Applied Microscopy

Korean Society of Microscopy (한국현미경학회)
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Effects of Post Annealing on the Electrical Properties of ZnO Thin Films Transistors

  • Moon, Mi Ran (Department of Physics, Institute of Basic Science, and Brain Korea 21 Physics Research Division, Sungkyunkwan University) ;
  • An, Chee-Hong (School of Advanced Materials Science and Engineering, Sungkyunkwan University) ;
  • Na, Sekwon (School of Advanced Materials Science and Engineering, Sungkyunkwan University) ;
  • Jeon, Haseok (School of Advanced Materials Science and Engineering, Sungkyunkwan University) ;
  • Jung, Donggeun (Department of Physics, Institute of Basic Science, and Brain Korea 21 Physics Research Division, Sungkyunkwan University) ;
  • Kim, Hyoungsub (School of Advanced Materials Science and Engineering, Sungkyunkwan University) ;
  • Lee, Hoo-Jeong (School of Advanced Materials Science and Engineering, Sungkyunkwan University)
  • Received : 2012.11.29
  • Accepted : 2012.12.04
  • Published : 2012.12.31
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Abstract

This paper reports the effects of post-annealing of ZnO thin films on their microstructure and the device performance of the transistors fabricated from the films. From X-ray diffraction and transmission electron microscopy characterization, we uncovered that the grain size increased with the annealing temperature escalating and that the film stress shifted from compressive to tensile due to the grain size increment. Electrical characterization revealed that the grain size increase damaged the device performance by drastically lifting the off-current level. By annealing the devices in an $O_2$ ambient (instead of air), we were able to suppress the off-current while improving the electron mobility.

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References

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