Direct evidence for stress-induced texture evolution and grain growth of silver thin films upon thermal treatment and self-ion bombardment

Common failure mechanisms in microelectronics, such as electromigration, creep and fatigue, can be positively influenced by microstructure optimization. In this paper a combination of post-deposition heat treatment and self-ion bombardment is proposed as a valid candidate to gain control over the microstructure of (1 1 1) fiber textured thin silver films. Irradiation can induce a strong in-plane texture and hence lead to biaxially textured films through a. process of selective grain growth. Moreover, we report microstructural stability of the irradiated regions over a wide range of temperatures (up to 600 degrees C), in contrast to non-irradiated portions of the film, which underwent abnormal growth of the (1 0 0) out-of-plane oriented grains, and a consequent texture change, at temperatures as low as 195 degrees C. The thermal stress induced in the film upon heat treatment was quantified in situ and its role in texture change elucidated. (C) 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.