Get access

Cross-sectional TEM imaging of β-Ga2O3 thin films formed on c-plane and a-plane sapphire substrates

Authors

  • Shinji Nakagomi,

    Corresponding author
    • Department of Information Technology and Electronics, Faculty of Science and Engineering, Ishinomaki Senshu University, Ishinomaki, Miyagi 986-8580, Japan
    Search for more papers by this author
  • Yoshihiro Kokubun

    1. Department of Information Technology and Electronics, Faculty of Science and Engineering, Ishinomaki Senshu University, Ishinomaki, Miyagi 986-8580, Japan
    Search for more papers by this author

Corresponding author: e-mail nakagomi@isenshu-u.ac.jp, Phone: 81 225 22 7716, Fax: 81 225 22 7746

Abstract

We investigated in detail the microstructure of math formula-oriented β-Ga2O3 thin films on sapphire substrates by transmission electron microscopy (TEM) and electron diffraction. Cross-sectional TEM images of the films on (001) c-plane and (110) a-plane sapphire substrates are composed of four types of regions with different atomic arrangements. The consideration based on the crystal orientation of β-Ga2O3 showed that the type of TEM images corresponds to the projection direction caused by the rotation of the β-Ga2O3 unit cell round the normal to the math formula plane. Electron diffraction patterns corresponding to each region can also be explained in the same manner. These support the results of X-ray pole figure measurements in our previous report. Finally, the relationship among the TEM images, the electron diffraction patterns and the rotation angle of unit cell for math formula-oriented β-Ga2O3 was classified.

Ancillary