In accordance with the invention, a low dielectric constant insulation material is provided which comprises {HEAD ~ a porous insulation layer}, preferably sandwiched between {TAIL ~ non porous upper and lower insulation layers} 
In accordance with the invention , a low dielectric constant insulation material is provided which comprises { HEAD ~ a porous insulation layer } , preferably sandwiched between { TAIL ~ non porous upper and lower insulation layers }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL