Microstructure investigation of initial formation of the Pd2Si-Si interface by TEM and ion channeling techniques

Abstract

Recent synchrotron-radiation experiment have established that the formation of the Schottky barrier at some transition metal-Si interface is essentially completed upon metal deposition of the first few monolayers. One problem of basic importance is the structural morphology and metal atom distribution of the initial silicide-Si interface. To complement our studies on the electronic and electrical characteristics, transmission electron microscopy (TEM), reflection electron microscopy (REM) and ion channeling techniques were used to investigate the microstructure of the initial Pd2Si-Si interface.Samples were prepared in UHV chember by e-beam evaporation of about 30-80 Å Pd on Si (100) or (111) substrates at room temperature then annealed at 200°C in various times to form Pd2Si. Back-etching of the Si substrates was finished with CP-4 solution. Samples were examined using a JEOL 200 CX microscope with TEM and REM mode.Fig. 1 is a high resolution lattice image of Pd2Si on (111) Si and a diffraction pattern. The amount of Pd deposited was estimated to be 80Å by ion back scattering