Method of forming a layer on a substrate to facilitate fabrication of metrology standards

Abstract

The present invention is directed to a method of forming a layer on a solidified portion of a substrate that facilitates fabrication of metrology standards. The method features defining a planarity of the layer, which is formed by creating a flowable region on the solidified portion of the substrate, as a function of the volume of the flowable material in the region. Recognizing that the topology of a substrate upon which the layer is formed is not planar, on the nano-scale, the present invention is directed to fabricating high resolution features on the substrate and transferring the features into a solidified region of the substrate. Specifically, by minimization of the layer thickness while maximizing the planarity of the interface of the layer with the solidified portion of the substrate, it was found that very small features may be precisely and repeatably formed in the substrate.

What is claimed is:  
     
         1 . A method of forming a layer on a substrate to facilitate fabrication of metrology standards, said method comprising: 
 creating a flowable region on said substrate, defining a fluid state, with said flowable region having a volume associated therewith; and    defining a layer over an area of said region having opposed sides, one of which faces said substrate, defining an interface, with said opposed side facing away from said substrate, said layer having a thickness measured between said opposed sides, with said volume being selected to maximize a planarity of said interface over said area.    
     
     
         2 . The method as recited in  claim 1  wherein said thickness is selected to minimize visco-elastic properties of in said flowable region liquid in said layer.  
     
     
         3 . The method as recited in  claim 2  wherein said thickness is no less than 10 nano-meters.  
     
     
         4 . The method as recited in  claim 1  further including solidifying said region, defining a solidified state, with said flowable region consisting of material to minimize dimensional changes of said material when transitioning between said liquid and solidified states.  
     
     
         5 . The method as recited in  claim 1  wherein creating further includes depositing, upon said substrate, a bead of polymerizable material and defining further includes contacting said liquid bead with a mold having a relief structure on a surface thereof to create a recess in said side facing away from said substrate and subjecting said layer to conditions to polymerize said polymerizable material, forming a polymerized layer.  
     
     
         6 . The method as recited in  claim 5  wherein contacting further includes contacting said liquid with said mold having a plurality of relief structures formed from multiple recessions and protrusions formed into said surface to create a plurality of said recess on said side facing away from said substrate, with said multiple recessions and protrusions arranged to provide said surface with a substantially uniform fill factor.  
     
     
         7 . The method as recited in  claim 5  wherein contacting further includes contacting said liquid with said mold having a plurality of periodic relief structures formed from multiple recessions and protrusions formed into said surface.  
     
     
         8 . The method as recited in  claim 5  wherein contacting further includes contacting said liquid with said mold with minimal force to achieve spreading primarily through capillary action of said liquid with said surface.  
     
     
         9 . The method as recited in  claim 5  wherein said substrate has a crystalline structure and said recess has a nadir and further including etching said layer and said substrate to form a via in said region of said substrate in superimposition with said nadir, with said via having walls that extend transversely to said nadir and parallel to a  110  plane of said crystalline structure.  
     
     
         10 . A method of forming a layer on a substrate to facilitate fabrication of metrology standards, said method comprising: 
 depositing a bead of liquid upon said substrate, with said bead having a volume associated therewith; and    spreading said bead over an area of said substrate to define a layer having first and second opposed sides, which is in a liquid state, with said first side facing said substrate and having a planarity associated therewith, with said second side facing away from said substrate, said layer having a minimum thickness measured between said first and second sides, with said planarity, for said minimum thickness, being defined by said volume, and said minimum thickness selected to reduce visco-elastic properties of said liquid in said layer.    
     
     
         11 . The method as recited in  claim 10  including solidifying said layer, defining a solidified state, with said layer consisting of material to minimize dimensional changes of said material when transitioning between said liquid and solidified states.  
     
     
         12 . The method as recited in  claim 11  wherein said bead of viscous liquid is a polymerizable material and spreading further includes contacting said liquid bead with a mold having a plurality of relief structures defined by multiple recessions and protrusions, formed into a surface of said mold, to create a plurality of recesses on said second side, with said multiple recessions and protrusions arranged to provide said surface with a substantially uniform fill factor, and subjecting said layer to conditions to polymerize said polymerizable material, forming a polymerized layer.  
     
     
         13 . The method as recited in  claim 12  further including arranging said plurality of relief structures on said mold to be periodic.  
     
     
         14 . The method as recited in  claim 13  wherein contacting further includes contacting said liquid with said mold with minimal force to achieve spreading primarily through capillary action of said liquid with said surface.  
     
     
         15 . The method as recited in  claim 14  wherein said substrate has a crystalline structure and said recess has a nadir and further including etching said layer and said substrate to form a via in a region of said substrate in superimposition with said nadir, with said via having walls that extend transversely to said nadir and parallel to a  110  plane of said crystalline structure.  
     
     
         16 . A method for forming a layer on a substrate to facilitate fabrication of metrology standards, said method comprising: 
 depositing a bead of polymerizable viscous liquid upon said substrate, with said bead having a volume associated therewith;    spreading said bead over an area of said substrate by contacting said bead with a mold having a plurality of relief structures defined by multiple recessions and protrusions, formed into a surface of said mold, to define a layer having first and second opposed sides, with said first side facing said substrate and having a planarity associated therewith and said second side facing away from said substrate and having a plurality of recesses therein, each of which has a nadir, said layer having a thickness measured between said first side and a plane coplanar with each of the nadirs associated with said plurality of recesses, with said planarity being defined by said volume; and    subjecting said layer to conditions to polymerize said polymerizable material, forming a polymerized layer.    
     
     
         17 . The method as recited in  claim 16  wherein said thickness is selected to minimize visco-elastic properties of said liquid in said layer.  
     
     
         18 . The method as recited in  claim 16  wherein said multiple recessions and protrusions are arranged to provide said surface with a substantially uniform fill factor and further including placing silicon nano-balls into said viscous liquid.  
     
     
         19 . The method as recited in  claim 16  wherein contacting further includes contacting said bead with said mold with a requisite force to achieve spreading primarily through capillary action of said liquid with said surface.  
     
     
         20 . The method as recited in  claim 16  wherein said substrate has a crystalline structure and further including etching said layer and said substrate to form a via in regions of said substrate in superimposition with the nadir of each of said plurality of recesses, with said via having walls that extend transversely to said nadir and parallel to a 110 plane of said crystalline structure.