Infrared Laser Specroscopy of Radicals: A Diagnostic for Etching/Deposition Plasmas

这个RUI项目是在分析和表面的一般领域 化学和等离子体诊断领域。 无线电 硅烷和卤代硅烷中的高频和直流等离子体 气体广泛用于蚀刻和沉积薄膜 在半导体上。 理解、控制和优化 这些过程需要非侵入性的原位诊断 probes. 在这项研究活动中，红外吸收 光谱学将用于提供补充信息， 更常用的诊断技术如激光诱导 荧光光谱和光学发射光谱 瞬态多原子自由基物种的表征通常 存在于这些技术上重要的等离子体中 的能量 的红外吸收将用于识别物种 目前和相应的强度的反射将 用于确定其浓度。 获得的数据 这些实验将用于模拟化学事件， 等离子体对表面蚀刻和沉积很重要 工艺以及燃烧化学。 为了实现本研究的目标， 将用于测量高分辨率光谱的重要 等离子体产生的自由基，如SiF3、SiCl2、SiH2、HSiF和 Si2H4。 最初，自由基将在无线电中产生， 多程池中包含的高频或直流等离子体。 将采用频率、塞曼和浓度调制 提高最低可探测性， 自由基光谱与稳定分子的光谱不同。 以下 分析的光谱，等离子体反应器，模拟 半导体器件制造中遇到的条件 将被建造， 分布，以及旋转，振动和平移 温度将被测量为外部等离子体的函数 参数 这些测量应能使开发 一个化学反应的模型， 等离子体，还应建立红外吸收光谱 强大的等离子诊断仪

This RUI project is in the general area of analytical and surface chemistry and in the subfield of plasma diagnostics. Radio frequency and direct current plasmas in silane and halogenated gases are used extensively for etching and depositing thin films on semiconductors. The understanding, control, and optimization of these processes requires non-intrusive in situ diagnostic probes. In this research activity, infrared absorption spectroscopy will be used to provide complementary information to more commonly used diagnostic techniques such as laser induced fluorescence and optical emission spectroscopy for the characterization of transient polyatomic radical species typically present in these technologically important plasmas. The energies of the infrared absorptions will be used to identify the species present and the corresponding intensities of the absorptions will be used to determine their concentrations. Data obtained from these experiments will be used to model chemical events within the plasmas that are of importance to surface etching and deposition processes as well as to combustion chemistry. To achieve the goals of this research, a tunable infrared laser will be used to measure the high resolution spectra of significant plasma-generated radicals such as SiF3, SiCl2, SiH2, HSiF, and Si2H4. Initially the radicals will be generated in a radio frequency or direct current plasma contained in a multipass cell. Frequency, Zeeman, and concentration modulation will be employed to improve the minimum detectability and to differentiate the radical spectra from those of stable molecules. Following analysis of the spectra, a plasma reactor that simulates the conditions encountered in the manufacture of semiconductor devices will be built and the radical concentrations, spatial distributions, and rotational, vibrational, and translational temperatures will be measured as functions of external plasma parameters. These measurements should then enable the development of a model for the chemical reactions that take place in these plasmas and should also establish infrared absorption spectroscopy as a powerful plasma diagnostic.