US4258009A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Large crystal float zone apparatus
Assignee: Topsil GlobalWafers AS
•
Filing: 1978-05-08
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Granted: 1981-03-24
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Expires: 1998-05-08
Abstract
Abstract Apparatus for the float zone refining of large semiconductor crystals. Additional support in the form of lightweight pins is provided for the growing monocrystalline rod to hold the rod on the proper vertical axis. The pins protrude from the telescoping inner wall portion of the refining enclosure. This telescoping enclosure portion allows the pins to be in synchronous motion with the monocrystalline rod and also reduces the overall height of the apparatus.
Inventors
- 👤 Noel De Leon
- 👤 Arno I. M. Larsen
- 👤 Poul E. Knudsen
- 👤 Erik H. Jensen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 03:12
CPC Classifications
C; C30; C30B; C30B13/00; C30B13/28; C30B13/285; Y; Y10; Y10S; Y10S117/00; Y10S117/90; Y10S117/911; Y10T; Y10T117/00; Y10T117/10; Y10T117/1024; Y10T117/1076; Y10T117/1084
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
80 words
In an apparatus for the float zone refining of semiconductor materials which comprises a refining enclosure within which a rod of said semiconductor material is held and within which a molten zone traverses the length of said rod of semiconductor material and resolidifies forming a refined portion the improvement which comprises: a telescoping lower portion of said enclosure, and pins extensible from said lower portion and at an acute angle therewith for supporting the refined portion of said semiconductor rod.
Claim 2
Dependent Claim
80 words
In an apparatus for the float zone refining of semiconductor materials which comprises a refining enclosure within which a rod of said semiconductor material is held and within which a molten zone traverses the length of said rod of semiconductor material and resolidifies forming a refined portion the improvement which comprises: a telescoping lower portion of said enclosure, and pins extensible from said lower portion and at an acute angle therewith for supporting the refined portion of said semiconductor rod.
Claim 3
Dependent Claim
20 words
The apparatus of claim 1 wherein said pins can be made to protrude from said wall at a prescribed time.
Claim 4
Dependent Claim
14 words
The apparatus of claim 1 wherein said pins are hollow and fabricated of titanium.
Claim 5
Dependent Claim
25 words
The apparatus of claim 1 wherein at least a part of said telescoping portion is rotating synchronously with said refined portion of said semiconductor rod.
Claim 6
Dependent Claim
16 words
The apparatus of claim 5 further comprising means for holding said telescoping portion initially vertically stationary.
Claim 7
Dependent Claim
33 words
The apparatus of claim 5 wherein said means for holding said telescoping portion can also be set in vertical motion to enlarge said refining enclosure and to provide vertical motion to said pins.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-03-23 | 1984-09-22 | 1985-03-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-23 | 1988-09-22 | 1989-03-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-23 | 1992-09-22 | 1993-03-24 | $7700.00 | Window Closed / Lapsed |