Research on Polycrystalline Films for Micro- and Nano-Systems

Polycrystalline films are used in a wide array of microand nano-scale devices, for electronic, mechanical, magnetic, photonic and chemical functions. Increasingly, the properties, performance, and reliability of films in these systems depend on nano-scale structure. In collaborative research with a number of SMA Fellows, Associates, and students, our group is carrying out research focused on probing, modeling and controlling nano-scale structural evolution during both vaporphase and solid-phase polycrystalline film formation. In particular, high-sensitivity in-situ and real-time stress measurements are being used to study atomic scale forces and to characterize structure formation and evolution at the nano-scale. In other collaborative research, the affects of controlled structure and multi-film architectures on properties, such as piezoelectric characteristics and electromigration-limited reliability, are being explored. Through these interrelated activities, basic principles of the science and engineering of nano-scale materials are emerging.