US3953265A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Meniscus-contained method of handling fluids in the manufacture of semiconductor wafers
Assignee: International Business Machines Corp
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Filing: 1975-04-28
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Granted: 1976-04-27
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Expires: 1995-04-28
Abstract
Abstract The invention relates to a method for reducing the comsumption of etchants used in manufacturing semiconductor devices comprising the steps of supporting a semiconductor wafer, metering a predetermined volume of etchant onto the surface of said wafer to form a meniscus-contained body of etchant thereon, maintaining said wafer static during etching, sensing the completion of said etching, and spinning said wafer upon completion of the etching to remove the etchant from the wafer and terminate the etching operation.
Inventors
- 👤 Roderic Kermit Hood
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:46
CPC Classifications
H; H10; H10P; H10P72/00; H10P72/04; H10P72/0402; H10P72/0418; H10P72/0422; H10P72/0424; H10P72/50; H10W; H10W74/00; H10W74/40; H10W74/47; H10P72/06; H10P72/0604
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
147 words
A method of static etching a deposited layer on a semiconductor wafer, said layer having a developed photoresist pattern engaging its upper surface, comprising, supporting said wafer in a horizontal position with the layer to be etched being located on the upper side of said wafer, metering a predetermined volume of an etchant solution onto the upper surface of said wafer to flow over the entire upper surface up to all edges of said wafer to form a meniscus-contained body of etch solution, statically maintaining said meniscus-contained body while the etch process proceeds towards completeion, sensing the completion of etching by means of an etching end point detector, spinning said waffer to apply centrifugal force to the body of the etch solution immediately upon said sensing step indicating the completion of etching to thereby remove the etchant solution from said wafer and immediately terminate the etching operation.
Claim 2
Independent Claim
147 words
A method of static etching a deposited layer on a semiconductor wafer, said layer having a developed photoresist pattern engaging its upper surface, comprising, supporting said wafer in a horizontal position with the layer to be etched being located on the upper side of said wafer, metering a predetermined volume of an etchant solution onto the upper surface of said wafer to flow over the entire upper surface up to all edges of said wafer to form a meniscus-contained body of etch solution, statically maintaining said meniscus-contained body while the etch process proceeds towards completeion, sensing the completion of etching by means of an etching end point detector, spinning said waffer to apply centrifugal force to the body of the etch solution immediately upon said sensing step indicating the completion of etching to thereby remove the etchant solution from said wafer and immediately terminate the etching operation.
Claim 3
Dependent Claim
94 words
A static etching method as defined in claim 1 in which, said supporting step comprises a motor drive spindle having a horizontal supporting platform connected to its upper end for receiving a wafer in a horizontal position, maintaining said supporting platform in a motionless condition during the metering, statically maintaining, and sensing steps for performing the etching operation, and said spinning step switching power to said motor driven spindle in response to the sensing step to rapidly spin off the body of etchant solution from said wafer by the centrifugal force of rotary motion.
Claim 4
Dependent Claim
93 words
A static etching method as defined in claim 1 further comprising, supporting liquid dispersing means for dispersing said etchant solution and a wash solution, said metering step applying a volume of etchant solution onto the static upper surface of said wafer, the volume not exceeding an amount of the solution which covers the entire wafer surface up to the edges of the wafer with the boundaries on said solution supported by the meniscus of said solution, wherein the volume does not cause any overflow of etchant solution over the edges of said wafer.
Claim 5
Dependent Claim
104 words
A static etchant method as defined in claim 1 further comprising, said sensing step using a light source to provide a light beam through fiber optics passing downwardly through the meniscus-contained fluid body of etchant solution, being reflected by the surface of said wafer to other fiber optics, detecting with a light detector the reflected light rays received through the other fiber optics, the detector providing an electrical signal output, monitoring the changes in the electrical signal output to sense when the signal stops undulating to indicate to the spinning step when the end of the static etching of the deposited layer is completed.
Claim 6
Dependent Claim
47 words
A static etchant method as defined in claim 4, further comprising, supporting a polycarbonate lens in a fluid-proof manner at the end of said fiber optics, with said lens submersed in said body of etchant solution, but said lens is not in contact with the wafer surface.
Claim 7
Dependent Claim
76 words
A method of static etching as defined in claim 1, prior to said supporting step, further comprising, preparing an etchant solution with a wetting agent contained in a proportion to provide a surface tension in the fluid that allows the solution to spread over the surface of the wafer and stop at every edge, whereby a meniscus-contained fluid body of etchant solution is formed before any part of said fluid overflows any edge of said wafer.
Claim 8
Dependent Claim
33 words
A method as defined in claim 6 in which the proportion of wetting agent in the etchant solution is slightly below a lowest proportion of said wetting agent which causes uncontrollable edge overflow.
Claim 9
Independent Claim
350 words
A method of greatly reducing the amount of corrosive operating fluids used in the course of manufacturing integrated circuits at each of plural stages in the manufacture of an integrated circuit in which at each stage an oxide or metal layer is deposited with a photoresist layer being applied thereover and a shape-determining image thereon, comprising the steps of supporting said wafer in a processing chamber in a horizontal position on a platform which can be rapidly rotated with said wafer, the photoresist layer being on the top side of said wafer, firstly metering a predetermined volume of photoresist developing solution onto the upper surface of said wafer to form a meniscus-contained fluid body over the entire upper surface of said wafer while said wafer and platform are in a stationary state, firstly statically maintaining said platform and wafer which the meniscus-contained body of developer fluid until the end of a development period, firstly rotating said supporting platform with said wafer to remove the body of the developing fluid, and firstly spraying said wafer with a washing solution, secondly metering a predetermined volume of an etchant solution onto the upper surface of said wafer to flow over the entire upper surface of said wafer to all edges of said wafer to form a meniscus-contained body of etchant solution while said wafer and platform are in a stationary state, secondly rotating said wafer immediately upon the completion of etching to rapidly terminate the etching operation, and secondly spraying said wafer with a washing solution, thirdly metering a predtermined volume of photoresist stripping solution onto the upper surface of said wafer to flow over the entire upper surface to all edges of said wafer to form a meniscus-contained body of stripping solution while said wafer and platform are in a stationary state, thirdly statically maintaining said meniscus-contained body of stripping fluid until the stripping process is completed, thirdly rotating said wafer upon the completion of said stripping step to remove the stripping solution from said wafer, thirdly spraying said wafer with a wash solution, and thirdly spinning said wafer to dry it.
Claim 10
Independent Claim
350 words
A method of greatly reducing the amount of corrosive operating fluids used in the course of manufacturing integrated circuits at each of plural stages in the manufacture of an integrated circuit in which at each stage an oxide or metal layer is deposited with a photoresist layer being applied thereover and a shape-determining image thereon, comprising the steps of supporting said wafer in a processing chamber in a horizontal position on a platform which can be rapidly rotated with said wafer, the photoresist layer being on the top side of said wafer, firstly metering a predetermined volume of photoresist developing solution onto the upper surface of said wafer to form a meniscus-contained fluid body over the entire upper surface of said wafer while said wafer and platform are in a stationary state, firstly statically maintaining said platform and wafer which the meniscus-contained body of developer fluid until the end of a development period, firstly rotating said supporting platform with said wafer to remove the body of the developing fluid, and firstly spraying said wafer with a washing solution, secondly metering a predetermined volume of an etchant solution onto the upper surface of said wafer to flow over the entire upper surface of said wafer to all edges of said wafer to form a meniscus-contained body of etchant solution while said wafer and platform are in a stationary state, secondly rotating said wafer immediately upon the completion of etching to rapidly terminate the etching operation, and secondly spraying said wafer with a washing solution, thirdly metering a predtermined volume of photoresist stripping solution onto the upper surface of said wafer to flow over the entire upper surface to all edges of said wafer to form a meniscus-contained body of stripping solution while said wafer and platform are in a stationary state, thirdly statically maintaining said meniscus-contained body of stripping fluid until the stripping process is completed, thirdly rotating said wafer upon the completion of said stripping step to remove the stripping solution from said wafer, thirdly spraying said wafer with a wash solution, and thirdly spinning said wafer to dry it.
References Cited (Backward Citations)
US3437543A
Cited
US3489608A
Cited
US3597289A
Cited
US3765984A
Cited
US3841930A
Cited
US3874959A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-04-27 | 1979-10-27 | 1980-04-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-04-27 | 1983-10-27 | 1984-04-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-04-27 | 1987-10-27 | 1988-04-27 | $7700.00 | Window Closed / Lapsed |