High speed injection nozzle for pre-polish modification of substrate thickness

Abstract

A method of fabrication of a substrate includes, after deposition of an outer layer on a substrate and before polishing of an exposed surface of the outer layer of the substrate, performing a hydroblasting treatment of a selected portion of the exposed surface by directing a treatment liquid from a nozzle at a sufficiently high velocity onto the selected portion to remove material from the selected portion such that a thickness non-uniformity of the outer layer is reduced. Then the outer layer of the treated substrate is subject to chemical mechanical polishing to planarize and reduce a thickness of the outer layer.

What is claimed is: 
     
         1 . A method comprising:
 after deposition of an outer layer on a substrate and before polishing of an exposed surface of the outer layer of the substrate, performing a hydroblasting treatment of a selected portion of the exposed surface by directing a treatment liquid from a nozzle at a sufficiently high velocity onto the selected portion to remove material from the selected portion such that a thickness non-uniformity of the outer layer is reduced; and   chemical mechanical polishing the outer layer of the treated substrate to planarize and reduce a thickness of the outer layer.   
     
     
         2 . The method of  claim 1 , comprising depositing the outer layer at a deposition station, and transferring the substrate to a hydroblasting treatment station for the hydroblasting treatment. 
     
     
         3 . The method of  claim 1 , comprising holding the substrate on a chuck during the hydroblasting treatment. 
     
     
         4 . The method of  claim 3 , comprising holding the substrate in a face-up orientation during the hydroblasting treatment. 
     
     
         5 . The method of  claim 3 , comprising holding the substrate in a face-down orientation during the hydroblasting treatment. 
     
     
         6 . The method of  claim 3 , comprising vacuum chucking the substrate to a chuck. 
     
     
         7 . The method of  claim 3 , comprising rotating the chuck and sweeping the nozzle radially across the substrate to position the nozzle over the selected portion. 
     
     
         8 . The method of  claim 1 , wherein the treatment fluid comprises deionized (DI) water. 
     
     
         9 . The method of  claim 8 , wherein the treatment fluid is free of abrasives and/or etchants. 
     
     
         10 . The method of  claim 1 , wherein the selected portion is annular. 
     
     
         11 . The method of  claim 10 , wherein the selected portion has a radial width of about 5 to 40 mm. 
     
     
         12 . The method of  claim 1 , comprising flowing the treatment fluid at a velocity of 5-20 m/s onto the exposed surface of the substate. 
     
     
         13 . The method of  claim 1 , comprising receiving a measured thickness profile of the outer layer from a metrology station, storing a desired thickness profile, and comparing the measured thickness profile to the desired thickness profile to determine the selected portion of the surface. 
     
     
         14 . A hydroblasting treatment station for modification of a substrate undergoing integrated circuit fabrication, the station comprising:
 a chuck to hold the substrate;   a nozzle coupled to a source of treatment liquid, the nozzle laterally movable relative to the substrate; and   a controller configured to cause the nozzle to direct the treatment liquid at a sufficiently high velocity onto the selected portion to remove material from the selected portion such that a thickness non-uniformity of an outer layer of the substrate is reduced.   
     
     
         15 . The hydroblasting treatment station of  claim 14 , comprising a shield to catch treatment fluid flung or dropping from the substrate. 
     
     
         16 . The hydroblasting treatment station of  claim 14 , comprising a plurality of passages through the chuck that are coupled to a vacuum source to vacuum chuck the substrate to the chuck. 
     
     
         17 . The hydroblasting treatment station of  claim 14 , wherein the controller is configured to receive a measured thickness profile of the outer layer from a metrology station, store a desired thickness profile, and compare the measured thickness profile to the desired thickness profile to determine the selected portion of the surface. 
     
     
         18 . The hydroblasting treatment station of  claim 14 , comprising a pump or valve to control a flow rate of treatment liquid from the source to the nozzle. 
     
     
         19 . The hydroblasting treatment station of  claim 18 , wherein the controller is configured to control the pump or valve such that the treatment liquid is ejected at a velocity of 5-20 m/s onto the exposed surface of the substate. 
     
     
         20 . The hydroblasting treatment station of  claim 14 , wherein the chuck is rotatable. 
     
     
         21 . The hydroblasting treatment station of  claim 20 , wherein the nozzle is suspended from a pivotable arm.