International ournal of Applied Ceramic Technolog-Sebastian and Jantunen Vol.7,No.4,2010 8 GHz. The Taclampus of Taconic has a loss tangent of 0.0004 with a low relative permittivity of 2. 1 at 10 GHz. Frequency The low E, facilitates in faster signal transmission, whereas a higher value of Er aids miniaturization of the devices. Thermal Conductivity Dielectrie constant Epoxy-silica composites have been used widely as because of their excal material for the last 35 years the electronic packagi ellen mechanical and electrical properties, low cost, and ease of processing. Silica has a low thermal conductivity of 1.5 W/mK. In order rmal COl Temperature(c) Bollampally used thermally conducting fillers such Fig. 8. Variation of relative permittivity and frequency of patch as alumina and aluminum nitride Figure 9 shows the antenna comprised of a mica/Sr/PPS (38/8/54/96)composite variation of thermal conductivity as a function of with temperature measured at 2 GHe(after Walpata et al o) volume loading of alumina, silica, and silica-coated alu- minum nitride. Addition of 50 vol% silica-coated alu- minum nitride increased the thermal conductivity 10 Table I. Dielectric Properties of Polymer-Ceramic Composites Polymer Filler Er Tan s Ref n2Si2O7 4.81 0.0055 8Ghz Thomas et al40 Ca(ILil3Nby/3)o.8Tio. 2JO3 0.4 7 8GHz George and Sebastian Li2MgSiO A 4 0.0032 8 GHz George 4 0.004 8 ghz Subodh et aL58 HDPE Sr2Ce2TisO1 0.4 11.0 8GHz Subodh et al. 63 Polystyrene Li2△ MgSio4 0.4 3.84 12 8GHz George et al. Polyester Sm,,o 0.4 4.34 0.0101 8 GHz Thomas et al. 40 P Sr2Ce2TisO15 13.6 8GHz Subodh et al 641 Polystyrene Ca(LilNbz/3).sTio.21O3 0.4 8 GHz George and Sebastian PTFE CeO2 7 GHz Anjana et al. PTFE 60wt% 8 GHz Chen and colleagu PTFE ZnAl2OA-TiOz 7 GHz Thomas et ai PTFE SrTiO3 0.63 13.1 10 GHz Rajesh PTFE TiO 10.2 8 GHz Rajesh et al.8 PTFE 2MgO-2Al2O3-5SiO2 60 wt% 3.1 10GHz Murali et al PTFE 2MgO-2Al2O3-5SiO2 10 2.17 10GHz Murali et aL.6 PTFE Bi2O3-ZnO-Nb20 0.6 12.5 PTFE A 0.66 4.3 800 MHz Xiang et a,35 PTFE 0.56 3.35 10GHz Murali et al35 PTFE 11.8 10 GHz Rajesh et al. PTFE aNdSmTi,O1 67wt% 8.0 PTFE LSCO 0.3 25,000 I MHz Deepa et al. PTFE Sr,CenT 0.4 772 7GHz Subodh et al. 74 POE SrTiO3 0.4 11.0 0.9 GHz Xiang et al. POE SrTiO -NiZn ferrite 5.4 0.0018 100Hz Yang et al75 PEEK TiO2 25 499 8GHz Raiesh et al Poly(methymetho Bao. Sro 4TiO3 0.416 1212 0.026 10 KHz Xiang et al. Metallocene cyclic Soda lime borosilicate 0.36 192 0.0009 I MHz yang et al238 GHz. The Taclampus of Taconic has a loss tangent of 0.0004 with a low relative permittivity of 2.1 at 10 GHz. The low er facilitates in faster signal transmission, whereas a higher value of er aids miniaturization of the devices. Thermal Conductivity Epoxy–silica composites have been used widely as the electronic packaging material for the last 35 years because of their excellent mechanical and electrical properties, low cost, and ease of processing.97 Silica has a low thermal conductivity of 1.5 W/mK. In order to increase the thermal conductivity, Wong and Bollampally98 used thermally conducting fillers such as alumina and aluminum nitride. Figure 9 shows the variation of thermal conductivity as a function of volume loading of alumina, silica, and silica-coated alu￾minum nitride. Addition of 50 vol% silica-coated alu￾minum nitride increased the thermal conductivity 10 Fig. 8. Variation of relative permittivity and frequency of patch antenna comprised of a mica/SrTiO3/PPS (38/8/54 vol%) composite with temperature measured at 2 GHz (after Walpata et al.60). Table I. Dielectric Properties of Polymer–Ceramic Composites Polymer Filler Vf er Tan d Fo Ref Polyethylene Sm2Si2O7 0.4 4.81 0.0055 8 GHz Thomas et al. 40 Polyethylene Ca([Li1/3Nb2/3)0.8Ti0.2]O3 0.4 7.72 0.004 8 GHz George and Sebastian61 Polyethylene Li2MgSiO4 0.4 3.54 0.0032 8 GHz George et al. 62 Polyethylene Sr9Ce2Ti12O36 0.4 12.1 0.004 8 GHz Subodh et al. 58 HDPE Sr2Ce2Ti5O15 0.4 11.0 0.006 8 GHz Subodh et al. 63 Polystyrene Li2MgSiO4 0.4 3.84 0.012 8 GHz George et al. 62 Polyestyrene Sm2Si2O7 0.4 4.34 0.0101 8 GHz Thomas et al. 40 Polystyrene Sr2Ce2Ti5O15 0.5 13.6 0.0004 8 GHz Subodh et al. 64 Polystyrene Ca([Li1/3Nb2/3)0.8Ti0.2]O3 0.4 7.4 0.003 8 GHz George and Sebastian61 PTFE CeO2 0.6 5.0 0.0064 7 GHz Anjana et al. 65 PTFE SiO2 60 wt% 2.9 0.0024 8 GHz Chen and colleagues34,35 PTFE ZnAl2O4–TiO2 0.6 4.8 0.008 7 GHz Thomas et al. 66 PTFE SrTiO3 0.63 13.1 0.0055 10 GHz Rajesh et al. 67 PTFE TiO2 0.67 10.2 0.022 8 GHz Rajesh et al. 68 PTFE 2MgO–2Al2O3–5SiO2 60 wt% 3.17 0.0034 10 GHz Murali et al. 69 PTFE 2MgO–2Al2O3–5SiO2 10 wt% 2.17 0.0007 10 GHz Murali et al. 69 PTFE Bi2O3–ZnO–Nb2O5 0.6 12.5 0.001 800 MHz Xiang et al. 70 PTFE Al2O3 0.66 4.3 0.0021 10 GHz Murali et al. 35 PTFE MgO 0.56 3.35 0.015 10 GHz Murali et al. 35 PTFE CaTiO3 11.8 0.0036 10 GHz Rajesh et al. 71 PTFE BaNdSmTi4O12 67 wt% 8.04 0.009 Jacob et al. 72 PTFE LSCO 0.3 25,000 1 MHz Deepa et al. 73 PTFE Sr2Ce2Ti5O16 0.4 7.72 0.08 7 GHz Subodh et al. 74 POE SrTiO3 0.4 11.0 0.010 0.9 GHz Xiang et al. 27 POE SrTiO3–NiZn ferrite 5.4 0.0018 100 Hz Yang et al. 75 PEEK TiO2 25 wt% 4.99 0.0087 8 GHz Rajesh et al. 76 Poly(methymetho crylate) Ba0.6Sr0.4TiO3 0.416 1212 0.026 10 KHz Xiang et al. 22 Metallocene cyclic olefin coploymer Soda lime borosilicate 0.36 1.92 0.0009 1 MHz Yang et al. 23 422 International Journal of Applied Ceramic Technology—Sebastian and Jantunen Vol. 7, No. 4, 2010