US4834834A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Laser photochemical etching using surface halogenation
Assignee: United States Department of the Air Force
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Filing: 1987-11-20
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Granted: 1989-05-30
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Expires: 2007-11-20
Abstract
Abstract A method for maskless patterning and etching of metals is disclosed. The method comprises the steps of providing a metal, forming a passivating layer of an oxide or nitride upon the surface of the metal, exposing the metal to a halogenous atmosphere, while patterning the metal using a directed energy beam to selectively replace the oxides or nitrides with halides, and heating the patterned metal while exposing it to an etchant to etch regions located below the halogenated surfaces leaving the remaining passivated regons intact.
Inventors
- 👤 Daniel J. Ehrlich
- 👤 Mordecai Rothschild
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 07:57
CPC Classifications
C; C23; C23F; C23F4/00; G; G03; G03F; G03F7/00; G03F7/20; G03F7/2041; G03F7/2043; H; H05; H05K; H05K3/00; H05K3/02; H05K3/06; H05K3/061
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
139 words
A method for maskless patterning of surfaces of metal film coatings on substrates comprising the steps of: (a) providing a metal film on a substrate; (b) exposing the film to an atmosphere containing a passivating layer upon the exposed surfaces of the metal film; (c) exposing the surface passivated structure to an atmosphere containing a halogen; (d) patterning the passivated structure by directing a beam of energy toward the passivated structure in the presence of the halogen to selectively form metal halides of said halogen in selected regions of the passivated surface where said beam is directed, and leaving a remaining passivated surface on other regions; and (e) exposing the patterned passivated structure to an atmosphere containing an etchant while heating the patterned passivated surface, thereby etching the metal in the pattern while leaving the remaining passivated surface intact.
Claim 2
Independent Claim
139 words
A method for maskless patterning of surfaces of metal film coatings on substrates comprising the steps of: (a) providing a metal film on a substrate; (b) exposing the film to an atmosphere containing a passivating layer upon the exposed surfaces of the metal film; (c) exposing the surface passivated structure to an atmosphere containing a halogen; (d) patterning the passivated structure by directing a beam of energy toward the passivated structure in the presence of the halogen to selectively form metal halides of said halogen in selected regions of the passivated surface where said beam is directed, and leaving a remaining passivated surface on other regions; and (e) exposing the patterned passivated structure to an atmosphere containing an etchant while heating the patterned passivated surface, thereby etching the metal in the pattern while leaving the remaining passivated surface intact.
Claim 3
Dependent Claim
25 words
A method of claim 1 in which the metal film is selected from the group consisting of molybdenum, tungsten, aluminum, chromium, niobium, tantalum and vanadium.
Claim 4
Dependent Claim
14 words
A method as in claim 1 in which the halogen is Cl 2 .
Claim 5
Dependent Claim
13 words
A method as in claim 1 in which etchant is NF 3 .
Claim 6
Dependent Claim
25 words
A method as in claim 1 in which the passivating agent is selected from the group consisting of fluids containing oxygen and fluids containing nitrogen.
Claim 7
Dependent Claim
36 words
A method as in claim 5 wherein the passivating agent is selected from the group consisting of O 2 , N 2 , O 3 , NO 2 , N 2 O and NH 3 .
Claim 8
Dependent Claim
27 words
A method as in claim 1 in which the patterning step includes directing a beam of ultraviolet laser energy onto the passivated surface to define patterned regions.
Claim 9
Dependent Claim
27 words
A method as in claim 1 in which the patterning step includes directing a beam of a visible laser onto the passivated surface to define patterned regions.
Claim 10
Dependent Claim
14 words
A method as in claim 8 in which the laser is an ion laser.
Claim 11
Dependent Claim
26 words
A method as in claim 1 in which the beam of energy is selected from the group consisting of focused ion beams and focused electron beams.
Claim 12
Dependent Claim
24 words
A method as in claim 1 in which the etching step includes irradiating the patterned, passivated surface with unfocused, broad beam ultraviolet laser energy.
Claim 13
Dependent Claim
27 words
A method as in claim 1 in which the etching step includes irradiating the patterned, passivated surface with unfocused, broad beam energy provided by an ion laser.
Claim 14
Dependent Claim
21 words
A method as in claim 1 in which the etching step includes heating the patterned, passivated surface with a radiant heater.
Claim 15
Dependent Claim
21 words
A method as in claim 1 in which the etching step includes heating the patterned, passivated surface with a flood illuminator.
Claim 16
Dependent Claim
22 words
A method as in claim 1 in which the etching step includes heating the patterned, passivated surface with a thermally conductive heater.
Claim 17
Dependent Claim
24 words
A method as in claim 1 in which the substrate is selected from the group consisting of silicon, gallium arsenide, germanium, and silicon dioxide.
Claim 18
Independent Claim
134 words
A method for patterning surfaces of metals comprising the steps of: (a) providing a metal; (b) exposing the metal to an atmosphere containing a passivating agent to form a surface passivating layer upon the exposed surfaces of the metal; (c) exposing the surface passivated structure to a halogen-containing atmosphere; (d) patterning the passivated structure by directing a beam source of optical energy toward the passivated structure in the presence of said halogen to selectively form metal halides of said halogen on selected regions of the passivated surface where said beam is directed and leaving a remaining passivated surface on other regions; and (e) exposing the patterned passivated structure to an atmosphere containing an etchant while heating the patterned passivated surface, thereby etching the metal in the pattern while leaving the remaining passivated surface intact.
Claim 19
Independent Claim
134 words
A method for patterning surfaces of metals comprising the steps of: (a) providing a metal; (b) exposing the metal to an atmosphere containing a passivating agent to form a surface passivating layer upon the exposed surfaces of the metal; (c) exposing the surface passivated structure to a halogen-containing atmosphere; (d) patterning the passivated structure by directing a beam source of optical energy toward the passivated structure in the presence of said halogen to selectively form metal halides of said halogen on selected regions of the passivated surface where said beam is directed and leaving a remaining passivated surface on other regions; and (e) exposing the patterned passivated structure to an atmosphere containing an etchant while heating the patterned passivated surface, thereby etching the metal in the pattern while leaving the remaining passivated surface intact.
Claim 20
Dependent Claim
25 words
A method as in claim 17 in which the passivating agent is selected from the group consisting of fluids containing oxygen and fluids containing nitrogen.
Claim 21
Dependent Claim
36 words
A method as in Claim 18 wherein the passivating agent is selected from the group consisting of O 2 , N 2 , O 3 , NO 2 , N 2 O and NH 3 .
Claim 22
Independent Claim
161 words
A method for maskless patterning of surfaces of refractory metal film coatings on substrates comprising the steps of: (a) providing a refractory metal film on a substrate; (b) exposing the film to oxygen to form an oxide layer upon the exposed surfaces of the metal film; (c) exposing the refractory metal film to an atmosphere comprising gaseous Cl 2 ; (d) focusing the beam of an ion laser onto the metal film in the presence of said Cl 2 to selectively form refractory metal chlorides in selected regions on the metal film where said laser beam is directed; (e) replacing the gaseous Cl 2 atmosphere with an atmosphere comprising gaseous NF 3 ; and (f) exposing the refractory metal film in the presence of said NF 3 to an unfocused, broad ion laser beam to heat the refractory metal film surface and selectively etch portions of the refractory metal film thereby providing an etched, patterned refractory metal film on a substrate.
Claim 23
Independent Claim
161 words
A method for maskless patterning of surfaces of refractory metal film coatings on substrates comprising the steps of: (a) providing a refractory metal film on a substrate; (b) exposing the film to oxygen to form an oxide layer upon the exposed surfaces of the metal film; (c) exposing the refractory metal film to an atmosphere comprising gaseous Cl 2 ; (d) focusing the beam of an ion laser onto the metal film in the presence of said Cl 2 to selectively form refractory metal chlorides in selected regions on the metal film where said laser beam is directed; (e) replacing the gaseous Cl 2 atmosphere with an atmosphere comprising gaseous NF 3 ; and (f) exposing the refractory metal film in the presence of said NF 3 to an unfocused, broad ion laser beam to heat the refractory metal film surface and selectively etch portions of the refractory metal film thereby providing an etched, patterned refractory metal film on a substrate.
Claim 24
Dependent Claim
25 words
A method as in claim 20 wherein the refractory metal is selected from the group consisting of molybdenum, tungsten, aluminum, chromium, niobium, tantalum and vanadium.
Claim 25
Independent Claim
175 words
A method for patterning of surfaces of metal film coatings on substrates comprising: (a) providing a metal film on a substrate; (b) exposing the film to an atmosphere containing a passivating agent to form a surface passivating layer upon the exposed surfaces of the surface passivating layer; (c) applying a photoresist layer over the surface passivating layer; (d) patterning the photoresist; (e) exposing the patterned photoresist to an atmosphere containing a halogen; (f) patterning the film by illuminating the surface with light having a wavelength between about 350 to about 550 nm in the presence of the halogen to selectively form metal halides of said halogen in selected regions of the metal film where said photoresist has been removed thereby driving out the passivating agent in said selected regions and leaving a remaining passivated surface on other regions; (g) removing the photoresist; and (h) exposing the patterned metal film to an atmosphere containing an etchant while heating the patterned metal film, thereby etching the metal in the pattern while leaving the remaining passivated surface intact.
Claim 26
Independent Claim
175 words
A method for patterning of surfaces of metal film coatings on substrates comprising: (a) providing a metal film on a substrate; (b) exposing the film to an atmosphere containing a passivating agent to form a surface passivating layer upon the exposed surfaces of the surface passivating layer; (c) applying a photoresist layer over the surface passivating layer; (d) patterning the photoresist; (e) exposing the patterned photoresist to an atmosphere containing a halogen; (f) patterning the film by illuminating the surface with light having a wavelength between about 350 to about 550 nm in the presence of the halogen to selectively form metal halides of said halogen in selected regions of the metal film where said photoresist has been removed thereby driving out the passivating agent in said selected regions and leaving a remaining passivated surface on other regions; (g) removing the photoresist; and (h) exposing the patterned metal film to an atmosphere containing an etchant while heating the patterned metal film, thereby etching the metal in the pattern while leaving the remaining passivated surface intact.
Claim 27
Independent Claim
145 words
A method for patterning of surfaces of metal film coatings on substrates comprising: (a) providing a metal film on a substrate; (b) exposing the film to an atmosphere containing a passivating agent to form a surface passivating layer upon the exposed surfaces of the metal film; (c) exposing the surface passivated metal film to an atmosphere containing a halogen; (d) patterning the film by projecting the image of a prefabricated mask toward the metal film in the presence of the halogen to selectively form metal halides of said halogen in selected regions of the surface passivating layer where the image is projected thereby driving out the passivating agent in said selected regions; and, (e) exposing the patterned metal film to an atmosphere containing an etchant while heating the patterned metal film, thereby etching the metal in the pattern while leaving the remaining passivated surface intact.
Claim 28
Independent Claim
145 words
A method for patterning of surfaces of metal film coatings on substrates comprising: (a) providing a metal film on a substrate; (b) exposing the film to an atmosphere containing a passivating agent to form a surface passivating layer upon the exposed surfaces of the metal film; (c) exposing the surface passivated metal film to an atmosphere containing a halogen; (d) patterning the film by projecting the image of a prefabricated mask toward the metal film in the presence of the halogen to selectively form metal halides of said halogen in selected regions of the surface passivating layer where the image is projected thereby driving out the passivating agent in said selected regions; and, (e) exposing the patterned metal film to an atmosphere containing an etchant while heating the patterned metal film, thereby etching the metal in the pattern while leaving the remaining passivated surface intact.
Claim 29
Independent Claim
93 words
An apparatus for patterning of surfaces of metal film coatings on a substrate comprising: (a) a deposition chamber; (b) means for supporting the substrate in the chamber; (c) means for providing a patterning gas within the chamber; (d) means for providing energy to pattern the substrate surface; (e) means for translating the energy on the substrate surface; (f) means for replacing the patterning gas within the chamber with an etchant gas; and (g) means for heating the substrate in the presence of the etchant gas to thereby etch the surface of the substrate.
Claim 30
Independent Claim
93 words
An apparatus for patterning of surfaces of metal film coatings on a substrate comprising: (a) a deposition chamber; (b) means for supporting the substrate in the chamber; (c) means for providing a patterning gas within the chamber; (d) means for providing energy to pattern the substrate surface; (e) means for translating the energy on the substrate surface; (f) means for replacing the patterning gas within the chamber with an etchant gas; and (g) means for heating the substrate in the presence of the etchant gas to thereby etch the surface of the substrate.
Claim 31
Dependent Claim
35 words
An apparatus as in claim 24 wherein the means for providing energy to pattern the substrate surface is selected from the group consisting of UV lasers, visible lasers electron beam sources and ion beam sources.
Claim 32
Dependent Claim
27 words
An apparatus as in claim 24 wherein the heating means is selected from the group consisting of unfocused lasers, flood illuminators, radiant heaters and thermally conductive heaters.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-05-29 | 1992-11-28 | 1993-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-05-29 | 1996-11-28 | 1997-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-05-29 | 2000-11-28 | 2001-05-30 | $7700.00 | Window Closed / Lapsed |