Method and device for feeding a chemical-mechanical polishing machine with a polishing product

Abstract

In a chemical-mechanical polishing machine, polishing product comprising abrasive particles suspended in a reactive liquid is fed to the machine for use in a polishing operation that is divided into at least a first step and a second step. During the second step, the polishing machine is fed via a filter with a product containing fewer large particles than the product feeding the polishing machine during the first step. The feed device may be formed of two parallel lines which are provided with valves. At least one of those lines is provided with the filter.

1 . A method of feeding a chemical-mechanical polishing machine with a polishing product comprising abrasive particles suspended in a reactive liquid, for the purpose of carrying out a polishing operation on a surface of a part to be treated, during which the polishing product is interposed between this surface and a polishing plate covered with a polishing cloth, comprising: 
 dividing the polishing operation into at least a first step and a second step; and    feeding the polishing machine during the second step with a product containing particles having a different particle size distribution from that of the particles contained in the product feeding the polishing machine during the first step.    
   
   
       2 . The method according to  claim 1 , further comprising obtaining the product feeding the polishing machine during the second step by: 
 filtering the product feeding the polishing machine during the first step, and    retaining the particles whose size is greater than a predetermined value.    
   
   
       3 . The method according to either of  claim 1 , comprising feeding the polishing machine with a polishing product either directly during the first step or, after filtering the polishing product through a particle filter that retains relatively larger particles during the second step.  
   
   
       4 . The method according to  claim 1 , wherein said first step of the polishing operation removes a greater thicknesses of material from the surface of the part to be treated than said second step of the polishing operation.  
   
   
       5 . A device for feeding a chemical-mechanical polishing machine with a polishing product comprising abrasive particles suspended in a reactive liquid, comprising: 
 a first line connected to a source of polishing product;    a second line connected to the polishing machine;    at least two secondary parallel lines coupled between the first and second lines;    a particle filter in at least one of the first and second lines and operable to retain relatively larger particles of the polishing product;    means for selectively closing off one of said secondary lines so as to feed the polishing machine either directly with the polishing product coming from the source or with the polishing product coming from the source and filtered by the particle filter which retains particles having a size greater than a predetermined value.    
   
   
       6 . A polishing product feeding system for a chemical-mechanical polishing machine, comprising: 
 a first line for delivering polishing product containing particles having a first particle size distribution to the chemical-mechanical polishing machine; and    a second line for delivering polishing product containing particles having a second particle size distribution to the chemical-mechanical polishing machine.    
   
   
       7 . The system of  claim 6  wherein the polishing product comprising abrasive particles of various sizes suspended in a reactive liquid, and wherein the second particle size distribution differs from the first particle size distribution in that the second particle size distribution does not include relatively larger sized particles which are contained in the first particle size distribution.  
   
   
       8 . The system of  claim 6  further including a polishing product delivery line which is coupled to receive product sourced from the first and second lines and deliver that product to the chemical-mechanical polishing machine.  
   
   
       9 . The system of  claim 6  further including: 
 a polishing product source container for delivering polishing product containing particles having the first particle size distribution to each of the first and second lines; and    a particle filter associated with the second line and operable to create polishing product containing particles having the second particle size distribution from the polishing product containing particles having the first particle size distribution.    
   
   
       10 . A chemical-mechanical polishing method, comprising: 
 delivering first polishing product containing particles having a first particle size distribution to a chemical-mechanical polishing machine;    polishing with the first polishing product to remove a first thicknesses of material from the surface of a part to be treated;    next delivering polishing product containing particles having a second particle size distribution to the chemical-mechanical polishing machine; and    polishing with the second polishing product to remove a second thicknesses of material from the surface of a part to be treated.    
   
   
       11 . The method of  claim 10  wherein the second thickness is less than the first thickness.  
   
   
       12 . The method of  claim 10  further comprising: 
 sourcing a polishing product containing particles having the first particle size distribution for use as the first polishing product; and    filtering the sourced polishing product containing particles having the first particle size distribution to produce the second polishing product.    
   
   
       13 . The method of  claim 10  wherein the second particle size distribution differs from the first particle size distribution in that the second particle size distribution does not include relatively larger sized particles which are contained in the first particle size distribution.