Step distribution on vicinal SrTiO3(001) surfaces

We have investigated distributions of unit-cell-high steps on SrTiO3(0 0 1) vicinal surfaces using scanning tunneling microscopy. We have estimated the terrace width distributions of SrTiO3(0 0 1) surfaces annealed at 800 degreesC for various misorientation angles smaller than 4degrees. By comparing the obtained terrace width distributions with theoretical predictions, we have shown that a long range repulsive interaction and a short range attractive interaction act between steps. The step distribution on the surfaces of misorientations smaller than 2degrees is governed only by the repulsive interaction and regularly stepped surfaces are formed, while the effect of the short range interaction on the surface morphology becomes significant for larger misorientation angles. (C) 2004 Elsevier B.V. All rights reserved.