Nanomaterials (Apr 2024)

The Enhanced Performance of Oxide Thin-Film Transistors Fabricated by a Two-Step Deposition Pressure Process

  • Mingjie Zhao,
  • Jiahao Yan,
  • Yaotian Wang,
  • Qizhen Chen,
  • Rongjun Cao,
  • Hua Xu,
  • Dong-Sing Wuu,
  • Wan-Yu Wu,
  • Feng-Min Lai,
  • Shui-Yang Lien,
  • Wenzhang Zhu

DOI
https://doi.org/10.3390/nano14080690
Journal volume & issue
Vol. 14, no. 8
p. 690

Abstract

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It is usually difficult to realize high mobility together with a low threshold voltage and good stability for amorphous oxide thin-film transistors (TFTs). In addition, a low fabrication temperature is preferred in terms of enhancing compatibility with the back end of line of the device. In this study, α-IGZO TFTs were prepared by high-power impulse magnetron sputtering (HiPIMS) at room temperature. The channel was prepared under a two-step deposition pressure process to modulate its electrical properties. X-ray photoelectron spectra revealed that the front-channel has a lower Ga content and a higher oxygen vacancy concentration than the back-channel. This process has the advantage of balancing high mobility and a low threshold voltage of the TFT when compared with a conventional homogeneous channel. It also has a simpler fabrication process than that of a dual active layer comprising heterogeneous materials. The HiPIMS process has the advantage of being a low temperature process for oxide TFTs.

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