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Inspection method and apparatus for a mask pattern used in semiconductor device fabrication

Assignee: Fujitsu Ltd
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Filing: 1984-09-10
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Granted: 1987-02-03
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Expires: 2004-09-10
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Abstract

Abstract An inspection method and apparatus for a mask pattern such as a reticle pattern used in the fabrication of a semiconductor device is disclosed. The mask pattern is inspected by an imaging sensor mounted on a stage on which a fabricated object is also mounted. The imaging sensor converts an optical image of the mask pattern which is intended to be exposed on the object to a video signal and it is inspected by comparing it with another video signal provided from data for designing the mask pattern. This inspection is made before the process of exposing the mask pattern on the fabricated object in order to avoid a waste of time in the semiconductor pattern process.

Inventors

  • 👤 Kenichi Kobayashi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 23:09
CPC Classifications
G; G03; G03F; G03F1/00; G03F1/68; G03F1/82; G03F1/84; G03F7/00; G03F7/70; G03F7/70483; G03F7/70591; H; H10; H10P; H10P95/00

Claims Analysis

Total Claims: 27
Claim 1
Independent Claim 102 words
An inspection method for a mask pattern used in semiconductor fabrication which uses an optical system for exposing said mask pattern on a fabricated object and printing said mask pattern; thereon, the inspection method comprising the steps of: projecting an optical image of said mask pattern onto an image sensor provided on a stage having said fabricated object mounted thereon; converting said optical image into a sensor video signal; generating a data video signal from design data used in fabricating said mask pattern, and comparing said sensor video signal to said data video signal for determining whether said mask pattern is normal.
Claim 2
Dependent Claim 102 words
An inspection method for a mask pattern used in semiconductor fabrication which uses an optical system for exposing said mask pattern on a fabricated object and printing said mask pattern; thereon, the inspection method comprising the steps of: projecting an optical image of said mask pattern onto an image sensor provided on a stage having said fabricated object mounted thereon; converting said optical image into a sensor video signal; generating a data video signal from design data used in fabricating said mask pattern, and comparing said sensor video signal to said data video signal for determining whether said mask pattern is normal.
Claim 3
Dependent Claim 44 words
The inspection method according to claim 1, wherein said steps are performed prior to exposing said mask pattern onto said fabricated object and wherein exposing said mask pattern onto said fabricated object is performed after said mask pattern has been determined to be normal.
Claim 4
Dependent Claim 137 words
An inspection apparatus for a mask pattern used in semiconductor fabrication, said apparatus comprising: an optical system for exposing said mask pattern on a fabricating object; an image sensor means for receiving an optical image of said mask pattern and for converting said optical image to a sensor video signal; data generating means for generating a data video signal from design data used in fabricating said mask pattern; and comparator means, coupled to said image sensor means and said data generating means, for comparing the output of said image sensor means to the output of said data generating means, said comparator means providing an indication of the difference therebetween; wherein said optical system comprises a single optical system for reducing and projecting said optical image of said mask pattern on a fabricated object and said image sensor.
Claim 5
Dependent Claim 137 words
An inspection apparatus for a mask pattern used in semiconductor fabrication, said apparatus comprising: an optical system for exposing said mask pattern on a fabricating object; an image sensor means for receiving an optical image of said mask pattern and for converting said optical image to a sensor video signal; data generating means for generating a data video signal from design data used in fabricating said mask pattern; and comparator means, coupled to said image sensor means and said data generating means, for comparing the output of said image sensor means to the output of said data generating means, said comparator means providing an indication of the difference therebetween; wherein said optical system comprises a single optical system for reducing and projecting said optical image of said mask pattern on a fabricated object and said image sensor.
Claim 6
Dependent Claim 18 words
The inspection apparatus according to claim 3, wherein said mask pattern comprises a mask pattern on a reticle.
Claim 7
Dependent Claim 15 words
The inspection apparatus according to claim 3, wherein said mask pattern comprises a single pattern.
Claim 8
Dependent Claim 20 words
The inspection apparatus according to claim 5, wherein said a single mask pattern comprises the mask pattern on a reticle.
Claim 9
Dependent Claim 23 words
The inspection apparatus according to claim 3, wherein said mask pattern comprises a plurality of patterns each having the same shape and size.
Claim 10
Dependent Claim 20 words
The inspection apparatus according to claim 7, wherein said plurality of mask patterns comprise the reticle patterns on a reticle.
Claim 11
Dependent Claim 15 words
The inspection apparatus according to claim 3, wherein said fabricated object comprises a semiconductor wafer.
Claim 12
Dependent Claim 14 words
The inspection apparatus according to claim 3, wherein said fabricated object comprises a photomask.
Claim 13
Dependent Claim 46 words
The inspection apparatus according to claim 3, wherein said image sensor means comprises a two-dimensional image sensor having a plurality of sensor elements arranged in an image plane, said image sensor means simultaneously converting said optical image of said mask pattern to said sensor video signal.
Claim 14
Dependent Claim 72 words
The inspection apparatus according to claim 3, wherein said image sensor means comprises a one-dimensional image sensor having a plurality of sensor elements arranged in a line parallel to one side of said optical image of said mask pattern, said image sensor means mechanically scanning said optical image in a direction perpendicular to the line of sensor arrangement, and converting said optical image of said mask pattern to said sensor video signal.
Claim 15
Dependent Claim 46 words
An inspection apparatus as set forth in claim 3, further including first memory means for storing said sensor video signal and second memory means for storing said data video signal, wherein the outputs of said first and second memory means are combined in said comparator means.
Claim 16
Independent Claim 157 words
An apparatus for inspection of a mask pattern and the fabrication of a semiconductor device, said apparatus comprising: an image sensor means for receiving an optical image of said mask pattern and for converting said optical image to a sensor video signal; data generating means for generating a data video signal from data design data used in fabricating said mask pattern; comparator means, coupled to said image sensor means and said data generating means, for comparing the output of said image sensor means to the output of said data generating means, said comparator means providing an indication of the difference therebetween, said difference being indicative of a defect in said mask pattern; and optical system means for first exposing said mask pattern on said image sensor means and then on an object to be fabricated whereby defects in said mask pattern are determined prior to the exposure of said mask pattern on the object to be fabricated.
Claim 17
Independent Claim 157 words
An apparatus for inspection of a mask pattern and the fabrication of a semiconductor device, said apparatus comprising: an image sensor means for receiving an optical image of said mask pattern and for converting said optical image to a sensor video signal; data generating means for generating a data video signal from data design data used in fabricating said mask pattern; comparator means, coupled to said image sensor means and said data generating means, for comparing the output of said image sensor means to the output of said data generating means, said comparator means providing an indication of the difference therebetween, said difference being indicative of a defect in said mask pattern; and optical system means for first exposing said mask pattern on said image sensor means and then on an object to be fabricated whereby defects in said mask pattern are determined prior to the exposure of said mask pattern on the object to be fabricated.
Claim 18
Dependent Claim 17 words
The apparatus according to claim 14, wherein said mask pattern comprises a mask pattern on a reticle.
Claim 19
Dependent Claim 14 words
The apparatus according to claim 14, wherein said mask pattern comprises a single pattern.
Claim 20
Dependent Claim 18 words
The apparatus according to claim 16, wherein said single mask pattern comprises the mask pattern on a reticle.
Claim 21
Dependent Claim 22 words
The apparatus according to claim 14, wherein said mask pattern comprises a plurality of patterns each having the same shape and size.
Claim 22
Dependent Claim 19 words
The apparatus according to claim 18, wherein said plurality of mask patterns comprise the reticle patterns on a reticle.
Claim 23
Dependent Claim 14 words
The apparatus according to claim 14, wherein said fabricated object comprises a semiconductor wafer.
Claim 24
Dependent Claim 13 words
The apparatus according to claim 14, wherein said fabricated object comprises a photomask.
Claim 25
Dependent Claim 45 words
The apparatus according to claim 14, wherein said image sensor means comprises a two-dimensional image sensor having a plurality of sensor elements arranged in an image plane, said image sensor means simultaneously converting said optical image of said mask pattern to said sensor video signal.
Claim 26
Dependent Claim 71 words
The apparatus according to claim 14, wherein said image sensor means comprises a one-dimensional image sensor having a plurality of sensor elements arranged in a line parallel to one side of said optical image of said mask pattern, said image sensor means mechanically scanning said optical image in a direction perpendicular to the line of sensor arrangement, and converting said optical image of said mask pattern to said sensor video signal.
Claim 27
Dependent Claim 45 words
An apparatus as set forth in claim 14, further including first memory means for storing said sensor video signal and second memory means for storing said data video signal, wherein the outputs of said first and second memory means are combined in said comparator means.

References Cited (Backward Citations)

US4472738A Cited
US4542404A Cited
US4532650A Cited
US4555798A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-02-02 1990-08-04 1991-02-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-02-02 1994-08-04 1995-02-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-02-02 1998-08-04 1999-02-03 $7700.00 Window Closed / Lapsed

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