Method and apparatus for forming a metallic feature on a substrate

Abstract

A method of forming a metallic feature on a substrate, comprising the steps of: providing a stamp having a raised region; depositing catalytic particles on a selected area of the stamp, including the raised region thereof; providing a substrate; applying the stamp to the substrate, such that the raised region of the stamp causes a corresponding indented region in the substrate and at least some of the catalytic particles are transferred to a selected area of the substrate; and plating the selected area of the substrate.

1 . A method of forming a metallic feature on a substrate, comprising the steps of: 
 providing a mould, an inner surface thereof having a raised region, depositing catalytic particles on a selected area of the inner surface of the mould, including the raised region thereof;    providing a substrate material;    moulding the substrate material within the mould, such that a resulting substrate has an indented region corresponding to the raised region of the inner surface of the mould and at least some of the catalytic particles are transferred to a selected area of the substrate;    and plating the selected area of the substrate.    
   
   
       2 . A method according to  claim 1 , wherein the step of depositing catalytic particles on the selected area of the inner surface of the mould comprises the step of immersing at least the selected area of the inner surface of the mould in a suspension comprising the catalytic particles.  
   
   
       3 . A method according to  claim 2 , wherein the step of immersing at least the selected area of the inner surface of the mould in a suspension comprising the catalytic particles comprises the step of immersing at least the selected area of the inner surface of the mould in an aqueous suspension comprising the catalytic particles.  
   
   
       4 . A method according to  claim 2 , further comprising the step of drying at least the selected area of the mould, after immersion thereof in the suspension.  
   
   
       5 . A method according to  claim 4 , wherein the step of drying at least the selected area of the mould comprises the step of blow drying at least the selected area of the mould with a gas.  
   
   
       6 . A method according to  claim 5 , wherein the step of blow drying the selected area with a gas comprises the step of blow drying the selected area with nitrogen, helium or air.  
   
   
       7 . A method according to  claim 4 , wherein the step of depositing catalytic particles on the selected area of the inner surface of the mould comprises the step of depositing polymer-stabilised catalytic particles on the selected area of the inner surface of the mould.  
   
   
       8 . A method according to  claim 7 , wherein the step of depositing polymer-stabilised catalytic particles on the selected area of the inner surface of the mould comprises the step of depositing catalytic particles stabilised by polyvinylpyrrolidone, poly-2-vinylpyridine or polyvinyl alcohol on the selected area of the inner surface of the mould.  
   
   
       9 . A method according to  claim 1 , wherein the step of depositing catalytic particles on the selected area of the inner surface of the mould comprises the step of depositing palladium-based catalytic particles on the inner surface of the mould.  
   
   
       10 . A method according to  claim 9 , wherein the step of depositing catalytic particles on the selected area of the inner surface of the mould comprises the step of depositing polymer-stabilised catalytic particles on the selected area of the inner surface of the mould.  
   
   
       11 . A method according to  claim 10 , wherein the step of depositing polymer-stabilised catalytic particles on the selected area of the inner surface of the mould comprises the step of depositing catalytic particles stabilised by polyvinylpyrrolidone, poly-2-vinylpyridine or polyvinyl alcohol on the selected area of the inner surface of the mould.  
   
   
       12 . A method according to  claim 1 , wherein the step of providing a substrate material comprises the step of providing a polymeric substrate material.  
   
   
       13 . A method according to  claim 12 , wherein the step of depositing catalytic particles on the selected area of the inner surface of the mould comprises the step of immersing at least the selected area of the inner surface of the mould in a suspension comprising the catalytic particles.  
   
   
       14 . A method according to  claim 13 , further comprising the step of drying at least the selected area of the mould, after immersion thereof in the suspension.  
   
   
       15 . A method according to  claim 12 , wherein the step of providing a polymeric substrate material comprises the step of providing a thermoset substrate material, and wherein the step of moulding the substrate material comprises the steps of: moulding the substrate material in an uncured or partially cured state; and curing the substrate material in the mould.  
   
   
       16 . A method according to  claim 12 , wherein the step of providing a polymeric substrate material comprises the step of providing a thermoplastic substrate material, and wherein the step of moulding the substrate material comprises the step of heating the substrate material to around or above the glass transition temperature thereof.  
   
   
       17 . A method according to  claim 12 , wherein the step of providing a polymeric substrate material comprises the step of providing a substrate formed from a polystyrene, a polyimide, an acrylic or an epoxy.  
   
   
       18 . A method according to  claim 17 , wherein the step of providing a polymeric substrate material comprises the step of providing a thermoset substrate material, and wherein the step of moulding the substrate material comprises the steps of: moulding the substrate material in an uncured or partially cured state; and curing the substrate material in the mould.  
   
   
       19 . A method according to  claim 17 , wherein the step of providing a polymeric substrate material comprises the step of providing a thermoplastic substrate material, and wherein the step of moulding the substrate material comprises the step of heating the substrate material to around or above the glass transition temperature thereof.  
   
   
       20 . A method according to  claim 1 , further comprising the step of removing some of the catalytic particles from the inner surface of the mould.  
   
   
       21 . A method according to  claim 20 , wherein the step of removing some of the catalytic particles from the inner surface of the mould comprises the steps of: applying an adhesive surface to the inner surface of the mould, and subsequently removing the adhesive surface from the inner surface of the mould.