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MOCVD法制备磷掺杂p型ZnO薄膜 总被引:1,自引:0,他引:1
利用金属有机化学气相沉积方法在玻璃衬底上生长了掺磷的p型ZnO薄膜.实验采用二乙基锌作为锌源,高纯氧气和五氧化二磷粉末分别作为氧源及磷掺杂源.实验表明:生长温度为400~450℃时获得了p型ZnO薄膜,而且在420℃时,其电学性能最好,空穴浓度为1.61×1018cm-3,电阻率为4.64Ω·cm,迁移率为0.838cm2/(V·s).霍尔测试和低温光致发光谱证实了该ZnO薄膜的p型导电特性,并观察到薄膜位于3.354eV与中性受主束缚激子相关的发射峰. 相似文献
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研究了反应压力对金属有机化学气相沉积(MOCVD)技术制备未掺杂ZnO薄膜的微观结构和光电特性影响.X射线衍射(XRD)和扫描电子镜(SEM)的研究结果表明,随着反应压力的降低,ZnO薄膜(002)择优峰的强度呈现相对减弱趋势,并且出现了较强的(110)峰;Hall测量表明,低的反应压力有助于提高薄膜电学特性.200 Pa时制备出的ZnO薄膜具有明显的"类金字塔"状绒面结构,电阻率为1.28×10-2 Ω·cm.实验中沉积的ZnO薄膜在600~2 600 nm内平均透过率超过80%,而短波长范围由于光散射作用,ZnO薄膜的垂直透过率有所下降. 相似文献
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采用金属有机物化学气相沉积(MOCVD)方法,以NH3作为N元素的掺杂源,在蓝宝石衬底上生长了掺N的ZnO薄膜.利用X射线衍射、X射线光电子能谱、原子力显微镜、霍尔测量及先致荧光光谱等测试技术分析了薄膜的结晶性质、表面形貌、光电性质及掺杂元素N的价键特性.结果表明,NH3 的掺杂会影响ZnO薄膜的结晶特性,薄膜虽然仍是(002) 面择优取向生长,但同时也出现了ZnO的(100)及(101)面生长.在薄膜生长时N元素掺入到ZnO薄膜当中,并形成N-Zn、N-H、N-C键.C、H杂质的存在,使掺N ZnO薄膜表现为高阻,同时也影响了薄膜的光致发光特性. 相似文献
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采用低压-金属有机化学气相沉积(MOCVD)技术,结合正交试验设计,在(100)p-Si衬底上制备了高质量的ZnO薄膜.用室温光致发光研究了不同生长参数对ZnO薄膜光学质量的影响.通过正交分析法对所得样品相关特征指标的分析,得到生长温度、锌源温度和氧气流量3个独立工艺参数对薄膜光学质量的影响.结果表明,生长温度对薄膜光学质量的影响最大,其余依次为氧气流量和锌源温度,同时,通过分析还得到了最佳组合工艺.结合面探X射线衍射仪,分析了薄膜的结晶质量,发现在优化的工艺条件下制备出的ZnO薄膜具有较好的结晶质量. 相似文献
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By means of exact conformal mapping method we have defined character of dependence of squares amounts of angular part of film
element on angled part dimension. We propose relations, approximating obtained dependence. Calculation results and experimental
researches of large-scale models are represented. 相似文献
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Moshrefzadeh R.S. Radcliffe M.D. Lee T.C. Mohapatra S.K. 《Lightwave Technology, Journal of》1992,10(4):420-425
The temperature dependence of refractive index of polymer films was determined for a number of slab waveguides by a grating coupling method. This dependence was examined as a function of parameters such as molecular weight and glass transition temperature of the polymer. Temperature-induced changes in N TE-N TM , N being the effective index, were studied systematically for different slab waveguide compositions. It is shown that with proper device design and choice of polymeric materials, thermal effects can be reduced 相似文献
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The article describes a model representation of radar probing data in form of a mixture of background and target samples, which is the sum of two random variables with very different parameters. For model development we research the behavior of the central moments of the distribution mix without assuming the distribution law form. An example it is described the detection of the signal at the output of compression system of chirp ionosonde. 相似文献
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罗晓羽 《信息技术与标准化》2008,(6):37-39
论述了推进电子行业标准制修订项目计划管理信息化的必要性.并提出了具体措施;详细介绍了电子行业标准制修订项目计划管理数据库的设计思路和实现方法.阐述了对后续工作的几点思考. 相似文献
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对影响镍镀层内应力的因素做了介绍和分析,提出了对收缩应力的一种解释,提供了排除这些因素影响的方法,指出重视镀液的管理是减少各种影响内应力因素的主要办法。 相似文献
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The approaches to prepare a uniform and unified scientific terminology of chemical carcinogenesis are presented. The main definitions proposed (carcinogen, initiation, promotion, mutagen, multistage carcinogenesis, anti-carcinogen, cocarcinogen, carcinogenic risk, etc.) are based on the current state of comprehending mechanisms of the action of chemical carcinogens. 相似文献
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解决IP网QoS问题是目前通信领域的研究热点之一.虽然研究已经取得了一定的进展,但人们对于IP 网QoS本身的含义及相关的问题还有着不同的理解.本文将从IP网QoS的定义入手讨论相关的一些问题以及解决IP网QoS问题所做的各种努力. 相似文献
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《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1968,56(6):1024-1032
Assuming that visual responses are due to the action of particles on the membrane of the visual cells, the stochastic variability of the response should be a function of the number of particles producing it. Quantitative predictions can be made with the aid of a model proposed in previous articles. It is found that responses produced in visual cells of Limulus by absorption of a single photon have the stochastic properties which would be expected if the response to one photon were brought about by 25 particles. It is concluded from this that the processes leading to visual responses produce multiplication of particles. The effects of temperature and of metabolic poisons suggest that these processes are of chemical nature. 相似文献