SITE-SPECIFIC, SYNCHROTRON-RADIATION-INDUCED SURFACE PHOTOCHEMISTRY

This paper discusses recent research directed at understanding the nat ure of surface photochemistry driven by soft x-ray synchrotron radiati on (SR). The research is motivated by the potential of x-rays for both high spatial resolution and site specificity. Although a number of sy stems indicate the potential for site specificity, we chose to study t he system of SiF4/Ge because the adsorbate's photoabsorption spectrum is rich in structure near the Si 2p threshold (106 eV) while that of t he substrate is structureless. This allows us to differentiate substra te-induced effects from those of the adsorbate. By performing time-dep endent measurements of the changes induced in the photoemission spectr a by SR, we have found that this system's photochemistry is site-speci fic in the Si 2p region and have also determined the nature of the pro ducts produced by the reaction.