Surface treatment for forming unit-cell steps on the (0 0 1) KTaO3 substrate surface

A method for the preparation of unit-cell-high steps on the (1 0 0) surface of KTaO3 has been developed. The effects of various surface treatments on the (1 0 0) KTaO3 surface, specifically the chemical etching and annealing characteristics, are discussed. Surface step formation was observed for KTaO3 single-crystals that were subjected to buffered HF etching followed by annealing in air. The resulting surface morphology of (0 0 1) KTaO3 was examined using atomic force microscopy (AFM). The role of etching time and annealing temperatures in determining the resulting step structure, roughness, and particulate formation on the KTaO3 surface is discussed.