Thin films of Bi2Te3 were grown onto CdTe(111)B by using molecular-beam epitaxy. Structural and transport properties were investigated by using in situ reflection high-energy electron diffraction, X-ray diffraction analysis, thermopower and Hall-effect measurements. The crystallinity and transport were found to be strongly affected by non-stoichiometry. The most stoichiometric sample had a high crystallinity, high thermopower and high electron mobility. However, films with excess Te had a reduced lattice constant, poorer crystallinity, reduced thermopower and reduced mobility. These observations could be explained in terms of antisite defects in which excess Te occupied Bi lattice sites and behaved as a n-type dopant.

Antisite Defects of Bi2Te3 Thin Films S.Cho, Y.Kim, A.DiVenere, G.K.Wong, J.B.Ketterson, J.R.Meyer: Applied Physics Letters, 1999, 75[10], 1401-3