Infrared laser radiation effects on XeF₂ interaction with silicon

Abstract

The presence of the laser radiation field on a silicon surface has been shown to influence the XeF2-silicon reaction rate. It is observed that the radiation enhancement in the surface reaction yield depends on the laser power, but is independent of the CO2 laser wavelength or the partial pressure of the active gas in the pressure range of 10 -4-10-5 Torr. A model based on the variation of the sticking probability of XeF2 on Si as a function of fluorine surface coverage modified by the laser radiation is proposed to account for the experimentally determined characteristics of the gas-solid system. The results show that the laser-enhanced chemical process may not be due entirely to the thermal effect. Furthermore, the study provides a better understanding for the laser induced interaction between SF6 and silicon, and for the fluorine-silicon surface chemistry in general. The radiation effect by the infrared photons is also compared with those induced by energetic electrons and ions. © 1981 American Institute of Physics.