FORMATION OF NEW SURFACE-LAYERS ON CERAMICS BY ION-ASSISTED REACTION

Ar+ ions with 1 keV energy were irradiated on aluminum nitride in an O -2 environment and on aluminum oxide in a N-2 environment. AlON on AlN and AlN on Al2O3 are formed by the Ar+ irradiation in O-2 gas and N-2 gas environments, respectively, and the formation of new surface laye rs is confirmed on the basis of Al2p near core levels and O1s, N1s cor e levels XPS depth profile analysis. Cu (1000 Angstrom) films were dep osited by ion-beam sputtering on Ar+ irradiated/unirradiated AlN surfa ces, and the change of the adhesion strength was investigated by a scr atch test. Cu films deposited on the irradiated AlN under an O-2 envir onment showed higher bond strength than that on the unirradiated AlN. The improvement of bond strength of Cu films on the Al surface resulte d from the interface bonds between Cu and the surface layers. The bend ing strength of polycrystalline Al2O3 irradiated by Ar+ ions in N-2 en vironment was also increased and the formation of nitride layer on the alumina was confirmed. A possible new surface layer formation mechani sm on ceramics by the ion assisted reaction has been discussed in term s of surface analysis, chemical bond, and mechanical strength.