Figure 2.

SEM images. ZnO films deposited on different substrates: (a) Si substrate and (c) GaN/Si substrate. (b) Annealed GaN thin films deposited on Si substrate at 800°C. (d) The cross-sectional images of the ZnO nanostructure on GaN/Si (111) substrates. (e) EDX spectrum of ZnO nanostructure derived from (c).