Improved Performance and Operational Stability of Solution-Processed InGaSnO (IGTO) Thin Film Transistors by the Formation of Sn–O Complexes

Abstract

Solution-processed indium gallium tin oxide (InGaSnO, IGTO) thin film transistors (TFTs) are investigated as promising low-cost and stable materials for high-performance amorphous oxide semiconductor (AOS)-based TFTs in display applications. After tailoring the metal cation composition in IGTO thin films, the IGTO (7:1:1) AOS TFT shows a saturation mobility and current on/off ratio of 2.13 cm 2 V −1 s −1 and 2.55 × 10 7 , superior to the IGZO TFT. It was found that the threshold voltage (V th ) shifts of IGTO TFTs with higher Sn molar ratios became gradually diminished both under the positive bias stress (PBS) test, from +7.3 to +1.1 V, and under the negative bias stress (NBS) test, from −2.83 to −0.94 V, due to the increased concentration of Sn−O complexes with relatively higher bonding energies within IGTO thin films. X-ray photoelectron spectroscopy (XPS) analysis also reveals that IGTO thin films with higher Sn composition ratio tend to effectively suppress the formation of oxygen vacancy, which consequently led to the improved stability of IGTO-based TFTs under the gate bias stress. Therefore, these results can be the basis for improving the characteristics of IGTO semiconducting channel systems for low-cost switching devices in the display applications.

Component Distribution Regulation in Sn‐Pb Perovskite Solar Cells through Selective Molecular Interaction

“…The unshifted main peak of Sn 2+ in SnSO 4 verifies its high stability in air. Their bonding energy of Sn 3d electron and stability (SnSO 4 >SnF 2 >SnI 2 ) is consistent with the degressive bond energy of Sn-O (528 kJ mol −1 ), [46] Sn-F (467 kJ mol −1 ) [47] and Sn-I (235 kJ mol −1 ) [48] bond. Therefore, introduction of SO 4 2− into Sn-based perovskite could suppress the spontaneous oxidation of Sn 2+ during film deposition and even in the final device for a longer period.…”

Enhancement of the Electrical Performance and Bias Stability of RF-Sputtered Indium Tin Zinc Oxide Thin-Film Transistors with Vertical Stoichiometric Oxygen Control

“…To clarify the mechanism under PBS and NBS, the proposed energy band diagrams during the stress are shown in Figure . In the case of the PBS, a positive Δ V th occurs due to electron trapping at the interface of the insulator/semiconductor under the electric field. , The interfacial acceptor-like defect sites and neutralized oxygen vacancies (V o + + e – → V o and V o 2+ + 2e – → V o ) can change the trap levels at both the interface and the ITZO channel layer as shown in Figure a,b. The results indicate that the oxygen CCL can effectively prevent the absorption of O 2 and decrease defects at the interface of insulator/semiconductor, as shown in Figure b.…”

Tungsten-Doped Indium Tin Oxide Thin-Film Transistors for Dual-mode Proximity Sensing Application

“…Magnetron-sputtered amorphous gallium-doped ITO (ITGO) devices show μ FE of 25.6 cm 2 /(V s) (27.8 cm 2 /(V s)) and V th of 0.21 V (−12.6 V) after annealing at 200 °C (350 °C) . Solution-processed ITGO transistors exhibit μ FE of 2.13–4.47 cm 2 /(V s), I on / I off ratio of 10 3 –10 7 , and V th between 12.72 and −10.41 V . Another work on solution-processed ITGO transistors has μ FE between 11.5 and 40 cm 2 /(V s) and I on / I off ratio between 10 8 and 10 4 .…”

“…W 4f peaks centered at 35.2 eV (4f 7/2 ) and 37.4 eV (4f 5/2 ) are observed in ITWO films in Figure d, verifying the existence of W element as W 6+ ions in doped ITO thin films. Peaks of O 1s can be resolved into three peaks of O I , O II , and O III , which are centered at 529.8, 531.1, and 532.1 eV, respectively (Figures e and S5). In oxide semiconductor films, the O I peak is assigned to O 2– ions combined with metal ions, O II is associated with oxygen-deficient states, and O III is related to OH – impurities.…”