“…HIN-film transistors (TFTs) based on amorphous oxide semiconductors (AOSs), like amorphous InGaZnO (a-IGZO), have been demonstrated to possess ultra-low offcurrent (I off ), steep subthreshold swing (SS), relatively high mobility, and low fabrication temperature, and thus are regarded as the most viable driving device for next-generation displays [1]. The overall competitiveness of AOSs further attracts extensive attention in large-area flexible electronics [2], low-power circuits [3], flexible chips [4], 3D stacked memories [5], and other back-end-of-line (BEOL) devices for 3D ICs [6]. These applications demand the AOS transistors with extremely downscaled channel length (L) and accordingly gate insulator (GI) thickness [7], [8].…”