High-performance a-IGZO TFT with ZrO2 gate dielectric fabricated at room temperature

Since the invention of amorphous indium–gallium–zinc–oxide (IGZO) based thin-film transistors (TFTs) by Hideo Hosono in 2004, investigations on the topic of IGZO TFTs have been rapidly expanded thanks to their high electrical performance, large-area uniformity, and low processing temperature. This article reviews the recent progress and major trends in the field of IGZO-based TFTs. After a brief introduction of the history of IGZO and the main advantages of IGZO-based TFTs, an overview of IGZO materials and IGZO-based TFTs is given. In this part, IGZO material electron travelling orbitals and deposition methods are introduced, and the specific device structures and electrical performance are also presented. Afterwards, the recent advances of IGZO-based TFT applications are summarized, including flat panel display drivers, novel sensors, and emerging neuromorphic systems. In particular, the realization of flexible electronic systems is discussed. The last part of this review consists of the conclusions and gives an outlook over the field with a prediction for the future.

Indium–gallium–zinc–oxide thin-film transistors: Materials, devices, and applications

Metal oxide semiconductors, such as amorphous indium gallium zinc oxide (a-IGZO), have made impressive strides as alternatives to amorphous silicon for electronics applications However, to achieve

Self-Assembled Nanodielectrics for Solution-Processed Top-Gate Amorphous IGZO Thin-Film Transistors.

Low-voltage, high-performance thin film transistors (TFTs) that use amorphous metal oxide (MO) semiconductors as the active layer have been getting tremendous attention due to their essential role in future portable electronic devices and systems. However, reducing the operating voltage of these devices to or below 1 V is a very challenging task because it is very difficult to obtain low threshold voltage ( ${V}_{\text {TH}}$ ) and small subthreshold swing (SS) MO TFTs. In this article, indium gallium zinc oxide (IGZO) TFTs that use solution-deposited Ta2O5 operating at 1 V are demonstrated. To enhance the dielectric properties of the fabricated ultrathin ( ${d} \sim {22}$ nm $\pm ~2$ nm) tantalum pentoxide films, ${n}$ -octadecyltrichlorosilane (OTS) self-assembled monolayer (SAM) was used. The morphology and electrical properties of both pristine and OTS-treated Ta2O5 films have been studied. The optimized Ta2O5/OTS IGZO TFTs operate at 1 V with saturation field-effect mobility larger than 2.3 cm2/ $\text{V}\cdot \text{s}$ , threshold voltage of around 400 mV, SSs below 90 mV/dec, and current ON- OFF ratios well above $10^{{5}}$ . The performance of the presented TFTs is high enough for many commercial applications such as disposable sensors or throwaway, low-end electronics significantly reducing the cost of their production.

Low-Voltage IGZO TFTs Using Solution-Deposited OTS-Modified Ta 2 O 5 Dielectric

Low-temperature fabrication of thin-film dielectrics is essential for various applications including flexible/stretchable electronics, monolithic three-dimensional integrated circuits, and large-ar...

Low-Temperature Fabrication (≤150 °C) of High-Quality Sputtered Silicon Oxide Thin Film with Hydrogen Plasma Treatment

In this letter, self-aligned top-gate (SATG) amorphous In-Ga-Zn-O (a-IGZO) thin-film transistors (TFTs) with an 8.62-nm SiO2 gate dielectric grown by conventional plasma enhanced chemical vapor deposition (PECVD) at 300 °C are fabricated. The results show that the ultrathin PECVD SiO2 film has excellent dielectric properties, such as a low leakage current density of 10−8 A/cm2 at 2 MV/cm, a high breakdown electric field of 9.3 MV/cm, and an almost independent capacitance of bias frequency. The fabricated SATG a-IGZO TFTs with the ultrathin SiO2 gate dielectric exhibit high electrical performances, with major parameters, including a low gate leakage current of 10−13 A, a small subthreshold swing value of 124 mV/decade, a decent field-effect mobility of 10.13 cm2/ $\text{V}\cdot \text{s}$ , and a high ON/OFF current ratio up to 108. Furthermore, the TFTs also show a good electrical stability under positive and negative gate bias stresses.

Self-Aligned Top-Gate Amorphous InGaZnO TFTs With Plasma Enhanced Chemical Vapor Deposited Sub-10 nm SiO 2 Gate Dielectric for Low-Voltage Applications

P‐1.5: Fabrication of Self‐Aligned Top‐Gate Amorphous InGaZnO Thin‐Film Transistors with Submicron Channel Length

Performances of self-aligned top-gate (SATG) amorphous In-Ga-Zn-O (a-IGZO) thin-film transistors (TFTs) with ultrathin SiO 2 gate dielectric grown by conventional plasma enhanced chemical vapor deposition (PECVD) are investigated Results show that the fabricated a-IGZO TFTs could present a high performance even if the PECVD gate SiO 2 is thinned to 10 nm scale

Yunkai Cao

Papers

Self-Aligned Top-Gate Amorphous InGaZnO TFTs With Plasma Enhanced Chemical Vapor Deposited Sub-10 nm SiO 2 Gate Dielectric for Low-Voltage Applications

P‐1.5: Fabrication of Self‐Aligned Top‐Gate Amorphous InGaZnO Thin‐Film Transistors with Submicron Channel Length

Performances of Self-Aligned Top-Gate a-IGZO TFTs with Ultrathin PECVD SiO 2 Gate Dielectric