The present invention provides a composition comprising: (a)
dielectric material; and (b) porogen comprising at least two fused aromatic rings wherein each of the fused aromatic rings has at least one
alkyl substituent thereon and a bond exists between at least two of the
alkyl substituents on adjacent aromatic rings. Preferably, the
dielectric material is a composition comprising (a) thermosetting component comprising (1) optionally
monomer of Formula I as set forth below and (2) at least one
oligomer or
polymer of Formula II as set forth below where Q, G, h, I, I, and w are as set forth below and (b) porogen. Preferably, the porogen is selected from the group consisting of unfunctionalized polyacenaphthylene homopolymer, functionalized polyacenaphthylene homopolymer, polyacenaphthylene
copolymer, polynorbornene,
polycaprolactone, poly(2-vinylnaphthalene), vinyl
anthracene,
polystyrene,
polystyrene derivatives, polysiloxane,
polyester, polyether, polyacrylate, aliphatic
polycarbonate,
polysulfone, polylactide, and blends thereof. The present compositions are particularly useful as
dielectric substrate material in microchips, multichip modules, laminated circuit boards, and printed wiring boards.