The atomic structure of [00▪1]-tilt grain boundaries was investigated by using high-resolution transmission electron microscopy, and atomistic calculations. The high-resolution transmission electron microscopy was performed on [00▪1] fiber-textured thin films, grown onto quartz-glass substrates by pulsed-laser deposition. The [00▪1]-tilt boundaries observed in the films could be classified into 3 types: low-angle boundaries composed of irregular dislocation arrays, boundaries with {10▪0} facet structures and near-low Σ boundaries represented by symmetrical periodicity units. The atomic structure of the boundaries was considered, with attention being concentrated on a Σ = 7 boundary, in conjunction with atomistic calculations and high-resolution transmission electron microscopic image simulations. The Σ = 7 boundary consisted of multiple structural units that were very similar to the core structures of edge dislocations. Straight or zig-zag arrangements of the dislocation-like structural units also constituted other high-angle boundaries with symmetrical and {10▪0} facet structures. It was suggested that [00▪1]-tilt boundaries in ZnO could generally be described as being arrays of dislocation-like units.

Atomic Structure of [0001]-Tilt Grain Boundaries in ZnO - a High-Resolution TEM Study of Fiber-Textured Thin Films. Oba, F., Ohta, H., Sato, Y., Hosono, H., Yamamoto, T., Ikuhara, Y.: Physical Review B, 2004, 70[12], 125415