TEXTURE CONTROL IN THIN FILMS USING ION BOMBARDMENT

摘要

The development of texture in thin films under ion bombardment is believed to occur due to the preferential growth of the aligned grains in the film relative to the unaligned grains. The difference in growth rates between aligned and unaligned grains results in the development of texture with increasing thickness. Both out-of-plane (fiber) and in-plane texture can be controlled during ion bombardment. Experiments were performed to create a (110) out-of- plane texture in thin aluminum films and to create a (110) in-plane texture in niobium films. Results showed that the texture in both cases increases in strength with depth, and that for 500 nm Al films, the (110) texture was stronger than the thermodynamically-preferred (111) texture obtained by physical vapor deposition. Results confirm a texturing mechanism based on ion channeling and preferential sputtering.