Investigation of the drain current shift in ZnO thin film transistors

The electrical characteristics of Zinc oxide (ZnO) thin-film transistors are analyzed to apprehend the effects of oxygen vacancies after vacuum treatment. The energy level of the oxygen vacancies was found to be located near the conduction band of ZnO, which contributed to the increase in drain current (ID) via trap-assisted tunneling when the gate voltage (VG) is lower than the specific voltage associated with the trap level. The oxygen vacancies were successfully passivated after the annealing of ZnO in oxygen ambient. We determined that the trap-induced Schottky barrier lowering reduced a drain barrier when the drain was subjected to negative bias stress. Consequentially, the field effect mobility increased from 8.5 m2 V−1·s−1 to 8.9 m2 V−1·s−1 and on-current increased by ~13%.

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ZnO Thin Film Transistors for RF Applications

MRS Proceedings ◽

10.1557/proc-1201-h09-07 ◽

2009 ◽

Vol 1201 ◽

Cited By ~ 1

Author(s):

Burhan Bayraktaroglu ◽

Kevin Leedy ◽

Robert Neidhard

Keyword(s):

Thin Film ◽

Thin Film Transistors ◽

High Performance ◽

Pulsed Laser ◽

Drain Current ◽

Laser Deposition ◽

Current Gain ◽

Zno Thin Film ◽

Rf Applications ◽

Voltage Swing

AbstractNanocrystalline ZnO thin films grown by the pulsed laser deposition technique were used to fabricate high performance thin film transistors suitable for RF applications. It was shown that drain current on/off ratios of higher than 1×1012, sub-threshold voltage swing values lower than 100 mV/decade and hysteresis-free operation could be maintained with films grown across a wide temperature range (25°C to 400°C). Films grown at 200°C have the lowest surface roughness and result in devices with the highest current density operation. Devices with 1.2 μm gate lengths and Au-based gate metals had record current gain and power gain cut off frequencies of fT = 2.9 GHz and fmax = 10 GHz, respectively.

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Effect of Illumination on Organic Polymer Thin-Film Transistors

MRS Proceedings ◽

10.1557/proc-771-l10.17 ◽

2003 ◽

Vol 771 ◽

Cited By ~ 3

Author(s):

Michael C. Hamilton ◽

Sandrine Martin ◽

Jerzy Kanicki

Keyword(s):

Thin Film ◽

Thin Film Transistors ◽

Drain Current ◽

Charge Carriers ◽

Electrical Performance ◽

Organic Polymer ◽

Light Illumination ◽

Polymer Thin Film ◽

Channel Region ◽

White Light Illumination

AbstractWe have investigated the effects of white-light illumination on the electrical performance of organic polymer thin-film transistors (OP-TFTs). The OFF-state drain current is significantly increased, while the drain current in the strong accumulation regime is relatively unaffected. At the same time, the threshold voltage is decreased and the subthreshold slope is increased, while the field-effect mobility of the charge carriers is not affected. The observed effects are explained in terms of the photogeneration of free charge carriers in the channel region due to the absorbed photons.

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Wide range modulation of synaptic weight in thin-film transistors with hafnium oxide gate insulator and indium-zinc oxide channel layer for artificial synapse application

Nanoscale ◽

10.1039/d1nr02911h ◽

2021 ◽

Author(s):

Keonwon Beom ◽

Jimin Han ◽

Hyun-Mi Kim ◽

Tae-Sik Yoon

Keyword(s):

Thin Film ◽

Zinc Oxide ◽

Thin Film Transistors ◽

Hafnium Oxide ◽

Synaptic Weight ◽

Drain Current ◽

Gate Insulator ◽

Channel Layer ◽

Indium Zinc Oxide ◽

Wide Range

Wide range synaptic weight modulation with a tunable drain current was demonstrated in thin-film transistors (TFTs) with a hafnium oxide (HfO2−x) gate insulator and an indium-zinc oxide (IZO) channel layer...

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