Microfabrication of nanoscale cluster chains on a patterned Si surface

We have studied the formation of Cu clusters from Cu atoms deposited onto a Si (111) surface patterned with (2–5 μm width) lines of photoresist. In addition to a thin Cu layer on the exposed Si surface, large (∼150 nm) clusters nucleate at the boundary between the Si and the resist strips, which remain after removal of the resist by dissolution. The results show how it is possible, using the resist to collect deposited atoms, to assemble nanoscale cluster structures with a precision (∼150 nm feature size) which is much better than the resolution of conventional optical lithography (∼μm linewidth).