Use of the scratch test to measure changes in adhesion of Cr/Al2O3 due to ion beam mixing

Abstract

The scratch test is widely used to measure the adhesion of thin films to their substrates. The adhesion improvement with ion beam mixing is difficult to quantify, however, because the mixing process itself introduces changes into the system that affect the measurement of adhesion by the scratch test. This paper described the effect of ion beam mixing on the test parameters and analyzes the results of tests on ion bombarded chromium films on sapphire substrates. The measured force to remove the Cr film increased by more than 1900% due to the ion beam treatment. Changes in the system parameters account for an increase of less than 5%, leading to the conclusion that the ion beam treatment caused a major increase in the bond strength.