Polishing machine and a polishing method for a substrate

Abstract

One object is to provide a polishing machine and a polishing method capable of improving a processing accuracy on the surface of an object. A method of polishing an object is provided. Such a method comprises: a first step of polishing an object by moving the object and a first polishing pad having a smaller dimension than that of the object relative to each other while the first polishing pad is made to contact the object, a second step of polishing the object, after the first step of polishing, by moving the object and a second polishing pad having a larger dimension than that of the object relative to each other while the second polishing pad is made to contact the object, and a step of detecting the state of the surface of the object before the first step of polishing.

What is claimed is: 
     
         1 . A method of polishing an object, the method comprising the steps of:
 first polishing the object by moving the object and a first polishing pad having a smaller dimension than that of the object relative to each other while the first polishing pad is made to contact the object,   second polishing the object, after the first polishing, by moving the object and a second polishing pad having a larger dimension than that of the object relative to each other while the second polishing pad is made to contact the object, and   detecting the state of a surface of the object before the first polishing.   
     
     
         2 . The method according to  claim 1 , comprising the step of:
 determining a processing condition for the first polishing based on the detected state of the surface of the object.   
     
     
         3 . The method according to  claim 1 , wherein
 the step of detecting the state of the surface comprises a step of detecting at least one distribution of a film thickness of the surface of the object, a signal corresponding to the film thickness and a signal corresponding to a surface shape.   
     
     
         4 . A polishing machine for polishing an object, the polishing machine comprising:
 a detector for detecting the state of a surface of the object,   a first polishing module for performing a first step of polishing by moving the object and a first polishing pad having a smaller dimension than that of the object relative to each other while the first polishing pad is made to contact the object,   a second polishing module for performing a second step of polishing by moving the object and a second polishing pad having a larger dimension than that of the object relative to each other while the second polishing pad is made to contact the object, and   a control device for controlling the first polishing module and the second polishing module, wherein   the control device controls so that the second step of polishing is performed after the first step of polishing, and   the detector detects the state of the surface of the object before the first step of polishing.   
     
     
         5 . The polishing machine according to  claim 4 , wherein
 the control device is configured to determine a polishing condition for the first step of polishing based on the state of the surface detected by the detector.   
     
     
         6 . The polishing machine according to  claim 4 , comprising:
 a storage device for storing data about the state of the surface that is a target to the object, wherein   the control device for determining a polishing condition for the first step of polishing and a polishing condition for the second step of polishing based on the data stored in the storage device and the state of the surface detected by the detector.   
     
     
         7 . A non transitory computer readable medium that records a program for controlling an operation of a polishing machine for polishing an object, the program configured to control the polishing machine to execute:
 a first step of polishing the object by moving the object and a first polishing pad having a smaller dimension than that of the object relative to each other while the first polishing pad is made to contact the object,   a second step of polishing, after the first step of polishing, the object by moving the object and a second polishing pad having a larger dimension than that of the object relative to each other while the second polishing pad is made to contact the object, and   a step of detecting the state of the surface of the object before the first step of polishing.   
     
     
         8 . The non transitory computer readable medium according to  claim 7 , configured to control the polishing machine to execute:
 a step of determining a processing condition for the first step of polishing based on the detected state of the surface of the object.   
     
     
         9 . The non transitory computer readable medium according to  claim 7 , configured to control the polishing machine to execute:
 a step of determining a processing condition for the first polishing based on the data of removal rate against polish condition stored in a database.   
     
     
         10 . The non transitory computer readable medium according to  claim 7 , wherein
 the step of detecting the state of the surface controls the polishing machine to execute a step of detecting at least one distribution of a film thickness of the surface of the object, a signal corresponding to the film thickness and a signal corresponding to a surface shape.   
     
     
         11 . A polishing module for polishing an object, the polishing module comprising:
 a rotatable polishing head,   a polishing pad held by the polishing head,   a rotatable stage for holding the object,   a polishing solution supply device for supplying a polishing solution over the surface of the object,   an actuator configured to apply a pressing force to the surface of the object by the polishing pad,   a positioning mechanism configured to movably control a contact position of the polishing pad on the object, and   a pad conditioning device disposed to be on the approximately same plane or an approximately parallel plane to the surface of the object held by the stage, wherein   the pad conditioning device is configured to be able to move relative to the polishing pad.   
     
     
         12 . The polishing module according to  claim 11 , wherein the polishing pad has a diameter not greater than 30 mm. 
     
     
         13 . The polishing module according to  claim 11 , wherein
 the polishing pad is held by the polishing head via a cushion layer softer than a surface layer in contact with the object.   
     
     
         14 . The polishing module according to  claim 11 , wherein
 the polishing head is configured so that the surface of the polishing pad is vertical to an axis of rotation of the polishing head.   
     
     
         15 . The polishing module according to  claim 11 , wherein
 an angle between an axis vertical to the surface of the object and the axis of rotation of the polishing head of the polishing head is greater than 0 degree.   
     
     
         16 . The polishing module according to  claim 11 , wherein
 the axis of rotation of the polishing head is substantially parallel to the surface of the object,   the polishing pad has a diameter larger than that of the polishing head, and   the center of the polishing pad is the same as the axis of rotation of the polishing head.   
     
     
         17 . The polishing module according to  claim 11 , wherein
 an opening is formed in the central portion of the polishing pad, and   the polishing solution supply device is configured to supply a polishing solution to the surface of the object through the opening of the polishing pad.   
     
     
         18 . The polishing module according to  claim 11 , comprising:
 an XY stage fixed to the stage and configured to be able to move the object straightly.   
     
     
         19 . The polishing module according to  claim 11 , wherein:
 the stage is configured to be able to stop at an arbitrary rotational position, and   the polishing head is connected to a linear-moving mechanism passing through the center of the object.   
     
     
         20 . The polishing module according to  claim 11 , wherein:
 the stage is configured to be able to stop at an arbitrary rotational position, and   the polishing head is connected to a swing mechanism passing along a circular path that passes through the center of the object.