Next Article in Journal
Coordination Assemblies of Zn(II) Coordination Polymers: Positional Isomeric Effect and Optical Properties
Next Article in Special Issue
Dislocation Analysis in SiGe Heterostructures by Large-Angle Convergent Beam Electron Diffraction
Previous Article in Journal
Symmetric Fluoroborate and its Boron Modification: Crystal and Electronic Structures
Previous Article in Special Issue
Origin of Nanoscale Incipient Plasticity in GaAs and InP Crystal
Open AccessArticle

Comparative Study of ZnO Nanostructures Grown on Variously Orientated GaN and AlxGa1−xN: The Role of Polarization, and Surface Pits

1
Key Laboratory of Opto-electronics Technology, Microelectronic School, Beijing University of Technology, Beijing 100124, China
2
Institute of Microelectronics of Chinese Academy of Science, Beijing 100029, China
*
Author to whom correspondence should be addressed.
Crystals 2019, 9(12), 663; https://doi.org/10.3390/cryst9120663
Received: 29 September 2019 / Revised: 3 December 2019 / Accepted: 3 December 2019 / Published: 9 December 2019
(This article belongs to the Special Issue Dislocations in Heterostructures)
Through comparing ZnO directly grown on the substrates of a-plane, c-plane, and (11-22) plane GaN and AlxGa1−xN (0.06 ≤ x ≤ 1), the roles of different factors that may influence growth have been studied. Seeded by surface pits, ZnO nanowire (NW) preferentially grew along the polarized direction on top of the nonpolar GaN (laterally aligned), polar GaN and AlGaN (vertically aligned), and semipolar GaN (obliquely upward aligned). Nanosheets were easily formed when the polarized surface of the AlGaN film was not intact. The kinetic effect of polarization must be considered to explain the high aspect ratio of NWs along the polarized direction. It was found that dislocation affected NW growth through the surface pits, which provided excellent nucleation sites. If the surface pits on GaN could be controlled to distribute uniformly, self-organized ZnO NW array could be controllably and directly grown on GaN. Moreover, surface pits could also seed for nanosheet growth in AlN, since Al(OH)4 would presumably bind to the Zn2+ terminated surface and suppress the kinetic effects of polarization. View Full-Text
Keywords: a-plane GaN; c-plane GaN; semipolar GaN; AlxGa1−xN; surface pits; polarization; dislocation a-plane GaN; c-plane GaN; semipolar GaN; AlxGa1−xN; surface pits; polarization; dislocation
Show Figures

Figure 1

MDPI and ACS Style

Gao, Z.; Lu, L.; Xue, X.; Li, J.; Zhao, L.; Ahmad, D.; Li, H. Comparative Study of ZnO Nanostructures Grown on Variously Orientated GaN and AlxGa1−xN: The Role of Polarization, and Surface Pits. Crystals 2019, 9, 663.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop