height corresponding to about 75% or less of the total height of the crucible measured from an upper open end of the crucible, the first area comprising across its entire thickness an opaque material having a volume of bubbles ranging from about 7×10 -3 cm 3 /cm 3 to 30×10 -3 cm 3 /cm 3 ; a bottom wall portion; and a curved intermediate wall portion connecting the straight wall portion and the bottom wall portion; the second area of the straight wall portion, the bottom wall portion and the curved intermediate wall portion consist essentially of transparent quartz glass having a total volume of bubbles of about 4×10 -3 cm 3 /cm 3 or less; a holder contacting the quartz glass crucible for holding the crucible; a heater surrounding the quartz glass crucible and the holder; and a chamber in which the quartz glass crucible is provided, the chamber being able to provide an airtight internal space.
Claim 8
Dependent Claim 26 words
An apparatus as defined in claim 5, in which said second area of the straight portion is integral with the first area of the straight portion.
Claim 9
Dependent Claim 49 words
An apparatus as defined in claim 5, in which the second area of the straight wall portion, the bottom wall portion and the curved intermediate wall portion consist essentially of transparent quartz glass having a total volume of bubbles of about 1×10 -3 cm 3 /cm 3 or less.
Claim 10
Dependent Claim 59 words
An apparatus as defined in claim 5, in which the straight wall portion further comprises a third area disposed between the first area and the second area, the third area having a total volume of bubbles greater than the total volume of bubbles of the second area and smaller than the total volume of bubbles of the first area.
Claim 11
Independent Claim 171 words
A method of pulling a silicon single crystal comprising the steps of: supplying metallic silicon into a quartz crucible comprising: a cylindrical straight wall portion comprising a first area and a second are, said first area having a height corresponding to about 75% or less of the total height of the crucible measured from an upper open end of the crucible, the first area comprising across its entire thickness an opaque material having a volume of bubbles ranging from about 7×10 -3 cm 3 /cm 3 to 30×10 -3 cm 3 /cm 3 ; a bottom wall portion; and a curved intermediate wall portion connecting the straight wall portion and the bottom wall portion; the second area of the straight wall portion, the bottom wall portion and the curved intermediate wall portion consist essentially of transparent quartz glass having a total volume of bubbles of about 4×10 -3 cm 3 /cm 3 or less; melting the metallic silicon by heating; and pulling a silicon single crystal from the melted metallic silicon.
Claim 12
Independent Claim 171 words
A method of pulling a silicon single crystal comprising the steps of: supplying metallic silicon into a quartz crucible comprising: a cylindrical straight wall portion comprising a first area and a second are, said first area having a height corresponding to about 75% or less of the total height of the crucible measured from an upper open end of the crucible, the first area comprising across its entire thickness an opaque material having a volume of bubbles ranging from about 7×10 -3 cm 3 /cm 3 to 30×10 -3 cm 3 /cm 3 ; a bottom wall portion; and a curved intermediate wall portion connecting the straight wall portion and the bottom wall portion; the second area of the straight wall portion, the bottom wall portion and the curved intermediate wall portion consist essentially of transparent quartz glass having a total volume of bubbles of about 4×10 -3 cm 3 /cm 3 or less; melting the metallic silicon by heating; and pulling a silicon single crystal from the melted metallic silicon.

References Cited (Backward Citations)

US4528163A Cited
US4416680A Cited
US4632686A Cited
US4935046A Cited
US4956208A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-04-25 1997-10-25 1998-04-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-04-25 2001-10-25 2002-04-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-04-25 2005-10-25 2006-04-26 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag