A new concept of vertical thin film transistor (TFT), called thin film transistor comb (TFTC), is proposed based on polycrystalline silicon (polysilicon) deposited at low temperature (T <= 600 degrees C). This structure, compatible with glass substrates, is designed to have up to 4 teeth and enables to get a high channel width W with a short channel length L. The channels of TFTC are made of a non-intentionally doped (NID) polysilicon layer between two in situ heavily-doped polysilicon layers; all these three layers are deposited by low pressure chemical vapor deposition (LPCVD) method. Electrical characteristics of TFTC show relatively high on-currents (I-ON) correlated with the geometric parameters. However, high off-currents (I-OFF) are also observed due to the large overlapping area between drain and source regions. (C) 2012 Elsevier Ltd. All rights reserved.