Electrostatic methods and apparatus for mounting and demounting particles from a surface having an array of tacky and non-tacky areas

Abstract

Methods and associated apparatus are disclosed for use in mounting particles on and de-mounting particles from a substrate having an array of tacky and non-tacky areas. The particles can be either electrically conducting or electrically non-conducting. Selection of electrically conducting particles is preferred. The substrate having an array of tacky and non-tacky areas can either be electrically nonconducting (e.g., a dielectric substrate) or electrically-conducting. The methods involve use of first and second electrode plates with the substrate therebetween, the plates having applied thereto a direct current potential, which potential in preferred embodiments is reversed in polarity for a number N of cycles. Methods and articles are disclosed using an electrically conductive surface adjacent the tacky and non-tacky areas to minimize static buildup on the particles and tacky and non-tacky areas.

1 - 30 . (canceled)  
   
   
       31 . An article for use in mounting free-flowing particles in an array, comprising: 
 (a) a substrate having thereon an array of tacky and non-tacky areas; and    (b) a conducting layer adjacent the tacky and non-tacky areas; wherein each of the tacky areas has a size and bounding strength suitable for adhesion of one particle thereto.    
   
   
       32 . The article of  claim 31  wherein the substrate (a) and the conducting layer (b) are present in one layer.  
   
   
       33 . The article of  claim 31  wherein the conducting layer (b) comprises a material selected from the group consisting of a metal, a metal oxide, and an electrically-conductive polymer.  
   
   
       34 . The article of  claim 33  wherein the metal or the metal oxide is selected from the group consisting of aluminum, copper, and indium tin oxide.  
   
   
       35 . An article for use in mounting an array of particles to contact pads of an electronic device, comprising: 
 (a) a surface having thereon an array of tacky and non-tacky areas and wherein each of the tacky areas has a size and bounding strength suitable for adhesion of one particle thereto, the tacky areas arranged on the contact pads; and    (b) a conducting layer adjacent the tacky and non-tacky areas; and    (c) an electrically-conductive particle is attached to each tacky area and the non-tacky area is essentially free of particles.    
   
   
       36 . The article of  claim 35  wherein the electrically-conductive particle comprises a material selected from the group consisting of a metal, a metal oxide, an electrically-conductive polymer, solder and solder with flux.  
   
   
       37 - 42 . (canceled)