薄膜中界面相变机制的研究

项目名称： 薄膜中界面相变机制的研究

项目编号： No.11274218

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 数理科学和化学

项目作者： 王江涌

作者单位： 汕头大学

项目金额： 74万元

中文摘要： 薄膜材料中的相变不同于块体材料，薄膜中界面自由能的变化对于相变的发生起着关键，甚至是决定性的作用。本项目以金属/非晶半导体及金属/金属的薄膜体系为研究对象，从理论和实验两个方面，探索发生在这两类薄膜体系中的界面相变，包括金属诱导非晶半导体晶化及界面化合物形成的机制。理论方面，通过界面热力学的方法计算体系的界面自由能，并比较在不同条件下体系自由能的变化，确定体系可能存在的最稳定相，以及随条件改变最有可能发生的相变过程，达到在一个统一的热力学框架下，全面、定量地解释发生在薄膜材料中界面相变机制的目的。实验方面，侧重于在理论计算的基础上，特别是针对相变的成核条件及界面化合物形成的过程，设计一些有针对性的实验，以验证理论计算的结果。由该项目发展起来的一套研究方法，可以推广应用于其它薄膜体系中界面相变的分析，研究结果可以为更好地利用薄膜材料提供具有指导性的建议。

中文关键词： 薄膜；界面相变；扩散；深度剖析；定量分析

英文摘要： Phase transformations occurred in thin solid film are different from that in bulk materials. In thin film, the Gibbs free energy change at interface plays an important and even a decisive role in the phase transformation. In this project, the investigated systems are chosen as metal/amorphous semiconductor and metal/metal thin solid films and the goal is to investigate both theoretically and experimentally the mechansims of phase transformation occurred at interface in these two systems, including the metal-induced crystallization of amorphous semiconductor and the compound formation at interface. In theory, the Gibbs free energy values at interfaces will be first calculated based on the interfacial thermodynamical theory. Then the most stable phases and the possible procedures of phase transformation will be evaluated by comparing the changes of the interfacial Gibbs free energy under different conditions. By these theoretical calculations, the mechansims of interfacial phase transformation in thin films can be interpreted detailedly and quantitatively in the framework of a unified thermodynamics. In experiment, some designed experiments will be conducted to testify the calculation results, in particular, focusing on the requirements of nucleation and the procedures of phase transformation. The research metho

英文关键词： thin film；interface phase transformation；diffusion；depth profiling；quantitative analysis