Study of Contact Resistance in Amorphous Zinc Oxide Based Thin-Film Transistors

This work focuses on the use of various contact-modification approaches to lower contact resistance (Rc) in a-IGZO (Amorphous-Indium Gallium Zinc Oxide) bottom gate top contact (BGTC) thin-film transistors (TFTs) using the two-probe method both in linear and saturation regions respectively. This study investigates the contact resistance of Al source/drain electrodes treated with carbon nanotubes (CNT), molybdenum trioxide (MoO
3
), and both MoO
3
/CNT in TFT. The contact resistance of the contact/semiconductor interfaces was examined using the TCAD simulator tool. The lowest contact resistance of 0.004 MΩ is obtained in the optimized structure of MoO
3
/Al/CNT as the carrier injecting buffer layer (CNT) and thin layer of MoO
3
increases the charge carrier (electron) concentration of the IGZO at the interface of the device. This paper explores the study of Ohmic/Schottky contacts on organic transistors by extracting transistor parameters (total resistance, probe potential, and contact resistances) from OTFT transfer characteristics.