High-Mobility Inkjet-Printed Indium-Gallium-Zinc-Oxide Thin-Film Transistors Using Sr-Doped Al₂O₃ Gate Dielectric.

Seungbeom Choi,Yong-Hoon Kim,Sung Park,Kyung-Tae Kim

doi:10.3390/ma12060852

Seungbeom Choi, Yong-Hoon Kim + Show 2 more

Open Access

https://doi.org/10.3390/ma12060852

Copy DOI

Journal: Materials	Publication Date: Mar 13, 2019
Citations: 14	License type: CC BY 4.0

Affiliation: Sungkyunkwan University, Chung-Ang University

Abstract

In this paper, we demonstrate high-mobility inkjet-printed indium-gallium-zinc-oxide (IGZO) thin-film transistors (TFTs) using a solution-processed Sr-doped Al2O3 (SAO) gate dielectric. Particularly, to enhance to the electrical properties of inkjet-printed IGZO TFTs, a linear-type printing pattern was adopted for printing the IGZO channel layer. Compared to dot array printing patterns (4 × 4 and 5 × 5 dot arrays), the linear-type pattern resulted in the formation of a relatively thin and uniform IGZO channel layer. Also, to improve the subthreshold characteristics and low-voltage operation of the device, a high-k and thin (~10 nm) SAO film was used as the gate dielectric layer. Compared to the devices with SiO2 gate dielectric, the inkjet-printed IGZO TFTs with SAO gate dielectric exhibited substantially high field-effect mobility (30.7 cm2/Vs). Moreover, the subthreshold slope and total trap density of states were also significantly reduced to 0.14 V/decade and 8.4 × 1011/cm2·eV, respectively.

Highlights

Amorphous oxide semiconductor (AOS)-based thin-film transistors (TFTs) have received a considerable interest in the fields of displays, sensors, and wearable electronics owing to their high carrier mobility, good operational stability and flexibility, and large-area scalability [1,2,3,4,5]
In the fabrication of AOS-based TFTs, the AOS channel layer should be patterned in order to isolate each TFT device and reduce the leakage between the devices
Dot array, the drop spacing between each drop was μm in of the channel layer especially at the center region was very thin and the device vertical showed relatively and lateral directions

Summary

Introduction

Amorphous oxide semiconductor (AOS)-based thin-film transistors (TFTs) have received a considerable interest in the fields of displays, sensors, and wearable electronics owing to their high carrier mobility, good operational stability and flexibility, and large-area scalability [1,2,3,4,5]. A self-patterning method which utilizes the surface energy difference can be used to pattern the AOS channel layer without using the photolithography process [10,11,12], this may require wet chemical processes to obtain the surface energy contrast. Direct printing methods such as inkjet printing, on the other hand, allow a simple and efficient way to pattern the AOS channel layer, by directly forming the channel layer on the substrate

Methods

Results

Conclusion