Browse Prior Art Database

X-Y Stage for X-ray Lithography

IP.com Disclosure Number: IPCOM000122390D
Original Publication Date: 1991-Dec-01
Included in the Prior Art Database: 2005-Apr-04
Document File: 3 page(s) / 74K

Publishing Venue

IBM

Related People

Bozso, FM: AUTHOR [+3]

Abstract

Disclosed is an x-y stage where the course positioning mechanism (usually stepper motor driven) and the fine positioning (usually piezoelectric driven) are combined in a piezoelectric drive. No magnetic material is used, so the device can be used for electron beam lithography, and no vacuum feedthrough mechanisms are needed for mechanical drives into a vacuum. The cost of the mechanism should be much less than that of the conventional two-stage drive mechanism.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 59% of the total text.

X-Y Stage for X-ray Lithography

      Disclosed is an x-y stage where the course positioning
mechanism (usually stepper motor driven) and the fine positioning
(usually piezoelectric driven) are combined in a piezoelectric drive.
No magnetic material is used, so the device can be used for electron
beam lithography, and no vacuum feedthrough mechanisms are needed for
mechanical drives into a vacuum.  The cost of the mechanism should be
much less than that of the conventional two-stage drive mechanism.

      The device is shown (Fig. 1) for just one axis of motion with
no rotational capability.  When a voltage is applied across the
piezoelectric elements 1 from electrode 2 to electrode 3, the
elements will distort, as shown in Fig. 2.  A voltage waveform shown
in Fig. 3 will cause the sapphire plate 4 to move in the x direction.
The sapphire plate 5, carrying the wafer 6 to be exposed, will move
in the x direction in a quasi-continuous way because the two sapphire
plates 4 and 5 will slide against each other in the "snap back" part
of the motion of plate 4, and will stick together by friction in the
slower moving part of the motion.  When the part is approximately at
the right position, the plate 4 can be moved slowly so that the plate
5 and the wafer 6 will not move relative to plate 4, so the part
can be placed exactly.

      An x stage with rotary motion can be built where the electrodes
are split so that opposite voltage gradients can be applied to each
s...