首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
结合激光退火与常规热退火方法对超薄非晶硅层作用,在绝缘衬底上获得了高密度的、均匀的单层纳米硅结构.所得样品通过原子力显微镜、透射电子显微镜和Raman散射谱进行表征,证实了晶化过程的发生和纳米硅晶粒的形成.在得到的5nm厚晶化样品中观察到在660nm左右范围内光致发光峰,初步的分析表明其发光与纳米硅晶粒的形成有关.  相似文献   

2.
为实现基于硅基材料的高效光源,提出激光晶化形成纳米硅基电致发光材料性能研究,来明确了激光晶化形成纳米硅基电致发光材料的基本性能。主要以选择的纳米硅基电致发光材料作为研究对象,首先采用激光晶化技术完成制备工作,其次设计对电致发光材料性能计算方法,最后设计吸收光谱、固态与薄膜态量子产量、发光寿命、发光率四方面的测定环节,依此对晶化处理和未晶化的两个样本进行电致发光材料测定。结果表明:晶化后的电致发光材料中存在尺寸可控的纳米硅量子,且当氧气量充足时,晶化后的致电发光材料的硅粒子产出量会逐渐增加;光学带隙要比原始沉积样本要小,且当精光密度增加时光学带隙发生进一步缩减;晶化后的样本发光寿命有、无氧两种状态均为1 200 ns,发光率可达到99%。以上结果说明激光晶化形成纳米硅基电致发光材料性能优越,具有较强的发展潜力。以期可为日后的纳米硅基电致发光材料研究与制作过程中提供理论支撑,在此基础上制备出性能更加优异的电致发光材料。  相似文献   

3.
徐伟  严敏逸  许杰  徐骏  黄信凡  陈坤基 《中国激光》2012,39(7):706003-168
采用等离子体化学气相沉积技术制备了两种不同非晶硅层厚度的氮化硅/氢化非晶硅/氮化硅三明治结构,研究了不同能量激光退火对薄膜晶化的影响。通过拉曼分析,发现在激光能量为320mJ时,样品开始晶化,随着能量的提高晶化程度增加,在340mJ时达到最大。根据拉曼晶化峰的偏移,计算得出硅量子点尺寸为2.8nm和4.7nm,表明三明治结构对形成的硅量子点的尺寸具有限制作用。设计并制备了基于该结构的电致发光器件,在偏压大于10V时,在室温下可观测到电致发光。发现不同激光能量下晶化后的样品的电致发光强度不同,发光峰位在680nm和720nm附近。分析表明电致发光来源可以归结为电子空穴对在硅量子点中的辐射复合发光。  相似文献   

4.
利用相移光栅模板使KrF准分子激光形成强度周期分布的激光束,定域晶化a-Si∶H(4nm)/a-SiNx∶H(10nm)多层膜中的超薄a-Si∶H层,成功地制备出了三维有序分布的nc-Si阵列。原子力显微镜(AFM)、微区喇曼光谱、剖面透射电子显微镜(X-TEM)及高分辨电子显微镜(HREM)技术分析揭示了晶化后薄膜中形成了横向周期与移相光栅周期相同、纵向周期与a-Si∶H/a-SiNx∶H多层膜周期(14nm)相等的nc-Si阵列。  相似文献   

5.
安志斌  沈晓骏  高山  姚晨光  汪诚 《红外与激光工程》2016,45(9):921002-0921002(6)
针对K403镍基高温合金铸造构建易发生裂纹、腐蚀、磨损的问题,采用激光冲击强化技术对K403薄片试件进行处理,使试件表面纳米化提高材料力学性能。利用X射线衍射、SEM扫描电镜、TEM透射电镜分析了材料表面纳米晶层的形成机理。实验结果表明:激光诱导的高压等离子体冲击波可以在样品表面上形成226 nm厚的纳米晶层;从SEM和TEM结果可以看出,激光冲击强化不会改变材料表面物相。在高冲击波压力下,K403试样表面组织产生了位错和纳米级晶粒细化。  相似文献   

6.
SAPO—5分子筛结晶过程的SEM,EDAX研究   总被引:2,自引:0,他引:2  
采用不同的硅源和晶化时间合成的了一系列SAPO-5分子筛。用扫描电镜(SEM)观察不同晶化阶段分子筛的晶体及晶粒大小,用EDAX分析不同样品及同一样品中不同晶粒的元素组成.所得结果表明:当以SiO_2为硅源时,优先生成低硅含量的SAPO-5分子筛晶粒。随晶化时间加长,硅逐渐取代磷进入分子筛骨架并使分子筛晶形改变,晶粒变小。当晶化时间达72h时,产物中伴生有SAPO-34,而以Si(OEt)_4为硅源时,硅对磷的取代速度较慢、随晶化时间的增长,硅进入分子筛骨架并使其晶形变得更加规则。实验结果还暗示,SEM结合微区EDAX是分辨结晶物中无定形硅的有效手段。  相似文献   

7.
采用新电极结构的PECVD技术,在高功率密度、高氢稀释比、低温、偏压及低反应气压的条件下,在SiO2玻璃表面形成双等离子流,增加了SiO2表面SiC的成核几率,增强成核作用,形成纳米晶。采用高H2等离子体刻蚀弱的、扭曲的、非晶Si-C及Si-Si和Si-H等键时,由于H等离子体对纳米SiC晶粒与非晶态键的差异刻蚀作用,产生自组织生长,发生晶化。Raman光谱和透射电子衍射(EM)的测试结果表明,纳米晶SiC是4H-SiC多型结构。实验结果指出,SiC纳米晶的形成必须经过偏压预处理成核,并且其晶化存在一个功率密度阈值;当低于这一功率密度阈值时,晶化消失;当超过这一阈值时,纳米晶含量随功率密度的提高而增加,晶粒尺寸加大。电子显微照片表明晶粒尺寸为10-28nm,形状为微柱体。随着晶化作用的加强,电导率增加,导电机理是渗流作用所致。  相似文献   

8.
采用独特的快速循环纳米晶化技术(RRTA)对直流磁控溅射制备的非晶CoNbZr软磁膜进行纳米晶化。研究了不同的纳米晶化工艺条件下,薄膜的微观结构和软磁性能。结果表明,CoNbZr软磁薄膜晶粒细化到30 nm,RRTA晶化方法可有效地控制CoNbZr薄膜的软磁性能。  相似文献   

9.
1kHz的飞秒激光辐照在非晶硅薄膜后会使得辐照区域的薄膜产生晶化现象.拉曼光谱表明这个激光诱导晶化过程与入射激光的能量及其模式分布有密切的联系.扫描电镜观测发现激光辐照区域形成了粗糙的表面纹理,并且大量的晶粒形成在这个结构表面.这个晶化现象可能是由于爆炸晶化成核和晶粒外延生长共同作用的结果,进一步的研究表明这种飞秒激光...  相似文献   

10.
将采用传统电化学腐蚀法制备的多孔硅样品,用浸泡液浸泡剥离其表层多孔层,使样品表面形成SiO2包裹纳米硅颗粒的结构,在表面镀半透明Au膜后制备成电致发光器件.在正向偏压下样品可以长时间稳定地发出绿光(510nm),并且随着偏压的升高,发光强度增强,峰位不变.讨论了可能的发光机制.  相似文献   

11.
DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.  相似文献   

12.
From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.  相似文献   

13.
The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.  相似文献   

14.
The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.  相似文献   

15.
Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.  相似文献   

16.
Waveguide multilayer optical card (WMOC) is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling & processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic (VB) language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.  相似文献   

17.
This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel's.  相似文献   

18.
The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.  相似文献   

19.
Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.  相似文献   

20.
An insert layer structure organic electroluminescent device(OLED) based on a new luminescent material (Zn(salen)) is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn(salen)/Liq/LiF/A1/CuPc/NPD/Zn(salen)/Liq/LiF/A1. Effective insert electrode layers comprising LiF(1nm)/Al(5 nm) are used as a single semitransparent mirror, and bilayer cathode LiF(1 nm)/A1(100 nm) is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号