US5028797A
Expired / Lapsed
US
⏱️ 0.0 years remaining
An alignment system for align first and second objects using alignment marks
Assignee: Canon Inc
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Filing: 1989-09-28
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Granted: 1991-07-02
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Expires: 2009-09-28
Abstract
Abstract An alignment system for aligning a mask and a wafer into a predetermined positional relationship uses alignment marks provided on the mask and the water. In this system, light from a light source is directed to the alignment marks of the mask and the wafer and, then, the light from these alignment marks is detected by an accumulation type photoelectric converting device, for alignment of the mask and the wafer. The accumulation time of the photoelectric converting device is controlled to be sufficiently longer than or to be equal to a multiple, by an integral number, of the period of relative and natural vibration of the mask and the wafer. This makes it possible to reduce the effect of the relative vibration of the mask and the wafer upon the alignment result and, therefore, makes it possible to enhance the alignment precision.
Inventors
- 👤 Naoto Abe
- 👤 Shigeyuki Suda
- 👤 Koji Uda
- 👤 Hirohisa Ohta
- 👤 Noriyuki Nose
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 17:25
CPC Classifications
G; G03; G03F; G03F9/00; G03F9/70; G03F9/7096; G03F9/7049
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
114 words
An alignment system for aligning first and second objects by using alignment marks, said system comprising: a light source; an accumulation type photoelectric converting device; an optical arrangement for directing light from said light source to the alignment marks and then to said accumulating type photoelectric converting device; detecting means for detecting the period of the natural vibration frequency with respect to the relative vibration of the first and second objects; and control means for controlling the accumulation time of said accumulation type photoelectric converting device on the basis of the detection by said detecting means, so that the controlled accumulation time of said accumulation type photoelectric converting device is longer than said period.
Claim 2
Dependent Claim
114 words
An alignment system for aligning first and second objects by using alignment marks, said system comprising: a light source; an accumulation type photoelectric converting device; an optical arrangement for directing light from said light source to the alignment marks and then to said accumulating type photoelectric converting device; detecting means for detecting the period of the natural vibration frequency with respect to the relative vibration of the first and second objects; and control means for controlling the accumulation time of said accumulation type photoelectric converting device on the basis of the detection by said detecting means, so that the controlled accumulation time of said accumulation type photoelectric converting device is longer than said period.
Claim 3
Dependent Claim
26 words
A system according to claim 1, wherein the controlled accumulation time of said photoelectric converting device is equal to a positive integer multiple of said period.
Claim 4
Dependent Claim
31 words
A system according to claim 2, wherein the controlled accumulation time of said photoelectric converting device is equal to a multiple, by an integer not less than 4, of said period.
Claim 5
Dependent Claim
107 words
An alignment system for aligning first and second objects by using alignment marks, said system comprising: a light source; an accumulation type photoelectric converting device; an optical arrangement for directing light from said light source to the alignment marks and then to said photoelectric converting device; and control means operable to store the period of the natural vibration frequency with respect to the relative vibration of the first and second objects and for determining and controlling the accumulation time of said photoelectric converting device on the basis of said memorized period, so that the controlled accumulation time of said photoelectric converting device is longer than said period.
Claim 6
Dependent Claim
107 words
An alignment system for aligning first and second objects by using alignment marks, said system comprising: a light source; an accumulation type photoelectric converting device; an optical arrangement for directing light from said light source to the alignment marks and then to said photoelectric converting device; and control means operable to store the period of the natural vibration frequency with respect to the relative vibration of the first and second objects and for determining and controlling the accumulation time of said photoelectric converting device on the basis of said memorized period, so that the controlled accumulation time of said photoelectric converting device is longer than said period.
Claim 7
Dependent Claim
26 words
A system according to claim 4, wherein the controlled accumulation time of said photoelectric converting device is equal to a positive integer multiple of said period.
Claim 8
Dependent Claim
31 words
A system according to claim 4, wherein the controlled accumulation time of said photoelectric converting device is equal to a multiple, by an integer not less than 4, of said period.
Claim 9
Dependent Claim
111 words
An alignment system for aligning first and second objects by using alignment marks, said system comprising: a light source; an accumulation type photoelectric converting device; an optical arrangement for directing light from said light source to the alignment marks and then to said photoelectric converting device; detecting means for detecting the period of the natural vibration frequency with respect to the relative vibration of the first and second objects; and control means for controlling the accumulation time of said photoelectric converting device on the basis of detection by said detecting means, so that the controlled accumulation time of said photoelectric converting device is equal to an integer multiple of said period.
Claim 10
Dependent Claim
111 words
An alignment system for aligning first and second objects by using alignment marks, said system comprising: a light source; an accumulation type photoelectric converting device; an optical arrangement for directing light from said light source to the alignment marks and then to said photoelectric converting device; detecting means for detecting the period of the natural vibration frequency with respect to the relative vibration of the first and second objects; and control means for controlling the accumulation time of said photoelectric converting device on the basis of detection by said detecting means, so that the controlled accumulation time of said photoelectric converting device is equal to an integer multiple of said period.
Claim 11
Dependent Claim
31 words
A system according to claim 7, wherein the controlled accumulation time of said photoelectric converting device is equal to a multiple, by an integer not less than 4, of said period.
Claim 12
Dependent Claim
111 words
An alignment system for aligning first and second objects by using alignment marks, said system comprising: a light source; an accumulation type photoelectric converting device; an optical arrangement for directing light from said light source to the alignment marks and then to said photoelectric converting device; and control means operable to store the period of the natural vibration frequency with respect to the relative vibration of the first and second objects and to determine and control the accumulation time of said photoelectric converting device on the basis of said memorized period, so that the controlled accumulation time of said photoelectric converting device is equal to an integer multiple of said period.
Claim 13
Dependent Claim
111 words
An alignment system for aligning first and second objects by using alignment marks, said system comprising: a light source; an accumulation type photoelectric converting device; an optical arrangement for directing light from said light source to the alignment marks and then to said photoelectric converting device; and control means operable to store the period of the natural vibration frequency with respect to the relative vibration of the first and second objects and to determine and control the accumulation time of said photoelectric converting device on the basis of said memorized period, so that the controlled accumulation time of said photoelectric converting device is equal to an integer multiple of said period.
Claim 14
Dependent Claim
31 words
A system according to claim 9, wherein the controlled accumulation time of said photoelectric converting device is equal to a multiple, by an integer not less than 4, of said period.
Claim 15
Independent Claim
139 words
A method of aligning first and second objects by use of alignment marks, said method comprising the steps of: detecting the period of the natural vibration frequency with respect to the relative vibration of the first and second objects; preparing and storing data related to the detected period; determining, by using the stored data, the accumulation time of an accumulation type photoelectric converting device which is operable to photoelectrically convert light from the alignment marks illuminated by a light source, into an electrical signal, wherein the determined accumulation time if longer than the detected period; setting the optical output of the light source in accordance with the determined accumulation time; effecting the accumulation of photoelectrically converted signals of the photoelectric converting device, with the determined accumulation time; and aligning the first and second objects by using the accumulated signals.
Claim 16
Independent Claim
139 words
A method of aligning first and second objects by use of alignment marks, said method comprising the steps of: detecting the period of the natural vibration frequency with respect to the relative vibration of the first and second objects; preparing and storing data related to the detected period; determining, by using the stored data, the accumulation time of an accumulation type photoelectric converting device which is operable to photoelectrically convert light from the alignment marks illuminated by a light source, into an electrical signal, wherein the determined accumulation time if longer than the detected period; setting the optical output of the light source in accordance with the determined accumulation time; effecting the accumulation of photoelectrically converted signals of the photoelectric converting device, with the determined accumulation time; and aligning the first and second objects by using the accumulated signals.
Claim 17
Dependent Claim
23 words
A method according to claim 11, wherein the set accumulation time is equal to a multiple, by an integer, of the detected period.
Claim 18
Dependent Claim
27 words
A method according to claim 11, wherein the set accumulation time is equal to a multiple, by a number not less than 4, of the detected period.
Claim 19
Dependent Claim
36 words
A method according to claim 11, wherein the optical output of the light source is set so that the product of the optical output of the light source with the accumulation time is maintained substantially constant.
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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) | 1994-07-01 | 1994-12-31 | 1995-07-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-07-01 | 1998-12-31 | 1999-07-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-07-01 | 2002-12-31 | 2003-07-02 | $7700.00 | Window Closed / Lapsed |