The growth process of molecular nanocrystals on a solid surface was explored through the application of a vacuum evaporation technique. The combination of ultra rapid evaporation, a patterned intended surface, and a perylene-3,4,9,10-tetracarboxylic-3,4,9,10-dianhydride (PTCDA) buffer layer was found to be effective in producing small perylene nanocrystals (ca. 100 nm) at a high density (13.6 mu m(-2)). The prepared perylene nanocrystals exhibited characteristic fluorescence properties. The fluorescence spectra contained luminescence peaks attributed to a free exciton and self-trapped exciton, which were the result of nanometer-scale size effects. (c) 2005 Elsevier B.V. All rights reserved.