Abstract:
Integrated circuit mask patterns are laser machined by mounting substrates on a support that is periodically stepped in a y direction after each scan by a laser writing beam in an x direction. X-direction scanning is accomplished by mounting a mirror on a carriage that reciprocates by rebounding between two displaced coil springs. A coding laser beam is reflected from the carriage through a stationary code plate, comprising alternate transparent and opaque stripes, to monitor the position of the carriage and to control the modulation of the writing beam.
Abstract:
A wafer alignment device comprises a support platform supported by three flexible rods extending downwardly to a linking ring. Three flexible rods extend upwardly from the linking ring to a stationary table. The support platform can be moved in x, y and theta directions, to align the wafer with great accuracy and without accompanying z-direction motion, for photolithographic printing purposes.
Abstract:
The polygonal mirror of a light beam scanner is aligned on a shaft by three mounting fixtures, each comprising a stiff spring bearing against one side of the mirror and a relatively soft spring bearing against the opposite side. The soft spring is compressed against the mirror by a bolt. The rotational plane of the mirror is adjusted by threading the bolts toward or away from the mirror.
Abstract:
A table is reciprocated along a straight line by a force that does not precisely control movement direction. Accurate motion constraint is provided by two separated air bearings arranged along a common axis. A third air bearing, displaced from the common axis, supports the table on a sleeve that is free to rotate on its axis.
Abstract:
A lead screw apparatus is disclosed that permits fine adjustments to be made in the screw pitch. A lead screw shaft having N threads, an initial length L, and a spring constant K1 is coaxially connecting to a spring having a spring constant K2 substantially smaller than K1. By deforming the spring by a distance delta 2, a force equal to delta 2K2 is generated. This force is transmitted to the lead screw, producing a change in length of the screw of delta 1 where delta 1 is equal to delta 2K2/K1. Since K2 is substantially smaller than K1, delta 1 will be substantially smaller than delta 2 by the same order of magnitude. Thus a large change delta 2 in the length of the spring will change the pitch of the lead screw from N/L to N/L + OR - + OR - delta 1.