ZnO nanorods were coated conformally with aluminum oxide (Al2O3) material by atomic layer deposition (ALD). The ZnO nanorods were first synthesized on a Si(I 0 0) substrate from ball-milled ZnO powders by a thermal evaporation procedure. Al2O3 films were then deposited on these ZnO nanorods by ALD at a substrate temperature of 300degreesC using trimethylaluminum and distilled water. Transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM) images of the deposited ZnO nanorods revealed that amorphous Al2O3 cylindrical shells surround the ZnO nanorods. These TEM images illustrate that ALD has an excellent capability to coat any shape of nanorods conformally. (C) 2003 Elsevier Science B.V. All rights reserved.