US5447570A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Purge gas in wafer coating area selection
Assignee: GANUS Inc
•
Filing: 1992-06-23
•
Granted: 1995-09-05
•
Expires: 2012-06-23
Abstract
Abstract Apparatus including a support and purge gas supply prevents edge and backside coating on a wafer in manufacture of integrated circuits. Various enclosure elements and methods are disclosed for containing and directing purge gas, and a CVD system is provided incorporating the elements of the invention.
Inventors
- 👤 Johannes J. Schmitz
- 👤 Frederick J. Scholz
- 👤 Norman L. Turner
- 👤 Raymond L. Chow
- 👤 Frank O. Uher
- 👤 Sien G. Kang
- 👤 Steven C. Selbrede
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:53
CPC Classifications
C; C23; C23C; C23C16/00; C23C16/44; C23C16/455; C23C16/45519; C23C16/45521; C23C16/04; C23C16/042; C23C16/458; C23C16/4582; C23C16/4583; C23C16/4585; H; H10; H10P; H10P72/00; H10P72/70; H10P72/76; H10P72/7604; H10P72/7611
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
159 words
An apparatus for preventing coating on the edge and backside of a wafer during processing in a CVD chamber, comprising: a wafer support within the chamber for supporting the wafer during processing; an enclosure apparatus configured for forming a purge volume around the edge of the wafer substantially separate from the CVD chamber, said enclosure apparatus positionable relative to the wafer to make continuous contact with said wafer support outside the periphery of the wafer and to form a slot of substantially constant height continuously with the frontside of the wafer; and a gas supply system for flowing purge gas to said purge volume, providing pressure in said purge volume greater than the pressure in said CVD chamber during CVD processing, causing a flow of purge gas through said slot and into said CVD chamber; wherein said wafer support has an opening connecting said purge volume with a vacuum pumping system for extracting purge gas from said purge volume.
Claim 2
Independent Claim
159 words
An apparatus for preventing coating on the edge and backside of a wafer during processing in a CVD chamber, comprising: a wafer support within the chamber for supporting the wafer during processing; an enclosure apparatus configured for forming a purge volume around the edge of the wafer substantially separate from the CVD chamber, said enclosure apparatus positionable relative to the wafer to make continuous contact with said wafer support outside the periphery of the wafer and to form a slot of substantially constant height continuously with the frontside of the wafer; and a gas supply system for flowing purge gas to said purge volume, providing pressure in said purge volume greater than the pressure in said CVD chamber during CVD processing, causing a flow of purge gas through said slot and into said CVD chamber; wherein said wafer support has an opening connecting said purge volume with a vacuum pumping system for extracting purge gas from said purge volume.
Claim 3
Dependent Claim
31 words
An apparatus as in claim 1 wherein the enclosure apparatus additionally comprises flexible extensions configured for contacting the wafer on the frontside thereof and within the outer periphery of the wafer.
Claim 4
Independent Claim
133 words
An apparatus for preventing coating on the edge and backside of a wafer during processing in a CVD chamber, comprising: a wafer support within the chamber for supporting the wafer during processing; an enclosure apparatus configured for forming a purge volume around the edge of the wafer substantially separate from the CVD chamber, said enclosure apparatus positionable relative to the wafer to form a first slot with said wafer support outside the periphery of the wafer and to form a second slot continuously with the frontside of the wafer; and a gas supply system for flowing purge gas to said purge volume, providing pressure in said purge volume greater than the pressure in said CVD chamber during CVD processing, causing a flow of purge gas through said slots and into said CVD chamber.
Claim 5
Independent Claim
133 words
An apparatus for preventing coating on the edge and backside of a wafer during processing in a CVD chamber, comprising: a wafer support within the chamber for supporting the wafer during processing; an enclosure apparatus configured for forming a purge volume around the edge of the wafer substantially separate from the CVD chamber, said enclosure apparatus positionable relative to the wafer to form a first slot with said wafer support outside the periphery of the wafer and to form a second slot continuously with the frontside of the wafer; and a gas supply system for flowing purge gas to said purge volume, providing pressure in said purge volume greater than the pressure in said CVD chamber during CVD processing, causing a flow of purge gas through said slots and into said CVD chamber.
Claim 6
Dependent Claim
44 words
An apparatus as in claim 3 wherein said wafer support has a substantially flat surface for contacting the wafer, and said surface has an opening connected to a vacuum pumping system for creating a differential pressure for holding the wafer on said wafer support.
Claim 7
Dependent Claim
30 words
An apparatus as in claim 3 wherein said wafer support has an opening connecting said purge volume with a vacuum pumping system for extracting purge gas from said purge volume.
Claim 8
Dependent Claim
32 words
An apparatus as in claim 3 wherein the enclosure apparatus additionally comprises attached flexible extensions configured for contacting the wafer on the frontside thereof and within the outer periphery of the wafer.
Claim 9
Dependent Claim
40 words
An apparatus as in claim 6 wherein said wafer support is a substantially solid support, and said enclosure apparatus urges said wafer against said wafer support by contact of said attached flexible extensions, holding said wafer against said wafer support.
Claim 10
Dependent Claim
30 words
An apparatus as in claim 6 wherein said wafer support has an opening connecting said purge volume to a vacuum pumping system for extracting purge gas from said purge volume.
Claim 11
Dependent Claim
42 words
An apparatus as in claim 3 wherein the second slot is formed with the frontside of the wafer by contacting the wafer with substantially solid extensions from the enclosure apparatus, the extensions of a length defining the height of said second slot.
Claim 12
Dependent Claim
39 words
An apparatus as in claim 9 wherein said wafer support is a substantially solid support, and said enclosure apparatus urges the wafer against said wafer support by contact of said solid extensions, holding the wafer against said wafer support.
Claim 13
Dependent Claim
30 words
An apparatus as in claim 9 wherein said wafer support has an opening connecting said purge volume to a vacuum pumping system for extracting purge gas from said purge volume.
Claim 14
Independent Claim
155 words
A method for preventing edge and backside coating on a wafer during CVD processing in a CVD chamber, comprising the steps of: placing a wafer on a wafer support in the CVD chamber prior to commencing CVD processing; moving an enclosure means into proximity of said wafer, said enclosure means forming a purge volume around the edge of the wafer by contacting said wafer support continuously outside the periphery of the wafer and forming a slot of substantially constant height continuously with the frontside of the wafer; flowing purge gas into the purge volume, past the edge of the wafer, and through the slot during CVD processing, the purge gas directed into the CVD chamber, opposing coating gas flow to the edge and backside of the wafer; and pumping purge gas out of said purge volume with a vacuum pumping system connected through a passage through said support means and opening into said purge volume.
Claim 15
Independent Claim
155 words
A method for preventing edge and backside coating on a wafer during CVD processing in a CVD chamber, comprising the steps of: placing a wafer on a wafer support in the CVD chamber prior to commencing CVD processing; moving an enclosure means into proximity of said wafer, said enclosure means forming a purge volume around the edge of the wafer by contacting said wafer support continuously outside the periphery of the wafer and forming a slot of substantially constant height continuously with the frontside of the wafer; flowing purge gas into the purge volume, past the edge of the wafer, and through the slot during CVD processing, the purge gas directed into the CVD chamber, opposing coating gas flow to the edge and backside of the wafer; and pumping purge gas out of said purge volume with a vacuum pumping system connected through a passage through said support means and opening into said purge volume.
Claim 16
Dependent Claim
30 words
The method of claim 12 wherein the enclosure apparatus additionally comprises flexible extensions configured for contacting the wafer on the frontside thereof and within the outer periphery of the wafer.
Claim 17
Independent Claim
134 words
A method for preventing edge and backside coating on a wafer during CVD processing in a CVD chamber, comprising the steps of: placing a wafer on a wafer support in the CVD chamber prior to commencing CVD processing; moving an enclosure means into proximity of said wafer, said enclosure means forming a purge volume around the edge of the wafer having a first continuous slot between the enclosure apparatus and said wafer support outside the periphery of the wafer, and a second slot of substantially constant height continuous with the frontside of the wafer; flowing purge gas into the purge volume, past the edge of the wafer, and through the slots during CVD processing, the purge gas directed into the CVD chamber, opposing coating gas flow to the edge and backside of the wafer.
Claim 18
Independent Claim
134 words
A method for preventing edge and backside coating on a wafer during CVD processing in a CVD chamber, comprising the steps of: placing a wafer on a wafer support in the CVD chamber prior to commencing CVD processing; moving an enclosure means into proximity of said wafer, said enclosure means forming a purge volume around the edge of the wafer having a first continuous slot between the enclosure apparatus and said wafer support outside the periphery of the wafer, and a second slot of substantially constant height continuous with the frontside of the wafer; flowing purge gas into the purge volume, past the edge of the wafer, and through the slots during CVD processing, the purge gas directed into the CVD chamber, opposing coating gas flow to the edge and backside of the wafer.
Claim 19
Dependent Claim
43 words
The method of claim 14 wherein said wafer support has a substantially flat surface for contacting the wafer, and said surface has an opening connected to a vacuum pumping system for creating a differential pressure for holding the wafer on said wafer support.
Claim 20
Dependent Claim
29 words
The method of claim 14 wherein said wafer support has an opening connecting said purge volume with a vacuum pumping system for extracting purge gas from said purge volume.
Claim 21
Dependent Claim
31 words
The method of claim 14 wherein the enclosure apparatus additionally comprises attached flexible extensions configured for contacting the wafer on the frontside thereof and within the outer periphery of the wafer.
Claim 22
Dependent Claim
38 words
The method of claim 17 wherein said wafer support is a substantially solid support, and said enclosure apparatus urges said wafer against said wafer support by contact of said flexible extensions, holding said wafer against said wafer support.
Claim 23
Dependent Claim
29 words
The method of claim 17 wherein said wafer support has an opening connecting said purge volume to a vacuum pumping system for extracting purge gas from said purge volume.
Claim 24
Dependent Claim
41 words
The method of claim 14 wherein the second slot is formed with the frontside of the wafer by contacting the wafer with substantially solid extensions from the enclosure apparatus, the extensions of a length defining the height of said second slot.
Claim 25
Dependent Claim
38 words
The method of claim 20 wherein said wafer support is a substantially solid support, and said enclosure apparatus urges the wafer against said wafer support by contact of said solid extensions, holding the wafer against said wafer support.
Claim 26
Dependent Claim
29 words
The method of claim 20 wherein said wafer support has an opening connecting said purge volume to a vacuum pumping system for extracting purge gas from said purge volume.
Claim 27
Independent Claim
177 words
A system for performing CVD coating on a wafer, comprising; a CVD chamber for containing coating gases and said wafer during said coating; a wafer support within said CVD chamber for supporting said wafer during coating; heating means for heating said wafer to a temperature sufficient to initiate CVD coating; an enclosure apparatus configured for forming a purge volume around the edge of the wafer substantially separate from the CVD chamber, said enclosure apparatus positionable relative to the wafer to make continuous contact with said wafer support outside the periphery of the wafer and to form a slot of substantially constant height continuously with the frontside of the wafer; and a gas supply system for flowing purge gas to said purge volume, providing pressure in said purge volume greater than the pressure in said CVD chamber during CVD processing, causing a flow of purge gas through said slot and into said CVD chamber; wherein said wafer support has an opening connecting said purge volume with a vacuum pumping system for extracting purge gas from said purge volume.
Claim 28
Independent Claim
177 words
A system for performing CVD coating on a wafer, comprising; a CVD chamber for containing coating gases and said wafer during said coating; a wafer support within said CVD chamber for supporting said wafer during coating; heating means for heating said wafer to a temperature sufficient to initiate CVD coating; an enclosure apparatus configured for forming a purge volume around the edge of the wafer substantially separate from the CVD chamber, said enclosure apparatus positionable relative to the wafer to make continuous contact with said wafer support outside the periphery of the wafer and to form a slot of substantially constant height continuously with the frontside of the wafer; and a gas supply system for flowing purge gas to said purge volume, providing pressure in said purge volume greater than the pressure in said CVD chamber during CVD processing, causing a flow of purge gas through said slot and into said CVD chamber; wherein said wafer support has an opening connecting said purge volume with a vacuum pumping system for extracting purge gas from said purge volume.
Claim 29
Dependent Claim
31 words
A system as in claim 23 wherein the enclosure apparatus additionally comprises flexible extensions configured for contacting the wafer on the frontside thereof and within the outer periphery of the wafer.
Claim 30
Independent Claim
151 words
A system for performing CVD coating on a wafer, comprising; a CVD chamber for containing coating gases and said wafer during said coating; a wafer support within said CVD chamber for supporting said wafer during coating; heating means for heating said wafer to a temperature sufficient to initiate CVD coating; an enclosure apparatus configured for forming a purge volume around the edge of the wafer substantially separate from the CVD chamber, said enclosure apparatus positionable relative to the wafer to form a first slot with said wafer support outside the periphery of the wafer and to form a second slot continuously with the frontside of the wafer; and a gas supply system for flowing purge gas to said purge volume, providing pressure in said purge volume greater than the pressure in said CVD chamber during CVD processing, causing a flow of purge gas through said slots and into said CVD chamber.
Claim 31
Independent Claim
151 words
A system for performing CVD coating on a wafer, comprising; a CVD chamber for containing coating gases and said wafer during said coating; a wafer support within said CVD chamber for supporting said wafer during coating; heating means for heating said wafer to a temperature sufficient to initiate CVD coating; an enclosure apparatus configured for forming a purge volume around the edge of the wafer substantially separate from the CVD chamber, said enclosure apparatus positionable relative to the wafer to form a first slot with said wafer support outside the periphery of the wafer and to form a second slot continuously with the frontside of the wafer; and a gas supply system for flowing purge gas to said purge volume, providing pressure in said purge volume greater than the pressure in said CVD chamber during CVD processing, causing a flow of purge gas through said slots and into said CVD chamber.
Claim 32
Dependent Claim
44 words
A system as in claim 25 wherein said wafer support has a substantially flat surface for contacting the wafer, and said surface has an opening connected to a vacuum pumping system for creating a differential pressure for holding the wafer on said wafer support.
Claim 33
Dependent Claim
30 words
A system as in claim 25 wherein said wafer support has an opening connecting said purge volume with a vacuum pumping system for extracting purge gas from said purge volume.
Claim 34
Dependent Claim
32 words
A system as in claim 25 wherein the enclosure apparatus additionally comprises attached flexible extensions configured for contacting the wafer on the frontside thereof and within the outer periphery of the wafer.
Claim 35
Dependent Claim
39 words
A system as in claim 28 wherein said wafer support is a substantially solid support, and said enclosure apparatus urges said wafer against said wafer support by contact of said flexible extensions, holding said wafer against said wafer support.
Claim 36
Dependent Claim
30 words
A system as in claim 28 wherein said wafer support has an opening connecting said purge volume to a vacuum pumping system for extracting purge gas from said purge volume.
Claim 37
Dependent Claim
42 words
A system as in claim 25 wherein the second slot is formed with the frontside of the wafer by contacting the wafer with substantially solid extensions from the enclosure apparatus, the extensions of a length defining the height of said second slot.
Claim 38
Dependent Claim
39 words
A system as in claim 31 wherein said wafer support is a substantially solid support, and said enclosure apparatus urges the wafer against said wafer support by contact of said solid extensions, holding the wafer against said wafer support.
Claim 39
Dependent Claim
30 words
A system as in claim 31 wherein said wafer support has an opening connecting said purge volume to a vacuum pumping system for extracting purge gas from said purge volume.
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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) | 1998-09-04 | 1999-03-06 | 1999-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-09-04 | 2003-03-06 | 2003-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-09-04 | 2007-03-06 | 2007-09-05 | $7700.00 | Window Closed / Lapsed |