TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The olefin based elastomer: is an ethylene propylene diene terpolymer; and is a copolymer comprised of at least 50 wt.% of monomer units comprising ethylene or propylene monomer units copolymerized with at least one different 2-20C alpha -olefin monomer units, where the olefin based elastomer has a melt index of less than 25 g/10 minutes measured according to ASTM D1238. In the sheet: the metal wires are disposed directly on the first surface of the homogeneous polymer substrate, are at least partially embedded in the homogeneous polymer substrate, and are at least partially exposed at the first surface of the homogeneous polymer substrate; and the metal wires are buried in the homogeneous polymer substrate, where vias connect the buried metal wires in the homogeneous polymer substrate to the first surface of the polymer substrate. In the sheet: a polymeric conductive adhesive is disposed in the vias that connect to the first surface of the homogeneous polymer substrate; the second surface of the homogeneous polymer substrate is adhered directly to a fluoropolymer film; the second surface of the homogeneous polymer substrate is an exposed surface; and the homogeneous polymer substrate has a thickness of 0.4-1.5 mm. The homogeneous polymer substrate comprises 25-90 wt.% olefin-based elastomer, 10-70 wt.% of inorganic particulates, and 5-50 wt.% of adhesive comprising thermoplastic polymer adhesives or rosin based tackifiers, based on the weight of the polymer substrate. The inorganic particulates have an average particle diameter between and including any two of 0.1, 0.2, 15, 45 or 100 mu . The inorganic particulates comprises calcium carbonate, titanium dioxide, kaolin and clays, alumina trihydrate, talc, silica, silicates, antimony oxide, magnesium hydroxide, barium sulfate, mica, vermiculite, alumina, titania, wollastonite and/or boron nitride. The conductive metal wires comprise a metal which is copper, nickel, tin, silver and/or aluminum. The adhesive of the homogeneous polymer substrate is a non-aromatic thermoplastic copolymer comprised of ethylene units copolymerized with at least one of the monomer units comprising 3-20C alpha -olefins, 1-4C alkyl methacrylates, 1-4C alkyl acrylates, methacrylic acid, acrylic acid, maleic anhydride or glycidyl methacrylate, where the adhesive copolymer or thermoplastic copolymer adhesive comprises at least 50 wt.% ethylene derived units. In the back-contact solar module: the metal wires are buried in the homogeneous polymer substrate; the first surface of homogeneous polymer substrate directly adheres to the rear surface of the solar cells; vias connect the buried metal wires in the homogeneous polymer substrate to the first surface of the homogeneous polymer substrate; a polymeric conductive adhesive is disposed in the vias that connect to the first surface of the homogeneous polymer substrate; and the metal wires are physically and electrically connected to the positive and negative polarity electrical contacts on the rear surface of the solar cells by polymeric conductive adhesive. In the back-contact solar module the electrically conductive metal wires are disposed on the first surface of the homogeneous polymer substrate. The back-contact solar module further comprises a polymeric interlayer dielectric layer having opposite first and second sides disposed between the electrically conductive metal wires on the back-sheet and the rear surface of the solar cells of the solar cell array. The inter- layer dielectric layer has openings arranged in many columns, where the interlayer dielectric layer is adhered on its first side to the rear surface of the solar cells of the solar cell array and on its second side to the first side of the polymer substrate over the conductive metal wires. The columns of openings in the interlayer dielectric layer are arranged over the conductive wires adhered to the first side of the polymer substrate so that the openings in each column of openings are aligned with and over one of the electrically conductive wires. The openings in the interlayer dielectric layer are aligned with the positive and negative polarity electrical contacts on the rear surfaces solar cells of the solar cell array, where the positive and negative polarity electrical contacts on the rear surfaces of the solar cells are electrically connected to the conductive wires through the openings in the interlayer dielectric layer.