Western Electric Company, Inc.

At&t Technologies, Inc.

Bruce E Truax

Laurence Shrapnell Watkins

Edward L Banks

Jerry D Breecher

A narrow beam of light (26) is directed at a beamsplitter (12) at an incident angle (.theta.) thereto. A portion (28) of the beam (26) passes through the beamsplitter (12) and is reflected from a first mirror (22) while a portion (29) of the beam (26) is reflected from the beamsplitter (12) and directed onto and reflected by a second mirror (24). The beams (28, 29) reflected from the first and second mirrors (22, 24) intersect at a reference plane (R). The incident angle .theta. of the light beam (26) is then varied until the reflected beams intersect on the surface of an object (32) along the plane of symmetry of the system. The known variation of the incident angle, .DELTA..theta., provides sufficient information to determine the distance of the surface of the object (32) from the reference plane (R). The object 32 is then moved in an incremental fashion and .DELTA..theta. determined for each step to ascertain the surface profile of the object.

Surface profiling technique

A photomask (30) used to form patterns on a resist coated semiconductor wafer is comprised of a transparent baseplate (31) having a thin metallic pattern (32) thereon; a transparent, planar coverplate (33) in intimate contact with the patterned baseplate (31) and an index matching fluid (34) interposed therebetween.

Methods of fabricating a photomask

Photomask and method of using same

A plurality of retroreflector devices (22-23) are fixedly mounted in spaced relation on a microwave tower (10) are raster scanned with a laser beam (46). The direction of the beam (46) is monitored as it impinges on each device to determine the position of each device. The twist and sway of the tower is then determined using the positional information of the devices.

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Durham, CT, United States of America

Bruce E Truax