红外激光诱导SF6与硅和钨的表面化学反应

本文研究了TEA CO_2激光诱导SF_6与单晶硅和金属钨的表面化学反应。实验结果表明这些反应的反应率与激光频率之间具有明显的依赖关系, 在频率为942.2 cm~(-1)处反应率呈极大值。对于SF_6-Si体系, 反应率与硅的不同晶面有关, 在相同条件下Si(100)面与SF_6的反应率大于Si(111)面。对于SF_6-W体系, 测定了激光能量密度和脉冲辐照次数与反应率之间的关系, 其反应阈值为1 Jcm~(-2), 并测得该反应的速率与SF_6分压呈一级反应关系。同时, 还讨论了上述反应的机理, 认为气态振动受激的六氟化硫分子与被激光激活的固相表面之间的相互作用是反应的主要过程。

Infrared Laser Induced SF6 Interaction with Silicon and Tungstun Surfaces

TEA CO_2 laser induced Si-SF_6 and W-SF_8 interactions have been studied and the surface reaction yields have been determined as a function of the laser frequency. The results show that the reaction yields depend strongly on the laser frequency and there is a maximum at the frequency of 942.4 cm~(-1), For Si-SF_6 system, the reaction yield also depends on the different planes of silicon single crystals and it shows that the Si(100) is more active than the Si(111) under the same experimental conditions. For W-SF_6 system, the reaction yields have been determined as a function of laser fluence and number of laser pulses. The results show that the reaction threshold is 1 J cm~(-2) at the laser frequency of 942.4 cm~(-1) and the reaction rate is of first order in SF_6 pressure. These results impies that the infrared laser irradiation plays and important role in these gas-surface reactions and the main step might be the interaction between the vibrationally excited SF_6 molecules and laser stimulated solid surfaces.