Materials Synthesis and Processing: Experimental and Theoretical Studies on Titanium Nitride Synthesis by Laser Assisted Processes

激光引起了全世界的极大兴趣，因为 它们作为许多科学和工程工具的多功能性 例如材料的加工和合成的应用。 之间 激光的各种应用，激光化学气相沉积 激光化学气相沉积（LCVD）和激光物理气相沉积（LPVD）技术可以 用于合成具有精确空间分布的材料薄层， 控制 激光诱导沉积（LID） 作为制备薄膜的上级技术的方法已经被 虽然已经证明，但很少有人能理解基本原理， 这样的过程。 因此，一个研究项目 包括实验研究和数学的发展 用于LID期间的膜形成过程的模型， 作为氮化钛（TIN）的研究，以了解 这些过程的机制，并建立一个科学基础， 激光辅助材料加工 的形态和化学计量 用于LPVP和LCVD的TiN沉积将是主要兴趣。 锡 由于其广泛的生物学特性， 应用于微电子、光电、 电子、工具和航空航天工业。 TiN的应用 薄膜作为Si和Al之间的扩散阻挡层（用于VLSI）， 经常观察。 实验研究包括测定 光学和电子性能和表征， 用于LID形成TiN膜的各种电子光学技术。 近地表温度和化学成分 还将确定沉积。 这些结果将用于 获得关于表面分解分数的信息，以及 电影中的集群大小。 化学动力学数据会 LPVD过程中气相中的反应速率定律， 在LCVD过程中的气固界面上， 提高LID期间的反应速率。 沿着实验 工程，数学研究将进行考虑 用于在高环境压力下沉积的连续介质力学，以及 通过使用蒙特卡罗（MC）模拟或分子动力学（MD） 用于在低环境压力（超高）下沉积技术 真空，超高真空），以模拟具有化学反应的粒子传输 在LID期间。 MC或MD模拟也可用于预测 团簇大小及其对膜质量的影响。 这样的模型 将有助于确定重要的工艺参数， 预测LID系统的性能，以设计和优化 具有最佳控制的LID系统。 研究工作可使改进的控制激光器- 用于半导体处理的基于薄膜的沉积方法 和耐磨涂层的生产。

Lasers have attracted considerable interest world wide because of their versatility as a tool for many scientific and engineering applications such as processing and synthesis of materials. Among various applications of laser, Laser Chemical Vapor Deposition (LCVD) and Laser Physical Vapor Deposition (LPVD) techniques can be used to synthesize thin layers of materials with precise spatial control. Although the potential of Laser Induced Deposition (LID) processes as a superior technique to produce thin films has been demonstrated, little has been done to understand the fundamentals of such processes. For this reason, a research project encompassing experimental studies and development of mathematical models for the film forming process during LID for a compound such as Titanium Nitride (TIN) is researched in order to understand the mechanism of such processes, and to develop a science base for laser-aided materials processing. Morphology and stoichiometry of TiN deposits for both LPVP and LCVD will be a major interest. TiN is chosen as the model material for the study for its wide application in various industries such as microelectronics, opto electronics, tool and aerospace industries. Applications of TiN thin films as a diffusion barrier between Si and Al (for VLSI) is often observed. The experimental studies include the determination of optical and electronic properties and characterization by various electron-optical techniques for TiN films formed by LID. The surface temperature and chemical composition near the point of deposition will also be determined. These results will be used to obtain information about the surface-decomposition fraction and the cluster size in the film. The chemical kinetic data will shed light on the reaction rate law in the vapor phase during LPVD and at the gas-solid interface during LCVD, and on the question of enhanced reaction rate during LID. Along with the experimental works, mathematical studies will be carried out by considering continuum mechanics for deposition at a high ambient pressure, and by using the Monte Carlo (MC) simulation or molecular dynamics (MD) technique for deposition at a low ambient pressure (Ultra High Vacuum, UHV) to model particle transport with chemical reaction during LID. MC or MD simulation can also be utilized to predict the cluster size, and its effect on the film quality. Such models will be useful to determine the important process parameters, to predict the performance of the LID systems, to design and optimum LID system with optimum control. The researched work may allow the improved control laser- based thin film deposition processes for semiconductor processing and the production of wear-resistant coatings.