High density plasma CVD chamber

Abstract

The present invention is directed to the design of a plasma CVD chamber which provides more uniform conditions for forming thin CVD films on a substrate. In one embodiment, an apparatus for processing semiconductor substrates comprises a chamber defining a plasma processing region therein. The chamber includes a bottom, a side wall, and a dome disposed on top of the side wall. The dome has a dome top and having a side portion defining a chamber diameter. A top RF coil is disposed above the dome top. A side RF coil is disposed adjacent the side portion of the dome. The side RF coil is spaced from the top RF coil by a coil separation. A ratio of the coil separation to the chamber diameter is typically at least about 0.15, more desirably about 0.2-0.25.

1 . An apparatus for processing semiconductor substrates, the apparatus comprising: 
 a chamber defining a plasma processing region therein, the chamber including a bottom, a side wall, and a dome disposed on top of the side wall; and    a vacuum system including a pump and a gate valve disposed in a lower chamber portion of the chamber near the bottom, the gate valve being a throttle gate valve with pressure throttling capability.    
   
   
       2 . The apparatus of  claim 1  further comprising a screen disposed above the gate valve.  
   
   
       3 . An apparatus for processing semiconductor substrates, the apparatus comprising: 
 a chamber defining a plasma processing region therein, the chamber including a bottom, a side wall, and a dome disposed on top of the side wall;    a substrate support disposed in the chamber to support a substrate;    a vacuum system including a pump disposed below the substrate support and a gate valve disposed in a lower chamber portion of the chamber near the bottom; and    a screen disposed above the gate valve.    
   
   
       4 . The apparatus of  claim 3  wherein the screen comprises aluminum.  
   
   
       5 . The apparatus of  claim 3  wherein the vacuum system further comprises a throttle valve disposed above the gate valve and above the screen.  
   
   
       6 . The apparatus of  claim 3  wherein the vacuum system further comprises a throttle valve disposed above the gate valve and below the screen.  
   
   
       7 . The apparatus of  claim 3  wherein the gate valve is a throttle gate valve with pressure throttling capability.  
   
   
       8 . The apparatus of  claim 3  wherein the screen is grounded.  
   
   
       9 . The apparatus of  claim 3  wherein a potential is applied to the screen.