Atomic control of SrTiO3 surface for perfect epitaxy of perovskite oxides

Interaction of nanostructured metal overlayers with oxide surfaces

“…Kawasaki et al [152] have developed a wet chemical etching method to prepare the TiO 2 -terminated surface. It has been found that etching of prepolished SrTiO 3 (100) substrates in NH 4 F-buffered HF (BHF) solutions selectively removes surface SrO groups as well as calcium impurities leaving the surface terminated with Ti and O [152,153,371]. The reproducibility of the surface etching process has been improved through hydroxylation of the topmost SrO layer, which enhances the etching-selectivity of SrO relative to TiO 2 in a BHF solution [91,372].…”

Vacant-Site Octahedral Tilings onSrTiO3(001), the(13×13)R33.7°Surface,

“…A bewildering large number of different reconstructions have been experimentally observed on the SrTiO 3 surface including a series of (n×n) reconstructions on the (111) surface [1], (n×1) and (1×n) reconstructions on the (110) surface [2] and an even larger number for the (001), namely, the (1×1) [3][4][5][6][7][8][9][10], (2×1) [4,8,9,[11][12][13], (2×2) [8][9][10][14][15][16], c(4×2) [11,14,17,18], c(4×4) [4,8,16], (4×4) [16], c(6×2) [11,12,[17][18][19], (6×2) [18], (√5×√5)R26.6º [16,[20][21][22][23], (√13×√13)R33.7º [12,16] (RT13 hereafter) plus many more [24] which may only be locally stable such as a (4√2×√2)R45º.…”

In situ reduction of (100) SrTiO3

“…Also, according to previous studies, when the sample is heated to temperatures higher than 600°C in ultra high vacuum, (10 -10 ) carbon and water contamination disappear from the surface [8,9]. This allows us to study the samples by two different surface probes: PES and LEED, since the sample presents enough conductivity to be studied by these techniques.…”