0.6V Threshold Voltage Thin Film Transistors With Solution Processable Indium Oxide (In2O3) Channel and Anodized High-[Formula Omitted] Al2O3 Dielectric

• Published in: IEEE electron device letters 2019-01, Vol.40 (7), p.1112
• Main Authors: Bhalerao, Sagar R, Lupo, Donald, Zangiabadi, Amirali, Kymissis, Ioannis, Leppaniemi, Jaakko, Alastalo, Ari, Berger, Paul R
• Format: Article
• Language: English
• Subjects: Aluminum oxide; Density; Electron mobility; Indium oxides; Metal oxides; Semiconductor devices; Thin film transistors; Threshold voltage; Transconductance; Transistors
• ISSN: 0741-3106; 1558-0563
• DOI: 10.1109/LED.2019.2918492

Low-voltage operation and low processing temperature of metal oxide transistors remain a challenge. Commonly metal oxide transistors are fabricated at very high processing temperatures (above 500°C) and their operating voltage is quite high (30–50 V). Here, thin-film transistors (TFT) are reported based upon solution processable indium oxide (In2O3) and room temperature processed anodized high-[Formula Omitted] aluminum oxide (Al2O3) for gate dielectrics. The In2O3 TFTs operate well below the drain bias ([Formula Omitted]) of 3.0 V, with on/off ratio [Formula Omitted], subthreshold swing (SS) 160 mV/dec, hysteresis 0.19 V, and low threshold voltage ([Formula Omitted] V. The electron mobility ([Formula Omitted]) is as high as 3.53 cm[Formula Omitted]/V.s in the saturation regime and normalized transconductance ([Formula Omitted]) is [Formula Omitted]/mm. In addition, the detailed capacitance–voltage (C–V) analysis to determine interface trap states density was also investigated. The interface trap density ([Formula Omitted]) in the oxide/semiconductor interface was quite low, i.e., [Formula Omitted]–[Formula Omitted] eV[Formula Omitted]cm[Formula Omitted], signifying acceptable compatibility of In2O3 with anodic Al2O3.