"Making Nanoscale Metal Features on Atomically Clean Silicon Surfaces with a Stencil"

J. Nogami and A. Linklater, University of Toronto, Canada

Nanometer scale metal features have been created in UHV on atomically clean silicon surfaces with a stencil. These features were subsequently characterized by scanning tunneling microscopy and scanning electron microscopy. The best feature edge definition achieved was < 10 nm. At the same time, the metal feature/silicon boundary showed significant spreading of a sub monolayer of metal beyond the deposited area, well beyond what can be accounted for by simple considerations of shadowing. This spreading varied for different deposited metals, and was also different on the Si(111) and the Si(001) surfaces. This spreading may pose a limit on the ultimate resolution that can be achieved for metal features deposited on atomically clean silicon surfaces. At the same time, deposition through a stencil combined with atomic resolution imaging provides opportunities to study surface diffusion and film growth behavior.