전기전자학회논문지 (Journal of IKEEE)

  • 제25권3호
  • /
  • Pages.501-505
  • /
  • 2021
  • /
  • 1226-7244(pISSN)
  • /
  • 2288-243X(eISSN)
한국전기전자학회 (Institute of Korean Electrical and Electronics Engineers)
권호 표지
DOI QR코드

DOI QR Code

게이트 절연막 조성에 따른 a-ITGZO 박막트랜지스터의 전기적 특성 연구

Effect of Gate Dielectrics on Electrical Characteristics of a-ITGZO Thin-Film Transistors

  • Kong, Heesung (Dept. of Electrical Engineering, Korea University) ;
  • Cho, Kyoungah (Dept. of Electrical Engineering, Korea University) ;
  • Kim, Sangsig (Dept. of Electrical Engineering, Korea University)
  • 투고 : 2021.08.20
  • 심사 : 2021.09.29
  • 발행 : 2021.09.30
PDF 다운로드
⟨ 이전 논문 다음 논문 ⟩

초록

본 연구에서는 HfO2와 Al2O3 비율을 조절하여 게이트 절연막을 구성하고, 게이트 절연막에 따른 a-ITGZO 박막트랜지스터의 전기적 특성을 분석하였다. HfO2 게이트 절연막, HfO2와 Al2O3 비율이 2:1인 게이트 절연막, HfO2와 Al2O3 비율이 1:1인 게이트 절연막으로 구성된 a-ITGZO 박막트랜지스터의 전자이동도는 각각 32.3, 26.4, 16.8 cm2/Vs이고 SS 값은 각각 206, 160, 173 mV/dec 이며 히스테리시스 윈도우 폭은 각각 0.60, 0.12, 0.09 V 이었다. 게이트 절연막에서 Al2O3 비율이 높아질수록 a-ITGZO 박막트랜지스터의 히스테리시스 윈도우 폭이 감소했는데, 이는 Al2O3 비율이 높아질수록 게이트 절연막과 채널 박막 사이의 interface trap density가 감소했기 때문이다.

In this study, we fabricated amorphous indium-tin-gallium-zinc-oxide thin-film transistors (a-ITGZO TFTs) with gate dielectrics of HfO2 and the mixed layers of HfO2 and Al2O3, and investigated the effect of gate dielectric on electrical characteristics of a-ITGZO TFTs. When only HfO2 was used as the gate dielectric, the mobility and subthreshold swing (SS) were 32.3 cm2/Vs and 206 mV/dec. For the a-ITGZO TFTs with gate dielectric made of HfO2 and Al2O (2:1, 1:1), the mobilities and SS were 26.4 cm2/Vs (2:1), 16.8 cm2/Vs(1:1), 160 mV/dec (2:1) and 173 mV/dec (1:1). On the other hand, the hysteresis window shown in transfer curves of the a-ITGZO TFTs was lessened from 0.60 to 0.09 V by the increase of Al2O3 ratio in gate dielectric, indicating that the interface trap density between the gate dielectric and channel layer decreases due to Al2O3.

키워드

과제정보

This study was supported in part by Samsung Display Co. Ltd., the Brain Korea 21 Plus Project, 2021, and Korea University Grant.

참고문헌

  1. I. Choi, M. Kim, N. On, A. Song, K. Chung, H. Jeong, J. Park and J. Jeong, "Achieving High Moility and Excellent Stability in Amorphous In-Ga-Zn-Sn-O Thin Film Transistors," IEEE Trans. Electron Devices vol.67, pp.1014-1020, 2020. DOI: 10.1109/TED.2020.2968592
  2. H. Lee, K. Cho and S. Kim, "Electrical characteristics of bendable a-ITGZO TFTs on colorless polyimide substrates," Semicond. Sci. Technol. vol.35, pp.065014, 2020. DOI: 10.1088/1361-6641/ab8439
  3. D. Kim, K. Cho, S. Woo and S. Kim, "Electrical characteristics of amorphous indium-tin-gallium-zinc oxide TFTs under positive gate bias stress," Electron. Lett. vol. 56, pp.102-104, 2020. DOI: 10.1049/el.2019.2784
  4. P. Ma, J. Sun, G. Zhang, G. Liang, Q. Xin, Y. Li and A. Song, "Low-temperature fabrication of HfAlO alloy dielectric using atomic-layer deposition and its application in a low-power device," Journal of Alloys and Compounds vol.792, pp.543-549, 2019. DOI: 10.1016/j.jallcom.2019.04.015
  5. Y. Ding, and D. Misra, "Oxide structure-dependent interfacial layer defects of HfAlO/SiO2/Si stack analyzed by conductance method," J. Vac. Sci. Technol. B, vol.33, 021203, 2015. DOI: 10.1116/1.4913280
  6. B. Lu, H. Lv, Y. Zhang and C. Liu, "Composition of HfAlO, HfO2/Al2O3, and HfO2 on n-type GaAs using atomic layer deposition," Superlattices and Microstructures vol.99, pp.54-57, 2016. DOI: 10.1016/j.spmi.2016.07.032
  7. C. Mahata, Y. Byun, C. An, S. Choi, Y. An and H. Kim, "Comparative Study of Atomic-LayerDeposited Stacked (HfO2/Al2O3) and Nanolaminated (HfAlOx) Dielectrics on In0.53Ga0.47As," ACS Appl. Mater. Interfaces vol.5, pp.4195-4201, 2013. DOI: 10.1021/am400368x
  8. D. Won, H. Kim, M. Nguyen, J. Myoung, R. Choi and H. Yoon, "Residual Image Suppression Through Annealing Process of Amorphous Indium Gallium Zinc Oxide Thin Film Transistor for Plastic Organic Light-Emitting Diode Display," J. Nanosci. Nanotechnol. vol.20, pp.6877-6883, 2020. DOI: 10.1166/jnn.2020.18807
  9. Z. Ye, Y. Yuan, H. Xu, Y. Liu, J. Luo, W, M. Wong, "Mechanism and Origin of Hysteresis in Oxide Thin-Film Transistor and Its Application on 3-D Nonvolatile Memory," IEEE Trans. Electron Devices vol.64, pp.438-446, 2017. DOI: 10.1109/ted.2016.2641476