Method and apparatus for on the fly positioning and continuous monitoring of a substrate in a chamber

Abstract

A method and apparatus for positioning a substrate in a substrate processing chamber. The method includes placing the substrate on a substrate transfer blade, moving the substrate transfer blade to a first position located in a transfer chamber, and capturing at least one image that includes at least a portion of the substrate transfer blade and at least a portion of the substrate. The method also includes processing the image to determine a position of a predetermined portion of the substrate transfer blade and a position of predetermined portion of the substrate. The method further includes determining an offset between the position of the predetermined portion of the substrate transfer blade and the position of the predetermined portion of the substrate, and moving the substrate transfer blade to a second position located in the substrate processing chamber, wherein the second position is adjusted to account for the offset.

1 . A method of positioning a substrate in a substrate processing chamber, the method comprising: 
 placing the substrate on a substrate transfer blade;    moving the substrate transfer blade to a first position located in a transfer chamber;    capturing at least one image that comprises at least a portion of the substrate transfer blade and at least a portion of the substrate; and    processing the at least one image to determine a position of a predetermined portion of the substrate transfer blade and a position of predetermined portion of the substrate;    determining an offset between the position of the predetermined portion of the substrate transfer blade and the position of the predetermined portion of the substrate;    moving the substrate transfer blade to a second position located in the substrate processing chamber, wherein the second position is adjusted to account for the offset.    
   
   
       2 . The method of  claim 1  wherein the predetermined portion of the substrate transfer blade is a center of the substrate transfer blade.  
   
   
       3 . The method of  claim 1  wherein the predetermined portion of the substrate is a center of the substrate.  
   
   
       4 . The method of  claim 3  wherein the substrate is a semiconductor wafer.  
   
   
       5 . The method of  claim 1  wherein the second position is a position in which the wafer is centered with respect to the substrate transfer blade.  
   
   
       6 . The method of  claim 1  wherein the step of processing the at least one image comprises the steps of: 
 identifying at least one fiducial mark;    calculating a location of the predetermined portion of the substrate transfer blade based on the location of the at least one fiducial mark;    identifying an outer edge of the substrate; and    calculating a location of the predetermined portion of the substrate.    
   
   
       7 . The method of  claim 6  wherein the predetermined portion of the substrate transfer blade is a center of the substrate transfer blade and the predetermined portion of the substrate is a center of the substrate.  
   
   
       8 . The method of  claim 7  wherein the at least one fiducial mark is fabricated on a peripheral edge of the substrate transfer blade.  
   
   
       9 . The method of  claim 8  wherein the at least one fiducial marks are three fiducial marks located at a distance of less than 8 mm from a peripheral edge of the substrate.  
   
   
       10 . The method of  claim 7  wherein the at least one fiducial mark is a geometric shape characterized by an optical reflectivity greater than a portion of the wafer transfer blade.  
   
   
       11 . The method of  claim 7  wherein the at least one fiducial mark is a geometric shape characterized by an optical reflectivity less than a portion of the wafer transfer blade.  
   
   
       12 . An apparatus for positioning a substrate in a substrate processing chamber, the apparatus comprising: 
 a transfer blade coupled to a robotic assembly and adapted to support a substrate;    an optical assembly adapted to capture an image comprising at least a portion of the transfer blade and at least a portion of the substrate; and    a computational device programmed to calculate the position of the substrate relative to the transfer blade.    
   
   
       13 . The apparatus of  claim 12  further comprising: 
 a plurality of fiducial marks associated with the transfer blade, wherein the computational device utilizes the plurality of fiducial marks in calculating the position of the substrate relative to the transfer blade.    
   
   
       14 . The apparatus of  claim 13  wherein the plurality of fiducial marks are fabricated on a peripheral edge of the transfer blade.  
   
   
       15 . The apparatus of  claim 14  wherein the plurality of fiducial marks are at least three fiducial marks located at a distance of less than  8  mm from a peripheral edge of the substrate.  
   
   
       16 . The apparatus of  claim 12  wherein the substrate is a semiconductor wafer.  
   
   
       17 . A method for positioning a substrate in a substrate processing chamber, the method comprising: 
 providing a substrate support disposed in the substrate processing chamber;    providing a plurality of fiducial marks disposed on at least one component of the substrate processing chamber;    placing a substrate on the substrate support;    capturing an image comprising at least one of the plurality of fiducial marks disposed on the at least one component of the substrate processing chamber and at least a portion of the substrate;    determining an offset between a predetermined position of the substrate support and a predetermined position of the substrate; and    repositioning the substrate on the substrate support in response to the offset.    
   
   
       18 . The method of  claim 17  wherein the plurality of fiducial marks are structural features of the at least one component of the substrate processing chamber.  
   
   
       19 . The method of  claim 17  wherein the fiducial marks are geometric shapes located on the at least one component of the substrate processing chamber.  
   
   
       20 . A method for positioning a substrate in a substrate processing chamber, the method comprising: 
 providing a substrate support disposed in the substrate processing chamber;    providing a plurality of fiducial marks disposed on the substrate support;    placing a substrate on the substrate support;    capturing a first image comprising at least one of the plurality of fiducial marks disposed on the substrate support and at least a portion of the substrate;    determining an offset between a predetermined position of the substrate support and a predetermined position of the substrate; and    repositioning the substrate on the substrate support in response to the offset.    
   
   
       21 . The method of  claim 20  wherein the fiducial marks are geometric patterns located on the substrate support.  
   
   
       22 . The method of  claim 21  further comprising: 
 placing an integrated calibration field on the substrate support;    capturing a calibration image comprising at least a portion of the integrated calibration field;    creating a mapping based on the calibration image; and    calibrating the first image based on the mapping.    
   
   
       23 . An apparatus for positioning a substrate in a substrate processing chamber, the apparatus comprising: 
 a substrate support disposed in the processing chamber;    an optical system adapted to capture an image comprising at least a portion of the substrate support and a portion of a substrate supported by the substrate support;    a computational device adapted to calculate a position of a predetermined portion of the substrate relative to the substrate support; and    a transfer blade adapted to reposition the substrate in response to the calculation produced by the computational device.    
   
   
       24 . The apparatus of  claim 23  further comprising: 
 at least one fiducial mark associated with the substrate support, wherein the computational device utilizes the at least one fiducial mark in calculating the position of the predetermined portion of the substrate relative to the substrate support.