共查询到20条相似文献,搜索用时 125 毫秒
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利用磁控溅射和热退火在硅衬底上制备了Ag纳米颗粒镶嵌的氧化硅薄膜(SiO2∶ Ag),制作了电致发光结构ITO/SiO2∶Ag/p-Si,观测到了可见区的电致发光.发现薄膜中的Ag纳米颗粒不仅成倍地提高器件的发光强度,还明显地移动电致发光的峰位.Ag含量越高,颗粒越大,发光峰位越红移.氧化硅中的发光中心与纳米Ag间的电... 相似文献
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掺铒纳米晶硅和掺铒非晶纳米硅薄膜的发光性质 总被引:3,自引:1,他引:2
采用等离子体增强化学气相沉积(PECVD)方法制备含有纳米晶硅的SiO2(NCSO)和含有非晶纳米硅颗粒的氢化非晶氧化硅(a—SiOx:H)薄膜。采用离子注入和高温退火方法将稀土Er掺入含有纳米晶硅(ncSi)和非晶纳米硅(a—n—Si)颗粒的基体中。利用IFS/20HR傅里叶变换红外光谱仪和微区拉曼散射光谱仪研究含有纳米晶硅和非晶纳米硅颗粒的薄膜掺稀土前后的发光特性。结果表明来自Be-Si在800nm的发光强度比来自a—SiOx:H基体中非晶纳米硅的发光强度高近一个数量级,而来自a-SiOx:H在1.54μm的发光强度比NCSO高4倍。还研究了掺铒a-SiOx:H薄膜中Si颗粒和Er^3+的发光强度随退火温度的变化,结合掺铒纳米晶硅和非晶纳米硅薄膜发光强度随Er掺杂浓度变化和Raman散射等的测量结果,进一步明确指出a-Si颗粒在Er^3+的激发中可以起到和nc-Si同样的作用,即作为光吸收介质和敏化剂的作用。 相似文献
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《物理学报》2001,50(8):1580-1584
分别以硅-二氧化硅和锗-二氧化硅复合靶作为溅射靶,采用磁控溅射技术在p型硅衬底上淀积了含纳米硅的氧化硅薄膜和含纳米锗的氧化硅薄膜.各样品分别在氮气氛中经过300至1100℃不同温度的退火处理.使用高分辨透射电子显微镜可以观察到经900和1100℃退火的含纳米硅的氧化硅薄膜中的纳米硅粒,和经900和1100℃退火的含纳米锗的氧化硅薄膜中的纳米锗粒.经过不同温度退火处理的含纳米硅的氧化硅和含纳米锗的氧化硅薄膜的光致发光谱均具有相似的峰型,且它们的发光峰位均位于580nm(2.1eV)附近.可以认为含纳米硅的氧化硅和含纳米锗的氧化硅薄膜的光发射主要来自于SiO 相似文献
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分别以硅-二氧化硅和锗-二氧化硅复合靶作为溅射靶,采用磁控溅射技术在p型硅衬底上淀积了含纳米硅的氧化硅薄膜和含纳米锗的氧化硅薄膜.各样品分别在氮气氛中经过300至1100℃不同温度的退火处理.使用高分辨透射电子显微镜可以观察到经900和1100℃退火的含纳米硅的氧化硅薄膜中的纳米硅粒,和经900和1100℃退火的含纳米锗的氧化硅薄膜中的纳米锗粒.经过不同温度退火处理的含纳米硅的氧化硅和含纳米锗的氧化硅薄膜的光致发光谱均具有相似的峰型,且它们的发光峰位均位于580nm(2.1eV)附近.可以认为含纳米硅的氧化硅和含纳米锗的氧化硅薄膜的光发射主要来自于SiO2层中发光中心上的复合发光,对实验结果进行了合理的解释 相似文献
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溶胶-凝胶法制备Ce3+掺杂纳米SiO2材料光致发光研究 总被引:3,自引:0,他引:3
通过溶胶-凝胶技术制备了掺杂Ce^3+离子的纳米SiO2材料,并经较低温度下煅烧,研究其光致发光(PL)性能。X射线衍射(XRD)及透射电子显微镜(TEM)测试结果表明该纳米材料具有非晶态结构,颗粒尺寸为20~30nm。对其光致发光谱的测定显示:经450℃低温煅烧,未掺杂SiO2样品的光致发光谱明显为多峰的宽带结构,而微量Ce^3+掺杂的样品在230nm激发下存在着唯一的一个很强的、主峰位于346nm左右的紫外发光峰,与未掺杂SiO2及Cu^2+掺杂SiO2样品的比较表明该发光峰并非常见的Ce^3+离子的d-f跃迁产生的特征发光带,而是起源于SiO2中的某种本征缺陷中心。通过不同煅烧温度以及不同Ce^3+离子掺杂量对346nm发光峰强度的影响,讨论该发光峰起源可能的结构模型。 相似文献
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采用溶胶法制备了Mn掺杂的ZnS纳米粒子,探讨了掺杂离子浓度对ZnS∶Mn纳米粒子的晶体结构和发光性质的影响。通过X射线衍射(XRD)对样品的结构进行了表征,结果表明:所制备的ZnS∶Mn纳米粒子为立方闪锌矿结构,其在Mn离子的掺杂浓度达到6%时不发生分相,但随着掺杂浓度的增加,纳米粒子的平均粒径会减小。光致发光光谱和荧光光谱的结果表明:通过改变掺杂离子的浓度可实现对ZnS∶Mn纳米粒子590 nm附近荧光发射波长的调节。此外,研究了温度对纳米粒子形貌和发光性质的影响。高分辨透射电子显微镜(HRTEM)观察发现,经过50℃陈化1 h后的ZnS∶Mn样品的平均粒径增大约为20 nm,且加热陈化有利于ZnS∶Mn纳米粒子中Mn2+在590 nm处产生荧光。 相似文献
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报道了硅基有机微腔的电致发光(EL).该微腔由上半透明金属膜、中心有源多层膜和多孔硅分布Bragg反射镜(PS DBR)组成.半透明金属膜由Ag(20nm)构成,充当发光器件的负电极和微腔的上反射镜.有源多层膜由Al (1 nm) / LiF(05 nm) /Alq3/Alq3:DCJTB/NPB/CuPc/ITO/SiO2组成,其中的Al/LiF为电子注入层,ITO为正电极,SiO2为使正、负电极电隔离的介质层.该PS DBR是采用设备简单、成本低廉且非常省时的电化学腐蚀法用单晶Si来制备的;该PS
关键词:
电化学腐蚀
电致发光
窄峰发射
硅基有机微腔 相似文献
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采用甚高频增强型等离子体化学气相沉积技术,通过优化薄膜的沉积条件制备出高性能的P nc Si∶H薄膜材料(σ=5.86 S/cm、Eopt>2.0 eV).通过XRD测量计算出薄膜<111>、<220>和<311>三个晶向上的晶粒大小分别为15 nm、17 nm和21 nm;通过Raman测量,计算出其晶化率为35%左右.实验中,将P型纳米硅薄膜与氧化铟锡一起构成有机电致发光器件的复合阳极,研究了他们的发光特性,结果表明:由于P nc Si∶H薄膜材料具有近似半反半透的光学特性,它与高反射率的阴极Al使有机电致发光器件产生了微腔效应,使其发光光谱窄化,半宽高由126 nm窄化到33 nm;发光光亮明显增强,最大亮度为47 130 cd/m2,最大发光效率为9.543 83 cd/A,与以ITO为阴极的无腔器件相比,提高了约127%. 相似文献
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Impurity centres in high purity silicon with ionization energies 38.32 and 40.09meV are observed by photothermal ionization spectroscopy measurements. Their typical shallow donor characteristics are approved by good agreement with theoretic evaluation under varying magnetic fields. The 2p0 state lifetime of one donor centres are more than 3 times longer than that of phosphorus in the same silicon sample. Compared to phosphorus which has been already successfully exploited to produce silicon-based THz radiations, this shallow donor centre has a pronounced enhancement on lifetime and quality factor of population inversion level. Hence, silicon with this donor centre would be a potential excellent candidate to develop improved silicon-based THz sources. 相似文献
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We propose to use four-wave mixing inside silicon waveguides for generating quantum-correlated photon pairs in a single spatial mode. Such silicon-based photon sources not only exhibit high pair correlation but also have high spectral brightness. As the proposed scheme is based on mature silicon technology, it has the potential of becoming a cost-effective platform for on-chip quantum information processing applications. 相似文献
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石墨烯是一种由单层碳原子紧密排列而形成的具有蜂窝状结构的二维晶体材料,特殊的结构赋予了其优异的性能,如高载流子迁移率、电导率、热导率、力学强度以及量子反常霍尔效应.由于石墨烯优异的特性,迅速激起了人们对石墨烯研究以及应用的热情.石墨烯沉积或转移到硅片后,其器件构建与集成和传统硅基半导体工艺兼容.基于石墨烯的硅基器件与硅基器件的有机结合,可以大幅度提高半导体器件的综合性能.随着石墨烯制备工艺和转移技术的优化,硅基底石墨烯器件将呈现出潜在的、巨大的实际应用价值.随着器件尺寸的纳米化,器件的发热、能耗等问题成为硅基器件与集成发展面临的瓶颈问题,石墨烯的出现为解决这些问题提供了一种可能的解决方案.本文综述了石墨烯作为场效应晶体管研究的进展,为解决石墨烯带隙为零、影响器件开关比的问题,采用了量子限域法、化学掺杂法、外加电场调节法和引入应力法.在光电器件研究方面,石墨烯可以均匀吸收所有频率的光,其光电性能也受到了广泛的关注,如光电探测器、光电调制器、太阳能电池等.同时,石墨烯作为典型的二维材料,其优越的电学性能以及超高的比表面积,使其作为高灵敏度传感器的研究成为纳米科学研究的前沿和热点领域. 相似文献
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Group-IV nanocluster formation by ion-beam synthesis 总被引:1,自引:0,他引:1
W. Skorupa L. Rebohle T. Gebel 《Applied Physics A: Materials Science & Processing》2003,76(7):1049-1059
A short review of our investigations devoted to the use of ion-beam-synthesized nanoclusters for silicon-based light emission
and nonvolatile memory effects is presented. Blue-violet light emission is demonstrated based on Ge-implanted silicon dioxide
layers thermally grown on silicon substrates. This version of silicon-based light emission relies on Ge-related defects in
the amorphous ≡Si–O–Si≡ network. The photoluminescence and electroluminescence are excited by a singlet S0–S1 transition of a neutral oxygen vacancy and by electron injection from the silicon substrate into the silicon dioxide layer,
respectively. Whereas the photoluminescence excitation is a well-known mechanism, for the case of electroluminescence an interpretation
was performed for the first time in the course of our studies. It was found that the most probable way to excite luminescence
centers is the impact excitation by hot electrons. Whereas the injection is explained by trap-assisted tunneling of electrons
from the substrate into the oxide, the electrons will be transported via traps or in the SiO2 conduction band. The application of the silicon-based light-emitting devices for an integrated optocoupler arrangement is
described. Another application of nanoclusters is based on the investigation of thin Si-implanted silicon dioxide layers for
nonvolatile memory devices. First promising results demonstrate that the observed programming window can reach several volts
and the devices exhibit excellent retention behavior. A 256 K-nv-SRAM is demonstrated showing a programming window of >1 V
for write pulses of 12 V/8 ms.
Received: 21 August 2002 / Accepted: 21 August 2002 / Published online: 12 February 2003
RID="*"
ID="*"Corresponding author. Fax: +49-351/260-3411, E-mail: w.skorupa@fz-rossendorf.de 相似文献
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The field of silicon nanowires (SiNWs) and silicon-based 1D nanostructured heterostructures represent one of the most important research subjects within the nanomaterials family. A series of synthesis approaches of SiNWs and silicon-based 1D nanostructured heterostructures have been developed, and have garnered the greatest attention in the past decades for a variety of applications. This article provides an overview on recent research on the synthesis, properties and applications of SiNWs, silicon nanotubes (SiNTs) and complex silicon-based 1D nanostructures. 相似文献
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Free-carrier absorption (FCA) has proven to be an important obstacle in the development of a silicon-based laser; however, FCA may serve as a potential advantage in active silicon-based switches or modulators. In this work, we present FCA modulation in slot waveguides with silicon nanocrystals (Si-ncs) embedded in SiO(2) as the low-index slot material. Slot waveguides were fabricated with and without Si-ncs, and the presence of Si-ncs was shown to increase the pump-induced FCA loss in the waveguides by a factor of 4.5. We modeled the Si-nc material using a four-level rate equation analysis to estimate the excited population of Si-ncs, allowing us to extract a value of 2.6 × 10(-17) cm(2) for the FCA cross section of the Si-nc material. 相似文献
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Ricardo Claps Dimitrios Dimitropoulos Bahram Jalali Bernard Jusserand 《Superlattices and Microstructures》2006,39(6):501-516
This paper discusses the design of acoustic vibrational modes in Si/Ge planar optical waveguides and its application in creating silicon-based Raman devices with a flexible spectrum. It addresses the deficiencies of the recently demonstrated Raman-based silicon lasers and amplifiers as they relate to spectral and low efficiency limitations of bulk silicon. The treatment is for in-plane scattering in a forward scattering configuration. In addition to calculating the spectrum and the efficiency for Raman active modes, it is shown that the negligible wave-vector of the phonons involved in this type of scattering allows for the use of the bandgap “pinching” effect to arrive at specific layer thicknesses for Si and Ge that optimize the scattering efficiency. 相似文献
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C. Jamois R. B. Wehrspohn L. C. Andreani C. Hermann O. Hess U. Gsele 《Photonics and Nanostructures》2003,1(1):1-13
A review of the properties of silicon-based two-dimensional (2D) photonic crystals is given, essentially infinite 2D photonic crystals made from macroporous silicon and photonic crystal slabs based on silicon-on-insulator basis. We discuss the bulk photonic crystal properties with particular attention to the light cone and its impact on the band structure. The application for wave guiding is discussed for both material systems, and compared to classical waveguides based on index-guiding. Losses of resonant waveguide modes above the light line are discussed in detail. 相似文献