Extraction of Separated Source and Drain Resistances in Amorphous Indium–Gallium–Zinc Oxide TFTs Through C– V Characterization

Considering asymmetry caused by layout, process, and device degradation, separate extraction of the source and drain resistances, i.e.,RSandRD, respectively, from the total resistanceRTOTis very important in the design, modeling, and characterization of amorphous indium–gallium–zinc oxide (a-IGZO) thin-film transistors (TFTs). Due to the insulated gate structure, however, separate extraction is difficult through direct-currentI–Vcharacterization. In this letter, we propose a simple and useful technique for separate extraction ofRSfromRDin a-IGZO TFTs through a two-terminal parallel-modeC–Vtechnique. We experimentally verified the validity of the proposed technique by comparing the result with the source-to-drain resistance from theI–Vcharacteristics.