Low‐temperature migration of Si into Au/Pt thin films on Si substrates with an interposed Cr layer, investigated by two methods of depth analysis

By optical detection of excited sputtered particles, depth analysis of a multilayer film on a Si substrate was carried out and low‐temperature migration of Si was studied. For complementary information, Rutherford backscattering analysis of all samples was performed. A comparison between the two methods shows that the optical method is well suited for Si migration studies. As a result, it was found that Si penetrated through a 100‐A‐thick Cr film into the top metal layers of Pt and Au after heat treatment in the temperature range 350–400 °C. It was also found that a 400‐A Cr film acted as an effective barrier for Si migration under similar conditions.