Properties of Ba(Mg1/3Ta2/3)O3 thin films prepared by pulsed-laser deposition

The dielectric properties of Ba(Mg1/3Ta2/3)O-3 (BMT) microwave thin films synthesized by an in situ pulsed-laser deposition (PLD) process were compared with those prepared by a two-step PLD process. The onset of crystallization for the BMT films is approximately 400degreesC, when in situ deposited, and is approximately 550degreesC, when two-step processed. Dielectric measurements indicate that complete crystallization for BMT films can be achieved only by processing the films at a sufficiently high temperature, which is 600degreesC for an in situ PLD process and is 800degreesC for a two-step PLD process. The microwave dielectric properties of BMT films, which were directly measured by an evanescent microwave probe (EMP) technique at 2.65 GHz measuring frequency, increase with substrate temperature, resulting in dielectric constant K = 33.3 and dissipation factor tan delta = 0.0158.