Electrochemical polymerization of pyrene in boron trifluoride diethyl etherate (BFEE) produced oligopyrenes (pyrene oligomers) with repeat unit numbers of 2-15. The oligoyrenes grown at the working electrode are nanosheets with high crystallinity. As an array of microelectrodes or a semiconductive silicon wafer patterned with microelectrodes were used as the working electrode, a dendritic network of cyrstalline oligopyrene nanosheets was fabricated. The initially grown nanosheets on the microelectrodes act as nodes and the network with interconnects of the nanosheets grow from the nodes. The number and structure of the inconnectects can be controlled by the structure of the patterned electrode, the concentration of the monomer, the value of applied potential and the charge density used for electrochemical deposition. This is the first example of fabrication neuron-type network based on conductive organic nanosheets. (C) 2005 Elsevier Ltd. All rights reserved.