Threshold Energy Densities to Generate Photoelectrons

To determine the appropriate energy density for the UV exposure its upper and lower limits were investigated. 

The upper limit of the energy density eas is determined by the onset of glass melting and evaporation, which corresponds to the ablation threshold (Sect. 8.2.2), which has to be avoided. The precise value of eas varies and depends on the type of interactions between glass and the radiation which in turn depends on laser wavelength [67]. She determined the upper limits of the 

The UV-exposure parameters affects compositional changes in glass, i.e. the breakage of chemical bonds, change of valency of sensitive polyvalent cations but also the generation of vacancies in the oxygen part of the network. The following exposure parameters are important  

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