US5591564A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gamma ray techniques applicable to semiconductor lithography
Assignee: LSI Corp
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Filing: 1993-04-30
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Granted: 1997-01-07
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Expires: 2013-04-30
Abstract
Abstract Fine, sub-micron line features and patterns are created in a sensitized layer on a semiconductor wafer by a beam of Gamma-radiation. A continuous stream of such radiation, such as provided by a pellet of Cobalt-60, is collimated into a fine beam by a tapered collimator, and is gated on and off by a shutter mechanism comprising a distortable-surface device and a beam-blocking device. The fine, collimated beam converts points in a gamma-radiation-sensitive layer on a semiconductor wafer. By moving the wafer relative to the beam (or vice-versa), patterns are created in the layer of radiation-sensitive layer for further processing a layer underlying the radiation-sensitive layer.
Inventors
- 👤 Michael D. Rostoker
- 👤 Nicholas F. Pasch
- 👤 Joe Zelayeta
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 21:06
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/70; G03F7/70008; G03F7/70216; G03F7/7035; G03F7/70375
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
45 words
Semiconductor lithography apparatus, comprising: a) a source emitting gamma-radiation emissions towards a surface of a semiconductor wafer; and b) apparatus, between said source and said wafer, for causing said gamma-radiation emissions to pattern a layer of resist material applied to the surface of said wafer.
Claim 2
Dependent Claim
45 words
Semiconductor lithography apparatus, comprising: a) a source emitting gamma-radiation emissions towards a surface of a semiconductor wafer; and b) apparatus, between said source and said wafer, for causing said gamma-radiation emissions to pattern a layer of resist material applied to the surface of said wafer.
Claim 3
Dependent Claim
25 words
Semiconductor lithography apparatus according to claim 1, further comprising: a reflector apparatus, upstream of said source for directing said gamma-radiation emissions downstream toward said wafer.
Claim 4
Dependent Claim
18 words
Semiconductor lithography apparatus according to claim 2, wherein: said apparatus for directing the gamma-radiation emissions is a reflector.
Claim 5
Dependent Claim
28 words
Semiconductor lithography apparatus according to claim 1, further comprising: apparatus, between said source and said wafer, for concentrating and intensifying said gamma radiation into a collimated intense beam.
Claim 6
Dependent Claim
18 words
Semiconductor lithography apparatus according to claim 4, wherein: said apparatus for concentrating and intensifying is an afocal concentrator.
Claim 7
Dependent Claim
115 words
Semiconductor lithography apparatus according to claim 5, wherein the afocal concentrator further comprises: a) a hollow, tapered section having a broad mouth of a first diameter at an upstream end of said tapered section, and a narrow opening of a second diameter at a downstream end of said tapered section, and a first bore extending between said broad mouth and said narrow opening; b) a hollow cylindrical section, disposed downstream of said tapered section, having a second bore with a diameter equal to said second diameter, and formed continuously with said narrow opening at said downstream end of said tapered section; and c) inside surfaces of said first and second bores are reflective to gamma-radiation.
Claim 8
Dependent Claim
19 words
Semiconductor lithography apparatus according to claim 6, wherein: the tapered section of the afocal concentrator has a conically-tapered shape.
Claim 9
Dependent Claim
17 words
Semiconductor lithography apparatus according to claim 6, wherein: the tapered section of the afocal concentrator is horn-shaped.
Claim 10
Dependent Claim
18 words
Semiconductor lithography apparatus according to claim 6, wherein: the inside surface of the bore is coated with aluminum.
Claim 11
Dependent Claim
18 words
Semiconductor lithography apparatus according to claim 6, wherein: the inside surface of the bore is coated with nickel.
Claim 12
Dependent Claim
18 words
Semiconductor lithography apparatus according to claim 6, wherein: the inside surface of the bore is coated with chromium.
Claim 13
Dependent Claim
18 words
Semiconductor lithography apparatus according to claim 6, wherein: the first diameter is in the range of 50-60 microns.
Claim 14
Dependent Claim
16 words
Semiconductor lithography apparatus according to claim 6, wherein: the second diameter is less than 0.5 microns.
Claim 15
Dependent Claim
22 words
Semiconductor lithography apparatus according to claim 1, further comprising: apparatus, disposed between the source and the wafer, for gating the radiation source.
Claim 16
Dependent Claim
20 words
Semiconductor lithography apparatus according to claim 14, wherein: said apparatus for gating the radiation source is a high-speed gamma-radiation shutter.
Claim 17
Dependent Claim
80 words
Semiconductor lithography apparatus according to claim 15 wherein the high-speed radiation shutter further comprises: a) a surface acoustic wave device having a planar top surface thereon, said surface acoustic wave device capable of distorting said planar top surface thereon in response to an electrical signal; b) a reflective film disposed upon said planar top surface; and c) a beam-stop positioned to block radiation reflected from said planar top surface at a reflection angle greater than a critical range of angles.
Claim 18
Dependent Claim
39 words
Semiconductor lithography apparatus according to claim 15 wherein: the beam-stop is art aperture, an opening of which is positioned to pass radiation reflected from said planar top surface at a reflection angle only within said critical range of angles.
Claim 19
Dependent Claim
13 words
Semiconductor lithography apparatus according to claim 16, wherein: the reflective film is aluminum.
Claim 20
Dependent Claim
13 words
Semiconductor lithography apparatus according to claim 16, wherein: the reflective film is nickel.
Claim 21
Dependent Claim
48 words
The semiconductor lithography apparatus of claim 1 wherein said apparatus between said source and said wafer for causing gamma-radiation emission to pattern a layer of resist material applied to the surface of said wafer comprises a patterned image mask disposed between said gamma-radiation source and said semiconductor wafer.
Claim 22
Dependent Claim
48 words
Apparatus for semiconductor lithography comprising: a) a semiconductor wafer; b) a gamma-radiation source spaced from said semiconductor wafer and capable of emitting gamma-radiation emissions toward a surface of said semiconductor wafer; and c) a patterned mask disposed between said gamma-radiation source and said surface of said semiconductor wafer.
Claim 23
Dependent Claim
48 words
Apparatus for semiconductor lithography comprising: a) a semiconductor wafer; b) a gamma-radiation source spaced from said semiconductor wafer and capable of emitting gamma-radiation emissions toward a surface of said semiconductor wafer; and c) a patterned mask disposed between said gamma-radiation source and said surface of said semiconductor wafer.
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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) | 2000-01-07 | 2000-07-08 | 2001-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-01-07 | 2004-07-08 | 2005-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-01-07 | 2008-07-08 | 2009-01-07 | $7700.00 | Window Closed / Lapsed |