Epitaxial Growth and Stability of C49 TiSi2 ON Si(111).

Abstract

ABSTRACTEpitaxial TiSi2 films have been grown by molecular beam epitaxy (MBE) on atomically clean Si(111)-orientated substrates. The growth procedure involves the ambient temperature deposition of Ti films of 50Å thickness and annealing to 800°C. In situ low energy electron diffraction (LEED) and Auger electron spectroscopy (AES) techniques have been used to monitor the TiSi2 formation process. The epitaxial films have been identified as the C49 metastable phase by both Raman spectroscopy and electron diffraction. Plan view transmission electron microscopy shows three different connected island morphologies. The individual island structures are single crystal and are grown epitaxially with different crystallographic orientations. The orientational relationship of the largest islands is given by [3 1 1] C49 TiSi2//[112]Si and (130) C49 TiSi2//(l1 1)Si. High resolution transmission electron microscopy (HRTEM) cross-section shows a coherent interface extending over several hundred angstroms.