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研究了等离子体工艺参数对射频辉光放电沉积的a-Si:H膜中氢的键合状态的影响及氢在退火时的释放机理。结果表明:可以通过不同的制备条件(特別是等离子体压力)控制a-Si:H膜中氢的键合状态。提出了以空间氢聚团模型解释在a-Si:H膜的退火过程中氢的释放机理。 相似文献
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采用等离子体增强化学气相沉积(PECVD)技术制备薄膜硅/晶体硅异质结,通过测量沉积了本征非晶硅(a-Si:H(i))后晶体硅(c-Si)的少子寿命以及结构为Ag/a-Si:H(p)/a-Si:H(i)/c-Si(n) /Ag 异质结的暗I-V特性,研究了等离子体初期瞬态过程和氢预处理对异质结界面性质的影响。结果表明:使用挡板且当挡板时间(tS)大于100秒时,可以有效地减少等离子体初期瞬态过程对界面性质的负面影响;与热丝化学气相沉积中氢原子处理有利于界面钝化不同,PECVD中的氢等离子体处理,由于氢原子的轰击特性,对钝化可能存在一定的不利影响;最优氢预处理时间为60秒。 相似文献
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一、前言 在电子工业常用的高纯氧、氮、氩等气体中,氢是主要的杂质之一,国内外标准中规定氢杂质含量低于1PPm,因此微量氢的测定是很重要的。在医学上临床应用的氢呼吸试验中,微量氢测定也是关键。用于气体中微量氢测定的气相色谱检测器有热导、氦离子化、放电等。这些检测器均要求使用高纯载 相似文献
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低压气相生长金刚石薄膜成核机理的研究 总被引:1,自引:0,他引:1
本文论述了低压气相生长金刚石薄膜中活性原子团CH_3和原子态氢在金刚石成核运动中的作用以及衬底材料性能对成核的影响,认为活性基CH_3是生长金刚石的主要活性物质,它们在衬底表面的吸附、碰撞、聚集等构成了成核运动,原子氢在成核运动中的主要作用是参与CH_3的脱氢反应和石墨相碳原子团的刻蚀反应,并且还有稳定CH_3中SP ̄3杂化轨道的作用。衬底材料性能对成核的影响在于晶格失配而导致的错配位错和晶格畸变所引起的界面势垒和晶核弹性能的增加。最后讨论了金刚石薄膜与衬底之间是否存在过渡层问题,认为过渡层不是金刚石唯一的成核区,它的存在与生长条件密切相关,并且解释了关于过渡层实验研究中遇到的相互矛盾的结论。 相似文献
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流量及温度对低频PECVD氮化硅薄膜性能的影响 总被引:1,自引:0,他引:1
研究了低频等离子增强化学气相沉积(LF-PECVD)工艺中气体流量比和衬底温度对氮化硅薄膜折射率、密度及应力的影响规律,同时测试了薄膜的红外光谱以分析不同条件对薄膜成分的影响.结果表明,低频氮化硅薄膜折射率主要受薄膜内硅氮元素比的影响,其次是薄膜密度的影响.前者主要由硅烷/氨气反应气体流量比决定,而后者主要由衬底温度决定;低频氮化硅薄膜应力大致与密度成正比关系.此外,PECVD工艺所制备氮化硅薄膜都含有相当数量的氢元素,而衬底温度是薄膜内氢含量的决定因素. 相似文献
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近年来,通过在低温领域中的碳化氢等的气相分解,使金刚石那样的非平衡碳素的析出成为可能。但是,在低温低压下要使非平衡状态的金刚石析出,还需要在低温低压下形成与高温高压下构成金刚石的碳原子同样的结合状态。这样,就研究了在气相中生成具有SP~3杂 相似文献
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In the current study, the effects of the wick structures and working fluids characteristics on U-shape heat pipe performance were numerically presented. A two-dimensional FEM simulation was performed on U-shape heat pipe to analyze the temperature and the pressure distributions inside the heat pipe. In order to reduce the pressure arising in the area of the wick to increase heat transport capability at the liquid-wick region, a comparative numerical study was made by using methanol and water as working fluids with sintered powder and screen mesh wicks. The simulation was performed by using ANSYS/FLOTRAN software with heat input of 10 W at forced convection. The results showed that the use of sintered copper powder wick resulted in a small temperature difference between the evaporator and condenser compared to screen mesh wick. The use of screen mesh wick caused a decrease in the pressure drop in liquid-wick region while the use of methanol as working fluid increased the liquid pressure drop. 相似文献
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利用激光光内送粉熔覆技术,在与水平方向成大于90的仰面基体下表面进行了单道熔覆实验研究。分析了仰角、保护气压力与光粉耦合处粉束直径之间的关系;研究了仰面姿态下熔覆层的宽度、高度以及熔池的流淌下垂趋势受激光功率、扫描速度的影响规律。研究发现,光粉耦合处粉束直径随仰角的增大而变大,随保护气压力的增大而减小。基体仰面与水平姿态下,工艺参数对熔覆层的宽度、高度的影响规律保持了较好的一致性;熔池在重力作用下,激光功率、扫描速度以及仰角的变化对熔覆层高度的影响更加显著;熔道顶点的偏移随激光功率的减小、扫描速度的增大和仰角的增大而逐渐增小。保持送粉量和离焦量不变,利用优化后的激光功率、扫描速度,以及保护气压力,获得了最大仰角达150、且具有较好尺寸精度和组织性能的激光熔覆立体成形件。 相似文献
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Shang-Chou Chang Tien-Chai Lin To-Sing Li Sheng-Han Huang 《Microelectronics Journal》2008,39(12):1572-1575
To find the possibility of using a low-temperature process in growing carbon nanotubes (CNTs), nickel catalyst converted from film into particles by microwave H2/N2 plasma and the following CNT growth are all kept at a low temperature of 250 °C. The flat panel display industry requests low-temperature rather than the traditional high-temperature process for CNT growth. It was found that H2/N2 proportion is very sensitive to nickel morphology and the subsequent CNT growth. Better nickel and CNTs morphology are obtained for the proportion H2/N2=3/1 than those for the generally used pure hydrogen environment. The process pressure selection during pretreatment can determine whether CNTs are grown or not. The diameter of growing CNTs is proportional to nickel particle size. Field emission results support field amplification coefficient claim. The long tube length and high tube density of growing CNTs demonstrate low threshold electric field. This work shows the potential to use H2/N2 instead of pure hydrogen plasma in growing qualified CNTs applied in display industry. 相似文献
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A new low-temperature assembly process using a new class of isotropic conductive adhesives (ICAs) with fusible filler particles
was proposed to realize a low-temperature, fluxless and cost-effective, alternative, solder flip-chip interconnection technology.
New ICA formulations were developed using two different resin materials and fusible filler particles. The curing behavior
of the resin materials and the melting of the fusible filler were observed by differential scanning calorimetry (DSC). The
coalescence and wetting states, the size distribution of the fusible fillers, and the formation of the conduction path in
each ICA formulation were observed with a laser microscope. It was found that two different types of electrical conductive
paths, necking type and bump type, were produced. The bump-type conductive path was more effective than that of the necking
type in achieving a lower electrical resistance through resistance measurement. The reduction capability of the base resin
material was effective for the coalescence and the wetting of the fusible fillers and affected the conductive path type. A
good metallurgical connection was formed between the fusible fillers in ICAs and between the fusible fillers and the copper
surface even at the lower filler-volume fraction of 30%. 相似文献
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采用燃烧合成法制备碳化硅(SiC)粉料,调整氢气和氩气体积流量比以及高纯氯化氢气体体积流量,使氮、铝和钒浓度低于二次离子质谱仪的检测下限,硼和钛浓度接近检测下限。使用制备的高纯SiC粉料生长单晶,获得电阻率大于1×10^9Ω·cm的衬底,粉料达到高纯半绝缘水平。通过研究发现,增加氢气体积流量可以降低粉料中的氮浓度,并使氮浓度低于检测限1×10^16 cm^-3,但是氢气体积流量过高会加重坩埚损耗,影响坩埚寿命和工艺稳定性;高纯氯化氢气体可以降低粉料中硼、铝、钒和钛的浓度,但其体积流量不宜过大,否则会引入新的氮杂质;粉料的色度a^*值与氮浓度呈反比关系,利用分光色差仪测试色度a^*值判断粉料氮浓度高低。 相似文献
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Ch. Zach Dr. Geschäftsführerin H. Jernej Dr. 《e & i Elektrotechnik und Informationstechnik》2005,122(11):401-403
If hydrogen is to be promoted as a fuel of the future, established and tried-and-tested organisational structures and working methods must be complemented by flexible instruments capable of ensuring a maximum of innovation, productivity and information exchange with a wide range of players. The platform structure provides the ideal environment for sustainable development processes. 相似文献
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利用NiOx薄膜具有优良的电致变色性能,制备了透过率可实时调整的PDP屏滤光膜以提高PDP屏的出光效率,在不同环境照度下获得更好的图像质量。采用扫描电镜(SEM)、X射线衍射仪(XRD)、分光光度计研究了采用磁控溅射法制备的NiOx薄膜中镍的含量对薄膜光电特性的影响。分析测试结果表明:溅射时随着氧分压的提高,氧化镍薄膜的镍含量明显降低;NiOx薄膜中镍原子含量为45%左右时,NiOx薄膜对可见光透过率的调节能力最强,其最高透过率与最低透过率差值达70%。 相似文献