05874820 is referenced by 410 patents and cites 65 patents.

A guided stage mechanism suitable for supporting a reticle in a photolithography machine includes a stage movable in the X-Y directions on a base. Laterally surrounding the stage is a rectangular window frame guide which is driven in the X-axis direction on two fixed guides by means of motor coils on the window frame guide co-operating with magnetic tracks fixed on the base. The stage is driven inside the window frame guide in the Y-axis direction by motor coils located on the stage co-operating with magnetic tracks located on the window frame guide. Forces from the drive motors of both the window frame guide and the stage are transmitted through the center of gravity of the stage, thereby eliminating unwanted moments of inertia. Additionally, reaction forces caused by the drive motors are isolated from the projection lens and the alignment portions of the photolithography machine. This isolation is accomplished by providing a mechanical support for the stage independent of the support for its window frame guide. The window frame guide is a hinged structure capable of a slight yawing (rotational) motion due to hinged flexures which connect the window frame guide members.

Title
Window frame-guided stage mechanism
Application Number
8/416558
Publication Number
5874820
Application Date
April 4, 1995
Publication Date
February 23, 1999
Inventor
Martin E Lee
Saratoga
CA, US
Agent
Skjerven Morrill MacPherson Franklin & Friel
Agent
Norman R Klivans
Assignee
Nikon Corporation
JP
IPC
H01L 21/027
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