Window protector for sputter etching of metal layers

Abstract

An inductively coupled plasma processing apparatus includes a chamber having a top opening. A window seals the top opening of the chamber, and the window has an inner surface that is exposed to an internal region of the chamber. A window protector for protecting the inner surface of the window is disposed within the chamber. The window protector is configured to prevent conductive etch byproducts from being deposited on the inner surface of the window in the form of a continuous loop. In one alternative embodiment, a plurality of window protectors is affixed to the inner surface of the window. In another embodiment, the window has a plurality of T-shaped or dovetail slots formed therein. In yet another embodiment, a plurality of rectangular slots is formed in the window and a window protector having corresponding slots is mounted against the inner surface of the window.

1 . An inductively coupled plasma processing apparatus, comprising: 
 a chamber having a top opening;    a window that seals the top opening of the chamber, the window having an inner surface that is exposed to an internal region of the chamber; and    a window protector for protecting the inner surface of the window disposed within the chamber, the window protector being configured to prevent conductive etch byproducts from being deposited on the inner surface of the window in the form of a continuous loop.    
   
   
       2 . The plasma processing apparatus of  claim 1 , wherein the window protector is disposed within the chamber such that the window protector is separated from the inner surface of the window by a distance in a range from 0.02 inch to 0.1 inch.  
   
   
       3 . The plasma processing apparatus of  claim 1 , wherein the window protector is comprised of a conducting material.  
   
   
       4 . The plasma processing apparatus of  claim 1 , wherein the window protector is comprised of an insulating material.  
   
   
       5 . The plasma processing apparatus of  claim 1 , wherein the window protector is comprised of a material having good adhesion properties.  
   
   
       6 . An inductively coupled plasma processing apparatus, comprising: 
 a chamber having a top opening;    a window that seals the top opening of the chamber, the window having an inner surface that is exposed to an internal region of the chamber; and    a window protector for protecting the inner surface of the window disposed within the chamber, the window protector being in the shape of a Faraday shield, and the window protector being separated from the inner surface of the window by a distance in a range from 0.02 inch to 0.1 inch.    
   
   
       7 . An inductively coupled plasma processing apparatus, comprising: 
 a chamber having a top opening;    a chuck for holding a wafer being processed disposed within the chamber;    a window that seals the top opening of the chamber, the window having an inner surface that is exposed to an internal region of the chamber; and    a plurality of window protectors affixed to the inner surface of the window, each of the plurality of window protectors having an upper surface that is affixed to the inner surface of the window and a lower surface that is exposed to the internal region of the chamber, the lower surface of each window protector having a cross-sectional width that is larger than a cross-sectional width of the upper surface of each window protector, and the plurality of window protectors being arranged on the inner surface of the window in a spaced apart relationship such that each region of the inner surface of the window that is in a line of sight of the wafer being processed is separated from an adjacent window protector by a region of the inner surface of the window that is not in the line of sight of the wafer being processed.    
   
   
       8 . The plasma processing apparatus of  claim 7 , wherein each of the plurality of window protectors is comprised of a nonmagnetic metal.  
   
   
       9 . The plasma processing apparatus of  claim 7 , wherein a cross section of each of the plurality of window protectors is T-shaped.  
   
   
       10 . An inductively coupled plasma processing apparatus, comprising: 
 a chamber having a top opening; and    a window that seals the top opening of the chamber, the window having an inner surface that is exposed to an internal region of the chamber, the inner surface of the window having a plurality of slots formed therein, the plurality of slots being arranged in the shape of a Faraday shield, and each of the plurality of slots having a slot opening and a slot width, with the slot width being larger than the slot opening.    
   
   
       11 . The plasma processing apparatus of  claim 10 , wherein each of the plurality of slots is a T-shaped slot or a dovetail slot cut directly into the window.  
   
   
       12 . The plasma processing apparatus of  claim 10 , wherein each of the plurality of slots is a rectangular slot cut directly into the window, and the plasma processing apparatus further comprises a window protector mounted against the inner surface of the window, the window protector having a plurality of slots formed therein, the plurality of slots formed in the window protector corresponding to the plurality of slots formed in the window, each of the plurality of slots formed in the window having a first slot width and each of the plurality of slots formed in the window protector having a second slot width, the first slot width being larger than the second slot width.  
   
   
       13 . The plasma processing apparatus of  claim 12 , wherein the window protector is comprised of a conducting material.  
   
   
       14 . The plasma processing apparatus of  claim 12 , wherein the window protector is comprised of an insulating material.  
   
   
       15 . The plasma processing apparatus of  claim 12 , wherein the window protector is comprised of a material having good adhesion properties.  
   
   
       16 . An inductively coupled plasma processing apparatus, comprising: 
 a chamber having a top opening;    a window that seals the top opening of the chamber, the window having an inner surface that is exposed to an internal region of the chamber; and    means for protecting the inner surface of the window from having conductive etch byproducts deposited thereon in the form of a continuous loop.