锡薄膜等温氧化研究

采用电子束蒸发制备金属锡薄膜，将其在250—400℃温度范围内进行等温氧化，研究锡薄膜的热氧化动力学机制.采用台阶仪、扫描电子显微镜、俄歇电子能谱仪和X射线衍射仪等方法研究锡薄膜氧化过程中厚度、组分、结构等演变.实验结果表明，在250—400℃温度范围内，锡膜氧化后氧化层按抛物线规律生长；转变活化能为0.34eV；锡膜氧化受到氧扩散机制的控制.研究得到氧化层的生长首先从形成SnO相开始，随着氧化的深入，SnO相分解形成Sn₃O₄相，最后转变为SnO_{2<关键词：}

ISOTHERMAL OXIDATION OF TIN FILMS

The growth kinetics of the oxide film and oxidation mechanism on tin films prepared by the electron-beam evaporation in the temperature range of 250—400℃ by an isothermal process were investigated. Based on an X-ray diffraction, auger electron spectrum, scanning electron microscope and alpha-step instrument, the evolution of the structure, composition, morphology and thickness of the oxide on tin films has been studied. In the studied temperature region, the growth of the oxide film was found to obey a parabolic growth-rate law with an activation energy of about 0.34eV, and is controlled by the oxygen diffusion from the loose oxide. It is concluded that the growth of the oxide begins from the formation of a SnO phase，with the increase of the oxidation time, the SnO phase decomposes and a Sn₃O₄ phase forms due to the SnO thermal and chemical unstability, and the deeper oxidation transfers the Sn₃O₄ phase to a SnO₂ phase.