37 Preparation and Characterization of Dielectric Thin Films by RF Magnetron-Sputtering with (Ba 0.3 Sr 0.7 )(Zn 1/3 Nb 2/3 )O 3 Ceramic Target Feng Shi College of Physics & Electronics, Shandong Normal University, P.R. China 1. Introduction Barium-strontium-zinc niobate (BSZN) [(Ba x Sr 1-x )(Zn 1/3 Nb 2/3 )O 3 , where x is the mole fraction and 0 ≤ x ≤ 1] is one of the ( ) 13 23 3 AB B O ′ ′′ type microwave dielectric ceramics which have many advantage properties at very high microwave frequency, such as extremely low dielectric loss and near zero temperature coefficient of resonance frequency with low cost (Xu et al., 2006; Yu et al., 2006; Ianculescu et al., 2007; Huang et al., 2006; Varma et al., 2006). Due to these properties, BSZN has several potential applications in the fields of satellite communication and radar and mobile communication systems. As promising materials used in microelectronic and microwave integration circuit, microwave dielectric ceramic thin films will attract great attention in the near future (Huang et al., 2006). Radio frequency (RF) magnetron sputtering is a dominant technique to grow thin films because a large quantity of thin films can be prepared at relatively high purity and low cost. The growth of thin films using (Ba x Sr 1-x )(Zn 1/3 Nb 2/3 )O 3 microwave dielectric ceramic as target materials has not been reported all over the world except my group (Cui et al., 2010; Shi et al., 2010) and there is very little information for direct reference. In this article, the thin films were initially prepared by radio frequency magnetron sputtering system using sintered (Ba x Sr 1-x )(Zn 1/3 Nb 2/3 )O 3 microwave dielectric ceramic as target. Then the deposited samples were annealed in oxygen ambience at different powers of 150 W, 200 W, and 250 W, different pressures of 0.1 Pa, 0.25 Pa, 0.5 Pa, 0.7 Pa, and 1.0 Pa, different annealing temperatures of 850 ℃, 1000 ℃, and 1150 ℃ and different annealing times of 15 min, 30 min, 45 min, and 60 min. The microstructure, components and surface morphology properties are investigated in detail, and the effect of experimental conditions on the growth of the thin films is studied in particular. 2. Experimental procedure Ceramic thin films were deposited on SiO 2 (110) substrates by adopting sintered (Ba x Sr 1-x )(Zn 1/3 Nb 2/3 )O 3 microwave dielectric ceramics as sputtering target with a size of 62- × 3 mm in a JGP-450 radio frequency magnetron sputtering system. The SiO 2 (110) substrate was ultrasonically cleaned in an acetone and followed by rinsing in de-ionized www.intechopen.com