Plasma treating apparatus and plasma treating method

Abstract

In a plasma treating apparatus for carrying out a plasma treatment over a silicon wafer 6 having a protective tape 6 a stuck to a circuit formation face, the silicon wafer 6 is mounted on a mounting surface 3 d which is provided on an upper surface of a lower electrode 3 formed of a conductive metal with the protective tape 6 a turned toward the mounting surface 3 d . When a DC voltage is to be applied to the lower electrode 3 by a DC power portion 18 for electrostatic adsorption to adsorb and hold the silicon wafer 6 onto the lower electrode 3 in the plasma treatment, the protective tape 6 a is utilized as a dielectric for the electrostatic adsorption. Consequently, the dielectric can be thinned as much as possible and the silicon wafer 6 can be held by a sufficient electrostatic holding force.

1 . A plasma treating apparatus for carrying out a plasma treatment over a semiconductor substrate having an insulating layer on a surface, comprising: 
 a substrate mounting portion provided with a mounting surface having a conductor exposed to at least a part thereof and serving to mount the semiconductor substrate with an insulating layer side turned toward the mounting surface;    electrostatic adsorbing means for holding the semiconductor substrate on the mounting surface by electrostatic adsorption; and    plasma generating means for generating a plasma in order to treat the semiconductor substrate mounted on the mounting surface,    wherein said insulating layer of the semiconductor substrate is utilized as a dielectric for the electrostatic adsorption.    
   
   
       2 . The plasma treating apparatus according to  claim 1 , wherein the insulating layer is a resin tape stuck to the surface of the semiconductor substrate.  
   
   
       3 . The plasma treating apparatus according to  claim 2 , wherein a material of the resin tape is one of polyolefin, polyimide and polyethylene terephthalate.  
   
   
       4 . The plasma treating apparatus according to  claim 1 , wherein the semiconductor substrate is a silicon wafer having a circuit formation face and the insulating layer is a protective tape for protecting the circuit formation face.  
   
   
       5 . The plasma treating apparatus according to  claim 4 , wherein a material of the protective tape is one of polyolefin, polyimide and polyethylene terephthalate.  
   
   
       6 . The plasma treating apparatus according to  claim 1 , wherein the semiconductor substrate is a silicon wafer having a circuit formation face and the insulating layer is an insulating resin layer formed to seal the circuit formation face.  
   
   
       7 . The plasma treating apparatus according to  claim 1 , wherein the semiconductor substrate is a silicon wafer having a circuit formation face and the insulating layer is an insulating resin layer provided to form a wiring layer on the circuit formation face.  
   
   
       8 . The plasma treating apparatus according to  claim 1 , further comprising vacuum holding means for vacuum adsorbing the semiconductor substrate by vacuum suction through an adsorption hole opened to the mounting surface and holding the semiconductor substrate on the mounting surface, the semiconductor substrate being held on the mounting surface by the vacuum holding means before a plasma is generated by at least the plasma generating means.  
   
   
       9 . The plasma treating apparatus according to  claim 1 , further comprising cooling means for cooling the substrate mounting portion.  
   
   
       10 . The plasma treating apparatus according to  claim 8 , further comprising heat transfer gas feeding means for feeding a gas for heat transfer to the adsorption hole.  
   
   
       11 . The plasma treating apparatus according to  claim 1 , wherein the mounting portion includes a larger mounting surface than the semiconductor substrate, a portion of the mounting surface to which a conductor is exposed is provided in a central part of the mounting surface, and an outer edge portion protruded from the semiconductor substrate on an outside thereof is formed of an insulator.