Patent US4404172A successfully refreshed from Google Patents.
US4404172A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for forming and growing a single crystal of a semiconductor compound
Assignee: AT&T Inc
•
Filing: 1981-01-05
•
Granted: 1983-09-13
•
Expires: 2001-01-05
Abstract
Abstract An apparatus 10 for growing single crystal semiconductor compounds by the gradient freeze method includes means 40 for reducing radiant heat flow while enhancing axial heat flow in the region of a seed crystal 39 so as to give rise to an inverted solid-liquid interface shape 36 and a desired temperature profile.
Inventors
- 👤 William A. Gault
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:47
CPC Classifications
C; C30; C30B; C30B11/00; C30B11/003; Y; Y10; Y10S; Y10S117/00; Y10S117/90; Y10T; Y10T117/00; Y10T117/10; Y10T117/1024; Y10T117/1092
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
147 words
An apparatus for growing a single crystal of a Group II-VI or III-V semiconductor compound by the gradient zone freeze method including: (a) an autoclave having contained therein: (i) a chamber provided with heating means for containing and volatilizing the volatile component of the compound to be grown: (ii) a growth crucible communicating with the chamber so that an atmosphere of said volatile component is provided in the growth crucible during crystal growth and having a lower seed well region for containing a seed crystal and a transition region and main growth region extending therefrom for containing charge material of the compound; and (iii) support means for supporting said crucible, said support means having a configuration so as to cause reduction of radial heat flow and an enhancement of axial heat flow at least around the seed well and transition regions of said crucible during crystal growth.
Claim 2
Independent Claim
147 words
An apparatus for growing a single crystal of a Group II-VI or III-V semiconductor compound by the gradient zone freeze method including: (a) an autoclave having contained therein: (i) a chamber provided with heating means for containing and volatilizing the volatile component of the compound to be grown: (ii) a growth crucible communicating with the chamber so that an atmosphere of said volatile component is provided in the growth crucible during crystal growth and having a lower seed well region for containing a seed crystal and a transition region and main growth region extending therefrom for containing charge material of the compound; and (iii) support means for supporting said crucible, said support means having a configuration so as to cause reduction of radial heat flow and an enhancement of axial heat flow at least around the seed well and transition regions of said crucible during crystal growth.
Claim 3
Dependent Claim
24 words
The apparatus recited in claim 1 wherein said seed well is a narrow elongated member extending from the bottom of a conical transition region.
Claim 4
Dependent Claim
25 words
The apparatus recited in claim 1 wherein said support means comprises at least one vertical slot extending parallel to the axis of the growth crucible.
Claim 5
Dependent Claim
17 words
The apparatus recited in claim 6 wherein said support means is comprised of graphite or boron nitride.
Claim 6
Independent Claim
138 words
An apparatus for growing a single crystal of a Group II-VI or III-V semiconductor compound by the gradient zone freeze method including: (a) an autoclave having contained therein: (i) a chamber provided with heating means for containing and volatilizing the volatile component of the compound to be grown: (ii) a growth crucible communicating with the chamber so that an atmosphere of said volatile component is provided in the growth crucible during crystal growth and having a lower seed well region for containing a seed crystal, a transition region extending from the seed well, and a main growth region extending from the top of the transition region; and (iii) means associated with the growth crucible for causing an inversion or flattening of the normally occurring meniscus at the liquid-solid interface at least during the initial period of crystal growth.
Claim 7
Independent Claim
138 words
An apparatus for growing a single crystal of a Group II-VI or III-V semiconductor compound by the gradient zone freeze method including: (a) an autoclave having contained therein: (i) a chamber provided with heating means for containing and volatilizing the volatile component of the compound to be grown: (ii) a growth crucible communicating with the chamber so that an atmosphere of said volatile component is provided in the growth crucible during crystal growth and having a lower seed well region for containing a seed crystal, a transition region extending from the seed well, and a main growth region extending from the top of the transition region; and (iii) means associated with the growth crucible for causing an inversion or flattening of the normally occurring meniscus at the liquid-solid interface at least during the initial period of crystal growth.
Claim 8
Independent Claim
159 words
An apparatus for growing a single crystal of a semiconductor compound by the gradient zone freeze method including: (a) a growth crucible having a lower seed well region for containing a seed crystal and a transition region and main growth region extending therefrom for containing charge material of the compound; and (b) support means for supporting said crucible, said support means having a configuration so as to cause reduction of radial heat flow and an enhancement of axial heat flow at least around the seed well and transition regions of said crucible during crystal growth, and wherein said seed well is a narrow elongated member positioned in a hole provided therefor in said support means and wherein said support means includes a plurality of vertical slots extending parallel to the axis of the growth crucible, said vertical slots extending from the top surface of said support means to a depth substantially adjacent to the bottom of said seed well.
Claim 9
Independent Claim
159 words
An apparatus for growing a single crystal of a semiconductor compound by the gradient zone freeze method including: (a) a growth crucible having a lower seed well region for containing a seed crystal and a transition region and main growth region extending therefrom for containing charge material of the compound; and (b) support means for supporting said crucible, said support means having a configuration so as to cause reduction of radial heat flow and an enhancement of axial heat flow at least around the seed well and transition regions of said crucible during crystal growth, and wherein said seed well is a narrow elongated member positioned in a hole provided therefor in said support means and wherein said support means includes a plurality of vertical slots extending parallel to the axis of the growth crucible, said vertical slots extending from the top surface of said support means to a depth substantially adjacent to the bottom of said seed well.
Claim 10
Independent Claim
116 words
An apparatus for growing a single crystal of a semiconductor compound by the gradient zone freeze method including: (a) a growth crucible having a lower seed well region for containing a seed crystal, a transition region extending from the seed well, and a main growth region extending from the top of the transition region; and (b) means associated with the growth crucible for causing an inversion or flattening of the normally occurring meniscus at the liquid-solid interface at least during the initial period of crystal growth comprising a support member which supports said crucible at said transition region and which is provided with a plurality of concentric axially extending slots extending downwardly from its supporting surface.
Claim 11
Independent Claim
116 words
An apparatus for growing a single crystal of a semiconductor compound by the gradient zone freeze method including: (a) a growth crucible having a lower seed well region for containing a seed crystal, a transition region extending from the seed well, and a main growth region extending from the top of the transition region; and (b) means associated with the growth crucible for causing an inversion or flattening of the normally occurring meniscus at the liquid-solid interface at least during the initial period of crystal growth comprising a support member which supports said crucible at said transition region and which is provided with a plurality of concentric axially extending slots extending downwardly from its supporting surface.
References Cited (Backward Citations)
US2768277A
Cited
US1279146A
Cited
US3273969A
Cited
US3393054A
Cited
US3514265A
Cited
US3759310A
Cited
US4157373A
Cited
US3857436A
Cited
US3972689A
Cited
US4242307A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-09-12 | 1987-03-14 | 1987-09-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-09-12 | 1991-03-14 | 1991-09-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-09-12 | 1995-03-14 | 1995-09-13 | $7700.00 | Window Closed / Lapsed |