US3811829A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Isothermal boat container
Assignee: SEMICONDUCTOR ELECT MEMORIES
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Filing: 1971-10-26
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Granted: 1974-05-21
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Expires: 1991-10-26
Abstract
Abstract In heat treating semiconductor circuits formed on wafers, the wafers are usually loaded into a boat and the boat is pushed into a diffusion furnace. This invention provides a container into which a boat is loaded and then pushed to the center of the furnace. The construction of the container is made such that the temperature gradient undergone by the semiconductor material is maintained below the value at which improper thermal stress is applied. Also, the temperature of the wafers in all locations of the boat is maintained substantially the same. As a result crystal damage is avoided.
Inventors
- 👤 R Wesson
- 👤 S Platter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 23:57
CPC Classifications
C; C30; C30B; C30B31/00; C30B31/06; C30B31/12; C30B31/10; Y; Y10; Y10S; Y10S118/00; Y10S118/90; Y10S414/00; Y10S414/135; Y10S414/14
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
92 words
In apparatus for heat treating semi-conductor wafers wherein said wafers are mounted in a boat and then pushed into a diffusion furnace for heat treatment, the improvement comprising: a container within which said boat and said semiconductor wafers are placed, said container being movable with said boat through said furnace, said container having a center opening lined with a heat conductive material, a wall around said heat conductive material comprised of a heat insulating material, and an outer coating around said wall of heat insulating material comprised of a light reflecting material.
Claim 2
Dependent Claim
92 words
In apparatus for heat treating semi-conductor wafers wherein said wafers are mounted in a boat and then pushed into a diffusion furnace for heat treatment, the improvement comprising: a container within which said boat and said semiconductor wafers are placed, said container being movable with said boat through said furnace, said container having a center opening lined with a heat conductive material, a wall around said heat conductive material comprised of a heat insulating material, and an outer coating around said wall of heat insulating material comprised of a light reflecting material.
Claim 3
Dependent Claim
24 words
Apparatus as recited in claim 1 wherein the said heat conductive material and outer coating comprise platinum and said insulating material is zirconium oxide.
Claim 4
Dependent Claim
87 words
A container for use in the heat processing of semiconductor wafers comprising: a cylinder of a heat insulating material having its thickness determined by the change of temperature with respect to time desired at the interior of said cylinder, said cylinder having an internal lining of a heat conductive material for integrating the heat which passes through said cylinder, an external surface of a light reflecting material, said semiconductor material being placed within said cylinder, and end caps for closing the open ends of said cylinder wall.
Claim 5
Dependent Claim
87 words
A container for use in the heat processing of semiconductor wafers comprising: a cylinder of a heat insulating material having its thickness determined by the change of temperature with respect to time desired at the interior of said cylinder, said cylinder having an internal lining of a heat conductive material for integrating the heat which passes through said cylinder, an external surface of a light reflecting material, said semiconductor material being placed within said cylinder, and end caps for closing the open ends of said cylinder wall.
Claim 6
Dependent Claim
24 words
A container as recited in claim 3 wherein said heat insulating material is zirconium oxide, and said internal lining and external surface comprise platinum.
Claim 7
Dependent Claim
32 words
A container as recited in claim 3 wherein said internal lining and external surface comprise platinum coatings on quartz cylinders, and said heat insulating material between said quartz cylinders comprises zirconium oxide.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-05-20 | 1977-11-19 | 1978-05-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-05-20 | 1981-11-19 | 1982-05-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-05-20 | 1985-11-19 | 1986-05-21 | $7700.00 | Window Closed / Lapsed |