Pattern printing including aligning masks and monitoring such alignment
AssigneeBell Telephone Laboratories, Incorporated
InventorsRobert J. Hart, Ralph C. Joseph
Life of this patent
Estimating the term…
Abstract
A circuit pattern printing system includes alignment apparatus (71) which is located remote from a printer (35). The alignment apparatus includes a means for displaying a cursor (69) on a video screen (101). The cursor identifies a desired position of a fiducial mark (61) printed on a substrate (106) when the substrate is positioned against a reference guide (86) on an alignment table (76). The cursor (69) and the reference guide (86) are aligned to each other by first aligning the reference guide (86) to an alignment marker on a standards substrate (41), and then aligning the cursor to a fiducial mark located on the same standards substrate.
Claims3
A method of adjusting a printing mask mounted in a visually inaccessible location of a printing apparatus relative to a first substrate holder having a first reference guide oriented in the direction of a reference axis of said first substrate holder, such that a pattern on the printing mask, including alignment marks, becomes located coincident with a predetermined position on a substrate when such substrate is placed against said first reference guide on said first substrate holder, the method comprising:
- positioning a standard having at least one reference edge and having alignment features thereon located at predetermined distances from said at least one reference edge on a second substrate holder and with said at least one reference edge of said standard against a second guide located on said second substrate holder and oriented in the direction of a second reference axis, said alignment features including at least one set of fiducial marks which corresponds to the predetermined position of the alignment marks on the substrate;
- manipulating the second substrate holder relative to two spaced fields of view of a viewing screen of an imaging system to directionally align the second reference axis with a centerline through said spaced fields of view;
- generating cursor marks on said viewing screen, said cursor marks corresponding to the alignment marks of the pattern on said printing mask;
- translating the second substrate holder with said standard thereon relative to the fields of view of said screen and said cursor marks on said screen to align the cursor marks and said at least one set of fiducial marks to each other;
- placing a substrate against said first reference guide in said printing apparatus;
- printing the pattern including the alignment marks of the printing mask onto the substrate;
- positioning the substrate with the printed pattern in place of the standard on the second substrate holder;
- comparing the position of an image of the printed alignment marks to the position of the cursor marks to determine a deviation of the printed alignment marks from the predetermined position on the substrate;
- and
- adjusting the position of the mask to correct any such deviation.
Dependencies are inferred from the claim text.