Target effects on electrical properties and laser induced voltages of La0.72Ca0.28MnO3 thin films prepared by pulsed laser deposition
(Faculty of Materials Science and Engineering, Kunming University of Science and Technology,
Kunming 650093, China)
Kunming 650093, China)
Abstract: La0.72Ca0.28MnO3 thin films were deposited on untilted and 15° tilted LaAlO3 (100) single crystalline substrates by pulsed laser deposition. The polycrystalline targets used in the deposition process were synthesized by sol-gel and coprecipitation methods, respectively. The structure, electrical transport properties and surface morphology of the targets and films were studied. It is found that, compared with coprecipitation method, the sol-gel target has more homogeneous components and larger density and grain size, thus the higher insulator-metal transition temperature and larger temperature coefficient of resistivity. The thin film prepared by sol-gel target has a uniform grain size and higher quality. The metal-insulator transition temperature is higher and the laser induced voltage signal is larger. Preparing the target by sol-gel method can largely improve the properties of corresponding thin films in pulsed laser deposition process.
Key words: La0.72Ca0.28MnO3; target; thin film; sol-gel method; coprecipitation method