Li Wenzhi, Ma Zhuang, Gao Lihong, Wang Fuchi
School of Material Science and Engineering, Beijing Institute of Technology, Beijing 100081, China.
National Key Laboratory of Science and Technology on Materials under Shock and Impact, Beijing 100081, China.
Materials (Basel). 2015 Mar 17;8(3):1176-1186. doi: 10.3390/ma8031176.
La₁SrTiO (LST) has been studied in many fields, especially in the field of microelectronics due to its excellent electrical performance. Our previous theoretical simulated work has suggested that LST has good dielectric properties, but there are rare reports about this, especially experimental reports. In this paper, LST was prepared using a solid-state reaction method. The X-rays diffraction (XRD), scanning electron microscope (SEM), broadband dielectric spectroscopy, impedance spectroscopy and photoconductive measurement were used to characterize the sample. The results show that the values of dielectric parameters (the relative dielectric constant ε and dielectric loss tanδ), dependent on temperature, are stable under 350 °C and the value of the relative dielectric constant and dielectric loss are about 52-88 and 6.5 × 10, respectively. Its value of conductivity increases with rise in temperature, which suggests its negative temperature coefficient of the resistance. In addition, the band gap of LST is about 3.39 eV, so it belongs to a kind of wide-band-gap semiconductor materials. All these indicate that LST has anti-interference ability and good dielectric properties. It could have potential applications as an electronic material.
镧锶钛矿（LST）已在许多领域得到研究，尤其是在微电子领域，因其具有优异的电学性能。我们之前的理论模拟工作表明LST具有良好的介电性能，但关于此方面的报道很少，尤其是实验报道。本文采用固态反应法制备了LST。利用X射线衍射（XRD）、扫描电子显微镜（SEM）、宽带介电谱、阻抗谱和光电导测量对样品进行了表征。结果表明，介电参数值（相对介电常数ε和介电损耗tanδ）随温度变化，在350℃以下是稳定的，相对介电常数和介电损耗值分别约为52 - 88和6.5×10。其电导率值随温度升高而增加，这表明其具有负电阻温度系数。此外，LST的带隙约为3.39 eV，因此它属于一种宽带隙半导体材料。所有这些表明LST具有抗干扰能力和良好的介电性能。它作为一种电子材料可能具有潜在的应用。
