Surface structure and morphology induced by ultrathin Ti films on 6HSiC(0001) and (0001̄)

Abstract

We used scanning tunneling microscopy (STM) to study the structure, morphology and reaction when ultrathin Ti films (<10 monolayers) were deposited in situ on 6HSiC(0001) Si-terminated and (0001̄) C-terminated surfaces. Volmer-Weber growth of Ti islands was observed when deposition was carried out at room temperature. Annealing the surfaces at 700°C produced an ordered (√3 × √3) phase and a disordered phase on the (0001) surface while the island structure remained unchanged on the (0001̄) surface. Further annealing at 850°C caused the ordering of the disordered phase on the (0001) surface into a second (√3 × √3) phase while the island structure on the (0001̄) surface was replaced by large domains of (2√3 × 2√3) geometry. Structural models were proposed to correlate the observed ordered phases with compositions of the reaction products.