Bias-stress stability of top-gate coplanar a-ITGZO TFTs with HfO2 and HfAlO gate dielectrics

Heesung Kong, Kyoungah Cho, Hosang Lee, Seungjun Lee, Junhyung Lim, Sangsig Kim

Research output: Contribution to journalArticlepeer-review

5 Citations (Scopus)


In this study, we investigated the electrical characteristics of amorphous indium–tin–gallium–zinc-oxide thin-film transistors (TFTs) (a-ITGZO TFTs) with HfO2 and HfAlO gate dielectrics. The mobilities of the a-ITGZO TFTs with HfO2 and HfAlO were 32.3 and 26.4 cm2/V &·s, respectively. The TFT with HfO2 showed a subthreshold swing (SS) of 206 mV/dec and a hysteresis window of 0.60 V, and the TFT with HfAlO showed an SS of 160 mV/dec and a hysteresis window of 0.12 V. The hysteresis windows were related to the interface trap density. The TFT with HfO2 was more vulnerable to positive bias stress; in contrast, the TFT with HfAlO operated stably even after it experienced positive and negative bias stresses for 3000 s.

Original languageEnglish
Article number106527
JournalMaterials Science in Semiconductor Processing
Publication statusPublished - 2022 Jun 1

Bibliographical note

Funding Information:
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 (MSIT) ( 2020R1A2C3004538 ), the Technology Development Program to Solve Climate Change ( NRF-2017M1A2A2087323 ), the Brain Korea 21 Plus Project of 2021 through the NRF funded by the Ministry of Science, ICT & Future Planning , and the Korea University Grant.

Publisher Copyright:
© 2022 Elsevier Ltd


  • Amorphous indium–tin–gallium–zinc-oxide
  • Hafnium aluminum oxide
  • Hafnium oxide
  • Hysteresis
  • Negative gate-bias stress
  • Positive gate-bias stress

ASJC Scopus subject areas

  • General Materials Science
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering


Dive into the research topics of 'Bias-stress stability of top-gate coplanar a-ITGZO TFTs with HfO2 and HfAlO gate dielectrics'. Together they form a unique fingerprint.

Cite this