Nano-fabrication of organic molecules at liquid/solid interfaces is a promising method to form nano-structures of thermally unstable molecules on surfaces. Perylene-3,4,9,10-tetracarboxylic-dianhydride mono-molecular layer was formed on HOPG (0001) surface by vacuum-deposition as a canvas layer for nano-fabrication. After a droplet of I-octylbenzene solution of 3imino-4,5,6,7-tetrachloroisoindolin-1-one (ITCII) was placed on the surface, an STM tip was inserted into the droplet and a part of the canvas layer was scratched by the STM tip by increasing tunneling current. The scratched area was found to be immediately covered by ITCH molecules. In such way, ITCH mono-molecular layer with a designed shape could be fabricated. Structures of the formed layer are discussed in comparison to that of freely adsorbed layer. (C) 2004 Elsevier B.V. All rights reserved.