Thin Solid Films, 75 (1981) 29-36 PREPARATIONAND CHARACTERIZATION 29 NUCLEATION AND INTERFACE FORMATION IN THIN FILMS G. S. A. SHAWKI, M. G. EL-SHERBINY AND F. B. SALEM Department of Mechanical Design and Production, Faculty of Engineering, Cairo University, Cairo (Egypt) (Received May 22, 1980;acceptedJuly 7, 1980) In this paper we present the results of an experimental investigation into the nucleation and growth of ion-plated films. Transmission electron microscopy was used to study the nucleation of ultrathin silver films (10-400 A thick) deposited on carbon films about 50 A thick. Test results reveal that the formation of the ion-plated films is dominated either by direct deposition onto previously implanted nuclei or by the formation of new nuclei. The effect of ion implantation is to minimize the now well-known liquid-like behaviour of the deposited films. Furthermore, continuous ion-plated films can be produced with lower thicknesses than continuous films conventionally deposited in a vacuum. 1. INTRODUCTION The development of the ion-plating technique put an end to many problems traditionally associated with thin surface films ~'2. The exceptionally strong adherence of ion-plated films is the main reason for the present superiority of these films over conventionally deposited coatings 2-4. Furthermore, this technique is now finding a wide range of new potential applications in tribology and in corrosion protection where conventional films have failed. Although it is generally accepted that the physical properties of surface films are dependent on their structures 5' 6, it nevertheless appears that available data on ion- plated films are still quite limited 7' 8. Although a considerable amount of work on nucleation, growth and microstructure has already been published for conven- tionally deposited films6' 8, 9, very little is yet known of the microstructure of 1on- plated films6' 1 o. Furthermore, these investigations of ion-plated films did not cover film formation (nucleation and nuclei growth), in spite of the fact that the problem of film-substrate adhesion is basically interfacial and is dominated by the mechanism of nucleation s . The present work is concerned with the role played by high energy particles in the nucleation mechanism, which in turn influences film-substrate adhesion, especially in the case of mutually incompatible materials. Because of the high resolution needed for the study of such phenomena, transmission electron microscopy is generally used 9. Unfortunately the ion-plating 0040-6090/81/0000-0000/$02.50 © ElsevierSequoia/Printed in the Netherlands