Modification of aluminum thin films

We have utilized several processing techniques to locally modify the superconducting transition temperature and the normal state resistivity of aluminum thin films. The techniques of ion implantation, application of a magnetic overlayer, and reactive ion etching have been used to fabricate S-N interfaces with controlled differences in transition temperatures and normal state resistances. Lithographic techniques and CF4 reactive ion etching at low power and pressure reliably produce two-dimensional S-N structures of desired dimensions in the limit where the transition temperatures and normal state electronic properties of the two regions are close to each other. © 1995 American Vacuum Society.