兰州大学机构库 >物理科学与技术学院
慢正电子强束流若干系统研制及氧化钒薄膜微观结构与性能研究
Alternative TitleIntense Slow Positron Beam Facilities (Phase-I)&the Film of Vanadium Oxide
曹兴忠
Thesis Advisor薛德胜 ; 魏龙
2004-05-12
Degree Grantor兰州大学
Place of Conferral兰州
Degree Name博士
Keyword慢正电子 直流化 氧化钒薄膜 微观结构
Abstract本论文将分别介绍慢正电子强束流装置的研制以及钒氧化物薄膜的制备参数、微观结构和性能的研究等工作。 主要就慢正电子束流技术的发展和应用进行叙述,对慢正电子强束流装置中环境辐射的防护、慢正电子束流的产生和输运、脉冲慢正电子的直流化、慢正电子湮没多普勒谱仪的调试和自动化控制系统的设计等工作进行详细描述。严格按照项目设计要求和进度安排,对脉冲慢正电子束流的性能、直流化慢正电子束流性能和应用进行了实验测量和研究。实验结果表明系统设备运行正常,各项基本性能达到了国际同类装置的同等水平。 钒氧化物薄膜的变色特性使其具有广泛的功能材料应用前景,薄膜材料的制备方法、工艺参数和微观结构的研究,有助于改善相关器件的性能,因此有待系统深入的研究。实验采用直流磁控溅射法,通过控制实验条件和衬底材料的选择制备V2O5薄膜。薄膜在真空中退火后,相变形成含有多种价态钒氧化物的VO2薄膜。对氧化钒薄膜的微结构和性能进行分析,系统研究薄膜物理性质与变色性能的关系。对氧化钒薄膜的制备参数和条件的研究发现,氧分压和衬底温度对薄膜的沉积速率和成分,以及晶体生长结构都有影响。
Other AbstractThe development of Intense Slow Positron Beam and the studies of vanadium oxides thin films are introduced in this dissertation. Slow positron beams are interested as a probe method for nuclear and material physical science investigations. But the intensity of beam created by radioactive source is not enough for many important experiments. With the aim of high intensity and new experiment’s techniques in future, an intense slow positron beam has been designed and constructed in IHEP. Slow positrons are extracted from the multi-layered W mesh moderator by a bias voltage and transported for 16 m in vacuum tube by the 100 Gauss magnetic field. Results of electron beam and pulsed positron beam experiments show that the transmission efficiency for positrons is above 98%, the energy spread width of pulsed positron beam is about 10 eV, and the intensity is about 106 e+/s. The image size of pulsed positron beam got by the IP is less than 15 mm. Positrons are stored and moving in P-T in pulse interval. Results show that the intensity is about half of initial after stored 40 ms in 3´10-7 Pa vacuum environment. The energy spread of DC positron beam released with user-defined waveform is less than 1.0 V (FWHM), and. the size of DC positron beam’s image is less than 15 mm too. The counts of DC positron beam measured by HPGe detector in sample chamber are about 2800 cps. Vanadium oxide films are outstanding chromogenic materials. The performance of devices strongly depends on the microstructure and property of films, which influenced by the deposited technique and parameters. V2O5 films are deposited by reactive DC magnetron sputtering. By the vacuum annealing, the phase transition happened from V2O5 film to VO2 film. The surface morphology, microstructure, and composition of films, and phase structure transition are studied. Results show that the V2O5 film is preferential nucleation on (00l) orientation during deposition and the VO2 film is holding the property after vacuum annealing process. V2O5 film offers to excellent cathode and anodic electrochromic optical property at different wavelength range.
URL查看原文
Language中文
Document Type学位论文
Identifierhttps://ir.lzu.edu.cn/handle/262010/229572
Collection物理科学与技术学院
Recommended Citation
GB/T 7714
曹兴忠. 慢正电子强束流若干系统研制及氧化钒薄膜微观结构与性能研究[D]. 兰州. 兰州大学,2004.
Files in This Item:
There are no files associated with this item.
Related Services
Recommend this item
Bookmark
Usage statistics
Export to Endnote
Altmetrics Score
Google Scholar
Similar articles in Google Scholar
[曹兴忠]'s Articles
Baidu academic
Similar articles in Baidu academic
[曹兴忠]'s Articles
Bing Scholar
Similar articles in Bing Scholar
[曹兴忠]'s Articles
Terms of Use
No data!
Social Bookmark/Share
No comment.
Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.