Wafer polishing apparatus, wafer polishing system and wafer polishing method

Abstract

It is possible to execute a one-step polishing or a plural-step polishing at a high throughput, and it is possible to achieve a reduction of an occupied area on the basis of a compact structure of a whole apparatus. Two platens are respectively provided with a first wafer retention head and a second wafer retention head, and a wafer transfer apparatus on which a wafer is mounted is arranged between two platens. The two wafer retention heads are moved between two platens and the wafer transfer apparatus respectively by a first moving means and a second moving means. Further, a two-step polishing is executed by whirl moving two wafer retention heads from one platen to the other platen at 180 degree respectively by a whirl moving means supporting two moving means.

1 . A wafer polishing apparatus that polishes a wafer by pressing the wafer retained by a wafer retention head to a polishing pad on a platen, comprising:
 a first platen and a second platen provided in parallel while having a gap from each other;   a first wafer retention head and a second wafer retention head respectively installed above the first platen and the second platen and being movable up and down;   a wafer transfer apparatus arranged between the first platen and the second platen and on which the wafer before being polished and the wafer after being polished are mounted;   a first moving means that moves and stops the first wafer retention head to both positioning portions of the first platen and the wafer transfer apparatus;   a second moving means that moves and stops the second wafer retention head to both positioning portions of the second platen and the wafer transfer apparatus; and   a third moving means that supports the first moving means and the second moving means, and whirls around the wafer transfer apparatus so as to move and stop the first wafer retention head and the second wafer retention head respectively to the positioning portions of the second platen and the first platen,   wherein the wafer polished by the first platen or the second platen is whirled and moved to the positioning portion of the second platen or the first platen so as to be polished.   
     
     
         2 . A wafer polishing apparatus that polishes a wafer by pressing the wafer retained by a wafer retention head to a polishing pad on a platen, comprising:
 a first platen and a second platen provided in parallel while having a gap from each other;   a first wafer retention head and a second wafer retention head respectively installed above the first platen and the second platen and being movable up and down;   a wafer transfer apparatus arranged between the first platen and the second platen and on which the wafer before being polished and the wafer after being polished are mounted;   a first moving means that moves and stops the first wafer retention head to both positioning portions of the first platen and the wafer transfer apparatus;   a second moving means that moves and stops the second wafer retention head to both positioning portions of the second platen and the wafer transfer apparatus; and   a third moving means that supports the first moving means and the second moving means, and whirls around the wafer transfer apparatus so as to move and stop the first wafer retention head and the second wafer retention head respectively to the positioning portions of the second platen and the first platen,   wherein the wafer polished by the first platen or the second platen is whirled and moved to the positioning portion of the second platen or the first platen so as to be polished, a partition wall for preventing a liquid from flying in all directions is provided between the first platen and the wafer transfer apparatus, and between the second platen and the wafer transfer apparatus, a passage through which the first wafer retention head and the second wafer retention head pass is formed in the partition wall, and the partition wall is provided in such a manner as to be capable of integrally whirling with the third moving means.   
     
     
         3 . The wafer polishing apparatus as claimed in  claim 1  or  2 , wherein the wafer transfer apparatus is provided with a wafer carry-in means that carries in the unpolished wafer, and a wafer carry-out means that carries out the polished wafer, and the wafer carry-out means and the wafer carry-in means are structured such as to be independently movable to a position corresponding to a center position of whirling of the third moving means. 
     
     
         4 . The wafer polishing apparatus according to  claim 1 ,  2  or  3 , wherein the third moving means is provided so as to be retractable from the center position of whirling, and a head cleaning apparatus for cleaning the first wafer retention head and the second wafer retention head is installed at the center position of whirling. 
     
     
         5 . The wafer polishing system provided with the wafer polishing apparatus according to  claim 1  or  2 , wherein two or more the wafer polishing apparatuses are provided in parallel, and a transfer apparatus for transferring the wafer polished by one wafer polishing apparatus to the other wafer polishing apparatus installed in adjacent thereto is provided between the adjacent wafer polishing apparatuses. 
     
     
         6 . The wafer polishing method of polishing a wafer by the wafer polishing system according to  claim 5  in which two wafer polishing apparatuses are provided in parallel, comprising:
 a step of transferring the wafer to one of two wafer polishing apparatuses so as to execute a one-step polishing or a two-step polishing;   a step of transferring the wafer executed the one-step polishing or the two-step polishing to the other wafer polishing apparatus by a transfer apparatus; and   a step of further applying the one-step polishing or the two-step polishing to the wafer by the other wafer polishing apparatus,   wherein a three-step polishing or a four-step polishing is applied as a whole to the wafer.