Nanoscale Etching of Metallic Perovskites Using STM

Abstract

In the present work we use a scanning tunneling microscope to modify the surface structure of epitaxial SrRuO 3 thin films. Point and line etching experiments were carried out in ultra-high vacuum, using tungsten tips. The point etchings showed that pulses fired at small (< 4.5V) bias voltages did not bring about any physical modifications of the film surface, while voltages in excess of 4.5 V led to etched holes accompanied by mounds. Moreover, well-defined line etching was achieved with a typical depth of approximately two unit cells and linewidths as small as 5 nm. The experiments demonstrate that a scanning tunneling microscope can be used for nanometer-scale patterning of SrRuO 3 thin film surfaces.

Current-controlled lithography on conducting SrTiO3−δ thin films by atomic force microscopy

“…[8][9][10][11][12][13][14][15][16][17][18][19][20] Direct etching of oxides has been reported in experiments performed by STM. 10,11,20 Bertsche et al 11 assert that field-induced corrosion of YBa 2 Cu 3 O 7−␦ ͑YBCO͒ occurs only in air and is a water-mediated electrochemical decomposition process; anyway, Takagi on YBCO ͑Ref. 10͒ and Dahl et al 20 on SrRuO 3 report that direct etching takes place also in ultrahigh vacuum conditions.…”

“…10,11,20 Bertsche et al 11 assert that field-induced corrosion of YBa 2 Cu 3 O 7−␦ ͑YBCO͒ occurs only in air and is a water-mediated electrochemical decomposition process; anyway, Takagi on YBCO ͑Ref. 10͒ and Dahl et al 20 on SrRuO 3 report that direct etching takes place also in ultrahigh vacuum conditions. AFM experiments on SrTiO 3 , 14-17 ͑La, Ba͒MnO 3 , 16,18 and YBCO ͑Refs.…”