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During exothermic reactions of atomic hydrogen or deuterium on a silver surface hot charge carriers are produced which have been observed by using Ag/ p-Si͑111͒ Schottky diodes. Thin film devices provide a means to bring a charge detector as close to the reaction site as the mean free path of the charge carriers. In the case of a p-doped substrate the Schottky barrier works as a high-pass energy filter for hot holes. The authors have therefore produced large area Schottky diodes with film thicknesses of up to 30 nm varying the thickness to rule out any influence of this device parameter. Those diodes were then exposed to beams of hydrogen atoms and deuterium atoms produced in a hot capillary source. Gas exposures do not affect the Schottky barrier height significantly. While exposing the samples to defined atom fluxes, the closed-loop current was monitored in real time. It shows that the current is proportional to the flux of atoms impinging on the surface. The authors have found hydrogen to generate 3.7 times more chemicurrent than is created during reactions with deuterium. Theoretical predictions of nonadiabatic energy dissipation using the electronic friction model agree well with the experimental results.

Optical and electrical properties of highly nitrogen-doped ZnO thin films grown by plasma-assisted molecular beam epitaxy Electron-cyclotron-resonance plasma etching of the ZnO layers grown by molecular-beam epitaxy Dry etching processes for bulk-single crystal zinc oxide ͑ZnO͒ and molecular beam epitaxy ͑MBE͒ grown ZnO have been investigated using inductively coupled plasma ͑ICP͒ of CH 4 and SiCl 4 based plasma chemistry. The CH 4 -based chemistry showed a higher etch rate than the SiCl 4 based chemistry, presumably due to the formation of highly volatile metal organic zinc compound. The influence of base pressure, radio frequency table power, and ICP power on etch rate was studied. Auger electron spectroscopy has been employed to examine the surface stoichiometry of etched ZnO using both plasma chemistries. Furthermore, with optimized process parameters, the effect of plasma etching on the optical properties of MBE grown ZnO film is studied. An enhancement of the band edge luminescence along with almost complete suppression of defect level luminescence in hydrogen-containing plasma treated ZnO film has been observed.