Structural effect on electronic sputtering of hydrogenated amorphous carbon films

A large erosion (similar to 10(5) atoms/ion) of C and H from hydrogenated a morphous carbon films (a-C:H) is observed due to the bombardment of 150 MeV Ag13+ ions. The erosion rate is monitored on-line by elastic recoil detect ion analysis (ERDA) technique. From the set of four samples under study, tw o films show erosion of both C and H, whereas, only H depletion takes place from the other two films. The observed variation in sputtering yield in di fferent films is explained on the basis of structure and chemical environme nt of the films. It is shown in the framework of thermal spike model that t he thermal energy confinement due to smaller cluster or domain sizes of the film influences the erosion. Structure of the films is revealed by Raman s pectroscopy and is discussed on the basis of their Raman G and D modes. (C) 2001 Elsevier Science Ltd. All rights reserved.