TITLE

Control of polarity of ZnO films grown by plasma-assisted molecular-beam epitaxy: Zn- and O-polar ZnO films on Ga-polar GaN templates

AUTHOR(S)
Hong, Soon-Ku; Soon-Ku Hong; Hanada, Takashi; Ko, Hang-Ju; Hang-Ju Ko; Chen, Yefan; Yefan Chen; Yao, Takafumi; Imai, Daisuke; Araki, Kiyoaki; Shinohara, Makoto
PUB. DATE
November 2000
SOURCE
Applied Physics Letters;11/27/2000, Vol. 77 Issue 22
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
We report on the growth of polarity-controlled ZnO films by plasma-assisted molecular-beam epitaxy. Different polar (Zn- and O-polar) ZnO films on unipolar (Ga-polar) GaN epilayers are selectively grown. Polarity of ZnO films is evaluated by coaxial impact collision ion scattering spectroscopy. Zn preexposure prior to ZnO growth results in Zn-polar ZnO films (Zn face), while O-plasma preexposure leads to the growth of O-polar ZnO films (O face). High-resolution transmission electron microscopy reveals the formation of an interface layer between ZnO and GaN epilayers in O-plasma preexposed samples, while no interface layer is observed in Zn preexposed samples. The interface layer is identified as single crystalline, monoclinic Ga[sub 2]O[sub 3]. We propose models for interface configurations at ZnO/GaN heterointerfaces, which can successfully explain the different polarities of the ZnO films. © 2000 American Institute of Physics.
ACCESSION #
4415077

 

Related Articles

  • Plasma-assisted molecular-beam epitaxy of ZnO epilayers on atomically flat MgAl[sub 2]O[sub 4](111) substrates. Chen, Yefan; Hong, Soon-ku; Ko, Hang-ju; Nakajima, Masa; Yao, Takafumi; Segawa, Yusaburo // Applied Physics Letters;1/10/2000, Vol. 76 Issue 2, p245 

    Plasma-assisted molecular-beam epitaxy of ZnO epilayers on MgAl[sub 2]O[sub 4](111) substrates is described. Acid mixed by H[sub 2]SO[sub 4] and H[sub 3]PO[sub 4] was used for the substrate etching, which provides atomically flat surfaces with a regular terrace array. The influence of the...

  • Characterization of homoepitaxial p-type ZnO grown by molecular beam epitaxy. Look, D. C.; Reynolds, D. C.; Litton, C. W.; Jones, R. L.; Eason, D. B.; Cantwell, G. // Applied Physics Letters;9/2/2002, Vol. 81 Issue 10, p1830 

    An N-doped, p-type ZnO layer has been grown by molecular beam epitaxy on an Li-diffused, bulk, semi-insulating ZnO substrate. Hall-effect and conductivity measurements on the layer give: resistivity = 4 × 10¹ Ω cm; hole mobility = 2 cm²/Vs; and hole concentration = 9 × 10[sup...

  • Uniaxial locked epitaxy of ZnO on the a face of sapphire. Fons, P.; Iwata, K.; Yamada, A.; Matsubara, K.; Niki, S.; Nakahara, K.; Tanabe, T.; Takasu, H. // Applied Physics Letters;9/18/2000, Vol. 77 Issue 12 

    High-quality, c-oriented ZnO epitaxial films have been grown on the a surface using molecular-beam epitaxy. The use of a-oriented sapphire eliminates rotational domains and related structural defects which have limited the use of ZnO in electronic applications. The ZnO epitaxial layers are...

  • Properties of the shallow O-related acceptor level in ZnSe. Chen, J.; Zhang, Y.; Skromme, B. J.; Akimoto, K.; Pachuta, S. J. // Journal of Applied Physics;10/15/1995, Vol. 78 Issue 8, p5109 

    Presents information on a study which investigated the properties of the shallow oxygen-related acceptor level in zinc oxide-doped molecular beam epitaxy material. Methods; Results; Discussion.

  • Optically pumped lasing of ZnO at room temperature. Bagnall, D.M.; Chen, Y.F.; Zhu, Z.; Yao, T.; Koyama, S.; Shen, M.Y.; Goto, T. // Applied Physics Letters;4/28/1997, Vol. 70 Issue 17, p2230 

    Examines the growth of zinc oxide (ZnO) thin films by microwave plasma-enhanced molecular beam epitaxy on (0001) sapphire substrates. Threshold excitation intensity of optically pumped lasing of ZnO in cleaved laser cavities; Quality of the epilayers; Viability of ZnO-based light emitting devices.

  • Morphology evolution of ZnO(000 1‾) surface during plasma-assisted molecular-beam epitaxy. Yefan Chen; Hang-Ju Ko; Yao, Takafumi; Segawa, Yusaburo // Applied Physics Letters;2/25/2002, Vol. 80 Issue 8, p1358 

    Examines the morphology evolution of ZnO(000 1) surface during plasma-assisted molecular-beam epitaxy. Surface of the zinc oxide epilayers; Sensitivity of the surface morphology to the Zinc/Oxygen ratio; Stabilization of mobile zinc adatoms by oxygen.

  • Site-specific growth of Zno nanorods using catalysis-driven molecular-beam epitaxy. Heo, Y. W.; Varadarajan, V.; Kaufman, M.; Kim, K.; Norton, D. P.; Ren, F.; Fleming, P. H. // Applied Physics Letters;10/14/2002, Vol. 81 Issue 16, p3046 

    We report on catalyst-driven molecular beam epitaxy of ZnO nanorods. The process is site specific, as single crystal ZnO nanorod growth is realized via nucleation on Ag films or islands that are deposited on a SiO[sub 2]-terminated Si substrate surface. Growth occurs at substrate temperatures on...

  • Investigation of ZnO epilayers grown under various Zn/O ratios by plasma-assisted molecular-beam epitaxy. Ko, Hang-Ju; Yao, Takafumi; Chen, Yefan; Hong, Soon-Ku // Journal of Applied Physics;10/15/2002, Vol. 92 Issue 8, p4354 

    We have investigated ZnO epilayers grown under various Zn/O ratios by plasma-assisted molecular-beam epitaxy. The growth conditions are elucidated by a relationship between growth rate and Zn/O ratios. Surface phase diagrams are obtained by investigation of reflection high-energy electron...

  • Band alignment at a ZnO/GaN (0001) heterointerface. Hong, Soon-Ku; Hanada, Takashi; Makino, Hisao; Chen, Yefan; Ko, Hang-Ju; Yao, Takafumi; Tanaka, Akinori; Sasaki, Hiroyuki; Sato, Shigeru // Applied Physics Letters;5/21/2001, Vol. 78 Issue 21, p3349 

    We report the experimental results of the valence band offset at a ZnO/GaN (0001) heterointerface. The ZnO/GaN (0001) heterointerface is prepared by growing a ZnO layer on (0001) GaN/Al[sub 2]O[sub 3], in which the ZnO layer is epitaxially deposited by plasma-assisted molecular-beam epitaxy,...

Share

Read the Article

Courtesy of VIRGINIA BEACH PUBLIC LIBRARY AND SYSTEM

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics