P‐1.2: Improvement of Mobility and Reliability of a‐IGZO TFTs by Dual‐Gate Driving

Abstract

In this work, a IGZO thin‐film transistor with double‐gate structure is studied to realize high mobility and strong reliability simultaneously. Enhancement‐mode operation that is essential to the constitution of a low‐power digital circuitry and high current demand of mini‐LED and micro‐LED display is easily achieved when the top and bottom gate electrodes are tied together. The device mobility and the subthreshold swing are improved from 16.2 cm2/Vs and 0.29V/dec to 22.4 cm2/Vs and 0.24V/dec, respectively, compared with the single‐gate (SG) structure. High mobility is attributed to the dual channel of double gate coupling. Finally, the mechanism of NBTiS improvement also has clarified in terms of energy band and electric field of the double gate structure.