Depth microscopy at interfaces

High resolution depth microscopy with swift heavy ions is performed at the Munich tandem accelerator and its Q3D magnetic spectrograph using the elastic recoil detection technique. The method gives the possibility to analyze elemental and isotopic concentration profiles of light and medium heavy atoms in thin films and at interfaces. A monitor detector has been installed in the scattering chamber of the Q3D in order to get the relative elemental content for the high resolution depth profiles without absolute knowledge of beam current and charge yields. It is a detector telescope which consists of an ionisation chamber for energy loss and a silicon detector for a residual energy measurement in order to obtain the nuclear charge of the detected target atoms. Depth microscopy was applied for quantitative analysis of concentration profiles at the interfaces between a-Si : H and a-SiC : H layers. Hydrogen profiles can directly be compared to carbon and oxygen profiles showing an excess hydrogen content at the interface between the two layers.