Polishing pad wear detecting apparatus

Abstract

A polishing pad wear detecting apparatus suitable for a chemical mechanical polishing (CMP) apparatus is provided. The polishing pad wear detecting apparatus includes an arm and a height detector. One end of the arm is fastened on the CMP apparatus. The height detector is disposed on the arm for detecting height variation of a polishing pad.

1 . A polishing pad wear detecting apparatus, suitable for a chemical mechanical polishing (CMP) apparatus, the polishing pad wear detecting apparatus comprising:
 an arm, wherein one end of the arm is fastened on the CMP apparatus; and   a height detector, disposed on the arm, for detecting a height variation of a polishing pad.   
     
     
         2 . The polishing pad wear detecting apparatus according to  claim 1 , wherein the arm is fastened on the CMP apparatus through pivoting to allow the arm to scan above the polishing pad. 
     
     
         3 . The polishing pad wear detecting apparatus according to  claim 1 , wherein a length of the arm allows the height detector to be located above a central spot of the polishing pad. 
     
     
         4 . The polishing pad wear detecting apparatus according to  claim 1 , wherein a material of the arm comprises a rigid material. 
     
     
         5 . The polishing pad wear detecting apparatus according to  claim 1 , wherein the height detector comprises a non-contact height detector or a contact height detector. 
     
     
         6 . The polishing pad wear detecting apparatus according to  claim 5 , wherein the non-contact height detector comprises an electromagnetic impedance detecting device, a laser transmitting and receiving device, or an ultrasound transmitting and receiving device. 
     
     
         7 . The polishing pad wear detecting apparatus according to  claim 5 , wherein the contact height detector comprises a stylus device.