Hybrid electrostatic chuck
First Claim
1. An electrostatic chuck for electrostatically attracting and holding an object, comprising:
- a first layer having top and bottom surfaces, the first layer consisting essentially of an insulating material for attracting and supporting such object on its top surface;
a second layer having upper and lower surfaces, the second layer consisting essentially of a semiconducting material, the upper surface of the second layer being in contact with the bottom surface of the first layer;
an electrode formed on the lower surface of the second layer;
supporting means for supporting the first layer, the second layer and the electrode; and
electrical connection means for connecting an electric potential between the object and the electrode;
whereby an attractive electrostatic force will be generated between the object and the chuck.
1 Assignment
0 Petitions
Accused Products
Abstract
An electrostatic chuck comprises a hybrid dielectric between a wafer and an electrode. The hybrid dielectric is comprised of two layers; a thin insulating layer for attracting and holding the bottom of the wafer; and a mechanically and electrically robust semiconducting layer below. The resistivity of the semiconducting layer can cover a wider range of values for equivalent performance than has been achievable heretofore with Johnson-Rahbeck effect devices. The hybrid layer combines the high force/voltage ratio and quick charge/discharge features of a thin insulating dielectric chuck with the protection provided by a current limiting semiconducting layer. The hybrid layer chuck provides improved performance with simple, low cost structures.
97 Citations
18 Claims
-
1. An electrostatic chuck for electrostatically attracting and holding an object, comprising:
-
a first layer having top and bottom surfaces, the first layer consisting essentially of an insulating material for attracting and supporting such object on its top surface; a second layer having upper and lower surfaces, the second layer consisting essentially of a semiconducting material, the upper surface of the second layer being in contact with the bottom surface of the first layer; an electrode formed on the lower surface of the second layer; supporting means for supporting the first layer, the second layer and the electrode; and electrical connection means for connecting an electric potential between the object and the electrode; whereby an attractive electrostatic force will be generated between the object and the chuck. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. An electrostatic chuck for electrostatically attracting and holding an object, comprising
a first layer having top and bottom surfaces, the first layer consisting essentially of an insulating material for attracting and supporting the object on the top surface; -
a second layer having upper and lower surfaces, the second layer consisting essentially of a semiconductive material, the upper surface of the second layer being in contact with the bottom surface of the first layer; at least two planar electrodes formed on the lower surface of the second layer and separated by a gap therebetween, the electrodes forming a first and a second capacitor between the electrodes and the work object, wherein portions of the first layer and second layer form a series dielectric between the two capacitors; supporting means for supporting the electrodes, the second layer and the first layer; and electrical connection means for connecting an electric potential between the at least two electrodes; whereby an attractive electrostatic force will be generated between the object and the chuck. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17, 18)
-
Specification