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题名	薄膜生长过程及表面特性研究
作者	齐红基
学位类别	硕士
答辩日期	2003
授予单位	中国科学院上海光学精密机械研究所
导师	邵建达
关键词	生长 薄膜 分形 计算机模拟
其他题名	The Study of Growth Process and Surface Characteristics of Thin Film
中文摘要	随着固态高科技产业如集成电路、固体发光及激光器、磁记录材料及器件等的迅速发展，薄膜科学和技术也得到了飞速发展。一方面体现在新的制膜工艺不断涌现，控制测量技术的不断提高；另一方面表现在对薄膜生长中热力学及动力学行为的研究不断深入。不同的沉积工艺下薄膜生长动力学过程相差较大，引起薄膜内部微结构的不同，最终导致薄膜性能差异。生长界面的形貌是薄膜内部微结构的外在表现，对于薄膜表面形貌的深入了解可以更为深入的研究薄膜生长过程，从而达到控制薄膜性能的目的。论文首先综述了已有的关于薄膜初始生长阶段的研究成果，包括对成核、团簇生长、合并、渗析过程的研究。在此基础上提出利用薄膜表面特征来研究薄膜生长机理的想法。薄膜生长包含大量的随机过程，从统计学角度出发研究薄膜表面形貌是行之有效的方法，因此引入描述随机表面的一阶和二阶统计特性，如高度概率分布函数、自相关函数、高度-高度相关函数等来定量描述薄膜表面。把分形思想引入到薄膜生长中来，引入定量揣述分形表面参数-标准偏差粗糙度（Interface width）、生长指数（Growth exponentt）、粗糙度指数（Roughness exponent）等。深入了解已有的薄膜生长理论模型（Edwards-Wilkinson模型、Kordar-Parisi-Zhang（KPZ）模型、Mullins扩散模型等）中各个部分对．应的热力学及动力学过程，并在此基础上研究薄膜的生长机理。研究了离子束溅射工艺下非晶基底表面金属Ti薄膜的生长，利用原子力显微镜（AFM）测量其表面形貌，发现薄膜的生长为各向同性且表面具有典型的分形特征。综合AFM测量数据和分形概念，对薄膜表面作出了定量描述，并求出粗糙度指数、水平相关长度、标准偏差粗糙度等参数。结合已有的薄膜生长理论模型，得到此工艺条件下薄膜生长可以用Kuramoto-Sivashinsky模型来描述的结论。在上述工作的基础上，对于离子束溅射、磁控溅射、电子束蒸发三种工艺条件ZrO_2薄膜生长表面形貌及生长机制进行研究。结果表明，温度对表面颗粒的大小有较大影响，温度较高时表面颗粒较大，反之，颗粒较小。另外，沉积在基底表面的原子能量及沉积过程的稳定性对薄膜表面形貌也有较大影响。对于离子束溅射和磁控溅射ZrO_2薄膜生长可以用Kuramoto-Sivashinsky（K-S）模型来描述，对于电子束蒸发制备的ZrO_2薄膜，可以用Mulllns扩散模型来描述。在薄膜生长模型的基础上编写了薄膜实时生长程序，能够给出薄膜表面高度的实时演化过程，并对模拟的结果进行了定量分析，得到描述表面的参数与其它方法得到的结果一致。在对本论文工作总结的基础上，提出了一些关于薄膜生长新的研究方向，为后续工作做下铺垫。
英文摘要	With the rapid development of high-technology industry such as integrated circuit, solid-state luminescence, laser and magnetic recording materials, great progress has been made in science and technology of thin film. On the one hand, the new technology in preparation of the thin film, control and measurement comes forth one by one. On the other hand, the studies to thermodynamics and dynamics in the growth of thin film have been'made more thoroughly and comprehensively. Under different deposition technology, the dynamic process of thin film growth varies greatly, which leads to different microstructures and properties. The dynamics and thermodynamics can be considered deeply by means of the intensive study of the growth interface. Then, the characteristics of thin film can be controlled through changing the deposition technology, or deposition parameters. Firstly, the thesis reviews the initial growth process of thin film, including the nucleation, the growth of culser, coalescence, and percolation. On the study of initial growth of the thin film, the idea that the characteristics of the surface morphology are used to investigate the growth mechanism of thin film is developed. The growth process of thin film is full of random factors, so it is reasonable to study the surface morphology of the thin film on the base of statistics. In the thesis, the first-order and second-order statistical functions of random process such as the surface height distribution function, auto-correlation function, height-height correlation function, etc. are used to describe the growth interface of thin film quantitatively. The fractal idea is introduced to the growth of thin film. Furthermore, the parameters such as the interface width, the growth exponent, and the roughness exponent are used to describe the surface of thin film quantatively. All items of the growth model, such as Edwards-Wilkinson model, Kardar-Parisi-Zhang model, Mullins dissfusion model, etc. which represent the thermodynamic or dynamic process, are investigated in detail, and used to distinguish the growth mechanism of thin film. The growth of titanic thin films prepared by ion beam sputtering on BK7 substrates is studied. The surface morphology is measured using atomic force microscopy (AFM). The images show that surface is isotropic and self-affine. The surface can be quantitatively described by the roughness exponentα, the lateral correlation lengthξand the interface width w. The roughness exponentαis measured to be 0.72, which gives the related local surface fractal dimension Ds=2.28. From these values, we suggest that the growth of Ti thin film can be described by using a noisy Kuramoto-Sivashinsky equation. On the basis of above analysis, the surface morphology and the growth mechanism of ZrO_2 thin films prepared on BK7 substrates by ion beam reactive sputtering, magnetron reactive sputtering and electron beam evaporation, are investigated respectively. The surface morphology also is studied using atomic force microscopy. It is also found that the temperature of substrates has great effect on the morphology of grown interface during the deposition of films. Under higher deposition temperature, the grain size is bigger, whereas the grain size is smaller. Besides, the energy of atoms deposited on the surface of substrates also has some influence on the surface morphology of thin films. The mechanism of film growth is different under different conditions. In the case of ion beam reactive sputtering and magnetron reactive sputtering, the interfaces of films are determined by stochastic deposition, desorption and diffusion effect of atom or atomic clusters on the interface. The sputtering growth process can be described by a noisy Kuramoto-Sivashinsky equation. But for electron beam evaporation, desorption effect of atom or atomic clusters can be neglected, then the dynamic behavior of growth may be described by Mullins diffusion model. The real-time growing program of thin film on the basis of the growth models has been compiled, and can give and save 256-bitmap (BMP) and height data of surface morphology. The height data can be used to analysis the simulation results quantitatively. The analysis results are consistent with other methods. In the end, some new research contents have been put forward.
语种	中文
内容类型	学位论文
源URL	[http://ir.siom.ac.cn/handle/181231/16567]
专题	上海光学精密机械研究所_学位论文
推荐引用方式 GB/T 7714	齐红基. 薄膜生长过程及表面特性研究[D]. 中国科学院上海光学精密机械研究所. 2003.

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