Methods and apparatus for holding and positioning semiconductor workpieces during electropolishing and/or electroplating of the workpieces

Abstract

A wafer chuck for holding a wafer during electropolishing and/or electroplating of the wafer includes a top section, a bottom section, and a spring member. In accordance with one aspect of the present invention, the top section and the bottom section are configured to receive the wafer for processing. The spring member is disposed on the bottom section and configured to apply an electric charge to the wafer. In accordance with another aspect of the present invention, the spring member contacts a portion of the outer perimeter of the wafer. In one alternative configuration of the present invention, the wafer chuck further includes a seal member to seal the spring member from the electrolyte solution used in the electropolishing and/or electroplating process.

1 - 50 . (canceled)  
     
     
         51 . A wafer chuck assembly for holding a wafer, the chuck assembly comprising: 
 a top section;    a bottom section that engages with the top section to hold the wafer between the top and bottom sections;    a shaft attached to the top section, wherein the shaft rotates to rotate the top and bottom sections when the top and bottom sections are engaged; and    a brush that contacts the shaft to transfer an electric charge to the shaft while the shaft rotates.    
     
     
         52 . The chuck assembly of  claim 51 , further comprising: 
 a spring member disposed between the bottom section and the wafer when the wafer is held between the top and bottom sections, wherein the spring member is electrically connected to the shaft to apply the electric charge to the wafer.    
     
     
         53 . The chuck assembly of  claim 52 , wherein the spring member is a coil spring, and wherein top portions of the coil spring contact the wafer when the wafer is held between the top and bottom sections.  
     
     
         54 . The chuck assembly of  claim 52 , further comprising: 
 a transmission line electrically connected to the shaft; and    a conducting member disposed on the bottom section, wherein the conducting member is electrically connected to the transmission line and the spring member to transmit the electrical charge to the spring member.    
     
     
         55 . The chuck assembly of  claim 54 , further comprising: 
 an electrode connected to the transmission line, wherein the electrode engages with the conducting member when the top and bottom sections are engaged, and wherein the electrode disengages from the conducting member when the top and bottom sections are disengaged.    
     
     
         56 . The chuck assembly of  claim 51 , further comprising: 
 a belt connected to the shaft; and    a motor connected to the belt to rotate the shaft.    
     
     
         57 . The chuck assembly of  claim 51 , further comprising: 
 a slip ring assembly having seals formed around the shaft, wherein a first pair of seals forms a first cavity through which a gas is introduced into a first channel formed in the shaft while the shaft rotates within the slip ring assembly.    
     
     
         58 . The chuck assembly of  claim 57 , further comprising: 
 a first nozzle assembly disposed in the bottom section to apply the gas; and    a second nozzle assembly disposed in the top section to apply the gas.    
     
     
         59 . The chuck assembly of  claim 57 , wherein a second pair of seals forms a second cavity through which a vacuum is applied to a second channel formed in the shaft while the shaft rotates within the slip ring assembly.  
     
     
         60 . The chuck assembly of  claim 59 , further comprising: 
 a vacuum chamber formed between the top and bottom sections; and    a vacuum line connected between the second channel formed in the shaft and the vacuum chamber to apply the vacuum to the vacuum chamber when the top and bottom sections are engaged.    
     
     
         61 . A wafer chuck assembly for holding a wafer, the chuck assembly comprising: 
 a top section;    a bottom section that engages with the top section to hold the wafer;    a shaft attached to the top section;    a motor connected to the shaft to rotate the shaft;    a brush that contacts the shaft to transfer an electric charge to the shaft while the shaft rotates; and    a slip ring assembly having seals formed around the shaft, wherein a first pair of seals forms a first cavity through which a gas is introduced into a first channel formed in the shaft while the shaft rotates within the slip ring assembly, and wherein a second pair of seals forms a second cavity through which a vacuum is applied to a second channel formed in the shaft while the shaft rotates within the slip ring assembly.    
     
     
         62 . The chuck assembly of  claim 61 , further comprising: 
 a spring member disposed between the bottom section and the wafer when the wafer is held between the top and bottom sections, wherein the spring member is electrically connected to the shaft to apply the electric charge to the wafer.    
     
     
         63 . The chuck assembly of  claim 62 , wherein the spring member is a coil spring, and wherein top portions of the coil spring contact the wafer when the wafer is held between the top and bottom sections.  
     
     
         64 . The chuck assembly of  claim 62 , further comprising: 
 a transmission line electrically connected to the shaft; and    a conducting member disposed on the bottom section, wherein the conducting member is electrically connected to the transmission line and the spring member to transmit the electrical charge to the spring member.    
     
     
         65 . The chuck assembly of  claim 64 , further comprising: 
 an electrode connected to the transmission line, wherein the electrode engages with the conducting member when the top and bottom sections are engaged, and wherein the electrode disengages from the conducting member when the top and bottom sections are disengaged.    
     
     
         66 . The chuck assembly of  claim 61 , further comprising: 
 a belt connected to the shaft and the motor to rotate the shaft.    
     
     
         67 . The chuck assembly of  claim 61 , further comprising: 
 a first nozzle assembly disposed in the bottom section to apply the gas; and    a second nozzle assembly disposed in the top section to apply the gas.    
     
     
         68 . The chuck assembly of  claim 61 , further comprising: 
 a vacuum chamber formed between the top and bottom sections; and    a vacuum line connected between the second channel formed in the shaft and the vacuum chamber to apply the vacuum to the vacuum chamber when the top and bottom sections are engaged.    
     
     
         69 . A method of holding a wafer with a wafer chuck, the method comprising: 
 engaging a top section with a bottom section of the wafer chuck to hold the wafer between the top and bottom sections;    rotating a shaft attached to the top section to rotate the top and bottom sections when the top and bottom sections are engaged; and    applying an electric charge using a brush that contacts the shaft to transfer the electric charge to the shaft while the shaft rotates.    
     
     
         70 . The method of  claim 69 , further comprising: 
 applying the electric charge to the wafer through a spring member disposed between the bottom section and the wafer when the wafer is held between the top and bottom sections, wherein the spring member is electrically connected to the shaft.    
     
     
         71 . The method of  claim 69 , further comprising: 
 introducing a gas into a first channel formed in the shaft through a slip ring assembly having seals formed around the shaft while the shaft rotates within the slip ring assembly.    
     
     
         72 . The method of  claim 69 , further comprising: 
 applying a vacuum to a second channel formed in the shaft through the slip ring assembly while the shaft rotates within the slip ring assembly.