Bipolar Electrostatic Chuck

Abstract

A bipolar electrostatic chuck which has excellent dielectric breakdown strength and provides excellent attracting performance. The bipolar electrostatic chuck eliminates difficulty in dismounting a sample from a sample attracting plane as much as possible after application of a voltage to electrodes is finished. The bipolar electrostatic chuck is provided with a first electrode and a second electrode in an insulator and permits a surface of the insulator to be the sample attracting plane. The insulator has the first electrode, an interelectrode insulating layer and the second electrode in this order from the sample attracting plane in the depth direction. The second electrode has a region not overlapping with the first electrode in a normal line direction of the sample attracting plane.

1 . A bipolar electrostatic chuck which has a first electrode and a second electrode in an interior of an insulating material, generates at least an attracting performance by a gradient force, and attracts a sample by allowing a surface of the insulating material to function as a sample attracting plane, characterized in that: 
 the insulating material is formed by laminating an upper insulating layer, the first electrode, an interelectrode insulating layer, the second electrode, and a lower insulating layer in the order of distance from the sample attracting plane in a depth direction of the insulating material; and    when the sample attracting plane is viewed in a depth direction, the second electrode has an area that is not overlapped with the first electrode, a plurality of first electrodes and a plurality of second electrodes being alternately arranged in a direction in which the area that is not overlapped is crossed a plurality of times.    
   
   
       2 - 3 . (canceled)  
   
   
       4 . The bipolar electrostatic chuck according to  claim 1 , wherein: 
 the first electrode is formed in a band-like comb teeth configuration;    the second electrode is formed in a band-like comb teeth configuration;    when the sample attracting plane is viewed in the depth direction, the band-like comb teeth of the first and second electrodes are alternately arranged; and    the second electrode is not overlapped with the first electrode.    
   
   
       5 . (canceled)  
   
   
       6 . The bipolar electrostatic chuck according to  claim 1 , wherein: 
 the first electrode is formed in a band-like comb teeth configuration;    the second electrode is formed in a plane having a given planar area; and    a part of the second electrode is overlapped with the first electrode when the sample attracting plane is viewed in the depth direction.    
   
   
       7 . The bipolar electrostatic chuck according to  claim 1 , wherein: 
 the first electrode is formed in a curb configuration;    the second electrode is formed in a plane having a given planar area; and    a part of the second electrode is overlapped with the first electrode when of the sample attracting plane is viewed in the depth direction.    
   
   
       8 . The bipolar electrostatic chuck according to  claim 1 , wherein: 
 the first electrode is formed in a mesh configuration having a plurality of openings each within a given area;    the second electrode is formed in a plane having a given planar area; and    a part of the second electrode is overlapped with the first electrode when the sample attracting plane is viewed in the depth direction.    
   
   
       9 . (canceled)  
   
   
       10 . The bipolar electrostatic chuck according to  claim 1 , wherein: 
 the first electrode centers on a circular portion having a given circular area, has a plurality of first annular portion that are concentrically disposed at a given interval, and has a first connection portion that connects the circular portion and the first annular portions to each other;    the second electrode has a plurality of second annular portions having a width smaller than the interval which are concentrically disposed, is formed to have a second connection portion that connects the second annular portions to each other, the first annular portions and the second annular portions being alternately disposed when of the sample attracting plane is viewed in the depth direction.    
   
   
       11 . The bipolar electrostatic chuck according to  claim 1 , wherein: 
 the first electrode centers on a circular portion having a given circular area, has a plurality of first annular portions that are concentrically disposed at a given interval, and has a first connection portion that connects the circular portion and the first annular portions to each other; and    the second electrode has a plurality of second annular portions having a width same as the interval which are concentrically disposed, is formed to have a second connection portion that connects the second annular portions to each other, the first annular portions and the second annular portions being alternately disposed when of the sample attracting plane is viewed in the depth direction.    
   
   
       12 . (canceled)  
   
   
       13 . The bipolar electrostatic chuck according to  claim 1 , wherein a distance between the first electrode and the second electrode is equal to or more than 1 μm and equal to or less than 1000 μm.  
   
   
       14 . The bipolar electrostatic chuck according to  claim 1 , wherein: 
 the first electrode is formed in a band-like comb teeth configuration; and    in the case where a band-like electrode width z of the first electrode and an interelectrode gap z are made equal to each other, z is in a range of 0.15 to 0.5 mm.    
   
   
       15 . The bipolar electrostatic chuck according to  claim 1 , wherein the interelectrode insulating layer is formed of a resin layer made of one or more resins selected from the group consisting of polyimide, polyamide-imide, polyester, polyethylene terephthalate, epoxy, and acryl.  
   
   
       16 . The bipolar electrostatic chuck according to  claim 1 , wherein the resin layer is formed of one or more resin films.  
   
   
       17 . The bipolar electrostatic chuck according to  claim 1 , wherein the interelectrode insulating layer is formed of a ceramic layer made of one or more elements selected from the group consisting of aluminum oxide, aluminum nitride, silicon carbide, silicon nitride, zirconia, and titania.  
   
   
       18 . The bipolar electrostatic chuck according to  claim 1 , wherein the interelectrode insulating layer is formed of one or two elements selected from the group consisting of silicon and silicon dioxide.  
   
   
       19 . The bipolar electrostatic chuck according to  claim 1 , wherein: 
 an electrically conductive layer is further formed on the surface of the insulating material; and    the surface of the electrically conductive layer serves as the sample attracting plane.    
   
   
       20 . The bipolar electrostatic chuck according to  claim 1 , wherein a sectional configuration of a part or all of the first electrode taken along the depth direction of the sample attracting plane comprises a configuration selected from the group consisting of a rectangle, a square, a circle, and a triangle.  
   
   
       21 . The bipolar electrostatic chuck according to  claim 1 , wherein a sectional configuration of a part or all of the second electrode taken along the depth direction of the sample attracting plane comprises a configuration selected from the group consisting of a rectangle, a square, a circle, and a triangle.