Loss of hydrogen from ion irradiated photoresist and a-C:H films

The loss of hydrogen (H) induced by ion irradiation, in photoresist AZ-1350J and in polymeric hydrogenated amorphous carbon (a-C:H) films, was determined by measuring the amount of H in the samples before and after the irradiations. The measurements were performed through the elastic recoil detection analysis and nuclear reaction analysis techniques. The ions and energies used covered a wide range of transferred electronic (S-e) and nuclear (S-n) stopping powers, from nearly pure S-e (400 keV N) to predominantly S-n (800 keV Xe). We observed that the emission of H as function of the fluence is a two exponential process for both samples: the first one for low fluences, and the second for medium and high fluences. This behavior is well explained by the bulk molecular recombination model, which assumes that hydrogen leaves the irradiated materials in molecular form. (C) 2004 Elsevier B.V. All rights reserved.