Nanostructured nickel oxide (NiO) thin films were prepared using pulsed laser ablation technique on heated quartz substrates under an oxygen partial pressure of 2 x 10(-3) mbar. X-ray diffraction (XRD) studies indicate enhancement in growth along (1 1 1) and (2 0 0) crystal planes with increase of substrate temperature. The atomic force microscopic (AFM) studies indicate a self-assembly of NiO nanocrystals having size similar to 84 nm, with a uniform height profile along the assembly for films prepared at a substrate temperature of 673 K. Formation of arrays of confined two-dimensional NiO layers in the films prepared at a substrate temperature of 473 K is also reported. The optical band gap and electrical resistivity of the films synthesized under different deposition conditions are also discussed. (c) 2007 Elsevier B.V. All rights reserved.