Alignment stage

Abstract

In an alignment stage, a top table 4 a , which holds a work piece on which a moving load acts, is disposed above a base 1 , and a supporting unit 13 each having three degrees of freedom of X, Y, and θ and driving units 14 A, 14 B, 14 C, and 14 D, each having a one-axis direction ball screw linear motion mechanism 9 in addition to the same configuration as that of the supporting unit 13 , are interposed between the base 1 and the top table 4 a to be disposed at locations corresponding to the center and four corner portions of the top table 4 a , which are disposed in a zigzag fashion in a load movement direction L. The ball screw linear motion mechanisms 9 of the driving units 14 A and 14 B of diagonal positions on one side and the ball screw linear motion mechanisms 9 of the driving units 14 C and 14 D of diagonal positions on the other side are disposed to be at right angles to each other. A moving load which acts on the top table 4 a through a work piece while moving in the load movement direction L is continuously received by the respective driving units 14 A and 14 C, the supporting unit 13 , and the respective driving units 14 B and 14 D, so that deformation of the top table 4 a is suppressed.

1 . An alignment stage comprising:
 a base;   a top table which is disposed at a position above the base and holds a work piece on which a moving load acts;   a required number of supporting units which are each composed of guides slidable in two directions orthogonal to each other and a turning bearing provided over the guide and each have three degrees of freedom of X, Y, and θ; and   at least three driving units which are composed by providing the supporting unit with a one-axis direction linear motion mechanism,   wherein the supporting units and the driving units are provided disposed in a zigzag fashion along a movement direction of the moving load between the base and the top table, and   driving directions by the linear motion mechanisms of two driving units among the respective driving units and a driving directions by the linear motion mechanisms of the remaining driving unit are at right angles to each other in the X-Y plane.   
     
     
         2 . The alignment stage according to  claim 1 , wherein the disposition in a zigzag fashion is made by locations corresponding to the four corner portions and the center of the top table. 
     
     
         3 . The alignment stage according to  claim 1 , wherein the disposition in a zigzag fashion is made by locations corresponding to the four corner portions and the center of the top table, the respective driving units are provided at the locations corresponding to the four corner portions of the top table, and the supporting unit is provided at the location corresponding to the center of the top table. 
     
     
         4 . An alignment stage comprising:
 a base;   a top table which is disposed at a position above the base and holds a work piece on which a moving load acts; and   driving units which are each composed of guides slidable in two directions orthogonal to each other and a turning bearing provided over the guide, each have three degrees of freedom of X, Y, and θ, and each include a one-axis direction linear motion mechanism,   wherein the driving units are provided disposed in a zigzag fashion along a movement direction of the moving load between the base and the top table, and   driving directions by the linear motion mechanisms of two driving units among the respective driving units and driving directions by the linear motion mechanisms of the remaining two driving units are at right angles to each other in the X-Y plane.   
     
     
         5 . The alignment stage according to  claim 1 , wherein the disposition in a zigzag fashion is made by locations corresponding to positions on lines each connecting an intermediate position of each side of the top table to the center of the top table. 
     
     
         6 . The alignment stage according to  claim 1 , wherein the linear motion mechanism is constituted by a ball screw linear motion mechanism which includes a motor, a screw shaft connected to an output shaft of the motor, and a nut member thread-engaged with the screw shaft, and the motor is disposed to protrude to the outside of the base. 
     
     
         7 . The alignment stage according to  claim 5 , wherein the linear motion mechanism is constituted by a ball screw linear motion mechanism which includes a motor, a screw shaft connected to an output shaft of the motor, and a nut member thread-engaged with the screw shaft, and the motor is disposed to protrude to the outside of the base. 
     
     
         8 . The alignment stage according to  claim 1 , wherein a linear scale for detecting a driving amount by the one-axis direction linear motion mechanism of each of the driving units is provided on the base adjacent to each of the driving units. 
     
     
         9 . The alignment stage according to  claim 5 , wherein a linear scale for detecting a driving amount by the one-axis direction linear motion mechanism of each of the driving units is provided on the base adjacent to each of the driving units. 
     
     
         10 . The alignment stage according to  claim 6 , wherein a linear scale for detecting a driving amount by the one-axis direction linear motion mechanism of each of the driving units is provided on the base adjacent to each of the driving units. 
     
     
         11 . The alignment stage according to  claim 7 , wherein a linear scale for detecting a driving amount by the one-axis direction linear motion mechanism of each of the driving units is provided on the base adjacent to each of the driving units.