Amorphous and nanocrystalline silicon films obtained by Hot-Wire Chemical Vapor Deposition have been incorporated as active layers in n-type coplanar top gate thin film transistors deposited oil glass substrates covered with SiO2. Amorphous silicon devices exhibited mobility values of 1.3 cm(2) V-1 s(-1),which are very high taking into account the amorphous nature of the material. Nanocrystalline transistors presented mobility values as high as 11.5 cm(2) V-1 s(-1) and resulted in low threshold voltage shift (similar to 0.5 V). (c) 2005 Elsevier B.V. All rights reserved.