Dielectric composite material

Abstract

A dielectric composite material containing a toughened benzocyclobutene resin and at least about 50% by weight of an inorganic filler. Also electronic packages having at least one conductive layer and at least one layer of the dielectric composite material. The dielectric composite material can have a dielectric constant less than about 3.5, and a dielectric loss of less than about 0.004.

1 . A substrate structure comprising a conductive layer coated with at least one layer of dielectric composite material, said dielectric composite material having a dielectric constant less than about 3.5, a dielectric loss of less than about 0.004, including a toughened benzocyclobutene resin, and from about 50% to about 75% by weight of at least one inorganic particulate filler, the resin and the filler being compatibilized by means of a silane coupling agent.  
   
   
       2 . A substrate structure according to  claim 1  wherein said conductive layer is a copper layer.  
   
   
       3 . A substrate structure according to  claim 1  wherein said conductive layer is formed from a laminated low profile copper, or plated copper, or sputtered aluminum, having a thickness of less than about 15 μm.  
   
   
       4 . A substrate structure according to  claim 1  wherein said at least one inorganic particulate filler is a particulate silica having an average particle size less than or equal to ten percent of the thickness of a layer of the dielectric composite material.  
   
   
       5 . A substrate structure according to  claim 1  wherein said silane coupling agent is selected from the group consisting of vinyltriethoxysilane, vinyltriacetoxysilane, 7-octenyltrimethoxysilane, and mixtures thereof.  
   
   
       6 . A substrate structure according to  claim 1  wherein said structure further includes a primer on said copper surface, said primer being selected from the group consisting of vinyltriacetoxysilane, aminosilane, and aminopropylsilane.