In-plane polarities of nonpolar wurtzite epitaxial films deposited on m- and r-plane sapphire substrates

Philippe Vennéguès (1) , Tiankai Zhu , Z. Bougrioua (2) , Denis Martin , J. Zuniga-Perez (1) , Nicolas Grandjean

1 CRHEA - Centre de recherche sur l'hétéroepitaxie et ses applications
2 IEMN - Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520

The in-plane polarities of GaN and ZnO non-polar films deposited on r - and m-sapphire are compared. The polarity is unique on r-sapphire and mixed on m-sapphire because the direction on the substrate surface parallel to the wurztite c-direction is polar in the first case and nonpolar in the second case. Furthermore, on r-sapphire where GaN and ZnO have a unique polarity, the directions of the polar c-axis relative to a reference sense in the substrate surface are opposite for both materials. This difference may be related to the nitridation which is the first step of the of III-nitride growth.

Domaines: Sciences de l'ingénieur [physics]

Philippe Vennéguès, Tiankai Zhu, Z. Bougrioua, Denis Martin, J. Zuniga-Perez, et al.. In-plane polarities of nonpolar wurtzite epitaxial films deposited on m- and r-plane sapphire substrates. Japanese Journal of Applied Physics, part 1 : Regular papers, Short Notes, 2009, 48 (9), pp.090211-1-3. ⟨10.1143/JJAP.48.090211⟩. ⟨hal-00472455⟩