共查询到19条相似文献,搜索用时 149 毫秒
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叙述了在GLZ-100E工业离子注入机上采用20~60 keV氮离子及氮分子离子注入人造金刚石晶体的实验研究。XPS分析表明,注入离子在人造金刚石颗粒表面形成了一层较为稳定的含氮混合物层。高温差热分析(DTA)的实验表明,经氮离子束处理的金刚石,其氧化起始温度T(onset)由原来的730 ℃左右提高到800 ℃以上,且随着氮注入剂量的增加而增加,氧化速度也随之变缓;差热分析还表明,随着温度的升高,金刚石首先转化为石墨(DTA曲线上表现为吸热),然后氧化燃烧生成CO2(放热),而注入离子能量的增加,氧化温度的提高幅度略有下降。离子注入还使其高温石墨化性能显著改善。 相似文献
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当温度超过1 000 ℃时,人造金刚石中的金属触媒包裹体,在形态、结构和成份上都将发生改变,并且这种变化会在金刚石晶格内造成尺寸更大的缺陷区域,因此在表面氧化不起决定性作用的情况下,金属触媒包裹体的这种变化,就成了导致金刚石强度下降的最直接的原因。我们对在氩气保护下、不同温度处理的一系列人造金刚石样品进行了强度测量,并用SEM、X射线衍射及光学显微镜等手段观测了金刚石断裂表面上的包裹体及其形态变化。我们的实验结果证实了上述结论。我们还发现,金属触媒包裹体的存在极大地影响着金刚石的热稳定性,它们使金刚石在1 000 ℃左右即可向石墨转化。 相似文献
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利用微波ECR全方位离子注入技术,在单晶硅(100)衬底上制备类金刚石薄膜.分析结果表明,所制备的类金刚石碳膜具有典型的类金刚石结构特征,薄膜均匀、致密,表面粗糙度小,摩擦系数小.其中,薄膜的结构和性能与氢流量比关系密切,随氢流量比的增加,薄膜的沉积速率减小,表面粗糙度降低,且生成sp3键更加趋向于金刚石结构,表面能 更低,从而使摩擦系数大幅降低.
关键词:
全方位离子注入
类金刚石碳膜
拉曼光谱
摩擦磨损 相似文献
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为了准确评估红外材料和涂层的隐身性能,研制了一套IRS400型材料发射率测试装置,主要用于温度范围(50~400)℃,光谱范围(3~5)m和(8~12)m的固体不透明材料和涂层定向发射率测量。给出IRS400型材料发射率测试装置的技术指标,阐述其工作原理,IRS400的光学系统采用全反射式设计,探测器选用钽酸锂热释电探测器,采用50 ℃~1 000 ℃黑体辐射源标准装置对黑体发射率B(1,2)进行标定。通过解决标定和环境温度补偿等关键技术,确保发射率测量不确定度小于2%(k=2)。 相似文献
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利用FeMn粉末触媒在国产六面顶压机上进行了合成金刚石单晶的实验,研究了高温高压条件下(5.7 GPa、1 550 ℃),石墨-FeMn粉末触媒体系中金刚石单晶的生长特性。通过光学成像显微镜观测表明:合成出的金刚石单晶呈浅黄色,晶形完整,且都是八面体,晶体里含有白色物质,粒度集中在0.3~0.5 mm;通过扫描电镜观测了晶体的表面形貌,表面有熔坑;通过穆斯堡尔谱,发现粉末触媒里主要是FeMn合金和独立状态的Fe,金刚石内部主要是Fe和Fe3C;利用X射线荧光光谱,检测出样品里有Fe和Mn元素。 相似文献
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用射频等离子体方法在玻璃基底上制备的类金刚石(DLC)薄膜,采用离子注入法掺氮,并对掺氮DLC薄膜紫外(UV)辐照前后的性能变化进行了研究。研究结果表明:随氮离子注入剂量及UV辐照时间的增加,位于2 930cm-1附近的SP3C-H吸收峰明显变小,而位于1 580cm-1附近的SP2C-H吸收峰则明显增强,薄膜的电阻率明显呈下降趋势;随UV辐照时间的增加,位于1 078cm-1附近的Si-O-Si键数量及位于786cm-1附近的Si-C键数量明显增加。即氮离子注入和UV辐照明显改变了DLC薄膜的结构与特性。 相似文献
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B.N. Mavrin V.N. Denisov D.M. Popova M.S. Kuznetsov S.A. Terentiev 《Physics letters. A》2008,372(21):3914-3918
For the first time investigations of the boron distribution in the subsurface region of HPHT boron-doped diamond that is promising for applications in electronics were carried out by X-ray photoelectron (XPS) and Raman spectroscopy. It was found from XPS data that the boron content decreased gradually more than one order of magnitude in depth of surface. The first-principle calculations have shown that the Raman polarizability in the crossed polarization configuration should increase considerably with boron doping. The Raman spectra from as-grown and polished surfaces of heavily boron-doped diamond are discussed in the context of theoretical results. 相似文献
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在铁基触媒原材料中添加不同含量的六方氮化硼,采用粉末冶金方法制备片状触媒,在六面顶压机上合成出含硼金刚石单晶。用体视显微镜对金刚石单晶的结构、形貌进行观察,并用电子探针(EPMA)和波谱仪(WDS)分析了金刚石(111)晶面的硼含量,发现金刚石表面有硼元素存在,且其含量随着触媒中掺硼量的增加而变化。在测定了含硼金刚石单晶的静压强度的基础上,采用冲击韧性测定仪和差热分析仪对不同掺硼量触媒合成出的金刚石单晶在空气中的热稳定性进行了系统的对比研究。结果表明,触媒掺硼量对金刚石的机械强度和热稳定性有重要影响,随着掺硼量的变化,其机械强度和热稳定性均存在一个最佳值。 相似文献
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Hong-Xia Zhang Ying-Bing Jiang Q. -B. Meng Yun-Jie Fei Pei-Ran Zhu Zhangda Lin Ke-an Feng 《Applied Surface Science》1999,150(1-4):43-46
Diamond films were doped by boron ion-implantation with the energy of 120 keV. The implantation dose ranged from 1014 to 1017 cm−2. After the implantation, the diamond films were annealed at different temperatures (600–750°C) for different times (2–15 min). Scanning Electronic Microscope, Raman and Secondary Ion Mass-spectrum were used to investigate the effect of boron ion implantation and annealing on the microstructure of the diamond films. The electrical resistivities of the diamond films were also measured. It was found that the best dose of boron ion-implantation into the diamond film was around 1016 cm−2. The appropriate annealing temperature and time was 700°C and 2–5 min, respectively. After implantation, the resistivities were reduced to 0.1 Ω cm (almost nine orders lower than the unimplanted diamond films). These results show that boron ion implantation can be an effective way to fabricate P-type diamond films. 相似文献
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Synthesis and characterizations of boron and nitrogen co-doped high pressure and high temperature large single-crystal diamonds with increased mobility
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Xin-Yuan Miao 《中国物理 B》2021,30(6):68102-068102
We synthesized and investigated the boron-doped and boron/nitrogen co-doped large single-crystal diamonds grown under high pressure and high temperature (HPHT) conditions (5.9 GPa and 1290℃). The optical and electrical properties and surface characterization of the synthetic diamonds were observed and studied. Incorporation of nitrogen significantly changed the growth trace on surface of boron-containing diamonds. X-ray photoelectron spectroscopy (XPS) measurements showed good evident that nitrogen atoms successfully incorporate into the boron-rich diamond lattice and bond with carbon atoms. Raman spectra showed differences on the as-grown surfaces and interior between boron-doped and boron/nitrogen co-doped diamonds. Fourier transform infrared spectroscopy (FTIR) measurements indicated that the nitrogen incorporation significantly decreases the boron acceptor concentration in diamonds. Hall measurements at room temperature showed that the carriers concentration of the co-doped diamonds decreases, and the mobility increases obviously. The highest hole mobility of sample BNDD-1 reached 980 cm2·V-1·s-1, possible reasons were discussed in the paper. 相似文献
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Synergistic influences of titanium,boron, and oxygen on large-size single-crystal diamond growth at high pressure and high temperature
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Guang-Tong Zhou 《中国物理 B》2022,31(6):68103-068103
The synergistic influences of boron, oxygen, and titanium on growing large single-crystal diamonds are studied using different concentrations of B2O3 in a solvent-carbon system under 5.5 GPa-5.7 GPa and 1300 ℃-1500 ℃. It is found that the boron atoms are difficult to enter into the crystal when boron and oxygen impurities are doped using B2O3 without the addition of Ti atoms. However, high boron content is achieved in the doped diamonds that were synthesized with the addition of Ti. Additionally, boron-oxygen complexes are found on the surface of the crystal, and oxygen-related impurities appear in the crystal interior when Ti atoms are added into the FeNi-C system. The results show that the introduction of Ti atoms into the synthesis cavity can effectively control the number of boron atoms and the number of oxygen atoms in the crystal. This has important scientific significance not only for understanding the synergistic influence of boron, oxygen, and titanium atoms on the growth of diamond in the earth, but also for preparing the high-concentration boron or oxygen containing semiconductor diamond technologies. 相似文献