NICKEL FILM ORIENTATION CHANGE BY NITROGEN ION-BOMBARDMENT DURING DEPOSITION

The influence of nitrogen ion bombardment during e-beam triode ion pla ting of nickel on the microstructure and film orientation has been inv estigated. The deposition variables explored were the ion current dens ity and deposition rate while the substrate temperature (ambient), par tial pressure of nitrogen (3 x 10(-4) Torr) and substrate bias potenti al (4.5kV) were constant. The orientation and growth morphology change for films about 1 mu m thick were determined by XRD, SEM and STM meth od. The preferred orientation changes from (111) to nearly complete (2 00) as a function of ion to atom arrival ratio (IAR), and was independ ent of the substrate type (amorphous or monocrystalline). The ion beam bombardment of films after deposition enables the in depth determinat ion of the nickel texture change during growth. For the highest IAR va lue the complete (200) texture was achieved at the beginning of deposi tion. The surface morphology (STM) and preferred orientation changes w ere correlated with ion to atom flux ratio and discussed on the basis of lowering the overall energy of the film. (C) 1997 Elsevier Science Ltd.