Plasma ashing/etching using solid sapphire disk

Abstract

Plasma ashing and/or etching using a solid sapphire disk is disclosed. A plasma etcher/asher of one embodiment of the invention includes at least a chamber body, upper and lower baffles, and a solid sapphire disk. The chamber body defines an interior chamber in which a semiconductor wafer is positionable for etching or ashing. The baffles are positioned over the semiconductor wafer, and distribute gas onto the semiconductor wafer. The solid sapphire disk has no holes, and is positioned over one of the baffles to affect distribution of the gas onto the semiconductor wafer. The solid sapphire disk of the invention provides for more uniform distribution of the gas onto the semiconductor wafer. As a result, etching or ashing of the semiconductor wafers occurs more uniformly, providing for more uniformly thick wafers.

We claim:  
     
         1 . A plasma etcher/asher comprising: 
 a chamber body defining an interior chamber in which a semiconductor wafer is positionable;    an upper baffle and a lower baffle positioned over the semiconductor wafer, the upper and the lower baffles distributing gas onto the semiconductor wafer; and,    a solid sapphire disk positioned over one of the upper and the lower baffles to affect distribution of the gas onto the semiconductor wafer.    
     
     
         2 . The plasma etcher/asher of  claim 1 , further comprising a chamber dome covering the chamber body, a process gas inlet port disposed within the chamber dome.  
     
     
         3 . The plasma etcher/asher of  claim 1 , further comprising a pump port disposed within a bottom of the chamber body.  
     
     
         4 . The plasma etcher/asher of  claim 1 , further comprising a chuck on which the semiconductor wafer rests.  
     
     
         5 . The plasma etcher/asher of  claim 4 , further comprising a cooling jacket for the chuck.  
     
     
         6 . The plasma etcher/asher of  claim 1 , wherein the solid sapphire disk is positioned substantially on one of the upper and the lower baffles.  
     
     
         7 . The plasma etcher/asher of  claim 1 , wherein the solid sapphire disk is positioned substantially on the upper baffle.  
     
     
         8 . The plasma etcher/asher of  claim 1 , wherein the solid sapphire disk affects the distribution of the gas onto the semiconductor wafer such that the gas is substantially uniformly distributed onto the semiconductor wafer, and etching/ashing of the semiconductor wafer occurs substantially uniformly.  
     
     
         9 . The plasma etcher/asher of  claim 1 , wherein the plasma etcher/asher is a plasma etcher.  
     
     
         10 . The plasma etcher/asher of  claim 1 , wherein the plasma etcher/asher is a plasma asher.  
     
     
         11 . A plasma etcher/asher comprising: 
 a chamber body defining an interior chamber;    a chuck within the chamber body on which a semiconductor wafer can rest;    a chamber dome covering the chamber body and defining a process gas inlet port;    an upper baffle and a lower baffle positioned over the semiconductor wafer, the upper and the lower baffles distributing gas onto the semiconductor wafer; and,    a solid sapphire disk positioned over one of the upper and the lower baffles to affect distribution of the gas onto the semiconductor wafer.    
     
     
         12 . The plasma etcher/asher of  claim 11 , further comprising a pump port disposed within a bottom of the chamber body.  
     
     
         13 . The plasma etcher/asher of  claim 12 , further comprising a cooling jacket for the chuck.  
     
     
         14 . The plasma etcher/asher of  claim 11 , wherein the solid sapphire disk is positioned substantially on the upper baffle.  
     
     
         15 . The plasma etcher/asher of  claim 11 , wherein the solid sapphire disk affects the distribution of the gas onto the semiconductor wafer such that the gas is substantially uniformly distributed onto the semiconductor wafer, and etching/ashing of the semiconductor wafer occurs substantially uniformly.  
     
     
         16 . The plasma etcher/asher of  claim 11 , wherein the plasma etcher/asher is only one of a plasma etcher and a plasma asher.  
     
     
         17 . A plasma etcher/asher comprising: 
 a chamber body defining an interior chamber in which a semiconductor wafer is positioned;    an upper baffle and a lower baffle positioned over the semiconductor wafer, the upper and the lower baffles distributing gas onto the semiconductor wafer; and,    a metallic disk without holes positioned over one of the upper and the lower baffles to affect distribution of the gas onto the semiconductor wafer.    
     
     
         18 . The plasma etcher/asher of  claim 17 , wherein the metallic disk without holes is a solid sapphire disk.  
     
     
         19 . The plasma etcher/asher of  claim 17 , wherein the metallic disk affects the distribution of the gas onto the semiconductor wafer such that the gas is substantially uniformly distributed onto the semiconductor wafer, and etching/ashing of the semiconductor wafer occurs substantially uniformly.  
     
     
         20 . The plasma etcher/asher of  claim 17 , wherein the plasma etcher/asher is only one of a plasma etcher and a plasma asher.