分子束弛豫谱研究Ge(111)表面与氯分子热反应动态学

Dynamics of Thermal Reaction of Ge(111)Surface with Molecular Chlorine Using Molecular Beam Relaxation Spectrometry

本文用分子束弛豫谱研究了Ge(111)表面与氯分子热反应动态学。采用种子束技术,发现增加氯分子的入射平动能,将有效地增加Cl_2与Ge表面的化学蚀刻反应。对分子束弛豫谱的数据分析表明,在表面温度T_s为700—900K的范围内,GeCl_2为该反应体系的唯一产物,它的脱附过程是蚀刻反应的速率控制步骤;并且测得脱附活化能E_d为66.0±2.0kJ·mol^(-1)。此外,对该化学蚀刻的反应机理进行了讨论。

The dynamics of thermal reaction of Ge(111) surface with chlorine molecules has been studied using molecular beam relaxation spectrometry (MBRS). The experimental investigation with seeded beam technique has pointed out that the chemical etching reaction of Ge surface by chlorine can be obviously enhanced with increasing incident translational energy of the chlorine molecules. The only reaction product GeCl_2 was observed in the Cl_2-Ge(111) thermal reaction at the surface temperature over a range of 700 to 900K. The analysis of MBRS data has shown that the desorption of the reaction product is the rate-limiting step of the reaction, The measured desorption activation energy of GeCl_2 is 66.0±2.0kJ·mol^(-1). Based on the result a possible mechanism for the chemical etching reaction has been proposed.