Series Of Thin-film Transistors Research Articles

Effective Contact Resistance of Zinc-Tin Oxide-Based Thin Film Transistors

We investigated different source/drain (S/D) electrode materials in thin-film transistors (TFTs) based on amorphous zinc-tin oxide (ZTO) semiconductors. The transfer length, channel conductance, and effective contact resistance between the S/D electrodes and the a-ZTO channel layer were examined. Total ON resistance (R(T)), transfer length (L(T)) and effective contact resistance (R(c-eff)) were extracted by the well-known transmission-line method (TLM) using a series of TFTs with different channel lengths. When the width of ZTO channel layer was fixed as 50 μm, the lengths were varying from 10 to 50 μm. The channel layer and S/D electrode were defined by lift-off process and for the S/D electrodes, indium-tin oxide (ITO), Cu, and Mo were used. The resistivity and work function values of electrode materials were considered when selected as candidates for S/D electrodes of ZTO-TFTs. The results showed that the ZTO-TFTs with Mo S/D electrodes had the lowest effective contact resistance indicating that ZTO-TFTs with Mo electrodes have better electrical performance compared to others.

Influence of molybdenum source/drain electrode contact resistance in amorphous zinc–tin-oxide (a-ZTO) thin film transistors

This paper investigates the feasibility of a low-resistivity electrode material (Mo) for source/drain (S/D) electrodes in thin film transistors (TFTs). The effective resistances between Mo source/drain electrodes and amorphous zinc–tin-oxide (a-ZTO) thin film transistors were studied. Intrinsic TFT parameters were calculated by the transmission line method (TLM) using a series of TFTs with different channel lengths measured at a low source/drain voltage. The TFTs fabricated with Mo source/drain electrodes showed good transfer characteristics with a field-effect mobility of 10.23cm2/Vs. In spite of slight current crowding effects, the Mo source/drain electrodes showed good output characteristics with a steep rise in the low drain-to-source voltage (VDS) region.

An investigation of contact resistance between metal electrodes and amorphous gallium–indium–zinc oxide (a-GIZO) thin-film transistors

This paper reports our investigation of different source/drain (S/D) electrode materials in thin-film transistors (TFTs) based on an indium–gallium–zinc oxide (IGZO) semiconductor. Transfer length, contact resistance, channel conductance, and effective resistances between S/D electrodes and amorphous IGZO thin-film transistors were examined. Intrinsic TFT parameters were extracted by the transmission line method (TLM) using a series of TFTs with different channel lengths measured at a low drain voltage. The TFTs fabricated with Cu S/D electrodes showed the lowest contact resistance and transfer length indicating good ohmic characteristics, and good transfer characteristics with intrinsic field-effect mobility ( μ FE- i ) of 10.0 cm 2/Vs.

Copper source/drain electrode contact resistance effects in amorphous indium–gallium–zinc‐oxide thin film transistors

AbstractThis paper focuses on the viability of low‐resistivity electrode material (Cu) for source/drain electrodes in thin film transistors (TFTs). The effective resistances between Cu source/drain electrodes and amorphous indium gallium zinc oxide (a‐IGZO) thin‐film transistors were examined. Intrinsic TFT parameters were extracted by the transmission line method (TLM) using a series of TFTs with different channel lengths measured at a low source/drain voltage. The TFTs fabricated with Cu source/drain electrodes showed good transfer characteristics with a field‐effect mobility of 9.64 cm2/Vs, and good output characteristics with steep rise in the low VDS region. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)