Abnormal growth of "giant" grains in silver thin films

Abnormal growth of "giant" grains in the millimeter range was observed in s ilver thin films with thicknesses of 2.0 and 2.4 mum. The effect depends on deposition temperature and deposition geometry. The microstructure and tex ture of as-deposited and annealed films have been characterized using X-ray , electron backscatter diffraction (EBSD) and focused ion beam (FIB) techni ques. Abnormal grain growth is found whenever a special texture is formed d uring film deposition. Otherwise normal grain growth occurs. The texture ty pe-and thus the grain growth mode-can he controlled by adjusting the proces s parameters. During abnormal grain growth, the initial (111) texture trans forms completely into (001). Growth of (111)-oriented grains stagnates at a size smaller than the film thickness with a non-columnar grain structure. This stagnation promotes orientation-selective growth of (001) grains. (C) 2001 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights res erved.