ULTCC Glass Composites Based on Rutile and Anatase with Cofiring at 400 °C for High Frequency Applications
| Autor: | Timo Vahera, Prasadh Ramachandran, Jobin Varghese, Maciej Sobocinski, Heli Jantunen |
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| Rok vydání: | 2018 |
| Předmět: |
Anatase
Materials science General Chemical Engineering microwave substrates Relative permittivity 02 engineering and technology Dielectric Tape casting 010402 general chemistry cofiring 01 natural sciences 7. Clean energy tape casting Environmental Chemistry Ceramic ceramic−glass Composite material Ceramic−glass Microwave substrates Renewable Energy Sustainability and the Environment General Chemistry Atmospheric temperature range ULTCC 021001 nanoscience & nanotechnology 0104 chemical sciences 13. Climate action Rutile visual_art Cofiring visual_art.visual_art_medium Dielectric loss 0210 nano-technology Research Article |
| Zdroj: | ACS Sustainable Chemistry & Engineering |
| ISSN: | 2168-0485 |
| Popis: | The article presents the very first materials to the ultralow temperature cofired ceramic (ULTCC) technology with the sintering temperature of 400 °C. The dielectric composites are based on a rutile and anatase with commercial GO17 sealing glass. In addition to the bulk samples, the tape casting procedure is also introduced to show its feasibility to cofiring with commercial Ag electrodes at 400 °C. The structural, microstructural, thermal, and microwave dielectric properties in the green and sintered samples were investigated. The optimum amount of glass to fabricate substrates was found to be 30 vol %. The ULTCC substrates with the anatase TiO2A-30GO17 and rutile TiO2R-30GO17 that were sintered at 400 °C showed a relative permittivity of 9.9 and 15 and a dielectric loss of 0.006 and 0.003, respectively, at the measurement frequency of 9.9 GHz. The temperature dependences of the relative permittivity were +70 and −400 ppm/°C, respectively. Moreover, the coefficients of the thermal expansion of the substrates were 7.4 and 8.3 ppm/°C in the measured temperature range of 50–300 °C. A preliminary test to study the feasibility of the anatase TiO2A-30GO17 for a dual band antenna was performed due its relatively stable temperature behavior. The ULTCC research highlights the future low cost fabrication of devices with less CO2 emission with existing high temperature technology. |
| Databáze: | OpenAIRE |
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