In this paper, we present the results of numerical simulations of inverted-staggered thin-film transistors (TFTs) with nanocrystalline silicon channel, using the semiconductor device simulator ATLAS from Silvaco. We study the influence of the density of the acceptor-like defect states concentration on the transistors' transconductance. Analysis of the free and the trapped carriers' concentrations at different gate voltages shows that the value of density of defect states determines the behaviour of nanocrystalline silicon TFTs between amorphous and polycrystalline silicon TFTs. (C) 2003 Elsevier Ltd. All rights reserved.