Tuning the termination of the SrTiO3(110) surface by Ar+ sputtering

We report a scanning tunneling microscopy study on the SrTiO3(110) surface treated with Ar+ sputtering followed by annealing. Two types of termination coexist on the surface, which are spatially identified as the 4x1 reconstructed SrTiO layer and the O layer covered by Ti-rich oxide clusters, respectively. The relative areal ratio of the two types is tuned by sputtering dose reproducibly, and monophased surface with either SrTiO or O termination is obtained. The surface is stable at temperatures up to 1100 degrees C and under oxygen partial pressures from 6x10(-5) mbar to ultra high vacuum, providing us a flexible epitaxial growth template.