He was employed at the Bell Aerospace Company, Buffalo, New York, from 1968-1971 and joined the faculty of Materials Science at the University of California, Berkeley and the staff of the Lawrence Berkeley Laboratory in 1971. The research is theoretical, and involves first-principles calculation and simulation of deformation processes in ultrahard materials. The specific materials of interest include transition metal carbides and nitrides and the diamond-like materials.
Plasticity is, in turn, controlled by the work hardening of the material.
Our current research addresses the work hardening of aluminum alloys and its relation to the deformation patterns developed during tensile elongation. Interfacial friction is strongly influenced by the topology of the metal surface. The active elements of microelectronic circuits communicate through narrow, thin-film metallic conductors that transport very high current densities. The high current densities drive mass diffusion which can lead to voiding and failure. We are investigating the rates and microstructural mechanisms of failure in narrow lines through electromigration testing of lines with controlled microstructure and high-resolution TEM analyses of failure sites.