Enhancement of In-Sn-Ga-O TFT performance by the synergistic combination of UV + O3 radiation and low temperature annealing

Highly Stable Oxide Thin-Film Transistor-Based Complementary Logic Circuits under X-ray Irradiation

“…When the total dose of X-rays increased from 0 to 100 Gy, the area percentage of O Vac s increased from 15.2 to 21.8%, revealing the generation of additional O Vac within the IGZO thin films by X-ray irradiation. In IGZO, O Vac acts as a shallow donor state and provides free electrons; − therefore, an increase in O Vac in the X-ray-irradiated IGZO thin films can explain the slight negative shift in the transfer curve of n-type IGZO TFTs after X-ray irradiation. Figure S3 shows the XRD patterns of the IGZO thin films obtained before and after the X-ray irradiation.…”

“…When X-ray is irradiated to the SnO X TFT, the increase in the O Vac and Sn 4+ components in SnO X TFT occurs, where O Vac can act as a hole trap state located close to the VBM and increased Sn 4+ reduces the hole carrier concentration that leads to the shift of Fermi level for p-type ( E Fp ) from near VBM toward CBM. In the case of IGZO TFT, the increase in the O Vac is induced by X-ray irradiation, where O Vac coordinated with a small number of cations can act as shallow traps or deep traps such that O Vac can be ionized to O Vac 2+ by energy, whereas O Vac coordinated with a large number of cations can act as a shallow donor state that provides free electrons. ,, This induces the shift of Fermi level for n-type ( E Fn ) toward CBM, which is demonstrated in the energy band diagrams of SnO X and IGZO TFTs before and after X-ray irradiation in Figure S5. In addition, we extracted the noise margins from the fabricated CMOS inverter before and after X-ray irradiation at a dose of 100 Gy, where the noise margin is the figure of merit for diagnosing the stability of the logic inverter when subjected to signal interference …”

High-Performance Indium Gallium Tin Oxide Transistors with an Al2O3 Gate Insulator Deposited by Atomic Layer Deposition at a Low Temperature of 150 °C: Roles of Hydrogen and Excess Oxygen in the Al2O3 Dielectric Film

“…To resolve this problem, high- k dielectric materials such as alumina (Al 2 O 3 ), hafnia (HfO 2 ), and zirconia (ZrO 2 ) have been studied in the context of TFTs because the higher dielectric constant ( k ) values of these materials enable compensation of the capacitance with films thicker than a silicon dioxide (SiO 2 ) film. − However, it is challenging to fabricate electrically stable AOS TFTs because low-temperature (<200 °C) processing results in inclusion of impurities from source materials and unintentional formation of defects such as vacancies, interstitial oxygen defects, and hydrogen-related complexes. For this reason, AOS TFTs prepared at low temperatures suffer non-negligible hysteresis and bias instability. , Obviously, it is of great importance to identify the origin of bias instability for low-temperature processed AOS TFTs. The displacement direction of the threshold voltage ( V TH ) for AOS TFTs under gate bias stress (BS) generally depends on the polarity of the gate bias.…”

“…For this reason, AOS TFTs prepared at low temperatures suffer non-negligible hysteresis and bias instability. 12,13 Obviously, it is of great importance to identify the origin of bias instability for low-temperature processed AOS TFTs. The displacement direction of the threshold voltage (V TH ) for AOS TFTs under gate bias stress (BS) generally depends on the polarity of the gate bias.…”

Inkjet-Printed Top-Gate Thin-Film Transistors Based on InGaSnO Semiconductor Layer with Improved Etching Resistance

“…As a result, the printed InGaSnO semiconductor layer is almost not affected during printing the following gate dielectric layer. Although vacuum-processed InGaSnO films with the advantage of excellent electrical and optical properties has been reported before [19][20][21][22][23][24][25][26], it is for the first time to investigate the chemical corrosivity of inkjet-printed InGaSnO semiconductor films, to the best of our knowledge. in the mixture solvent of 2-methoxyethanol and ethylene glycol with a volume ratio of 1/1.…”