Surface preparation of (110) oriented pure and Nb doped SrTiO3 single crystal substrates by microwave assisted hydrothermal method

Abstract We present a simple and fast microwave-assisted hydrothermal etching process for (110) oriented pure and Nb doped SrTiO 3 substrates. An annealing in oxygen atmosphere at 1000 °C after the etching in both deionized water and ammonia solution resulted in single-terminated surface for pure SrTiO 3 . In the case of niobium-doped substrates, such a surface could be realized only through etching in ammonia solution and subsequent annealing at 1100 °C. Observed step height of a /√ 2 nm in the topography by atomic force microscopy suggests [(SrTiO) 4 + ] or (O 2 ) 4 − termination. This realization of conducting/non-conducting, singly-terminated surface is of interest in the growth of layered multifunctional oxide heterostructures on SrTiO 3 (110).