Method for locating an alignment feature of a crystalline body

Abstract

The method and apparatus of the present invention permit indirect identification of a target plane, such as the plane identified by an alignment feature, based upon the identification of a reference plane which is offset by a predetermined angle from the target plane. In addition, in order to permit alignment features to be defined at non-standard angles with respect to the axial orientation of an ingot, an apparatus is provided that includes a frame having at least two members. The first member abuts a bar extending outwardly from the stage of an x-ray diffractometer, while the second member carries an engagement member for engaging a non-standard alignment feature. The second member may be movable relative to the first member to permit the frame to be mounted upon ingots having different non-standard alignment features.

That which is claimed:  
     
         1 . A method of verifying a location of an alignment feature of a crystalline body, the method comprising: 
 analyzing radiation returned from the crystalline body, wherein analyzing the radiation comprises identifying a reference plane defined by the crystalline body based upon the returned radiation;    locating a target plane based upon the identification of the reference plane and a predefined angular offset between the reference plane and the target plane; and    determining a positional relationship between the target plane and the alignment feature.    
     
     
         2 . A method according to  claim 1  further comprising determining that the alignment feature is located properly by determining that any angular offset between the alignment feature and the target plane is less than a predetermined threshold.  
     
     
         3 . A method according to  claim 1  further comprising determining the predefined angular offset between the reference plane and the target plane prior to locating the target plane.  
     
     
         4 . A method according to  claim 1  further comprising: 
 impinging radiation upon the crystalline body; and  
 detecting the radiation returning from the crystalline body prior to analyzing the returned radiation.  
 
     
     
         5 . A method according to  claim 4  wherein impinging radiation upon the crystalline body comprises impinging radiation upon the crystalline body at a plurality of incidence angles, and wherein identifying the reference plane comprises identifying the incidence angle of the impinging radiation at which radiation having the greatest power is detected.  
     
     
         6 . A method of analyzing a crystalline body to define an initial alignment feature, the method comprising: 
 analyzing radiation returned from the crystalline body, wherein analyzing the radiation comprises identifying a reference plane defined by the crystalline body based upon the returned radiation;    locating a target plane based upon the identification of the reference plane and a predefined angular offset between the reference plane and the target plane; and    forming the initial alignment feature upon the crystalline body to identify the target plane.    
     
     
         7 . A method according to  claim 6  further comprising determining the predefined angular offset between the reference plane and the target plane prior to locating the target plane.  
     
     
         8 . A method according to  claim 6  further comprising: 
 impinging radiation upon the crystalline body; and  
 detecting the radiation returning from the crystalline body prior to analyzing the returned radiation.  
 
     
     
         9 . A method according to  claim 8  wherein impinging radiation upon the crystalline body comprises impinging radiation upon the crystalline body at a plurality of incidence angles, and wherein identifying the reference plane comprises identifying the incidence angle of the impinging radiation at which radiation having the greatest power is detected.