US5229171A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus and method for uniformly coating a substrate in an evacuable chamber
Assignee: RTI International
•
Filing: 1991-12-23
•
Granted: 1993-07-20
•
Expires: 2011-12-23
Abstract
Abstract An apparatus and method including a droplet coating generator for generating a stream of electrically charged coating droplets within an evacuable chamber towards a substrate positioned within the evacuable chamber. A piezoelectric vibrator and orifice plate coupled thereto generate the stream of coating droplets. The coating droplets are urged to move in a sweeping motion across the substrate by at least one pair of opposing spaced apart electrodes powered by an electrical power supply. A uniform coating is thus produced while the evacuable chamber is maintained at subatmospheric pressure as required during typical semiconductor processing. Multiple applications of a photoresist coating may be applied by the coating apparatus without requiring that the evacuable chamber be repeatedly vented and pumped down to subatmospheric pressure.
Inventors
- 👤 Robert P. Donovan
- 👤 Ravindran Periasamy
- 👤 Anthony C. Clayton
- 👤 David S. Ensor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 02:16
CPC Classifications
H; H10; H10P; H10P72/00; H10P72/04; H10P72/0448; B; B05; B05B; B05B5/00; B05B5/025; B05B5/043; B05B5/053; B05B5/0531; B05D; B05D1/00; B05D1/02; B05D1/04; B05D3/00; B05D3/04; B05D3/0493; G; G03; G03F; G03F7/00; G03F7/16; G03F7/164; Y; Y10; Y10S; Y10S430/00; Y10S430/136
Claims Analysis
Total Claims: 42
Claim 1
Independent Claim
126 words
An apparatus for depositing a coating onto a substrate, said apparatus comprising: an evacuable chamber; a substrate holder positioned within said evacuable chamber; a coating droplet generator communicating with said evacuable chamber for generating a stream of electrically charged coating droplets towards a substrate positioned on said substrate holder with said evacuable chamber maintained at a subatmospheric pressure; at least one pair of electrodes positioned in opposing spaced apart relation around the stream of electrically charged coating droplets; and an electrical power supply connected to said at least one pair of electrodes for applying a time varying electric field to the stream of electrically charged coating droplets and causing the stream of electrically charged coating droplets to sweep across the substrate and uniformly cover the substrate.
Claim 2
Independent Claim
126 words
An apparatus for depositing a coating onto a substrate, said apparatus comprising: an evacuable chamber; a substrate holder positioned within said evacuable chamber; a coating droplet generator communicating with said evacuable chamber for generating a stream of electrically charged coating droplets towards a substrate positioned on said substrate holder with said evacuable chamber maintained at a subatmospheric pressure; at least one pair of electrodes positioned in opposing spaced apart relation around the stream of electrically charged coating droplets; and an electrical power supply connected to said at least one pair of electrodes for applying a time varying electric field to the stream of electrically charged coating droplets and causing the stream of electrically charged coating droplets to sweep across the substrate and uniformly cover the substrate.
Claim 3
Dependent Claim
24 words
The coating apparatus according to claim 1 wherein said coating droplet generator is positioned in opposing spaced apart vertical relation above said substrate holder.
Claim 4
Dependent Claim
27 words
The coating apparatus according to claim 1 wherein said coating droplet generator includes means for controlling the electrical charge on the stream of electrically charged coating droplets.
Claim 5
Dependent Claim
31 words
The coating apparatus according to claim 1 wherein said coating droplet generator comprises a piezoelectric vibrator and an orifice plate coupled thereto for generating the stream of electrically charged coating droplets.
Claim 6
Dependent Claim
21 words
The coating apparatus according to claim 4 further comprising a second alternating current electrical power supply connected to said piezoelectric vibrator.
Claim 7
Dependent Claim
33 words
The coating apparatus according to claim 1 wherein said electrical power supply is an alternating current electrical power supply for powering said at least one pair of electrodes at an alternating current frequency.
Claim 8
Dependent Claim
27 words
The coating apparatus according to claim 6 wherein said at least one pair of opposing spaced apart electrodes are positioned adjacent opposite ends of said substrate holder.
Claim 9
Dependent Claim
21 words
The coating apparatus according to claim 7 wherein said at least one pair of electrodes is positioned outside said evacuable chamber.
Claim 10
Dependent Claim
80 words
The coating apparatus according to claim 1 further comprising a tubular alignment bellows and a collimating tube each having first and second opposing open ends, wherein the first open end of said tubular alignment bellows is connected to said coating droplet generator, wherein the second open end of said tubular alignment bellows is connected to the first open end of said collimating tube, and wherein the second open end of said collimating tube is in communication with said evacuable chamber.
Claim 11
Independent Claim
138 words
An apparatus for uniformly depositing a coating onto a substrate, said apparatus comprising: an evacuable chamber; a substrate holder positioned within said evacuable chamber; a coating droplet generator communicating with said evacuable chamber, said coating droplet generator comprising a piezoelectric vibrator and an orifice plate coupled thereto for generating a stream of electrically charged coating droplets towards a substrate positioned on said substrate holder; a first pair and a second pair of opposing spaced apart electrodes positioned surrounding the stream of electrically charged coating droplets; and an electrically power supply connected to each of said first and second pairs of opposing spaced apart electrodes for applying a time varying electric field to the stream of electrically charged coating droplets and causing the stream of electrically charged coating droplets to sweep across the substrate and uniformly cover the substrate.
Claim 12
Independent Claim
138 words
An apparatus for uniformly depositing a coating onto a substrate, said apparatus comprising: an evacuable chamber; a substrate holder positioned within said evacuable chamber; a coating droplet generator communicating with said evacuable chamber, said coating droplet generator comprising a piezoelectric vibrator and an orifice plate coupled thereto for generating a stream of electrically charged coating droplets towards a substrate positioned on said substrate holder; a first pair and a second pair of opposing spaced apart electrodes positioned surrounding the stream of electrically charged coating droplets; and an electrically power supply connected to each of said first and second pairs of opposing spaced apart electrodes for applying a time varying electric field to the stream of electrically charged coating droplets and causing the stream of electrically charged coating droplets to sweep across the substrate and uniformly cover the substrate.
Claim 13
Dependent Claim
24 words
The coating apparatus according to claim 10 wherein said coating droplet generator is positioned in opposing spaced apart vertical relation above said substrate holder.
Claim 14
Dependent Claim
42 words
The coating apparatus according to claim 10 wherein said coating droplet generator further comprises a ring electrode positioned adjacent said orifice plate and adapted to be connected to a second electrical power supply for controlling the electrical charge on the coating droplets.
Claim 15
Dependent Claim
21 words
The coating apparatus according to claim 12 further comprising a third alternating current electrical power supply connected to said piezoelectric vibrator.
Claim 16
Dependent Claim
36 words
The coating apparatus according to claim 10 wherein said electrical power supply is an alternating current electrical power supply for powering each of said first and second pairs of opposing electrodes at an alternating current frequency.
Claim 17
Dependent Claim
35 words
The coating apparatus according to claim 14 wherein said alternating current electrical power supply includes means for powering said first pair of electrodes at an alternating current frequency different from said second pair of electrodes.
Claim 18
Dependent Claim
46 words
The coating apparatus according to claim 15 wherein said alternating current electrical power supply includes means for powering said first pair of electrodes at a frequency of about 1.5 Hertz and said second pair of electrodes at a frequency of not more than about 1.5 Hertz.
Claim 19
Dependent Claim
27 words
The coating apparatus according to claim 14 wherein said at least one pair of opposing spaced apart electrodes are positioned adjacent opposite ends of said substrate holder.
Claim 20
Dependent Claim
21 words
The coating apparatus according to claim 17 wherein said first and second pairs of electrodes are positioned outside said evacuable chamber.
Claim 21
Dependent Claim
80 words
The coating apparatus according to claim 10 further comprising a tubular alignment bellows and a collimating tube each having first and second opposing open ends, wherein the first open end of said tubular alignment bellows is connected to said coating droplet generator, wherein the second open end of said tubular alignment bellows is connected to the first open end of said collimating tube, and wherein the second open end of said collimating tube is in communication with said evacuable chamber.
Claim 22
Independent Claim
181 words
An apparatus for depositing a coating onto a substrate within an evacuable chamber, the evacuable chamber including a substrate holder positioned therein, said apparatus comprising: a coating droplet generator adapted to be coupled in communication with the evacuable chamber for generating a stream of electrically charged coating droplets, such that the stream of electrically charged coating droplets is directed towards a substrate positioned on the substrate holder with the evacuable chamber maintained at a subatmospheric pressure, when said coating droplet generator is coupled to the evacuable chamber; at least one pair of electrodes adapted to be positioned in opposing spaced apart relation around the stream of electrically charged coating droplets; and an electrical power supply connected to said at least one pair of electrodes for applying a time varying electric field to the stream of electrically charged coating droplets and causing the stream of electrically charged coating droplets to sweep across the substrate and uniformly cover the substrate, when said at least one pair of electrodes is positioned in opposing spaced apart relation around the stream of electrically charged coating droplets.
Claim 23
Independent Claim
181 words
An apparatus for depositing a coating onto a substrate within an evacuable chamber, the evacuable chamber including a substrate holder positioned therein, said apparatus comprising: a coating droplet generator adapted to be coupled in communication with the evacuable chamber for generating a stream of electrically charged coating droplets, such that the stream of electrically charged coating droplets is directed towards a substrate positioned on the substrate holder with the evacuable chamber maintained at a subatmospheric pressure, when said coating droplet generator is coupled to the evacuable chamber; at least one pair of electrodes adapted to be positioned in opposing spaced apart relation around the stream of electrically charged coating droplets; and an electrical power supply connected to said at least one pair of electrodes for applying a time varying electric field to the stream of electrically charged coating droplets and causing the stream of electrically charged coating droplets to sweep across the substrate and uniformly cover the substrate, when said at least one pair of electrodes is positioned in opposing spaced apart relation around the stream of electrically charged coating droplets.
Claim 24
Dependent Claim
30 words
The apparatus according t claim 20 wherein said coating droplet generator comprises a piezoelectric vibrator and an orifice plate coupled thereto for generating the stream of electrically charged coating droplets.
Claim 25
Dependent Claim
38 words
The apparatus according to claim 21 wherein said coating droplet generator further comprises a ring electrode positioned adjacent said orifice plate for connection to a second electrical power supply for controlling the electrical charge on the coating droplets.
Claim 26
Dependent Claim
20 words
The apparatus according to claim 22 further comprising a third alternating current electrical power supply connected to said piezoelectric vibrator.
Claim 27
Dependent Claim
32 words
The apparatus according to claim 20 wherein said electrical power supply is an alternating current electrical power supply for powering said at least one pair of electrodes at an alternating current frequency.
Claim 28
Independent Claim
75 words
A method for depositing a coating onto a substrate positioned within an evacuable chamber, said method comprising the steps of: generating a stream of electrically charged coating droplets towards the substrate positioned within the evacuable chamber while maintaining the evacuable chamber at subatmospheric pressure; and applying a time varying electrical field to the stream of electrically charged coating droplets to thereby sweep the electrically charged coating droplets across the substrate and uniformly cover the substrate.
Claim 29
Independent Claim
75 words
A method for depositing a coating onto a substrate positioned within an evacuable chamber, said method comprising the steps of: generating a stream of electrically charged coating droplets towards the substrate positioned within the evacuable chamber while maintaining the evacuable chamber at subatmospheric pressure; and applying a time varying electrical field to the stream of electrically charged coating droplets to thereby sweep the electrically charged coating droplets across the substrate and uniformly cover the substrate.
Claim 30
Dependent Claim
39 words
The method according to claim 25 wherein the step of generating a stream of electrically charged coating droplets towards the substrate comprises the step of generating the stream of coating droplets in a downward vertical direction to the substrate.
Claim 31
Dependent Claim
21 words
The method according to claim 25 further comprises the step of controlling the electrical charge on the electrically charged coating droplets.
Claim 32
Dependent Claim
36 words
The method according to claim 25 wherein the applying step comprises the step of electrically powering at least one pair of opposing spaced apart electrodes around the stream of coating droplets at an alternating current frequency.
Claim 33
Dependent Claim
39 words
The method according to claim 25 wherein the applying step comprises the step of electrically powering a first pair and a second pair of opposing spaced apart electrodes surrounding the stream of coating droplets at an alternating current frequency.
Claim 34
Dependent Claim
40 words
The method according to claim 29 wherein the step of electrically powering the first pair and second pair of opposing spaced apart electrodes comprises powering the first pair of electrodes at a different frequency than the second pair of electrodes.
Claim 35
Independent Claim
93 words
A method for processing a substrate positioned within an evacuable chamber, said method comprising the steps of: generating a stream of electrically charged photoresist coating droplets towards a substrate positioned within the evacuable chamber while maintaining the evacuable chamber at subatmospheric pressure; applying a time varying electric field to the stream of electrically charged photoresist droplets to thereby sweep the electrically charged photoresist coating droplets across the substrate to uniformly cover the substrate with photoresist; and selectively exposing the photoresist coating on the substrate to radiation to form a pattern on the substrate.
Claim 36
Independent Claim
93 words
A method for processing a substrate positioned within an evacuable chamber, said method comprising the steps of: generating a stream of electrically charged photoresist coating droplets towards a substrate positioned within the evacuable chamber while maintaining the evacuable chamber at subatmospheric pressure; applying a time varying electric field to the stream of electrically charged photoresist droplets to thereby sweep the electrically charged photoresist coating droplets across the substrate to uniformly cover the substrate with photoresist; and selectively exposing the photoresist coating on the substrate to radiation to form a pattern on the substrate.
Claim 37
Dependent Claim
31 words
The method according to claim 31 further comprising the step of processing the substrate with the photoresist pattern formed on the substrate while the evacuable chamber is maintained at subatmospheric pressure.
Claim 38
Dependent Claim
40 words
The method according to claim 31 wherein the step of generating a stream of electrically charged photoresist coating droplets towards the substrate comprises the step of generating the stream of coating droplets in a downward vertical direction to the substrate.
Claim 39
Dependent Claim
22 words
The method according to claim 31 further comprising the step of controlling the electrical charge on the electrically charged photoresist coating droplets.
Claim 40
Dependent Claim
53 words
The method according to claim 31 wherein the step of urging the electrically charged photoresist coating droplets to move in a sweeping motion across the substrate comprises the step of electrically powering at least one pair of opposing spaced apart electrodes around the stream of photoresist coating droplets at an alternating current frequency.
Claim 41
Dependent Claim
54 words
The method according to claim 31 wherein the step of urging the electrically charged photoresist coating droplets to move in a sweeping motion across the substrate comprises the step of electrically powering a first pair and a second pair of opposing spaced apart electrodes surrounding the stream of photoresist coating droplets with alternating current.
Claim 42
Dependent Claim
40 words
The method according to claim 36 wherein the step of electrically powering the first pair and second pair of opposing spaced apart electrodes. comprises powering the first pair of electrodes at a different frequency than the second pair of electrodes.
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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) | 1996-07-19 | 1997-01-18 | 1997-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-07-19 | 2001-01-18 | 2001-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-07-19 | 2005-01-18 | 2005-07-20 | $7700.00 | Window Closed / Lapsed |