Structural and Dielectric Properties of Laser Crystallized BST Thin Films for Microwave Device Applications

Ba
0.5
Sr
0.5
TiO
3
(BST) thin films are deposited by Pulsed Laser Deposition (PLD) at 300
^o
C on platinized sapphire and laser annealed for crystallization at the same temperature which is much lower than the normal crystallization temperature for these thin films which is 700
^o
C. The laser annealed films are XRD crystalline and the dielectric properties in the low frequencies and microwave frequencies are studied. The microwave dielectric properties are measured by fabricating a circular patch capacitor structure and a dielectric tunability of 30% is obtained for these low-temperature crystallized films.