The adhesion of thin metallic films to silicon substrates is shown to improve following irradiation with a flux of either 21.2‐eV (He I) 10.2‐eV (H Lyman &agr;) photons. The improved adhesion is similar to that found following MeV energy ion irradiation and keV energy electron irradiation, adding support to the view that electronic excitation and/or ionization and precursors to the stronger bonding configuration.