| The ferroelectric thin films possess excellent piezoelectric, ferroelectric, pyroelectric, electro-optical, and non-linearity optical properties. These features make them be applied widely in microelectronics, optoelectronics, integrated circuitry, and microelectromechanical system. With the development of thin film prepared technology, people have made Micro-sensors, FRAM devices, DRAM devices, pyroelectric infrared detectors, spatial light modulator, optical memory, and optical waveguide devices.Pb(Mg1/3Nb2/3)O3(PMN)is a typical relaxation-type ferroelectric, PbTiO3 ( PT ) is a normal tetragonal ferroelectrics. (1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3(PMN-PT)is by PMN and PT form a binary complex continuous solid solution. At high temperature, PMNT is the paraelectric phase. With the temperature decreasing and the PT content varying, the structure of PMNT changes from tetragonal to rhombohedra ferroelectric phase. The PMNT relaxor ferroelectric exist a morphotropic phase boundary (MPB) in the PT content ranges of 30% -35%. The content of PT was lower than those is rhombohedra structure, and the higher than those is tetragonal. Rhombohedra, monoclinic, orthogonal, and tetragonal co-exist near the MPB, where the PMN-PT material could be characterized with remarkable properties and make the focus of attention.In this study, PMN-0.26PT thin films were prepared on Si substrate with a LaNiO3 (LNO) buffer layer and Pt/Ti/SiO2/Si substrate with a LaSrCoO3 (LSCO) buffer layer by radio-frequency magnetron sputtering, respectively. We have successful prepared pure perovskite preferred orientations thin films by changing process parameters, such as target distance, power, atmosphere, pressure, deposition temperature, and sputtering time. In structure, we obtained both (100) and (110) orientations on different substrates. In properties, we analysis that the influence of structures and properties by varying substrate temperature. We found that PMN-PT thin film have more uniform and compact structure, and possess much larger pyroelectric coefficient and the optical constants on LNO/Si substrate at the deposition temperature of 500oC. The dielectric constant, loss value, remnant polarization, pyroelectric coefficient, refractive index, and band gap values of PMN-PT thin films are 470, 0.04, 17.2μC/cm2, 3.1×10-4 C/m2 K, 2.41, and 3.22eV, respectively. In the mean time, we also received the same outstanding properties on LSCO/Pt/Ti/SiO2/Si substrate at 500oC. The specific parameters show that the dielectric constant is to 3500, the loss value is 0.14, the remnant polarization value is up to 37μC/cm2, and the pyroelectric coefficient reaches 9.4×10-4 C/m2 K. The PMN-026PT films can be used in pyroelectric infrared detectors and storage areas for the excellent values, and the larger remnant polarization value make it is possible to replace the conventional PZT films.
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