Size Effects in Internal Friction of Nanocrystalline Aluminum Films

Al thin film is extensively used in micro-electromechanical systems (MEMS) and electronic interconnections; however, most previous research has concentrated on their quasi-static properties and applied their designs on larger scales. The present study designed a paddle-like cantilever specimen with metal films deposited on the upper surface to investigate the quasi-static properties of Al thin film at room temperature under high vacuum conditions at microscopic scales. Energy loss was determined using a decay technique in the oscillation amplitude of a vibrating structure following resonant excitation. Grain size and film thickness size were strictly controlled considering the quasi-static properties of the films. This study found that the internal friction of ultra-thin and thin Al films was more dependent on the grain boundaries than film thickness.

Наноструктурирование при наклонном напылении алюминия

Formation of regular arrays of nanorods with high aspect ratio (length to transverse size) has been found in the process of Al thin film growth at oblique angle deposition on silicon substrate by the method of electron beam evaporation. It was found that the optimal conditions for nanostructuring are realized at the inclination angle larger than 80 degrees.