Theoretical sputtering yields of Al and Mg targets in physical vapor deposition processes

Abstract

Calculations of sputtering yields are performed for aluminum and magnesium target materials with the use of a homemade software based on the analytical expression of Garcia-Rosalès. The theoretical yield of magnesium is about twice the value related to aluminum in accordance with the experimental ratio of the Mg/Al deposition rates. We show that the deposits of the same materials must be subjected to densification followed by resputtering phenomena when a bias voltage is set to the substrates. These predictions are confirmed by atomic force microscopy observations, especially for magnesium deposits owing to their texture and the high sputtering yield of this material.