Ion bombardment effects on internal stress of magnetic thin films

Abstract

This study examined the effect of argon ion bombardment on the internal stress of a nickel film. As a means of expressing the effect of ion bombardment, we propose an ion bombardment parameter based on the momentum of the ions. The magnitude of the ion momentum determined from the plasma potential was not dependent on the sputter power. With the increase in sputter power, the increase in the impingement frequency of nickel atoms onto the substrate was greater than the increase in the impingement frequency of Ar+ ions. It has become evident that the ratio of impingement argon ions to nickel particles onto the substrate mainly affects the variation in the ion bombardment parameter in relation to the sputter power. Thus, it has been demonstrated that the internal stress of a nickel film can be predicted using the ion bombardment parameter. © 2010 The Japan Institute of Metals.