Patent US3806221A successfully refreshed from Google Patents.
US3806221A
Expired / Lapsed
US
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Holographic method of recording and reproducing etching masks
Assignee: Siemens AG
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Filing: 1971-11-16
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Granted: 1974-04-23
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Expires: 1991-11-16
Abstract
Abstract Substantially two-dimensional objects are holographically recorded and reproduced by directing a light beam of a spherical reference wave onto one side of a planar hologram carrier and directing the object wave upon the opposite side, the object being centered upon the normal which passes from the wave center of the reference wave onto the hologram carrier which is larger, preferably very much larger than the object. The hologram photographically recorded on the carrier is reproduced by directing toward the hologram carrier a spherical reproducing wave whose wave center location relative to the hologram carrier is coincident with that of the reference wave used for recording, but whose directional propagation is opposed to that of the reference wave.
Inventors
- 👤 H Kiemle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 10:37
CPC Classifications
G; G03; G03H; G03H1/00; G03H1/02; G03H1/024; G03H1/0248; Y; Y10; Y10S; Y10S359/00; Y10S359/90
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
265 words
The method of lens-free projection of an image of an integrated circuit etching mask of planar shape onto a semiconductor substrate coated with a photosensitive layer responsive to substantially only blue light comprising the steps of: forming a Lippmann-Bragg hologram of said etching mask by directing a spherical reference light wave, emanating from a wave center and having a wave length of substantially red light, onto one face of a photographic plate having two opposing planar faces, from one side thereof, said photographic plate having a larGer area than the area of said etching mask, and directing an object light wave having a wave length of substantially red light from said etching mask onto the other face of said photographic plate from the other side thereof, said etching mask being centered on a line perpendicular to the faces of said photographic plate and passing through said plate and the wave center of the spherical reference wave, said planar etching mask being oriented substantially parallel to said faces; uniformly shrinking said hologram during development of said photographic plate by an amount such that a distortion-free image may be reconstructed from said hologram with substantially blue light; and reconstructing a real image from the shrunken hologram on said substantially only blue photosensitive layer of said semiconductor substrate by directing toward the shrunken hologram a spherical reproducing light wave of substantially blue light having a wave center coinciding with the position of the wave center of the spherical reference wave relative to the photographic plate and having a direction of propagation opposite to that of the reference wave.
Claim 2
Independent Claim
265 words
The method of lens-free projection of an image of an integrated circuit etching mask of planar shape onto a semiconductor substrate coated with a photosensitive layer responsive to substantially only blue light comprising the steps of: forming a Lippmann-Bragg hologram of said etching mask by directing a spherical reference light wave, emanating from a wave center and having a wave length of substantially red light, onto one face of a photographic plate having two opposing planar faces, from one side thereof, said photographic plate having a larGer area than the area of said etching mask, and directing an object light wave having a wave length of substantially red light from said etching mask onto the other face of said photographic plate from the other side thereof, said etching mask being centered on a line perpendicular to the faces of said photographic plate and passing through said plate and the wave center of the spherical reference wave, said planar etching mask being oriented substantially parallel to said faces; uniformly shrinking said hologram during development of said photographic plate by an amount such that a distortion-free image may be reconstructed from said hologram with substantially blue light; and reconstructing a real image from the shrunken hologram on said substantially only blue photosensitive layer of said semiconductor substrate by directing toward the shrunken hologram a spherical reproducing light wave of substantially blue light having a wave center coinciding with the position of the wave center of the spherical reference wave relative to the photographic plate and having a direction of propagation opposite to that of the reference wave.
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) | 1977-04-22 | 1977-10-22 | 1978-04-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-22 | 1981-10-22 | 1982-04-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-22 | 1985-10-22 | 1986-04-23 | $7700.00 | Window Closed / Lapsed |