In view of its low barrier height to n-type Si, ErSi2 has potential applications as an infrared detector, as low-resistance ohmic contacts and as source/drain regions in Schottky barrier MOSFETs. Although there is a substantial body of work on ErSi2 grown on Si(111), there are relatively few published papers on the growth and properties of ErSi2 on Si(100). In order to develop a CMOS-compatible process, we have studied the growth of ErSi2 using a multi-source, UHV magnetron system to sputter-deposit 20 nm Ti/(10–50) nm Er bilayers on chemically cleaned n-Si(100) substrates followed by ex-situ rapid thermal annealing in N2. Highly oriented ErSi2 in the hexagonal phase was formed at an annealing temperature of 400°C with ErSi2 (100) Si(100). The Ti overlayer and the unreacted Er were selectively etched in HF and HNO3, respectively, leaving behind an ErSi2 layer with a smooth surface morphology, a uniform bulk composition and a planar ErSi2/Si interface. Results of electrical sheet resistance and Schottky barrier height measurements on these layers will be reported.