Method of manufacturing a heat-transfer structure

Abstract

Method of manufacture, comprising forming a heat-transfer structure. Forming the heat-transfer structure includes forming a metallic planar substrate having a front surface and a back surface, the back surface being opposite the front surface. Forming the heat-transfer structure also includes forming an array of metallic raised features located directly on each of the front and back surfaces. Respective portions of the raised features are configured to be mechanically bend or buckle plastically deformable via a compressive force applied between a first substrate and a second substrate.

What is claimed is: 
     
         1 . A method of manufacture, comprising:
 forming a heat-transfer structure, including:
 forming a metallic planar substrate having a front surface and a back surface, the back surface being opposite the front surface; and 
 forming an array of metallic raised features located directly on each of the front and back surfaces, wherein respective portions of the raised features are configured to be mechanically bend or buckle plastically deformable via a compressive force applied between a first substrate and a second substrate, wherein one or more of the metallic raised features has a surface singularity therein prior to the mechanical bend or the buckle plastic deformation produced by the compressive force. 
   
     
     
         2 . The method of  claim 1 , wherein the one or more surface singularities are configured as caldera. 
     
     
         3 . The method of  claim 2 , wherein the metallic raised features are hollow. 
     
     
         4 . The method of  claim 2 , wherein there are at least two groups of the metallic raised features having two different heights. 
     
     
         5 . The method of  claim 2 , wherein
 the first substrate is a first integrated circuit having a first surface; and   the second substrate is a second integrated circuit having a second surface, each of the first and second surfaces being in direct physical contact with deformable ones of the raised features of one of the arrays.   
     
     
         6 . The method of  claim 2 , wherein the mechanically deformable metallic raised features provide physical connections between portions of a region of the first surface and the second surface, wherein the region of the first surface is non-planar. 
     
     
         7 . The method of  claim 2 , wherein the one or more surface singularities are in a vicinity of initial locations of the mechanical bend or the buckle plastic deformation. 
     
     
         8 . The method of  claim 1 , wherein the metallic raised features include a first cone-shaped portion and a second inverted cone-shaped portion and the surface singularity is located at a connection point between the first cone-shaped portion and the second inverted cone-shaped portion. 
     
     
         9 . The method of  claim 1 , wherein the metallic raised features include a plurality of merged cone-shaped features and the surface singularities are located at discontinuous merger points between adjacent one of the merged cone-shaped features. 
     
     
         10 . The method of  claim 9 , wherein the metallic raised features are cones. 
     
     
         11 . The method of  claim 1 , wherein the surface singularities are located at cross-cut points in the length of the metallic raised feature. 
     
     
         12 . The method of  claim 11 , wherein the metallic raised features are fins. 
     
     
         13 . The method of  claim 11 , wherein the metallic raised features are posts. 
     
     
         14 . The method of  claim 1 , wherein forming the metallic raised features includes metal plating the metallic raised features onto the front and back surfaces 
     
     
         15 . The method of  claim 1 , wherein forming the metallic raised features includes wire bonding the metallic raised features onto the front and back surfaces. 
     
     
         16 . The method of  claim 1 , wherein forming the metallic raised features includes cavity cast the metallic raised features onto the front and back surfaces. 
     
     
         17 . The method of  claim 1 , further including placing adhesive or thermal grease between the metallic deformable raised features. 
     
     
         18 . The method of  claim 1 , further including heat annealing the metallic raised features to reduce the modulus of the metallic raised features. 
     
     
         19 . A method of manufacture, comprising:
 forming a heat-transfer structure, including:
 forming a metallic planar substrate having a front surface and a back surface, the back surface being opposite the front surface; and 
 forming an array of metallic raised features located directly on each of the front and back surfaces, wherein respective portions of the raised features are configured to be mechanically bend or buckle plastically deformable via a compressive force applied between a first substrate and a second substrate, wherein the compressive force produces a compressive pressure in a range of 0.7 to 4.2 MPa. 
   
     
     
         20 . The method of  claim 19 , wherein each of the metallic raised features form a continuous phase of metal directly connecting the first surface and the second surface.