Patent US4699084A successfully refreshed from Google Patents.
US4699084A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for producing high quality epitaxially grown semiconductors
Assignee: United States Department of the Army
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Filing: 1982-12-23
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Granted: 1987-10-13
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Expires: 2002-12-23
Abstract
Abstract A high pressure furnace and reusable demountable containment means for setive in situ information of epitaxial layers on a semiconductor substrate while under gas overpressure. The containment means has vent means therein for allowing the inert and reducing or reactive gases in an inner chamber of the furnace to enter into the interior of the containment means to equalize pressures on each side of the housing and to semi-confine the vapor from the epitaxial growth source materials in the interior of the containment means. The containment means has a removable, i.e. demountable, form-fittedly sealed plug which is removed to insert the substrate and growth source elements, which are mounted in a close-space relationship on a support structure, therein. The support structure is inserted back into the containment means and the plug is form fittedly sealed thereto for performing the epitaxial layering.
Inventors
- 👤 Herbert L. Wilson
- 👤 William A. Guiterrez
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 11:46
CPC Classifications
C; C30; C30B; C30B25/00; C30B25/02; C30B25/22; C30B23/00; C30B23/02; C30B29/00; C30B29/10; C30B29/46; C30B29/48
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
180 words
An apparatus for close-space epitaxial layering in a gas overpressure environment comprising: a high temperature high pressure furnace having an inner chamber made of ceramic material surrounded by insulation material and high pressure resistant metal which are resistant to reaction with materials and gases used in epitaxial layering process; gas flow and pressure control gas feed line means for allowing selective high pressure inert and reducing gases and/or reactive gases to flow therethrough for pressurizing and purging said inner chamber throughout the entire epitaxial process; and a reusable demountable containment means having pressure equalizing vent means in which epitaxial layering processes can be repeatedly performed in a semi-confinement high temperature high gas overpressure environment within said containment means wherein said containment means has a substrate and growth source material therein in close-space area and containment means is positioned within said inner chamber of said furnace during said epitaxial layering process wherein said selective gases are supplied to the interior of said containment means through said pressure equalizing vent means to confine said growth source material flow to said close-space area.
Claim 2
Independent Claim
180 words
An apparatus for close-space epitaxial layering in a gas overpressure environment comprising: a high temperature high pressure furnace having an inner chamber made of ceramic material surrounded by insulation material and high pressure resistant metal which are resistant to reaction with materials and gases used in epitaxial layering process; gas flow and pressure control gas feed line means for allowing selective high pressure inert and reducing gases and/or reactive gases to flow therethrough for pressurizing and purging said inner chamber throughout the entire epitaxial process; and a reusable demountable containment means having pressure equalizing vent means in which epitaxial layering processes can be repeatedly performed in a semi-confinement high temperature high gas overpressure environment within said containment means wherein said containment means has a substrate and growth source material therein in close-space area and containment means is positioned within said inner chamber of said furnace during said epitaxial layering process wherein said selective gases are supplied to the interior of said containment means through said pressure equalizing vent means to confine said growth source material flow to said close-space area.
Claim 3
Dependent Claim
18 words
An apparatus as set forth in claim 1 wherein said ceramic material is an inner wall of alumina.
Claim 4
Dependent Claim
36 words
An apparatus as set forth in claim 2 wherein said reusable demountable containment means is made of a high purity material with a high chemical inertness to the materials and vapors of said epitaxial layering process.
Claim 5
Dependent Claim
41 words
An apparatus as set forth in claim 3 wherein said reusable demountable containment means is specifically made of quartz and has demountable form-fittedly sealed end plugs for loading and unloading substrates and epitaxial growth source materials and their support structures therethrough.
Claim 6
Dependent Claim
28 words
An apparatus as set forth in claim 4 wherein said support structures separate said substrates and said epitaxial growth source materials by a close-space of about 5 millimeters.
Claim 7
Dependent Claim
32 words
An apparatus as set forth in claim 5 wherein said high temperature high pressure furnace is an internally heated furnace with the heater elements inside the pressurized environment of said inner chamber.
Claim 8
Dependent Claim
64 words
An apparatus as set forth in claim 6 wherein said reusable demountable containment means is comprised of a non-fused ampule in which said form-fittedly end plug maybe removed to load said epitaxial growth source material contained in walls of a support structure and a substrate on a substrate support loosely positioned over said support structure and said end plug is reattached to said ampule.
Claim 9
Dependent Claim
72 words
An apparatus as set forth in claim 7 wherein said substrate support is a slide bar which has a mechanical connection thereto leading to a mechanical feedthrough on the outside of said furnace and there are a plurality of said wells containing growth source alloy materials in said support structure whereby said mechanical feed through is used to selectively move said substrate over said plurality of wells during said epitaxialy layering process.
Claim 10
Dependent Claim
59 words
An aparatus as set forth in claim 6 wherein said reusable demountable containment means is comprised of an epitaxial multi-stacked tray assembly in which said form-fittedly end plug is removed to load a plurality of loosely stacked trays therein which alternately hold said growth source materials and said substrates therein and said end plug is reattached to said assembly.
Claim 11
Dependent Claim
22 words
An apparatus as set forth in claim 6 wherein said furnace is positioned with said inner chamber in the horizontally elongated position.
Claim 12
Dependent Claim
31 words
An apparatus as set forth in claim 5 wherein said high temperature high pressure furnace is an externally heated furnace with heater elements outside the pressurized environment of said inner chamber.
Claim 13
Dependent Claim
64 words
An apparatus as set forth in claim 11 wherein said reusable demountable containment means is comprised of a non-fused ampule in which said form-fittedly end plug is removed to load said epitaxial growth source material contained in walls of a support structure and a substrate on a substrate support loosely positioned over said support structure and said end plug is reattached to said ampule.
Claim 14
Dependent Claim
59 words
An apparatus as set forth in claim 11 wherein said reusable demountable containment means is comprised of an epitaxial multi-stacked tray assembly in which said form-fittedly end plug is removed to load a plurality of loosely stacked trays therein which alternately hold said growth source materials and said substrates therein and said end plug is reattached to said assembly.
Claim 15
Dependent Claim
22 words
An apparatus as set forth in claim 11 wherein said furnace is positioned with said inner chamber in the horizontally elongated position.
Claim 16
Dependent Claim
67 words
An apparatus as set forth in claim 11 wherein said reusable demountable containment means and said preheated furnace are moveable with respect to each other wherein said containment means is supported by a support structure and said furnace is moved along a track guide means to completely enclose said containment means during the heat up and epitaxial layering time and is removed therefrom during cool down time.
Claim 17
Dependent Claim
38 words
An apparatus as set forth in claim 1 wherein said high temperature high pressure furnace may be heated to a temperature of more than 750° Celsius at a gas pressure of more than 10,000 pounds per square inch.
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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) | 1990-10-12 | 1991-04-13 | 1991-10-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-10-12 | 1995-04-13 | 1995-10-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-10-12 | 1999-04-13 | 1999-10-13 | $7700.00 | Window Closed / Lapsed |