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Ferroelectric thin film materials with excellent piezoelectric, ferroelectric, pyroelectric, electro-optical and nonlinear optical properties can be widely used in microelectronics, optoelectronics, integrated ferroelectrics and micro-electro-mechanical system, become the research focus of the new functional materials and Integrated Devices. As thin film technology continues to evolve, has been made of micro-sensors, FRAM devices, DRAM devices, pyroelectric infrared detectors, spatial light modulator, optical disk storage, optical waveguide devices such as a large number of devices. Lead magnesium niobate (PMN) is a typical relaxation ferroelectric lead titanate (PT) is tetragonal normal ferroelectric body. (1-x) Pb (Mg 1/3 Nb 2/3 ) O 3-x PbTiO 3 (referred to as PMN-PT) is formed by the PMN and PT composite binary continuous solid solution. PMN-PT high temperature paraelectric phase structure as the temperature decreases and PT content changes, showing a ferroelectric phase change from the four winds to the tripartite. PT content of 30% -35% range memory in a quasi-phase boundary (MPB), PT content of less than MPB tripartite structure, higher than the phase boundary tetragonal structure in the phase boundary, the three parties, monoclinic, orthogonal and the Quartet heterogeneous structure coexist. PMN-PT near the MPB region has excellent performance, it has been the focus of attention and research focus. Paper, using a magnetron sputtering method, by using the type of the buffer layer (e.g., lanthanum nickel oxide, cobalt oxide, lanthanum strontium), respectively, Si and Pt / Ti / SiO 2 / Si substrate Preparation of PMN-0.26PT film. By optimizing the process of preparation of the buffer layer, including changing the substrate to target distance, the power, and the atmosphere, the pressure, the deposition temperature and the sputtering time, pure perovskite structure is supported by a preferential orientation film. From two aspects of the structure and properties of PMN-0.26PT film system. In structure, and in the LNO / Si and LSCO / Pt / Ti / the SiO 2 / Si substrate, respectively, supported by a thin film (110) and (100) preferred orientation. In terms of performance, respectively, from four aspects of the dielectric, ferroelectric, pyroelectric and optical depth research and a series of important performance parameters. LNO / Si substrate, we analyzed the influence of substrate temperature on the structure and performance. PMN-PT film has a more uniform and dense surface structure and greater pyroelectric coefficient and optical constants in the growth temperature of 500oC. We measured the dielectric constant of 470, a loss of value of 0.04, remanent polarization is 17.2μC/cm 2 , pyroelectric coefficient of 3.1 × 10 -4 C / m 2 K, a refractive index of 2.41, the band gap of 3.22eV. On the other hand, in the LSCO / Pt / Ti / SiO 2 / Si substrate, we have obtained a film having excellent performance at 500oC. Pyroelectric coefficient of 9.4 × 10 -4 2 > C / m 2 K. These merit, PMNT film can be applied to the pyroelectric infrared detectors and memory, larger remnant polarization it is expected to replace the traditional PZT thin film.
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