Diamond conditioning of soft chemical mechanical planarization/polishing (CMP) polishing pads

Abstract

Conditioning of chemical mechanical planarization (CMP) using conventional diamond-embedded abrasive strips are well suited to condition conventional “hard” polishing but not soft polishing pads because the diamonds not only remove waste material, but they also damage the polishing surface of the pad. Embodiments of the present invention condition soft polishing pads using diamond strips without damaging the soft polishing pad.

1 . A method of conditioning a chemical mechanical planarization (CMP) polishing pad, comprising: 
 conditioning a soft polishing pad using diamond conditioner by: 
 rotating the soft polishing pad on a platen;  
 rinsing the soft polishing pad; and  
 passing a diamond conditioner over the soft polishing pad.  
   
   
   
       2 . The method of  claim 1 , further comprising rinsing the soft polishing pad with deionized water.  
   
   
       3 . The method of  claim 2 , further comprising: 
 applying zero pounds per square inch (psi) to the soft polishing pad from the platen.    
   
   
       4 . The method of  claim 1 , wherein passing the conditioning arm having the diamond conditioner thereon over the soft polishing pad comprises passing the diamond conditioner over the soft polishing pad during wafer polishing.  
   
   
       5 . The method of  claim 1 , wherein passing the conditioning arm having the diamond conditioner thereon over the soft polishing pad comprises passing the diamond conditioner over the soft polishing pad between wafer polishings.  
   
   
       6 . The method of  claim 1 , further comprising rotating a wafer against the soft polishing pad.  
   
   
       7 . The method of  claim 6 , further comprising applying slurry to the surface of the soft polishing pad.  
   
   
       8 . A chemical mechanical planarization (CMP) system, comprising: 
 a head mounted in a housing;    a wafer mounted to the head;    a platen mounted in the housing;    a soft polishing pad mounted to the platen;    a pad conditioning arm mounted in the housing; and    a diamond conditioner mounted to the pad conditioning arm.    
   
   
       9 . The system of  claim 8 , further comprising a slurry tank mounted in the housing.  
   
   
       10 . The system of  claim 9 , further comprising a water tank mounted in the housing.  
   
   
       11 . The system of  claim 8 , further comprising electromechanical equipment mounted in the housing.  
   
   
       12 . The system of  claim 8 , wherein the soft polishing pad comprises napped poromerics-porous urethane layers on a substantially compressible substrate.  
   
   
       13 . (canceled)  
   
   
       14 . The system of  claim 8 , wherein the diamond conditioner comprises a diamond strip.  
   
   
       15 . The system of  claim 14 , wherein the diamond strip comprises synthetic diamonds embedded in a base.  
   
   
       16 . The system of  claim 8 , wherein the pad conditioning arm is to apply approximately 0.25 pounds per square inch (psi) to the soft polishing pad through the diamond conditioner.  
   
   
       17 . The system of  claim 8 , wherein the platen is to rotate during conditioning of the soft polishing pad.  
   
   
       18 . The system of  claim 17 , wherein the platen is to rotate at a rotational speed of approximately one hundred revolutions per minute (RPM).  
   
   
       19 . The system of  claim 18 , wherein the diamond conditioner is to make a single sweep across the soft polishing pad during conditioning of the soft polishing pad.  
   
   
       20 . A chemical mechanical planarization (CMP) apparatus, comprising: 
 a soft polishing pad adhered to a platen in a housing, the soft polishing pad comprising a porous thermoplastic resin matrix reinforced with a felted mat of polyester fibers; and    a pad conditioning arm mounted in the housing, the pad conditioning arm having a diamond conditioner attached thereto, the diamond conditioner to condition the soft polishing pad.    
   
   
       21 . The CMP apparatus of  claim 20 , wherein the conditioning arm is to apply approximately 0.25 pounds per square inch (psi) to the soft polishing pad through the diamond conditioner.  
   
   
       22 . The CMP apparatus of  claim 20 , wherein the platen is to rotate during conditioning of the soft polishing pad.  
   
   
       23 . The CMP apparatus of  claim 22 , wherein the platen is to rotate at a rotational speed of approximately one hundred revolutions per minute (RPM).  
   
   
       24 . The CMP apparatus of  claim 20 , wherein the diamond conditioner is to make a single sweep across the soft polishing pad during conditioning of the soft polishing pad.  
   
   
       25 . A chemical mechanical planarization (CMP) apparatus, comprising: 
 a housing having a platen;    a soft polishing pad adhered to the platen, the soft polishing pad comprising a felt sheet of fibers impregnated with micro porous elastomer; and    a pad conditioning arm mounted in the housing, the pad conditioning arm having a diamond conditioner attached thereto, the diamond conditioner to condition the soft polishing pad.    
   
   
       26 . The CMP apparatus of  claim 25 , wherein the platen is to rotate during conditioning of the soft polishing pad.  
   
   
       27 . The CMP apparatus of  claim 26 , wherein the soft polishing pad is to receive de-ionized (DI) water during conditioning of the soft polishing pad.  
   
   
       28 . The CMP apparatus of  claim 25 , wherein the diamond conditioner comprises diamond particles embedded in nickel coated on a surface of a rigid substrate.  
   
   
       29 . The CMP apparatus of  28 , wherein the diamond conditioner comprises synthetic and/or natural diamond particles.