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文内报告了金刚石薄膜/立方氮化硼异质结的制备过程,然后采用自制的 测试装置对其伏-安特性进行了测试。 相似文献
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高质量宽带隙立方氮化硼薄膜的研究进展 总被引:1,自引:0,他引:1
文章着重介绍了最近研制出的高质量宽带隙立方氮化硼薄膜的三种制备方法和结构特性 :(1)用射频溅射法在Si衬底上制备出立方相含量在 90 %以上 ,Eg>6 .0eV的c-BN薄膜 ;(2 )用离子束辅助的化学气相沉积法(CVD) ,在金刚石上外延生长出立方含量达 10 0 %的单晶c -BN薄膜 ;(3)用微波电子回旋共振CVD法 (MW -ECR-CVD)在金刚石上外延生长出高纯c-BN薄膜 .这些高纯c -BN薄膜 ,可应用于制作各种半导体 (主要是高温、高频大功率 )电子器件 . 相似文献
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文内报告了尺寸为0.3×0.3 mm2的立方氮化硼单晶的N-型掺杂,然后 用特殊的测量装置测量了N-型立方氮化硼的欧姆接触之后的伏-安特性。 相似文献
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本文简要介绍了等离子体化学气相沉积的基本原理和几种主要类型的工艺特点,着重介绍了等离子体化学气相沉积在沉积超硬膜方面的新进展,主要包括制备氮化钛类薄膜、立方氮化硼薄膜、类金刚石薄膜及金刚石薄膜。 相似文献
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采用磁增强活性反应离子镀系统成功地合成了立方氮化硼薄膜.通过给基片施加脉冲直流偏压以代替传统的射频偏压,增强了立方氮化硼的成膜稳定性,研究了基片的直流脉冲偏压、等离子体放电电流、通入气体流量比(Ar/N2)和基片温度沉积参数对立方氮化硼薄膜形成的影响规律.结果表明:随着基片负偏压和放电电流的增大,薄膜中立方氮化硼的纯度提高,当基片负偏压为155V,放电电流为15A时,可获得几乎单相的立方氮化硼薄膜.基片温度为500℃和Ar/N2流量比为10时,最有利于立方氮化硼
关键词:
立方氮化硼
活性反应离子镀
脉冲偏压 相似文献
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采用了基于密度泛函理论(DFT)的第一性原理平面波超软赝势方法,计算了本征ZnO, W单掺杂ZnO, Cu单掺杂ZnO,以及W-Cu共掺杂ZnO电子结构和光学性质.计算结果表明:W掺杂属于n型掺杂, Cu掺杂属于p型掺杂,单掺杂均可以提高ZnO的载流子浓度,从而改善ZnO的导电性. W-Cu共掺杂时ZnO进入简并状态,呈现金属性质.三种掺杂ZnO的吸收光谱均发生红移,其中W-Cu共掺杂时, ZnO对太阳光谱的吸收效果最好. 相似文献
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在密度泛函理论和线性响应的密度泛函微扰理论基础上的第一性原理计算的方法研究了Ca掺杂对纤锌矿结构氧化物ZnO热学参数和热学性能的影响。研究结果表明,Ca掺杂ZnO氧化物晶格a,b,c轴均有所增大;在计算温度区间,纯的ZnO和Ca掺杂的ZnO的晶格热容均随温度升高不断增大;Ca掺杂的ZnO具有较高的晶格热容;纯的ZnO和Ca掺杂的ZnO的晶格热容在最高温度900K分别达到16.5 Cal.mol-1K-1和31.7Cal.mol-1K-1。纯的ZnO和Ca掺杂的ZnO的德拜温度 均随温度升高不断增大,Ca掺杂的ZnO的德拜温度 均高于纯的ZnO。Ca掺杂在ZnO中引入了新的振动模式。Ca掺杂ZnO氧化物应该具有较高的晶格热导率。 相似文献
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通过溶胶凝胶自燃法合成锰掺杂氧化锌纳米晶体, 研究了Mn掺杂ZnO稀磁半导体(简称DMS)的性质.X射线衍射光谱表明,锰掺杂氧化锌保留纤锌矿型状氧化锌六角晶体结构.采用能量色散X射线能谱和扫描电子显微镜分别对成分和形态进行研究.温度依赖的电阻率显示了DMS的半导体材料行为.振动样品磁强计测定的室温磁性行为,揭示了锰掺杂氧化锌的铁磁性和反磁性特性. 相似文献
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在密度泛函理论和线性响应的密度泛函微扰理论基础上的第一性原理计算的方法研究了Ca掺杂对纤锌矿结构氧化物ZnO热学参数和热学性能的影响。研究结果表明,Ca掺杂ZnO氧化物晶格a,b,c轴均有所增大;在计算温度区间,纯的ZnO和Ca掺杂的ZnO的晶格热容均随温度升高不断增大;Ca掺杂的ZnO具有较高的晶格热容;纯的ZnO和Ca掺杂的ZnO的晶格热容在最高温度900K分别达到16.5 Cal.mol-1K-1和31.7Cal.mol-1K-1。纯的ZnO和Ca掺杂的ZnO的德拜温度 均随温度升高不断增大,Ca掺杂的ZnO的德拜温度 均高于纯的ZnO。Ca掺杂在ZnO中引入了新的振动模式。Ca掺杂ZnO氧化物应该具有较高的晶格热导率。 相似文献
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GUO Yang LIU Yao-Ping LI Jun-Qiang ZHANG Sheng-Li MEI Zeng-Xia DU Xiao-Long 《中国物理快报》2010,27(6):171-174
A Van der Pauw Hall measurement is performed on the intended doped ZnO films (Na doped ZnO) grown by using the molecular beam epitaxial method. All as-grown samples show n-type conductivity, whereas the annealed samples (annealing temperature 900℃) show ambiguous carrier conductivity type (n- and p-type) in the automatic Van der Pauw Hall measurement. A similar result has been observed in Li doped ZnO and in as-doped ZnO films by other groups before. However, by tracing the Hall voltage in the Van der Pauw Hall measurement, it is found that this alternative appearance of both n- and p-type conductivity is not intrinsic behavior of the intended doped ZnO films, but is due to the persistent photoconductivity effect in ZnO. The persistent photoconductivity effect would strongly affect the accurate determination of the carrier conductivity type of a highly resistive intended doped ZnO sample. 相似文献
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Fei Ye Toshiyuki Mori Ding Rong Ou Alastair N. Cormack 《Solid State Ionics》2009,180(20-22):1127-1132
Defect clusters in several rare-earth-doped ceria (doped with Y, Sm, Gd, Dy and Yb) containing up to four oxygen vacancies and eight dopant cations have been simulated and compared. In all doped ceria systems, the binding energy of the clusters increases with increasing cluster size and the oxygen vacancies tend to form curved chains in the clusters. Moreover, the capability of the growth of defect cluster is affected by dopant type, which can explain the dopant type dependency of domain development with increasing doping concentration in heavily doped ceria. 相似文献
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The current density–voltage characteristics of pure and iodine doped plasma polymerized 2,6-diethylaniline (PPDEA) thin films of different thicknesses ranging from 150 to 450 nm with aluminum (Al)/PPDEA/Al structure have been investigated at room temperature. The direct current electrical conductivity has showed a higher value due to iodine doping of PPDEA thin film. In contrast to pure PPDEA thin films where the most probable conduction mechanism is electrode limited Schottky type, Poole–Frenkel (PF) conduction mechanism is found to be operative in iodine doped PPDEA thin films. The PF conduction mechanism in iodine doped PPDEA thin films may have generated due to the charge transfer complex formation through donor type monomer and acceptor type iodine. The presence of charge transfer complex is confirmed by a new absorption shoulder/peak in ultraviolet–visible spectrum of iodine doped PPDEA thin film. 相似文献
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U. Schoop M. Schonecke S. Thienhaus F. Herbstritt J. Klein L. Alff R. Gross 《Physica C: Superconductivity and its Applications》2001,350(3-4):237-243
We have studied heteroepitaxially grown ramp type structures consisting of high-temperature superconductors (HTS) and doped manganites in various configurations. Firstly, the coupling of two HTS electrodes via doped manganite barriers was analyzed and secondly the interface properties between HTS and doped manganites as well as between doped manganites with different Curie temperatures have been investigated. As a common feature of the interfaces involving doped manganites an increase in resistance at low temperatures was found which appears together with non-linear current–voltage characteristics. On applying external magnetic fields up to 8 T, the low temperature interface resistance is suppressed considerably. These observations can be understood in terms of a spin glass behavior of the doped manganites just at the interface caused by strain due to lattice misfit and disorder. The differential conductance spectra of YBa2Cu3O7−δ–La2/3Ca1/3MnO3 junctions with low transparency show a pronounced gap feature but no zero-bias conductance peak. 相似文献
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杂质银对氧化锌薄膜气敏光学特性的影响 总被引:4,自引:1,他引:3
用反应式射频磁控溅射方法制备了纯氧化锌(ZnO)薄膜和掺Ag的ZnO气敏光学传感薄膜。测量了这些薄膜在NOx气体中的透射光谱,然后由透射光谱获得了灵敏度的变化规律,发现掺Ag后的ZnO薄膜对NOx气体的灵敏度高于纯ZnO薄膜,用俄歇电子能谱(AES)测试了这些薄膜的组分,发现当掺Ag量为5%时灵敏度最高,并结合朗缪尔(Langmuir)型吸附平衡关系式解释了这些现象,理论和实验结果能很好的相符。 相似文献
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P. Chutia Chandrani Nath A. Kumar 《Applied Physics A: Materials Science & Processing》2014,115(3):943-951
The present work investigates the electrical transport and dielectric relaxation of polyaniline (PAni) nanorods doped with organic camphorsulfonic acid (CSA) and inorganic hydrochloric acid (HCl) synthesized by interfacial polymerization technique. High resolution transmission electron micrographs (HRTEM) depict that initially spherical nuclei directionally grow into nanorods and CSA doped PAni produces more uniform and aligned structures. The electrical transport studies reveal that the CSA doped nanorods follow 1D Mott variable-range hopping (VRH), whereas the HCl doped nanorods exhibit 2D VRH conduction mechanism. The value of interchain charge transfer integral is found to be higher for smaller size HCl doped PAni than that for larger size CSA doped PAni. The resistivity measurements exhibit semiconducting behavior for both organic and inorganic dopants and the resistivity of the CSA doped nanorods is found to be smaller than that of the HCl doped nanorods. The dielectric relaxation studies suggest Debye type relaxation with a single relaxation peak for both the dopants and the relaxation time of the carriers of the CSA doped PAni nanorods is smaller than that of the HCl doped nanorods. 相似文献