Method for monitoring a CMP polishing method and arrangement for a CMP polishing method

Abstract

The invention relates to a method for monitoring a CMP polishing method, a substrate being fixed in a mount, a polishing pad being fixed on a plate, a surface of the polishing pad being operatively connected to a surface of the substrate, the polishing pad and the substrate being moved relative to one another, so that material is removed from the surface of the substrate. A measuring device is provided, which is operatively connected to the surface of the polishing pad, the measuring device detecting the surface constitution of the polishing pad and generating a measurement signal dependent on the surface constitution of the polishing pad. The measurement signal is compared with corresponding reference values for the purpose of identifying a change in the material of the surface of the substrate during the CMP polishing method.

1 . A method for monitoring a CMP polishing method, comprising: 
 fixing a substrate in a mount;    fixing a polishing pad on a plate, a surface of the polishing pad operatively connected to a surface of the substrate;    moving the polishing pad and the substrate relative to one another, so that material is removed from the surface of the substrate;    providing a measuring device, which is operatively connected to the surface of the polishing pad; and    generating a measurement signal dependent on the surface constitution of the polishing pad, using the measuring device    wherein the measurement signal is used for identifying a change in the material of the surface of the substrate during the CMP polishing method.    
   
   
       2 . The method as claimed in  claim 1 , wherein the measuring device detects a force effect between the polishing pad and the measuring device.  
   
   
       3 . The method as claimed in  claim 1 , wherein the measuring device detects a friction effect between the polishing pad and the measuring device.  
   
   
       4 . The method as claimed in one of claims  1 , wherein a defined change in the measurement signal is identified as a change in the surface material of the substrate.  
   
   
       5 . The method as claimed in one of claims  1 , wherein the measurement signal and/or a change in the measurement signal is compared with a reference value, and wherein a material change in the surface of the substrate is identified depending on the comparison.  
   
   
       6 . The method as claimed in one of claims  1 , wherein the measurement signal and/or the change in the measurement signal is compared with a reference value corresponding to an end point of the CMP process, and wherein in the event of the measurement signal and/or the change in the measurement signal matching the reference signal, an end point for the CMP process is identified and the CMP process is ended.  
   
   
       7 . An arrangement for carrying out a CMP polishing method, comprising: 
 a substrate mount for holding a substrate;    a polishing pad mount for holding a polishing pad;    a drive, by means of which the substrate mount and the polishing pad mount can be moved relative to one another, the substrate mount and the polishing pad mount being formed that the polishing pad can be operatively connected to a surface of the substrate;    a measuring device, which can be operatively connected to the polishing pad, the measuring device having a sensor, by means of which the surface constitution of the polishing pad can be detected, the measuring device configured to generate a measurement signal dependent on the surface constitution of the polishing pad; and    an evaluation unit is provided, which is connected to the sensor, wherein the evaluation unit is connected to a data memory, reference values for the measurement signal of the sensor, which are assigned to a surface constitution of the substrate, are stored in the data memory,    the measurement signal can be fed to the evaluation unit, and the evaluation unit is designed to identify a surface constitution and/or a surface change of the substrate by way of a comparison between the measurement signal and a reference value.    
   
   
       8 . The arrangement as claimed in  claim 7 , wherein the sensor detects a friction value between the polishing pad and the measuring device, and the evaluation unit identifies a surface constitution and/or a surface change of the substrate from the friction value and the corresponding reference value stored in the data memory.  
   
   
       9 . The arrangement as claimed in  claim 7 , wherein 
 the measuring device detects, as measurement signal, a change in the friction between the polishing pad and the measuring device, and    the evaluation unit is designed to identify a surface constitution and/or a surface change of the substrate from the change in the friction and the corresponding reference value stored in the data memory.    
   
   
       10 . The arrangement as claimed in  claim 7 , wherein 
 reference values for the measurement signal, which correspond to an end point of the CMP process, are stored in the data memory,    the evaluation unit is connected to the drive of the substrate and polishing pad mounts, and    the evaluation unit is designed to identify an end point for the CMP process on account of the comparison between the measurement signal and the reference value and to end the CMP process.    
   
   
       11 . A method for monitoring a CMP polishing method, comprising: 
 fixing a substrate in a mount;    fixing a polishing pad on a plate;    operatively connecting a surfaced of the polishing pad to a surface of the substrate, the polishing pad and the substrate being moved relative to one another, so that material is removed from the surface of the substrate;    providing a measuring device, which is operatively connected to the surface of the polishing pad, the measuring device generating a measurement signal dependent on the surface constitution of the polishing pad, the measurement signal being used for identifying a change in the material of the surface of the substrate during the CMP polishing method, wherein the measuring device detects a force effect or a friction effect between the polishing pad and the measuring device.    
   
   
       12 . An arrangement for carrying out a CMP polishing method, comprising: 
 a substrate mount for holding a substrate;    a polishing pad mount for holding a polishing pad;    a drive, by means of which the substrate mounts and the polishing pad mount can be moved relative to one another, the substrate mount and the polishing pad mount being formed that the polishing pad can be operatively connected to a surface of the substrate;    a measuring device, which can be operatively connected to the polishing pad, the measuring device having a sensor, by means of which the surface constitution of the polishing pad can be detected, the measuring device configured to generate a measurement signal dependent on the surface constitution of the polishing pad; an evaluation unit, which is connected to the sensor, wherein the evaluation unit is connected to a data memory,    reference values for the measurement signal of the sensor, which are assigned to a surface constitution of the substrate, are stored in the data memory, the measurement signal can be fed to the evaluation unit, and    the evaluation unit is designed to identify a surface constitution and/or a surface change of the substrate by way of a comparison between the measurement signal and a reference value,    the sensor detects, as measurement signal, a friction value between the polishing pad and the measuring device, and    the evaluation unit identifies a surface constitution and/or a surface change of the substrate from the friction value and the corresponding reference value stored in the data memory.