Wiring substrate

Abstract

A substrate is provided on which wires can be formed satisfactorily using a dispersion liquid of metal microparticles without causing disconnection or short circuit. The wiring substrate comprises a substrate, an organic membrane formed on the substrate, and a metal wire formed on the organic membrane. An arithmetic mean deviation Ra of the profile of the surface of the organic membrane where the metal wire is formed is not less than 60 nm and not more than 5×10 −2 D, where D is the width of the metal wire. The contact angle with respect to water on the surface of the organic membrane where the metal wire is formed is not less than 110°.

1 . A wiring substrate comprising a substrate, an organic membrane formed on said substrate, and a metal wire formed on said organic membrane, wherein Ra is not less than 60 nm and not more than 5×10 −2  D, where D is the width of said metal wire, and Ra is an arithmetic mean deviation of the profile of the surface of said organic membrane where said metal wire is formed, and wherein the contact angle with respect to water on the surface of said organic membrane where said metal wire is formed is not less than 110°.  
     
     
         2 . The wiring substrate according to  claim 1 , wherein said organic membrane comprises a mixture of a resin and silicon-oxide microparticles.  
     
     
         3 . The wiring substrate according to  claim 1 , wherein said organic membrane comprises a compound including a perfluoropolyether chain or a perfluoroalkyl chain.  
     
     
         4 . The wiring substrate according to  claim 1 , wherein said organic membrane comprises a mixture of a resin, silicon-oxide microparticles, and a fluorine-containing compound having the following structure:  
         Rf(R)z  
       where Rf has the following structure:  
         [F{CF(CF 3 )—CF 2 O} m —CF(CF 3 )]—CONH— {F(CF 2 CF 2 CF 2 O) m′ —CF 2 CF 2 }—CONH— or  —HNOC{CF 2 O—(CF 2 CF 2 O) n —(CF 2 O) n′ —CF 2 }—CONH— 
       where m, m′, n, and n′ are natural numbers; and 
 where R has the following structure:  
                     
 where z is 1 or 2.  
 
     
     
         5 . The wiring substrate according to  claim 1 , wherein said organic membrane comprises a fluorine-containing compound chemically bonded to the surface thereof, said fluorine-containing compound including an alkoxysilane structure at the terminal thereof.  
     
     
         6 . The wiring substrate according to  claim 5 , wherein said organic membrane comprises a fluorine-containing compound chemically bonded to the surface thereof, said fluorine-containing compound including an alkoxysilane structure having the following structure:  
         [F{CF(CF 3 )—CF 2 O} n —CF(CF 3 )]—X—Si(OR) 3    {F(CF 2 CF 2 CF 2 O) n }—X—Si(OR) 3    {H(CF 2 ) n }—Y—Si(OR) 3    {F(CF 2 ) n }—Y—Si(OR) 3    
       where X is a binding site of a perfluoropolyether chain and an alkoxysilane residue, Y is a binding site of a perfluoroalkyl chain and an alkoxysilane residue, and R is an alkyl group.  
     
     
         7 . A wiring substrate comprising a substrate, and a metal wire formed on said substrate, wherein Ra is not less than 60 nm and not more than 5×10 −2  D, where Ra is an arithmetic mean deviation of the profile of said substrate and D is the width of said metal wire, and wherein the contact angle with respect to water on the surface of said substrate where said metal wire is formed is not less than 110°.  
     
     
         8 . The wiring substrate according to  claim 7 , wherein said substrate comprises polytetrafluoroethylene.  
     
     
         9 . The wiring substrate according to  claim 7 , wherein said substrate comprises a fluorine-containing compound chemically bonded to the surface thereof, said fluorine-containing compound having an alkoxysilane structure at the terminal thereof.  
     
     
         10 . The wiring substrate according to  claim 5 , wherein said substrate comprises a fluorine-containing compound chemically bonded to the surface thereof, said fluorine-containing compound including an alkoxysilane structure having the following structure:  
         [F{CF(CF 3 )—CF 2 O} n —CF(CF 3 )]—X—Si(OR) 3    {F(CF 2 CF 2 CF 2 O) n }—X—Si(OR) 3    {H(CF 2 ) n }—Y—Si(OR) 3    {F(CF 2 ) n }—Y—Si(OR) 3    
       where X is a binding site of a perfluoropolyether chain and an alkoxysilane residue, Y is a binding site of a perfluoroalkyl chain and an alkoxysilane residue, and R is an alkyl group.  
     
     
         11 . A method of manufacturing a wiring substrate comprising a substrate,. an organic membrane formed on said substrate, and a metal wire formed on said organic membrane, said method comprising the steps of: 
 forming an organic membrane on a substrate;    providing said organic membrane with an arithmetic mean deviation of profile of not less than 60 nm and not more than 5×10 −2  D, where D is the width of said metal wire, and with a contact angle with respect to water of not less than 110°;    applying a dispersion liquid containing metal microparticles to said organic membrane; and    heating the dispersion liquid that has been applied.    
     
     
         12 . A method of manufacturing a wiring substrate comprising a substrate, and a metal wire formed on said substrate, said method comprising the steps of: 
 providing said substrate with an arithmetic mean deviation of profile of not less than 60 nm and not more than 5×10 −2  D, where D is the width of said metal wire, and with a contact angle with respect to water of not less than 110°;    applying a dispersion liquid containing metal microparticles to said substrate; and    heating the dispersion liquid that has been applied.    
     
     
         13 . The wiring substrate according to  claim 1 , wherein said organic membrane comprises a mixture of a polyimide resin and a compound including a perfluoropolyether chain or a perfluoroalkyl chain.