Effects of 1,6-Bis(trichlorosilyl)hexane on the electrical characteristics of amorphous indium–gallium–zinc oxide thin-film transistors

Abstract

This study investigates the direct effects of the cross-linker 1,6-bis(trichlorosilyl)hexane (BTCSH) with the surface of amorphous indium–gallium–zinc oxide (IGZO) and its consequences for thin-film transistor operation. To elucidate the impact of BTCSH, a pristine device and a BTCSH-treated device were examined, the latter being fabricated by spin-coating a BTCSH-containing solution onto the pristine device and subsequently annealing at 200 °C to remove the solvent and retain only BTCSH. As a result, BTCSH-treated devices exhibited a lower threshold voltage (VTH) of −0.95 V, higher field-effect mobility (μFE) of 8.13 cm2/V s, and lower subthreshold swing of 0.24 V/dec compared to those of pristine devices. Under positive gate bias stress, the VTH shift decreased from 5.5 V in the pristine device to 4.0 V after BTCSH treatment. These improved performances and reliability are attributed to the reduction of weakly bonded oxygen and the formation of oxygen vacancies (VO) at the back-channel surface. Consequently, the reaction mechanism of the BTCSH cross-linker on the IGZO surface should be considered during process design, as it affects both defect states and device reliability.