【作者】 王芳平；

【导师】 武光明；

【作者基本信息】 北京化工大学 ， 材料科学与工程， 2010， 硕士

【摘要】 随着科学技术的发展,钛酸钡薄膜作为特殊形态的材料,已成为微电子、信息、传感器、光学等技术的基础,并广泛渗透到当前科技的各个领域。钛酸钡薄膜的制备方法主要有物理方法如射频磁控溅射、脉冲激光沉积和分子束外延等,化学方法如溶胶-凝胶法、有机金属化学气相沉积(MOCVD)法和水热法等。物理方法大多需要真空的工作环境,对仪器的要求比较高,一般的实验室难以达到其要求。而化学方法相对比较简单,不要求大型的仪器设备。本文构思、设计、装配了甩胶喷雾热分解制备薄膜装置,并通过试验升级改造,最后定型了设计。采用自行设计的甩胶喷雾热分解设备探索钛酸钡薄膜的制备,试验采用乙酸钡、钛酸四丁酯为主要原料制备钛酸钡溶液,以石英片、Si片为衬底材料,并结合热重分析(TG)、晶体结构(XRD)、表面形貌(SEM)、薄膜厚度(台阶仪)以及半导体测试仪等,来研究其制备条件如退火温度、升温温度、退火时间转速等对薄膜结构、表面形貌影响及其电学性能,也通过制备钛酸钡薄膜检验新设计装备的可行性和性能。实验结果表明,研制的甩胶喷雾热分解装置可以制备钛酸钡薄膜。退火温度、退火时的升温速度、退火时间、转速等对BaTiO3薄膜的结构形貌都有一定的影响,制备薄膜的最佳条件：衬底温度150℃,喷嘴距离为20mm,载气流量为1L/min,退火温度700℃,升温速度5／min,保温60min,转速4000r/min。经过700℃热处理,薄膜在1KHz频率,293K温度测试条件下,相对介电常数为198,并且介电常数随温度的相对变化率较小。本论文通过常用的磁控溅射方法制备了钛酸钡薄膜,测量其介电常数并与甩胶喷雾热分解方法制备的钛酸钡薄膜进行比较,前者的介电常数更低。更多还原

【Abstract】 With the development of the technology, BaTiO3 thin film, as a special material, has already been a base for microelectronics, communication, sensor, optics and penetrated into many parts of the science field. There are many physical methods to prepare BaTiO3 thin film, such as radio-frequency magnetron sputtering, pulsed laser deposition, MBE and many chemical methods such as Sol-Gel, metalorganic chemical vapor deposition(MOCVD), hydrothermal and so on.. Generally, the physical methods need vacuum environment, which are so strict to the apparatus that current laboratory can hardly achieve it. Compared with physical technologies, the chemical technologies are much easier and do not need complicated equipments.In this paper, we designed and assembled the device of spin spray pyrolysis, which was upgraded and improved through experiments, and finally finalized the design. BaTiO3 thin films were explored by the device of spin spray pyrolysis made at home. BaTiO3 precursor solution was made using tetrabutyl titanate and barium acetate as raw materials. Quartz and Si wafers were used as substrates. The effects of preparation conditions such as anneal temperature, heating rate, annealing time and rotational speed on the structure, surface morphology and electrical properties of the film were investigated with TG (thermogravimetry), XRD (crystal structure), SEM, step profiler (film thickness) and capacitance. The feasibility and performance of equipment were also tested by the preparation of barium titanate thin films.The results show that the spin spray pyrolysis device can prepare BaTiO3 thin film successfully. Anneal temperature, heating rate, annealing time and rotational speed have certain effects on the structures and surface morphologies of BaTiO3 thin films. The best conditions for preparing BaTiO3 thin films were as follows:the substrate temperature, nozzle distance, gas flow, anneal temperaturew, heating rate, annealing time and rotational speed were 150℃,20 mm, 1L/min,700℃,5/min,60min and 4000r/min, respectively. The dielectric constant of the thin film annealed with 700℃is 198 measured at 1KHz and 293K. The change rate of dielectric constant with temperature is relatively small.Barium titanate thin films were prepared with magnetron sputtering method in this paper, the dielectric constant of which was also measured. Comparing with the barium titanate thin film prepared by spin spray pyrolysis, the dielectric constant of the former was much lower.更多还原