c-Axis Aligned 3 nm Thick In₂O₃ Crystal Using New Liquid DBADMIn Precursor for Highly Scaled FET Beyond the Mobility–Stability Trade-off

Abstract

Oxide semiconductors (OS) are attractive materials for memory and logic device applications owing to their low off-current, high field effect mobility, and superior large-area uniformity. Recently, successful research has reported the high field-effect mobility (μFE) of crystalline OS channel transistors (above 50 cm2 V–1 s–1). However, the memory and logic device application presents challenges in mobility and stability trade-offs. Here, we propose a method for achieving high-mobility and high-stability by lowering the grain boundary effect. A DBADMIn precursor was synthesized to deposit highly c-axis-aligned C(222) crystalline 3 nm thick In2O3 films. In this study, the 250 °C deposited 3 nm thick In2O3 channel transistor exhibited high μFE of 41.12 cm2 V–1 s–1, V th of −0.50 V, and SS of 150 mV decade–1 with superior stability of 0.16 V positive shift during PBTS at 100 °C, 3 MV cm–1 stress conditions for 3 h.