Wafer polishing head

Abstract

A wafer polishing head according to the invention is disclosed. In the wafer polishing head, an automatic control device is additionally installed outside the wafer polishing head for automatically adjusting a pressure applied on a retaining ring. This ensures the bottom of the retaining ring always lower than that of a carrier, thereby preventing a semiconductor wafer from slip during polishing. Furthermore, a liquid pressure generated to press the carrier can efficiently alleviate wabble during polishing. Therefore, the wafer polishing head of the invention can greatly improve a polishing uniformity.

1 . A wafer polishing head for planarizing a wafer comprising a carrier for loading the wafer, a wafer adhering layer disposed beneath the carrier, a retaining ring surrounding the carrier and the wafer adhering layer, the wafer polishing comprising: 
 a first pressure chamber having a first inner pressure disposed above the retaining ring;    a second pressure chamber having a second inner pressure disposed on the carrier; and    an automatic control system respectively coupled to the first pressure chamber and the second pressure chamber for adjusting a relative height between the carrier and the retaining ring.    
     
     
         2 . A wafer polishing head for planarizing a wafer comprising a carrier for loading the wafer, a wafer adhering layer disposed beneath the carrier, a retaining ring surrounding the carrier and the wafer adhering layer, the wafer polishing comprising: 
 a first pressure chamber having a first inner pressure disposed above the retaining ring; and    a second pressure chamber having a second inner pressure disposed on the carrier, wherein a relative height between the retaining ring and the carrier can be adjusted by changing the first and second inner pressure.    
     
     
         3 . A wafer polishing head for planarizing a wafer comprising a carrier for loading the wafer, a wafer adhering layer disposed beneath the carrier, a retaining ring surrounding the carrier, the wafer adhering layer, a first pressure chamber having a first inner pressure disposed above the retaining ring, and a second pressure chamber having a second inner pressure disposed on the carrier, the wafer polishing comprising: 
 an automatic control system respectively coupled to the first pressure chamber and the second pressure chamber for adjusting a relative height between the carrier and the retaining ring.