超声分子束研究激光诱导Cl2和Ta表面反应动态学

本文研究了在三种不同波长的脉冲激光(365 nm, 560 nm和1064 nm)辐照下超声Cl_2分子束与多晶Ta表面的化学反应动态学. 由四极质谱和飞行时间增(TOF)测定了产物的质量分布和速度分布. 该反应的主要产物为TaCl, TaCl_2, TaCl_3及TaCl_4; 它们的TOF谱都可用Maxwell-Boltzmann分布拟合, 所得的平动温度分别在500 K—1500 K范围内. 测定了各种产物相对产率与激光能量密度和入的Cl_2分子平动能的关系. 此外, 对此气-固表面反应的机理进行了讨论。

SUPERSONIC MOLECULAR BEAM STUDIES ON THE DYNAMICS OF LASER-INDUCED Cl2-Ta SURFACE-REACTIONS

The supersonic molecular beam technique is used to study the dynamics of laser-induced surface reactions of Ta surface with chlorine at three different wavelengths (355, 560, 1064 nm). The mass and velocity distributions of the reaction products are determined by the time-resolved mass spectrometry. The observed time-of-flight(TOF) spectra of the products show that the main products are TaCl, TaCl_2, TaCl_3 and TaCl_4 and there is no TaCl_5 observed. Their TOF spectra can be fitted with Maxwell-Boltz-mann distributions at translational temperatures in the range of 500-1500 K. The effect of translational energy of incident Cl_2 molecules and laser fluences on the laserinduced Cl_2-Ta surface reactions at different wavelengths are presented. Finally, the possible reaction mechanism is discussed based on the experimental observations.