Highly sensitive detection of H2O adsorbed on Si(111)7 x 7 and Si(100)2 x 1 surfaces by means of slow highly charged Xe ions

The proton yields from Si(111)7 x 7 and Si(100)2 x 1 reconstructed surfaces irradiated with slow (nu < 0.25 nu(Bohr)) highly charged Xe ions are obtained. H2O molecules adsorbed over time on the surfaces at room temperature, under ultra-high vacuum can be detected as an increase of the proton yield. For the Si(100)2 x 1 surface, the proton yield with HCI-irradiation time is discussed based on temporal variation of the H2O coverage. The proton desorption efficiency with Xe50+ is more than about ten times and twice as compared with Xe29+ and Xe44+, respectively. For the Si(111)7 x 7 and Si(100)2 x 1 surfaces, the proton yield in each time increases with the charge states q to the power of 6 and 4, respectively, and is changed with time with the power laws held on.

Automated summary

The study found that the proton yield on Si(111)7 x 7 and Si(100)2 x 1 surfaces increases over time when irradiated with slow, highly charged xenon ions. The proton yield on the Si(100)2 x 1 surface is related to HCI irradiation time and temporal variation of H2O coverage. The proton desorption efficiency is highest with Xe50+ compared to Xe29+ and Xe44+.