STUDY OF EXCITONIC PROPETIES OF LOW-DIMENSINAL ZnO

低维ZnO激子性质的研究

• 批准号: 10650024
• 负责人: YASUDA Takashi
• 金额: $ 0.64万
• 依托单位: Ishinomaki Senshu University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10650024/
• 关键词: ZnO; MgZnO; Quantum Well; Photoluminescence; Exciton; Ultla-Violet Laser; Oxide

High quality epitaxial layers of ZnO were successfully grown by laser MBE, which attracts much attention for new ultra-violet semiconductor lasers. For the fabrications of laser structures, development of cladding materials with larger bandgap than ZnO is important in this material system. Incorporation of Mg into ZnO up to 20% was successfully achieved using laser MBE, resulting in the increase of bandgap. Multi-quantum wells (MQWs) structures of ZnO/MgZnO were grown on sapphire substrates to observe the carrier confinement effects. The periodic structures with the order of lOnm in sizes were confirmed by a x-ray diffraction measurement as well as a transmission electron microscope observation. The minimum well width achieved in this study was about 1 nm. Low temperature photoluminescence(PL) and photoluminescence excitation(PLE) were performed to investigate the quantized electronic states in these structures. Blue shift of PL emission peaks as well as PLE absorption peaks were observed by decreasing the well width, which is in good agreement with the calculations based on quantum well structures. The large stokes shift between PL and PLE peaks exhibits that the localized excitons play an important role in these NIQWs, which was also confirmed from the result of temperature dependence of PL measurement.

激光MBE成功地生长了ZnO的高质量外延层，这引起了人们对新的紫外线激光器的广泛关注。对于激光结构的制造，在该材料系统中，具有比ZnO更大带隙的覆层材料的开发很重要。使用激光MBE成功实现了MG中最高20％的ZnO，从而导致带隙的增加。在蓝宝石底物上生长了ZnO/mgzno的多量子井（MQWS）结构，以观察载体约束效应。通过X射线衍射测量以及透射电子显微镜观察确认了具有LONM大小的lonm级的周期结构。这项研究中达到的最低井宽度约为1 nm。进行低温光致发光（PL）和光致发光激发（PLE），以研究这些结构中的量化电子状态。通过降低井宽度，可以观察到PL发射峰的蓝移以及PLE吸收峰，这与基于量子井结构的计算非常吻合。 PL和PLE峰之间的大型Stokes移动表明，局部激子在这些NIQW中起着重要作用，这也从PL测量的温度依赖性的结果中得到了证实。

项目成果

A.Ohtomo, M. Kawasaki, I.Ohkubo, H.Koinuma, T.Yasuda and Y.Segawa: "Structure and optical properties of ZnO/MgィイD20.2ィエD2ZnィイD20.8ィエD2O superlattices"Appl.Phys.. 75. 980-982 (1999)

A.Ohtomo、M. Kawasaki、I.Ohkubo、H.Koinuma、T.Yasuda 和 Y.Sekawa：“ZnO/MgD20.2D20.8D2O 超晶格的结构和光学性质”Appl.Phys.. 75. 980-982 ( 1999）

A. Ohtomo: "Fabrication of alloys and superlatives based on ZnO towards ultraviolet laser"Materials Science and Engineering. 1356. 263-266 (1998)

A. Ohtomo：“基于 ZnO 的紫外激光合金和最高级材料的制造”材料科学与工程。

A. Ohtomo: "Double Heterostructure Based on ZnO and Mg_XMgZn_<1-X>O"Materials Science Forum. 264-268. 1463-1466 (1998)

A. Ohtomo：“基于ZnO和Mg_XMgZn_<1-X>O的双异质结构”材料科学论坛。

A. Ohtomo: "Mg_XMgZn_<1-X>O as a II-VI widegap semiconductor alloy"Appl. Phys. Lett.. 72. 2466-2468 (1998)

A. Ohtomo：“Mg_XMgZn_<1-X>O 作为 II-VI 宽禁带半导体合金”Appl。

A.Ohtomo et al.: "Fabrications of allays and superlattices basedonZnO towards Ultraviolet laiers" Materials Science and Engineering. B56. 263-266 (1998)

A.Ohtomo 等人：“基于 ZnO 的紫外层的合金和超晶格的制造”材料科学与工程。