Improved step-and-repeat projection alignment and exposure system

Claim 2

Photometric printing apparatus comprising: a holder for holding a first object; a stage for holding a second object; a light source unit disposed for selectively illuminating different portions of the first object; a projection lens, disposed between the holder and the stage, for projecting an image of an illuminated portion of the first object onto the second object; and control means for moving the stage to print the image of the illuminated portion of the first object at different regions of the second object.

Claim 3

Photometric printing apparatus as in claim 1 including: first optical means, disposed between the projection lens and the holder, for providing a viewing port permitting viewing of an aerial image of a portion of the second object illuminated by the projected image of the illuminated portion of the first object; and second optical means disposed for viewing the aerial image: said control means being operable for moving the stage to align the illuminated portion of the second object with respect to the image of the illuminated portion of the first object.

Claim 4

Photometric printing apparatus as in claim 1 including: an additional stage for holding the holder; and control means for moving the additional stage to align the first object with respect to a predetermined frame of reference.

Claim 5

Photometric printing apparatus as in claim 3 wherein: the first-mentioned stage is movable along coordinate axes; and the predetermined frame of reference comprises at least one of the axes of motion of the first-mentioned stage.

Claim 6

Photometric printing apparatus as in claim 1 wherein the light source unit includes: a light source disposed for projecting light along an optical path to the first object; a shutter disposed for selectively controlling the passage of light along the optical path to the first object; and a plurality of different mask plates disposed for selectively controlling the portions of the first object illuminated by light passing along the optical path to the first object when the shutter is opened.

Claim 7

Photometric printing apparatus as in claim 5 wherein: the light source projects exposure light for both illuminating and exposing a photosensitive film on the second object and illumination light for illuminating without exposing the photosensitive film on the second object along the optical path; and the apparatus includes a pair of filters disposed for selectively controlling whether exposure or illumination light passes along the optical path to the first object.

Claim 8

Photometric printing apparatus as in claim 1 wherein: the holder comprises a vacuum holder for holding a first object comprising a reticle; the stage comprises a main stage for holding a second object comprising a semiconductive wafer; the projection lens comprises a projection lens of the reduction type; the light source unit comprises a source of light, a shutter, and a plurality of mask plates for selectively illuminating different portions of the reticle when the shutter is opened; and the control means is operable for moving the main stage along orthogonal X and Y axes to print the image of the illuminated portion of the reticle at different regions of the semiconductive wafer.

Claim 9

Photometric printing apparatus as in claim 7 including: an optical device, disposed between the projection lens and the vacuum holder, for providing a viewing port permitting viewing of an aerial image of a portion of the semiconductive wafer illuminated by the projected image of the illuminated portion of the reticle; and a first objective lens unit operable with a binocular lens unit for viewing the aerial image; said control means comprising first control means for moving the main stage to align the illuminated portion of the semi- conductive wafer with respect to the image of the illuminated portion of the reticle.

Claim 10

Photometric printing apparatus as in claim 8 including: an additional stage for holding the vacuum holder; and second control means for moving the additional stage along the X and Y axes and about an orthogonal Z axis to align the reticle with respect to one of the axes of motion of the main stage.

Claim 11

1Q. Photometric printing apparatus as in claim 9 including: a pair of prealignment reticles aligned with respect to said one of the axes of motion of the main stage; a light source disposed for illuminating the prealignment reticles; a vacuum chuck, rotatably supported on the main stage, for holding the semiconductive wafer, said first control means being operable for moving the main stage along the orthogonal X and Y axes to locate the semiconductive wafer in a prealignment position beneath the prealignment reticles; a second objective lens unit, disposed between the prealignment reticles and the main stage, for projecting images of the illuminated prealignment reticles onto the semiconductive wafer when it is located in the prealignment position, the second objective lens unit being operable with the ocular lens unit for viewing an aerial image of a pair of alignment marks disposed along opposite sides of the semiconductive wafer and illuminated by the projected images of the prealignment reticles; and third control means operable with the first control means for rotating the vacuum chuck and moving the main stage to align the illuminated alignment marks on the semi- conductive wafer with the projected images of the prealignment reticles.

Claim 12

Alignment apparatus comprising: a holder for holding a first object; a stage for holding a second object, said stage being movable along coordinate axes to position the second object with respect to the first object; and means for aligning an indicium with one of the axes of motion of the stage.

Claim 13

Alignment apparatus comprising: a holder for holding a first object; a stage for holding a second object, said stage being movable along coordinate axes to position the second object with respect to the first object; and means for aligning an indicium with one of the axes of motion of the stage.

Claim 14

Alignment apparatus as in claim 11 wherein said means comprises a substage mounted on the stage and provided with adjustment means for positioning the indicium in a plane parallel to a plane of the stage and for positioning the indicium in alignment with said one of the axes of motion of the stage.

Claim 15

Alignment apparatus as in claim 12 including: control means for moving the holder to position the first object with respect to the indicium; and optical means for viewing the indicium and the first object.

Claim 16

Alignment apparatus as in claim 13 wherein; said indicium comprises a reference mark disposed on the substage and visible through the optical means; and said adjustment means comprises a first adjustment screw for adjusting the substage to position the reference mark in a plane parallel to an image plane of the optical means and a second adjustment screw for adjusting the substage to position the reference mark in alignment with said one of the axes of motion of the stage.

Claim 17

It is respectfully requested to delete the following cross-references in the specification at the earliest time allowable: page 8, end of line 25 : insert period. page 8, line 26 through page 9, line 1 "application": delete. page 9, line 1 : replace "main" by "Main". page 19, line 8 after "Figure 2" through line 12 "herein":delete. page 19, line 27 after "mounted" through line 28 "015,737.": delete. page 55, line 14, after "circuits" through line 15 "and": delete. page 56, line 18 "control" through line 19 "015,713" :delete.

Claim 18

It is respectfully requested to delete the following cross-references in the specification at the earliest time allowable: page 8, end of line 25 : insert period. page 8, line 26 through page 9, line 1 "application": delete. page 9, line 1 : replace "main" by "Main". page 19, line 8 after "Figure 2" through line 12 "herein":delete. page 19, line 27 after "mounted" through line 28 "015,737.": delete. page 55, line 14, after "circuits" through line 15 "and": delete. page 56, line 18 "control" through line 19 "015,713" :delete.