The Novascan PSD-UV4 Ozone Cleaner is effective for creating atomically clean surfaces. Applications are e.g. cleaning of semiconductor wafers, QCM-D sensors, AFM tips, or SEM/TEM samples. It is equipped with a mercury vapor UV lamp that generates UV light at wavelengths of 184.9 and 253.7 nm.
Molecular O2 is dissociated into two ground state O atoms by the 184.9 nm UV light and ozone (O3) is produced. Atomic oxygen is also produced when ozone is dissociated by the absorption of the 253.7 nm light. In addition, the 253.7 nm wavelength is useful for exciting or dissociating contaminant molecules. The excited contaminant molecules, and the free radicals produced by the dissociation of contaminant molecules, react with atomic oxygen to form simpler volatile molecules (such as CO2, H2O, N2, etc.) which desorb from the surface.