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US4084903A Expired / Lapsed US ⏱️ 0.0 years remaining

High-precision mask photorepeater

Assignee: Thales SA
•
Filing: 1976-10-26
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Granted: 1978-04-18
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Expires: 1996-10-26
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Abstract

Abstract A high-precision mask photorepeater projects the image of a mask upon a sample. The sample upon which an impression is to be made is a thin plate of semiconductor material with dimensions of the order of 10 centimeters. Each zone to be recorded is brought opposite the lens. A system of pneumatic sensors brings the center of the zone to be recorded into the correct plane and positions this zone in the focal plane of the lens.

Inventors

  • 👤 Georges Pircher

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 16:33
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/70; G03F7/70691; G03F7/707

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 119 words
A mask photorepeater apparatus comprising a light source for radiating a light beam, and upon said light beam trajectory, a mask, an optical system, a table having means for carrying a sample holder, said system being adapted for forming of said mask, upon said sample, an image with a magnification factor substantially lower than 1, motor means for displacing said table, and computer means, for controlling said motor means according a predetermined program, said carrying means comprising at least three piezoelectric bars having respective electric control inputs, pneumatic sensors tied to said optical system, for sensing the distance between said sample and the front of said optical means, and for delivering control signals to said inputs of said bars.
Claim 2
Dependent Claim 119 words
A mask photorepeater apparatus comprising a light source for radiating a light beam, and upon said light beam trajectory, a mask, an optical system, a table having means for carrying a sample holder, said system being adapted for forming of said mask, upon said sample, an image with a magnification factor substantially lower than 1, motor means for displacing said table, and computer means, for controlling said motor means according a predetermined program, said carrying means comprising at least three piezoelectric bars having respective electric control inputs, pneumatic sensors tied to said optical system, for sensing the distance between said sample and the front of said optical means, and for delivering control signals to said inputs of said bars.
Claim 3
Dependent Claim 51 words
An apparatus as claimed in claim 1, wherein said pneumatic sensors are of the differential type and comprise nozzles arranged in the vicinity of the front of said system, said nozzles being positioned at the top of a square contained in a plane perpendicular to the optical axis and centred thereon.
Claim 4
Dependent Claim 28 words
An apparatus as claimed in claim 1, wherein the neutral axis of the sample is made flat, means being provided for applying said sample to said sample holder.
Claim 5
Dependent Claim 25 words
An apparatus as claimed in claim 3, wherein said applying means comprise a pump, and pipes connected to said pump for creating a reduced pressure.
Claim 6
Dependent Claim 42 words
An apparatus as claimed in claim 1, wherein said sample specimen is a thin plate of the order of 10 centimeters of transverse dimensions made of a semiconductor material, and wherein said optical system has a magnification of the order of 1/10.

References Cited (Backward Citations)

US3632205A Cited
US3704946A Cited
US3704657A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-04-17 1981-10-17 1982-04-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-04-17 1985-10-17 1986-04-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-04-17 1989-10-17 1990-04-18 $7700.00 Window Closed / Lapsed

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