Journal of IKEEE (전기전자학회논문지)

Institute of Korean Electrical and Electronics Engineers (한국전기전자학회)
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Effect of Channel and Gate Structures on Electrical Characteristics of Oxide Thin-Film Transistors

Channel과 gate 구조에 따른 산화물 박막트랜지스터의 전기적 특성 연구

  • Received : 2022.09.19
  • Accepted : 2022.09.27
  • Published : 2022.09.30
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Abstract

In this study, we designed oxide thin-film transistors (TFTs) with dual gate and tri layered split channels, and investigated the structural effect of the TFTs on the electrical characteristics. The dual gates played a key role in increasing the driving current, and the channel structure of tri layers and split form contributed to the increase in the carrier mobility. The tri layered channels consisting of the a-ITGZO and two ITO layers inserted between the gate dielectric and a-ITGZO led to the increase in the on-current by using ITO layers with high conductivity, and the split channels lowered series resistance of the channels. Compared with the mobility (15 cm2/V·s) of the single gate a-ITGZO TFT, the mobility (134 cm2/V·s) of the dual gate tri-layer split channel TFT was remarkably enhanced by the structural effect.

본 연구에서는 새로운 구조의 dual gate tri-layer split channel 박막트랜지스터를 제작하였다. 전류 구동 능력을 향상시키기 위해 액티브 층의 양쪽에 게이트를 형성하였고 전하이동도를 증가시키기 위하여 액티브 층에서 채널이 형성되는 구간인 첫번째 층과 세번째 층에 전도성이 높은 ITO 층을 배치하였다. 추가적으로 분할 채널을 이용하여 채널의 series 저항을 낮추면서 분할한 채널의 측면에서도 accumulation을 유도하여 전하이동도를 향상시켰다. 기존의 single gate a-ITGZO 박막트랜지스터가 15 cm2/Vs의 전하이동도를 가지는 반면 dual gate tri-layer split channel 박막트랜지스터는 134 cm2/Vs의 높은 전하이동도를 가졌다.

Keywords

Acknowledgement

This study was supported in part by Samsung Display Co. Ltd., and it was supported by a National Research Foundation of Korea (NRF) grant funded by the Korean government (MISP) (NRF-2020R1A2C3004538, NRF-2022M3I7A3046571), the Brain Korea 21 Plus Project of 2022 through the NRF funded by the Ministry of Science and a Korea University Grant.

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