We have produced millimetre-sized areas of self-ordered, sub-micron scale, complex structures in iron-doped single crystal lithium niobate, using the combined interaction of laser light and etching with acid. We report here the factors that influence the formation of the structures, and illustrate the types of structure that may be formed, using images taken by a scanning electron microscope (SEM) and subsequent Fourier Transform analysis of those images. We also consider the physical processes which initiate and control the growth of the structures. (C) 2004 Elsevier B.V. All rights reserved.