Measurement of the absolute cross sections for the electron collosion excitation of metastable states of rare-gases using a high-sensitivity FM-absorption methdo

利用半导体激光器作为可调谐吸收测量光源，发展了一种灵敏、准确地探测亚稳态和共振态激发态稀有气体原子的方法。然后，通过扫描激光波长，分析了Ar、Kr和Ar的吸收谱线的超精细结构和线形，并导出了从线吸收数据导出激发态原子的绝对密度所必需的碰撞展宽系数和位移系数。通过对电子漂移管的改进，建立了一套用于电子群实验的装置，该装置配备了超高真空系统，可以提供较长时间的较高和稳定的光电流。本文用漂移管和激光吸收技术相结合的方法，测量了Ne、Ar、Kr和Ar的亚稳能级和共振能级的激发系数随电场强度与气体密度之比的变化，并将测量的激发系数与用玻尔兹曼方程分析的计算结果作了比较。从比较中确定了激发态截面的绝对值.至于所获得的激发系数或截面的应用，我们试图将这些值用于模拟稀有气体与其它气体的混合气体放电，例如，用于彩色电视等离子体显示器和用于制备各种薄膜的等离子体CVD。

A sensitive and accurate method has been developed for the detection of the excited rare-gas atoms in the metastable and resonance levels using a diode laser as a tunable light source for the absorption measurement. Then, the hyperfine structures and line shapes of the absorption spectral lines of Ar, Kr, and Xe have been analyzed by scanning the wavelength of the laser and the collision broadening- and shift-coefficients have been derived, which are necessary for the derivation of the absolute densities of the excited atoms from the line absorption data.On the other hand, a set up for the electron swarm experiment has been constructed by improving the electron drift-tube equipped with an ultra-high vacuum system which can supply relatively high and stable photo-current for a long period. By compbining the drift-tube and the laser absorption technique we have measured the excitation coefficients for the metastable and resonance levels of Ne, Ar, Kr, and Xe as functions of the ratio of the electric field strength to the gas density.The measured excitation coefficients have been compared with the calculated results obtained from the Boltzmann equation analysis using a trial set of cross sections for each rare-gas. From the comparison absolute values of the cross sections for the excited levels have been determined.As for the application of the obtained excitation coefficients or the cross sections, we have tried to use those values in the simulations of gas discharges in mixtures of rare-gases with other gases which are used, e.g., for the plasma display for a color TV and the plasma CVD for the preparation of various thin films.