Ba
b>0.6b>Sr
b>0.4b>TiO
b>3b> films were deposited
by pulsed laser deposition on orthorhom
bic REScO
b>3b>(1 1 0) (RE=Dy, Gd) single-crystal su
bstrates. Films were investigated for their growth mode, crystalline quality, and strain states. Su
bstrates were treated prior to growth to produce atomically flat surfaces having wide terraces (≈200 nm) and clear unit-cell-high steps. Atomic force microscopy and reflection high-energy electron diffraction indicated that the films grew epitaxially in a two-dimensional (2D) layer-
by-layer mode. X-ray diffraction showed that all films (200 nm thick and less) were coherently/orthorhom
bically strained to the su
bstrate according to the epitaxial relationship: (0 0 1)
b>filmb>
![short parallel short parallel](http://www.sciencedirect.com/scidirimg/entities/2225.gif)
border="0">(1 1 0)
b>substrateb>; [1 0 0]
b>filmb>
![short parallel short parallel](http://www.sciencedirect.com/scidirimg/entities/2225.gif)
border="0">[0 0 1]
b>substrateb> (and [0 1 0]
b>filmb>
![short parallel short parallel](http://www.sciencedirect.com/scidirimg/entities/2225.gif)
border="0">[1 1¯ 0]
b>substrateb>). (0 0 2) rocking curves were 17 and 20 arcsec wide for films grown on RE=Dy and Gd, respectively.These films have rocking curve widths and dislocation densities that are several orders of magnitude lower than a film grown on SrTiO
b>3b> (0 0 1).