Papers by Author: Sang Chul Lim

Abstract: We report the effects of instability with gate dielectrics of pentacene thin film transistors (OTFTs) inverter circuits. We used to the UV sensitive curable resin and poly-4-vinylphenol(PVP) by gate dielectrics. The inverter supply bias is VDD= -40 V. For a given dielectric thickness and applied voltage, pentacene OTFTs with inverter circuits measurements field effect mobility, on-off current ratio, Vth. The field effect mobility 0.03~0.07 cm2/Vs, and the threshold voltage is -3.3 V ~ -8.8 V. The on- and off-state currents ratio is about 103~106. From the OTFT device and inverter circuit measurement, we observed hysteresis behavior was caused by interface states of between the gate insulator and the pentacene semiconductor layer.

Abstract: We report on the fabrication of dual-gate pentacene organic thin-film transistors (OTFTs) using a plasma-enhanced atomic layer deposited (PEALD) 150 nm thick Al2O3 as a bottom gate dielectric and a 300 nm thick parylene or a PEALD 200 nm thick Al2O3 as both a top gate dielectric and a passivation layer. The threshold voltage (Vth) of OTFT with a 300 nm thick parylene as a top gate dielectric is changed from 4.7 V to 1.3 V and that with a PEALD 200 nm thick Al2O3 as a top gate dielectric is changed from 1.95 V to -9.8 V when the voltage bias of top gate electrode is changed from -10 V to 10 V. The change of Vth of OTFT with the dual-gate structure has been successfully understood by an analysis of electrostatic potential.