Pad surface texture formed by solid phase droplets

Abstract

A polishing pad is made by a piezoelectric delivery system, and a method of making the pad includes, building successive layers of droplets of material one layer on another layer by dispensing the material in fluid phase as droplets arranged in a droplet pattern, and solidifying the droplets in the droplet pattern to provide the polishing surface with a surface texture having recesses bounded by the droplets in the droplet pattern.

What is claimed is:  
     
         1 . A process for making polishing pads useful in the manufacture of a semiconductor device or a precursor thereto, comprising applying a material comprising a hydrophilic polymer and abrasive to a flexible base substrate using a piezoelectric material delivery system to form a polishing layer on the substrate and curing the deposited polishing layer.  
     
     
         2 . The process of    claim 1    in which a multiplicity of layers are applied to a desired pattern and thickness to form the polishing layer and the layer is cured thermally or with a laser.  
     
     
         3 . The process of    claim 2    in which the piezoelectric material delivery system comprises a piezoelectric printer.  
     
     
         4 . A method for making a polishing surface on a polishing pad, comprising the steps of: building successive layers of droplets of material one layer on another layer by dispensing the material in fluid phase as droplets arranged in a droplet pattern, and solidifying the droplets in the droplet pattern to provide the polishing surface with a surface texture having recesses bounded by the droplets in the droplet pattern.  
     
     
         5 . The method of    claim 4    wherein, the step of building successive layers of material further comprises the step of: dispensing the material in fluid phase as droplets of different sizes.  
     
     
         6 . The method of    claim 4    wherein, the step of dispensing the material in fluid phase as droplets, further comprises the step of; dispensing the material in fluid phase as droplets of polymeric material in a solvent of the polymeric material.  
     
     
         7 . The method of    claim 4    wherein, the step of building successive layers of material further comprises the step of, dispensing particulates in suspension with the material in fluid phase; and the step of solidifying the droplets in the droplet pattern further comprises the step of, solidifying the droplets in the droplet pattern to retain the particulates in the droplets.  
     
     
         8 . The method of    claim 4    wherein, the step of solidifying the droplets in the droplet pattern further comprises the step of curing the droplets.  
     
     
         9 . A polishing surface on a polishing pad comprising: successive layers of droplets of material, the droplets being arranged in a pattern of solidified droplets in each of the layers, and a surface texture of the polishing surface provided by recesses bounded by the droplets arranged in the pattern of droplets.  
     
     
         10 . A system for making a polishing surface on a polishing pad comprising: a reservoir supplying solidifyable material of fluid phase to a computer controlled piezoelectric printer, a printer head of the printer dispensing droplets of the material in a pattern of droplets onto a substrate of a polishing pad, and a curing apparatus curing the droplets to solid phase to retain the droplets in the pattern.