Systematic investigation of the ion beam sputter deposition process of TiO2

提出的项目的总体目标是产生关于离子束溅射沉积过程的新知识，这将允许针对不同应用优化薄膜的薄膜性能。因此，它旨在为具有定制性能的薄膜的不断增长的需求做出贡献。预期的项目应大大扩展项目前的基础和成功执行的调查。前期项目对单原子材料（即Ag和Ge）离子束溅射沉积过程进行了全面系统的研究，即研究了工艺参数（一次离子能量、离子种类、离子入射角、极性发射角）、成膜粒子性能（溅射靶粒子和散射一次粒子的角分布和能量分布）与成膜性能之间的系统关系。在提议的项目中，这些系统的研究应扩展到多原子系统的溅射过程，因为预计单原子目标溅射的系统差异，或者例如，目标成分的优先溅射和多个溅射物种的产生，即原子，离子和分子的产生。不同的粒子种类暂时具有不同的角度和能量分布，它们对工艺参数有不同的依赖关系。到目前为止，还没有发表任何解决这些问题的结果。例如，选择TiO2作为考虑的材料。二氧化钛由于某些材料性质，即其光活性或光学性质，在技术上引起了人们的兴趣。正因为如此，二氧化钛被用作太阳能电池或光学多层涂层中的光催化剂。溅射法沉积TiO2有两种工艺方法。第一种方法是金属Ti靶的反应沉积。在这里，金属成分被溅射，而氧气作为工艺气体提供。第二种方法是直接溅射陶瓷TiO2靶材。在这种情况下，所有薄膜成分都从靶上溅射出来。因此，这两种方法不同于进入生长层的能量，这应该导致不同的薄膜性能。拟建项目应完成以下任务：实验测量成膜颗粒和成膜的性质，以及它们在系统工艺参数变化下的关系。这些实验应在直接沉积和反应沉积过程中进行。此外，还将进行溅射过程的模拟，这将有助于验证模拟代码，从而验证其在具体情况下的可用性。

The overall goal of the proposed project is the generation of new knowledge concerning the understanding of the ion beam sputter deposition process, which shall allow the optimization of film properties of thin films for different applications. Thus, it is intended to contribute to the growing demand for thin films with tailored properties.The intended project shall considerably extend the fundamental and successfully performed investigations from befor project. The previous project addressed the comprehensive and systematic investigations of the ion beam sputter deposition process of monoatomic materials (namely Ag and Ge), i.e. the study of the systematic relations between the process parameters (primary ion energy, ion species, ion incidence angle, polar emission angle), the properties of the film-forming particles (angular and energy distributions of sputtered target particles and scattered primary particles), and the film properties.In the proposed project these systematic investigations shall be extended to the sputtering process of multiatomic systems, because systematic differences in respect to sputtering of a monoatomic target are expected, or instance, preferential sputtering of the target constituents and the generation of more than one sputtered species, namely, the generation of atoms, ions and molecules. The different particle species tentatively possess different angular and energy distributions, which have different dependencies on the process parameters. So far, there have been published no results which have addressed these questions. Exemplarily, TiO2 is chosen as the considered material. TiO2 is of technological interest because of certain material properties, i.e. its photo activity or its optical properties. Because of that, TiO2 is used as photo catalyst, in solar cells or in optical multilayer coatings.There are two technological approaches for the deposition of TiO2 by sputtering. The first approach is the reactive deposition from a metallic Ti target. Here the metallic component is sputtered whereas the oxygen is provided as a process gas. The second approach is the direct sputtering of ceramic TiO2 target. In this case all film constituents are sputtered from the target. Thus, the two approaches differ from the energy entry into the growing layer, which should result in different film properties. The following tasks shall be done within the proposed project: The experimental measurement of the properties of the film forming particles and of the films, and their relations under systematic variation of the process parameters. These experiments shall be performed for both the direct and the reactive deposition process. In addition, simulations of the sputter process will be performed, which shall help to validate the simulation code and, hence, its usability in the concrete case.