Patent US5617211A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5617211A Expired / Lapsed US ⏱️ 0.0 years remaining

Exposure apparatus

Assignee: Nikon Corp
•
Filing: 1995-08-16
•
Granted: 1997-04-01
•
Expires: 2015-08-16
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract This invention relates to an exposure apparatus for synchronously scanning a mask and a photosensitive substrate with respect to a plurality of projection optical systems, thereby properly transferring an entire pattern area on the mask onto the photosensitive substrate. A plurality of sets of mask-side reference marks and substrate-side reference marks are arranged at positions corresponding to each other on the mask surface and the photosensitive substrate surface and at least at two positions conjugate with the plurality of projection optical systems. The displacement amount between an image of a mask-side reference mark or a substrate-side reference mark formed on the corresponding substrate-side reference mark or mask-side reference mark through the projection optical system and the position of the substrate-side reference mark and the mask-side reference mark is measured. The imaging characteristics of the plurality of projection optical systems are corrected in accordance with the displacement amount.

Inventors

  • 👤 Kei Nara
  • 👤 Toshio Matsuura
  • 👤 Muneyasu Yokota
  • 👤 Yukio Kakizaki
  • 👤 Yoshio Fukami
  • 👤 Seiji Miyazaki
  • 👤 Tsuyoshi Narabe

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 20:28
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/70; G03F7/70216; G03F7/70241; G03F7/20; G03F7/70275; G03F7/70358; G03F9/00; G03F9/70

Claims Analysis

Total Claims: 23
Claim 1
Independent Claim 178 words
An exposure apparatus comprising: an illumination optical system for illuminating a plurality of partial areas of a mask; a plurality of projection optical systems for projecting images onto a photosensitive substrate, the light beam passing through each of said partial areas of said mask being partially overlapping; a scanning mechanism for synchronously scanning said mask and said photosensitive substrate with respect to said projection optical systems in a predetermined direction; mask reference marks arranged on a surface corresponding to said mask surface; substrate reference marks arranged on a surface corresponding to said photosensitive substrate surface according to said mask reference marks; a displacement amount measurement unit for measuring a displacement between an image of one of said mask reference mark and said substrate reference mark, which image is formed through said projection optical system, and the other of said mask reference mark and said substrate reference mark; and a lens adjustment mechanism for correcting imaging characteristics of at least one of said projection optical system in accordance with the displacement amount measured by said displacement amount measurement unit.
Claim 2
Dependent Claim 178 words
An exposure apparatus comprising: an illumination optical system for illuminating a plurality of partial areas of a mask; a plurality of projection optical systems for projecting images onto a photosensitive substrate, the light beam passing through each of said partial areas of said mask being partially overlapping; a scanning mechanism for synchronously scanning said mask and said photosensitive substrate with respect to said projection optical systems in a predetermined direction; mask reference marks arranged on a surface corresponding to said mask surface; substrate reference marks arranged on a surface corresponding to said photosensitive substrate surface according to said mask reference marks; a displacement amount measurement unit for measuring a displacement between an image of one of said mask reference mark and said substrate reference mark, which image is formed through said projection optical system, and the other of said mask reference mark and said substrate reference mark; and a lens adjustment mechanism for correcting imaging characteristics of at least one of said projection optical system in accordance with the displacement amount measured by said displacement amount measurement unit.
Claim 3
Dependent Claim 45 words
An apparatus according to claim 1, wherein the image of said mask reference mark is projected near said substrate reference mark, and said displacement amount measurement unit measures the displacement amount between the position of said image and the position of said substrate reference mark.
Claim 4
Dependent Claim 45 words
An apparatus according to claim 1, wherein the image of said substrate reference mark is projected near said mask reference mark, and said displacement amount measurement unit measures the displacement amount between the position of said image and the position of said mask reference mark.
Claim 5
Dependent Claim 29 words
An apparatus according to claim 1, wherein said plurality of mask reference marks and said plurality of substrate reference marks are arranged on a block having a sufficient rigidity.
Claim 6
Dependent Claim 97 words
An apparatus according to claim 1, wherein correction values for adjusting at least one of projection magnifications of said projection optical systems, and rotations and shifts of the projected images through said projection optical systems are obtained based on the displacement amount measured by said displacement amount measurement unit, said correction values minimizing distortions in the projected images, and wherein said lens adjustment mechanism changes the imaging characteristics of said projection optical systems by changing at least one of the magnifications of said plurality of projection optical systems, and the rotations and shifts of the projected images.
Claim 7
Dependent Claim 36 words
An apparatus according to claim 1, wherein said mask reference marks are arranged in areas images of which are overlapping each other, and wherein said substrate reference marks are arranged in image areas overlapping each other.
Claim 8
Dependent Claim 28 words
An apparatus according to claim 6, wherein the displacement amount at the overlapping positions of said plurality of projection optical systems is measured using the same reference mark.
Claim 9
Dependent Claim 82 words
An apparatus according to claim 1, wherein said mask reference marks comprise mask first reference marks and mask second reference marks, and said substrate reference marks comprise substrate first reference marks and substrate second reference marks, said mask first reference marks and said substrate first reference marks are arranged at positions corresponding to said projection optical systems arranged at both ends, and one of said mask first reference mark and said mask second reference mark is fixed and the other is movable.
Claim 10
Dependent Claim 42 words
An apparatus according to claim 8, wherein said mask first reference marks and said substrate first reference marks are arranged on a block having a sufficient rigidity, and said mask second reference marks are formed on a mask stage supporting said mask.
Claim 11
Dependent Claim 121 words
An exposure method for exposing a photosensitive substrate by a plurality of projection optical systems, a plurality of light beams passing through a plurality of partial areas of a mask being partially overlapping, comprising: a step of measuring a displacement between an image of one of a mask reference mark formed on a surface corresponding to said mask surface according to the overlapping part of said light beams and a substrate reference mark formed on a surface corresponding to said photosensitive substrate surface according to the overlapping part of said light beams, which image is formed through said projection optical system, and the other of said mask reference mark and said substrate reference mark; and a step of correcting said displacement.
Claim 12
Dependent Claim 121 words
An exposure method for exposing a photosensitive substrate by a plurality of projection optical systems, a plurality of light beams passing through a plurality of partial areas of a mask being partially overlapping, comprising: a step of measuring a displacement between an image of one of a mask reference mark formed on a surface corresponding to said mask surface according to the overlapping part of said light beams and a substrate reference mark formed on a surface corresponding to said photosensitive substrate surface according to the overlapping part of said light beams, which image is formed through said projection optical system, and the other of said mask reference mark and said substrate reference mark; and a step of correcting said displacement.
Claim 13
Dependent Claim 29 words
An exposure method according to claim 10, wherein an imaging characteristics of at least one of said plurality of projection optical systems is corrected in said step of correcting.
Claim 14
Dependent Claim 30 words
An exposure method according to claim 11, wherein said correcting of said imaging characteristics includes at least one of a projection magnification correction, a shifting correction and a rotation correction.
Claim 15
Dependent Claim 223 words
An exposure method for exposing a photosensitive substrate by a plurality of projection optical systems, a plurality of light beams passing through a plurality of partial areas of a mask being partially overlapping, comprising: a step of measuring a first displacement between an image of one of a first mask reference mark formed on a surface corresponding to said mask surface according to the overlapping part of said light beams and a first substrate reference mark formed on a surface corresponding to said photosensitive substrate surface according to the overlapping part of said light beams, which image is formed through said projection optical system, and the other of said first mask reference mark and said first substrate reference mark; a step of correcting said first displacement; a step of measuring a second displacement between an image of one of a second mask reference mark formed on a surface corresponding to said mask surface and at a position different from said first mask reference mark and a second substrate reference mark formed on a surface corresponding to said photosensitive substrate surface and at a position different from said first substrate reference mark, which image is formed through said projection optical system, and the other of said second mask reference mark and said second substrate reference mark; and a step of correcting said second displacement.
Claim 16
Dependent Claim 223 words
An exposure method for exposing a photosensitive substrate by a plurality of projection optical systems, a plurality of light beams passing through a plurality of partial areas of a mask being partially overlapping, comprising: a step of measuring a first displacement between an image of one of a first mask reference mark formed on a surface corresponding to said mask surface according to the overlapping part of said light beams and a first substrate reference mark formed on a surface corresponding to said photosensitive substrate surface according to the overlapping part of said light beams, which image is formed through said projection optical system, and the other of said first mask reference mark and said first substrate reference mark; a step of correcting said first displacement; a step of measuring a second displacement between an image of one of a second mask reference mark formed on a surface corresponding to said mask surface and at a position different from said first mask reference mark and a second substrate reference mark formed on a surface corresponding to said photosensitive substrate surface and at a position different from said first substrate reference mark, which image is formed through said projection optical system, and the other of said second mask reference mark and said second substrate reference mark; and a step of correcting said second displacement.
Claim 17
Dependent Claim 48 words
An exposure method according to claim 13, wherein an imaging characteristics of at least one of said plurality of projection optical systems is corrected in said step of correcting said first displacement, and the position of said mask is corrected in said step of correcting said second displacement.
Claim 18
Dependent Claim 166 words
An exposure apparatus comprising: an illumination optical system for illuminating a plurality of partial areas of a mask; a plurality of projection optical systems for projecting images onto a photosensitive substrate, the light beam passing through each of said partial areas of said mask being partially overlapping; a scanning mechanism for synchronously scanning said mask and said photosensitive substrate with respect to said projection optical systems in a predetermined direction; a block having a mask reference mark arranged on a surface corresponding to said mask surface according to the overlapping part of said light beam and a substrate reference mark arranged on a surface corresponding to said photosensitive substrate surface according to the overlapping part of said light beam; and a displacement amount measurement unit for measuring a displacement between an image of one of said mask reference mark and said substrate reference mark, which image is formed through said projection optical system, and the other of said mask reference mark and said substrate reference mark.
Claim 19
Dependent Claim 166 words
An exposure apparatus comprising: an illumination optical system for illuminating a plurality of partial areas of a mask; a plurality of projection optical systems for projecting images onto a photosensitive substrate, the light beam passing through each of said partial areas of said mask being partially overlapping; a scanning mechanism for synchronously scanning said mask and said photosensitive substrate with respect to said projection optical systems in a predetermined direction; a block having a mask reference mark arranged on a surface corresponding to said mask surface according to the overlapping part of said light beam and a substrate reference mark arranged on a surface corresponding to said photosensitive substrate surface according to the overlapping part of said light beam; and a displacement amount measurement unit for measuring a displacement between an image of one of said mask reference mark and said substrate reference mark, which image is formed through said projection optical system, and the other of said mask reference mark and said substrate reference mark.
Claim 20
Dependent Claim 51 words
An apparatus according to claim 15, wherein said plurality of projection optical system comprise a first group of projection optical systems arranged in a first direction and a second group of projection optical systems arranged apart from said first group by a predetermined space and substantially parallel to said first direction.
Claim 21
Dependent Claim 24 words
An apparatus according to claim 15, wherein the size of said mask reference mark is different from the size of said substrate reference mark.
Claim 22
Dependent Claim 51 words
An apparatus according to claim 1, wherein said plurality of projection optical systems comprise a first group of projection optical systems arranged in a first direction and a second group of projection optical systems arranged apart from the first group by a predetermined space and substantially parallel to said first direction.
Claim 23
Dependent Claim 24 words
An apparatus according to claim 1, wherein the size of said mask reference mark is different from the size of said substrate reference mark.

References Cited (Backward Citations)

US3943359A Cited
US4103998A Cited
US4269505A Cited
US4629313A Cited
US4723221A Cited
US4801808A Cited
US4655600A Cited
US4801208A Cited
US5237393A Cited
US5044750A Cited
US5296917A Cited
US5444538A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2000-03-31 2000-09-30 2001-04-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2004-03-31 2004-09-30 2005-04-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2008-03-31 2008-09-30 2009-04-01 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag