Aerosol deposition of zinc oxide (ZnO) nanoparticles was used to catalyze a silicon substrate site-selectively for a carbon nanotube (CNT) growth. An ambient spark discharge was used to produce aerosol ZnO nanoparticles, and the particle deposition on the substrate through a shadow mask was enhanced by thermophoresis. The ZnO-deposited substrate was then loaded into a chemical vapor deposition chamber, resulting in the formation of CNT/ZnO arrays. The turn-on field of an emission device constructed with the CNT/ZnO arrays was 1.7 V mu m(-1) at a current of 2 mu A, which was lower than that of the common CNT arrays. (C) 2012 Elsevier Inc. All rights reserved.