Solution-processed ZnO thin-film transistors codoped with Na and F

  • Manoj Kumar
  • Hakyung Jeong
  • Dongjin LeeEmail author


Na and F codoping was utilized to realize high-performance ZnO thin-film transistors derived from sol–gel solution process. The effect of NaF doping concentration on the electrical properties of ZnO thin-film transistors annealed at 350 °C was investigated. Films with 10 at.% doping exhibited excellent performance with an average mobility of 70.98 cm2 V−1 s−1 and a high Ion/Ioff ratio on the order of 106. The X-ray photon spectroscopy exhibited oxygen bound with oxide lattice with and without vacancy related peak position shifted towards lower energy side when doped at 10 at.% and did not show the hydroxyl group on the NaF doped ZnO surface which indicates the improved performance of the thin-film transistors devices. The electrical performance of the devices also changed considerably as the thickness of the NaF-doped ZnO layer increased. Increasing the grain size and realizing a smooth surface morphology by varying the NaF concentration were found to enhance the thin-film transistors mobility.



This work was supported by International Collaborative Research and Development Program funded by the Ministry of Trade, Industry and Energy (MOTIE, Republic of Korea) (N0002626). This work was also supported by the Korea Institute of Energy Technology Evaluation and Planning (KETEP) and the Ministry of Trade, Industry & Energy (MOTIE) of the Republic of Korea (No. 20174010201490). This research was also supported by the 2018 KU Brain Pool of Konkuk University.


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© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.School of Mechanical EngineeringKonkuk UniversitySeoulSouth Korea

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