Abstract

The 7.9 eV photons of a F₂ laser (157 nm) induce direct photochemical desorption of hydrogen from a Si(111)-(1x1):H surface. The cross section of (1.2±0.8)x10^-20 cm² indicates that the optical process is more efficient than the recently discovered electron-stimulated process. For comparison, results are also reported for the 4.0 eV photons of a XeCl-excimer laser (308 nm), which initiate photothermal desorption.

© 1998 IEEE