US3615262A
Expired / Lapsed
US
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Crystal seed following a hypercycloid path in melt
Assignee: Siemens AG
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Filing: 1968-09-26
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Granted: 1971-10-26
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Expires: 1988-09-26
Abstract
Abstract Described is a method of producing a monocrystal rod, which is vertically held at its end, with homogeneous or almost homogeneous doping, by pulling from a crucible according to the Czochralski method. The holder of the seed crystal, which is immersed into the melt, is given an eccentric movement with respect to the melt contained in the crucible. According to the invention the holder of the seed crystal which moves along the eccentric path is given an additional movement which produces a hypercycloid path with respect to the melt.
Inventors
- 👤 Rudolf Kappelmeyer
- 👤 Max-Hugo Kellerbauer
- 👤 Karl Danassy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 06:50
CPC Classifications
C; C30; C30B; C30B15/00; C30B15/30; C30B15/305
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
25 words
The method of claim 1, wherein the maximum eccentricity of the seed crystal is approximately the magnitude of the rod diameter of the pulled crystal.
Claim 2
Dependent Claim
18 words
The method of claim 2, wherein the change of the eccentricity is approximately + or - 4 mm.
Claim 3
Dependent Claim
16 words
The method of claim 3, wherein the seed crystal is rotated at 5 to 10 r.p.m.
Claim 4
Dependent Claim
16 words
The method of claim 4, wherein the pulling velocity is 1 to 3 mm. per min.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-10-25 | 1975-04-26 | 1975-10-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-25 | 1979-04-26 | 1979-10-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-25 | 1983-04-26 | 1983-10-26 | $7700.00 | Window Closed / Lapsed |