Formation of dielectric with smooth surface

Abstract

Embodiments of the present disclosure are directed towards techniques and configurations for formation of a dielectric with a smooth surface. In one embodiment, a method includes providing a dielectric with first and second surfaces, a conductive feature formed on the first surface, and a laminate applied to the second surface, curing the second surface while the laminate remains applied, and removing the laminate. Other embodiments may be described and/or claimed.

What is claimed is: 
     
         1 . A method, comprising:
 providing a dielectric with first and second surfaces, a conductive feature formed on the first surface, and a laminate applied to the second surface;   curing the second surface while the laminate remains applied; and   removing the laminate.   
     
     
         2 . The method of  claim 1 , further comprising depositing a metal layer onto the second surface using a physical vapor deposition (PVD) process. 
     
     
         3 . The method of  claim 2 , wherein:
 the PVD process includes sputtering or evaporation; and   the metal layer comprises a seed layer.   
     
     
         4 . The method of  claim 1 , further comprising:
 forming a via from the second surface through the dielectric to the conductive feature; and   chemically desmearing the via.   
     
     
         5 . The method of  claim 4 , wherein the drilling and desmearing are performed while the laminate remains applied to the second surface. 
     
     
         6 . The method of  claim 4 , further comprising applying a surface masking layer to the second surface after the laminate is removed. 
     
     
         7 . The method of  claim 6 , wherein the drilling and desmearing are performed while the surface masking layer remains applied to the second surface. 
     
     
         8 . The method of  claim 1 , further comprising curing the second surface again after the laminate is removed. 
     
     
         9 . The method of  claim 1 , wherein the conductive feature is a first conductive feature, the method further comprising forming a second conductive feature by depositing an electrically conductive material to fill the via, the second conductive feature being electrically coupled with the first conductive feature. 
     
     
         10 . The method of  claim 9 , wherein the second conductive feature is formed using an additive process. 
     
     
         11 . The method of  claim 9 , wherein the second conductive feature is formed using a subtractive process. 
     
     
         12 . A product formed by the method of  claim 1 . 
     
     
         13 . A package substrate comprising:
 a dielectric having a first surface and a second surface disposed opposite to the first surface;   a conductive feature formed on the first surface; and   a via that extends from the second surface through the dielectric to the conductive feature;   wherein the second surface has a surface roughness between 40 nanometers and 75 nanometers, the second surface is shaped at least in part by a surface of a previously-applied laminate, and the dielectric includes a polymer.   
     
     
         14 . The package substrate of  claim 13 , wherein the conductive feature is a first conductive feature, the via is filled with conductive material, and the package substrate further comprises a second conductive feature formed on the second surface and coupled with the first conductive feature. 
     
     
         15 . The package substrate of  claim 13 , wherein the dielectric comprises an epoxy-based Ajinomoto build-up film (“ABF”). 
     
     
         16 . The package substrate of  claim 13 , wherein surface roughness is an average roughness, R a , calculated using the following equation: 
       
         
           
             
               
                 R 
                 a 
               
               = 
               
                 
                   1 
                   n 
                 
                  
                 
                   
                     ∑ 
                     
                       i 
                       = 
                       1 
                     
                     n 
                   
                    
                   
                      
                     
                       y 
                       i 
                     
                      
                   
                 
               
             
           
         
         wherein n is a positive integer that represents a number of surface samples measured, and y is a distance of a sample from a mean line of the surface. 
       
     
     
         17 . A system comprising:
 a die; and   a package substrate coupled to the die, the package substrate comprising:
 a dielectric having a first surface, and a second surface disposed opposite to the first surface; 
 a first conductive feature formed on the first surface; 
 a second conductive feature formed on the second surface; and 
 a via filled with conductive material that extends from the second conductive feature through the dielectric to the first conductive feature; 
 wherein the second surface has a surface roughness between 40 nanometers and 75 nanometers, shaped at least in part by a surface of a previously-applied laminate. 
   
     
     
         18 . The system of  claim 17 , further comprising a touch screen display coupled with the die and the package substrate. 
     
     
         19 . The system of  claim 17 , wherein the system is a mobile electronic device.