CRYSTALLOGRAPHIC EVOLUTION OF MICROSTRUCTURE IN THIN-FILM PROCESSING .1. GRAIN-SIZE DISTRIBUTION

Processing parameters and the resulting properties of a material are l inked by the relationship between processing and microstructure. Chara cterizing the effect of processing variations on microstructure and de termining its origin are essential to advanced material development. I n this and a companion article, some readily applied techniques for pr oducing quantitative data on grain size and shape, as well as grain an d boundary crystallography, are described. The method described in Par t I utilizes transmission electron microscopy and image analysis to me asure grain size in large quantities (2000 to 3000 grains per sample), differentiated into orientation class subpopulation distributions. On application to Ni thin films produced by ion assisted deposition, the results have identified an orientation subpopulation that is predomin antly responsible for the larger grain sizes observed in films grown u nder high ion flux. Larger grain size and the development of a preferr ed orientation have both been associated with increasing ion flux duri ng growth, however, these results give the first experimental evidence connecting grain size and texture in these films.