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	High-quality InGaN epilayers grown by PA-MBE and abnormal incorporation behavior of Indium into InGaN 期刊论文 OAI收割 ACTA PHYSICA SINICA, 2013, 卷号: 62, 期号: 8 作者: Yang, H(杨辉); Wang, JF(王建峰) 收藏 \| 浏览/下载：23/0 \| 提交时间：2014/01/13 InGaN epilayer plasma-assisted molecular beam epitaxy indium incorporation crystalline quality
	Control of N/N2 species ratio in NO plasma for p-type doping of ZnO (EI CONFERENCE) 会议论文 OAI收割作者: Chen X.; Liu L.; Liu L.; Li B.; Li B. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 Nitrogen-doped ZnO thin films were grown on c-plane sapphire (Al 2O3) substrates via plasma-assisted molecular beam epitaxy using plasma activated nitric oxide (NO) as the oxygen source and dopant. X-ray diffraction measurements indicate that a small NO flux benefits the crystal quality of the thin films. Hall effect measurements indicate that the electron density of the ZnO films decreases gradually with decreasing NO flux and the conduction reverses to p-type at a certain flux. Optical emission spectra indicate that the N atom content in the NO plasma increases with decreasing NO flux and the origin of this is discussed. X-ray photoelectron spectroscopy measurements demonstrate that the number of N atom occupied O sites in the ZnO lattice increases correspondingly. 2011 American Institute of Physics.
	Effect of interface on luminescence properties in ZnO/MgZnO heterostructures (EI CONFERENCE) 会议论文 OAI收割 Wei Z. P.; Lu Y. M.; Shen D. Z.; Wu C. X.; Zhang Z. Z.; Zhao D. X.; Zhang J. Y.; Fan X. W. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 A set of ZnO/MgZnO heterostructures with well widths Lw varying from 2 to 20 nm has been grown by plasma-assisted molecular-beam epitaxy (P-MBE). We present a room-temperature (RT) study of the well-width-dependent photoluminescence (PL) spectra and carrier lifetimes in ZnO/MgZnO heterostructures. Bi-exponential process is seen at RT time-decay curves of the luminescence from the well layers. The fast process is from the recombination of the free exciton while the slow process is attributing to the recombination of the localized exciton in the interface of ZnO and MgZnO. It is also confirmed from the PL peak shift of time-resolved PL spectra. With decreasing the well thickness the fast process gradually increases and dominantly contributes to the PL spectrum due to the interface improvement. 2006 Elsevier B.V. All rights reserved.
	Excitonic properties of vertically aligned ZnO nanotubes under high-density excitation (EI CONFERENCE) 会议论文 OAI收割 Lu Y. M.; Liang H. W.; Shen D. Z.; Zhang Z. Z.; Zhang J. Y.; Zhao D. X.; Liu Y. C.; Fan X. W. 收藏 \| 浏览/下载：13/0 \| 提交时间：2013/03/25 In this paper highly oriented and vertically arranged ZnO nanotubes are prepared on Al2O3 (0 0 0 1) substrate without employing any metal catalysts by plasma-assisted molecular beam epitaxy. The photoluminescence (PL) spectra at room temperature are studied under high excitation densities. Under lower excitation density (60 kW/cm2) PL spectrum shows that one strong free exciton emission (FE) locates at 3.306 eV. As the excitation density increases up to 200 kW/cm2 a new emission peak (Pn) located at low-energy side of FE is attributed to the spontaneous emission due to an exciton-exciton (Ex-E x) scattering process from two ground state excitons where one exciton is recombined by emitting a photon and the other is scattered into the excited states of n=2 3 4.... Under excitation density of 300 kW/cm 2 the stimulated emission originating from Ex-E x scattering is obtained. When the excitation density is above 580 kW/cm2 the emission from electron-hole plasma is observed in low-energy side of the P band and indicates a typical superradiation recombination processes with increasing excitation density. 2006 Elsevier B.V. All rights reserved.
	Raman spectra and phonon modes of MgxZn1-xO alloy films (EI CONFERENCE) 会议论文 OAI收割 12th International Conference on II-VI Compounds, September 12, 2005 - September 16, 2005, Warsaw, Poland Wei Z. P.; Lu Y. M.; Shen D. Z.; Zhang Z. Z.; Wu C. X.; Zhang J. Y.; Yao B.; Fan X. W. 收藏 \| 浏览/下载：23/0 \| 提交时间：2013/03/25 Hexagonal MgxZn1-xO alloy layers with 0 &le 0.3 have been grown by plasma-assisted molecular beam epitaxy on sapphire (006) and Si (111) substrates. Their crystal structures are characterized by x-ray diffraction spectroscopy. The nonresonant and resonant Raman spectra were measured using 488 nm line from Ar+ laser and 325 nm line from He-Cd laser by backscattering geometry. Four Raman modes (E2 high LO TO multiphonon processes) were observed in the nonresonant Raman spectra of hexagonal MgxZn1-xO with different Mg contents. The optical phonon frequencies were found to display one-mode behaviour for all the samples since no separate ZnO- and MgO-like modes were observed. The long-wavelength frequencies of ZnO-like optical phonons measured in the resonant Raman spectra can be expressed as linear functions of x. These behaviours can be explained within a modified random-element-isodisplacement model (MREI). 2006 WILEY-VCH Verlag GmbH Co. KGaA.
	Ultraviolet electroluminescence of ZnO based heterojunction light emitting diode (EI CONFERENCE) 会议论文 OAI收割 12th International Conference on II-VI Compounds, September 12, 2005 - September 16, 2005, Warsaw, Poland Jiao S. J.; Lu Y. M.; Shen D. Z.; Zhang Z. Z.; Li B. H.; Zhang J. Y.; Yao B.; Liu Y. C.; Fan X. W. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 ZnO/GaN p-i-n heterojunctions light emitting diodes were fabricated by plasma-assisted molecular beam epitaxy. We make use of high resistivity of nitrogen doped ZnO to fabricate n-ZnO/i-ZnO/p-GaN heterojunction light emitting diode. The emission of i-ZnO was obtained due to the limitation effect of i-ZnO on electrons and holes. Moreover n-ZnO/i-MgO/p-GaN heterojunction light emitting diode was also fabricated. The limitation effect on electrons is increased in this heterojunction. The bright ultraviolet electroluminescence at 382 nm originating from the ZnO layer was observed in the room temperature electroluminescence spectrum. We hope to realize the stimulated emission of ZnO using these heterojunctions by the improvement of crystal quality and the optimization of device structure. 2006 WILEY-VCH Verlag GmbH Co. KGaA.
	Characterization of ZnO/Mg0.12Zn0.88O heterostructure grown by plasma-assisted molecular beam epitaxy (EI CONFERENCE) 会议论文 OAI收割 13th International Conference on Molecular Beam Epitaxy, August 22, 2004 - August 27, 2004, 13th International Conference on Molecular Beam Epitaxy, August 22, 2004 - August 27, 2004 Lu Y. M.; Wu C. X.; Wei Z. P.; Zhang Z. Z.; Zhao D. X.; Zhang J. Y.; Liu Y. C.; Shen D. Z.; Fan X. W. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 In this paper Mg0.12Zn0.88O/ZnO heterostructures were fabricated on c-plane sapphire (Al2O3) substrates by plasma-assisted molecular beam epitaxy (P-MBE). The quality of the Mg 0.12Zn0.88O alloy thin film was characterized by X-ray diffraction (XRD) and reflection high-energy electron diffraction (RHEED). Optical properties of the Mg0.12Zn0.88O/ZnO heterostructure were studied by absorption and photoluminescence (PL) spectra. At room temperature (RT) Mg0.12Zn0.88O/ZnO heterostructures show two absorption edges originating from ZnO and Mg 0.12Zn0.88O layers respectively. In PL spectra two ultraviolet emission bands related to the ZnO layer and the Mg 0.12Zn0.88O layer were observed. The emission band from Mg0.12Zn0.88O layer dominates at moderately lower temperature and the luminescence of ZnO becomes gradually important with increasing temperature. This is suggested to exist as a potential barrier in the interface and to restrict the relaxation of the carriers from the Mg 0.12Zn0.88O layer to ZnO layer. As the thickness of ZnO layer decreases the emission from the Mg0.12Zn0.88O layer becomes weaker and weaker. When the ZnO thickness is up to 2 nm only the luminescence of the ZnO layer is observed at RT. The quenching of the emission corresponding to the MgZnO layer indicates the existence of a strong injection process in the samples with thinner ZnO layer. 2005 Elsevier B.V. All rights reserved.