Low Temperature Microwave Characterisation of GreenTapes using Split Post Dielectric Resonator M. V. Jacob 1 , S. Thomas 2 , M. Sebastian 2 , J. Mazierska 3, 1 , J. Honkama 4 and H. Jantunen 4 , 1 Electronic Material Research Laboratory, School of Engineering, James Cook University, Townsville QLD 4811 Australia 2 National Institute for Interdisciplinary Science and Technology Trivandrum 695019, India 3 Massey University, School of Engineering and Advanced Technology, New Zealand 4 INFOTECH, University of Oulu, Finland 1 mohan.jacob@jcu.edu.au Abstract – Investigation into the fabrication of dielectric materials suitable for low temperature co-fired ceramic (LTCC) applications and their characterisation at high frequencies is a prominent research area. There has been number of papers featuring the analyses of performance of LTCC materials at microwave frequencies published. However there are no reports presenting microwave properties of source materials, before firing takes place, (Greentape). High frequency dielectric properties of Greentape material in the temperature range from 10K to 290 K using a split post dielectric resonator has been presented in this paper. We investigated two Greentape materials of differing thicknesses (0.08 mm and 0.13 mm) at a frequency of 10 GHz. INTRODUCTION Low Temperature Co-fired ceramic (LTCC) is one of the most powerful Multi Chip Module (MCM) technologies for wireless communication circuits. The main advantage of the LTCC is the fabrication of three-dimensional circuits, in which resistors, inductors, capacitors and low loss interconnects are “buried” within a ceramic block, resulting in high integration, hermetical sealing and electromagnetic shielding. Due to the advantages of this technology the LTCC-based components are used in commercial microwave applications such as WLAN transceivers, cellular telephony and portable wireless devices [1-6]. Further advancement can be achieved by identifying new materials suitable for the LTCC technology and improving the existing ones [4-6]. Since the materials are likely to find applications at higher frequencies and varying ambient environment, it is important to investigate their microwave properties at differing temperatures. For fabrication of Low Temperature Co-fired Ceramics, thin layers of materials referred to as ‘Greentape’ are used despite the colour before firing being usually white, not green. The thickness of LTCC materials is controlled by adding more layers of Greentape, and this process could change the microwave losses of the resulting LTCC structure. This paper aims to precisely measure the microwave properties of a greentape material of low ε r of two differing thickness as a function of temperature. EXPERIMENTS Powder preparation The 0.83 ZnAl 2 O 4 -0.17 TiO 2 (ZAT) ceramics were prepared by the conventional solid state ceramic route [7]. High purity ZnO [Aldrich Chemical Company, 99.9%] and Al 2 O 3 [Alcoa A16SG] were used as starting materials for the synthesis of ZnAl 2 O 4 . The chemicals were stoichiometrically weighed and were ball milled in polyethylene bottle using Zr balls in 978-1-4244-2642-3/08/$25.00 ©2008 IEEE