Design of an ultrahigh vacuum compatible system for studying the influence of acoustic waves on surface chemical processes

So far, there have only been very few studies on the effects of acoustic waves (AWs) on chemical processes involving the gas-solid interface. Acoustic induced desorption of residual gases has been shown to provide an alternative desorption route to the well established electron or photon induced and thermal excitation channels. It has also been shown that the catalytic activity of a thin film can be increased by acoustic excitation. A novel ultrahigh resolution tunable acoustic spectrometer has been designed and is described in this paper, capable of exciting a chemical system with narrowband AWs. A special UHV compatible sample holder has also been designed for the excitation of a metal single crystal with AWs, using an edge bonded transducer. For the first time, InterDigital Transducers with a thin metal single crystal bonded onto the piezoelectric substrate can be used to investigate acoustic induced desorption under UHV conditions.