Journal of Materials Science: Materials in Electronics

, Volume 29, Issue 17, pp 14620–14634 | Cite as

Microstructure evolution and grain orientation in ITO targets and their effects on the film characteristics

  • Fangsheng Mei
  • Tiechui YuanEmail author
  • Ruidi LiEmail author
  • Kai Qin
  • Jingwei Huang


ITO targets sintered at 1560–1600 °C were selected to deposit ITO films at 25 and 150 °C with a purpose of investigating the relationship between microstructure evolution and grain orientation in ITO targets and the film characteristics. It is found that, with increasing the sintering temperature, the triangle grains of In4Sn3O12 (secondary phase) transform into the dendritic grains of In2SnO5 (secondary phase), following by the increase of the solid solubility of tin oxide in In2O3 phase (main phase). Besides, the sintering temperature has a great influence only on the texture of secondary phase. More solid solubility of tin oxide in In2O3 phase, stronger texture intensity of secondary phase and higher sputtering temperature were found to promote the crystallinity of ITO films resulting in the lower sheet resistance and obtain the films with lower compression stress and strong adhesion. The transmittance of ITO films deposited at 25 °C is closely related to the film surface roughness, while it is mainly associated with the crystal structure for ITO films deposited at 150 °C.



This study was supported by Zhuzhou Smelter Group Co., LTD., Hunan, China.


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

Authors and Affiliations

  1. 1.Science and Technology on High Strength Structural Materials LaboratoryCentral South UniversityChangshaPeople’s Republic of China
  2. 2.State Key Laboratory of Powder MetallurgyCentral South UniversityChangshaPeople’s Republic of China

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