共查询到20条相似文献,搜索用时 93 毫秒
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分别在550和800℃对CVT方法生长的非掺ZnO单晶进行闭管磷扩散. 通过Hall测试、X射线光电子谱(XPS) 、光致发光(PL)以及喇曼散射对扩散后的样品进行测试分析. 发现扩散掺杂后的ZnO单晶仍显示n型导电性,自由电子浓度比非掺样品增高,在800℃扩散后尤为明显. PL测试结果表明,掺杂样品在420~550nm范围的可见光发射与缺陷有关. XPS测试表明:在550℃掺杂,P原子更易代替Zn位;在800℃扩散时,P未占据Zn位,而似乎占据了O位. 最终在磷扩散后的ZnO单晶中形成了高浓度的浅施主缺陷,造成了自由电子的显著增加. 相似文献
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分别在550和800℃对CVT方法生长的非掺ZnO单品进行闭管磷扩散.通过Hall测试、X射线光电子谱(XPS)、光致发光(PL)以及喇曼散射对扩散后的样品进行测试分析.发现扩散掺杂后的ZnO单晶仍显示n型导电性,自由电子浓度比非掺样品增高,在800℃扩散后尤为明显.PL测试结果表明,掺杂样品在420~550nm范围的可见光发射与缺陷有关.XPS测试表明:在550℃掺杂,P原子更易代替Zn位;在800℃扩散时,P未占据Zn位,而似乎占据了O位.最终在磷扩散后的ZnO单晶中形成了高浓度的浅施主缺陷,造成了自由电子的显著增加. 相似文献
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MOCVD生长P型GaN的掺Mg量的研究 总被引:1,自引:0,他引:1
使用 MOCVD技术在 Al2 O3衬底上生长了 Ga N∶ Mg薄膜 .通过对退火后样品的光电性能综合分析 ,研究了掺 Mg量对生长 P型 Ga N的影响 .结果表明 :要获得高空穴载流子浓度的 P型 Ga N,Mg的掺杂量必须控制好 .掺 Mg量较小时 ,Ga N∶ Mg单晶膜呈现 N型导电 ,得不到 P型层 ;掺 Mg量过大时 ,会形成与 Mg有关的深施主 ,由于深施主的补偿作用 ,得不到高空穴浓度的 P型 Ga N.生长 P型 Ga N的最佳 Cp2 Mg/TMGa之比在 1 /660— 1 /330之间 相似文献
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采用Zn3N2热氧化法在直流磁控溅射设备上制备了掺氮ZnO薄膜(ZnO:N),研究了不同退火温度对样品结构和光电特性的影响.X射线衍射谱(XRD)结果表明,Zn3N2在600℃以上退火即可转变为ZnO:N薄膜.X射线光电子能谱(XPS)发现,在热氧化法制备的ZnO:N薄膜中,存在两种与N相关的结构,分别是N原子替代O(受主)和N2分子替代O(施主),这两种结构分别于不同的退火温度下存在,并且700℃下退火的样品在理论上具有最高的空穴浓度,这一点也由霍尔测量结果得到证实.同时,从低温PL光谱中观察到了与No受主有关的导带到受主(FA)和施主-受主对(DAP)的跃迁,并由此计算出热氧化法制备的ZnO:N薄膜中的No受主能级位置. 相似文献
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在用SEM观察沿单晶生长方向切割掺V SiC晶片时,发现其二次电子像存在衬度。表现为先生长部分较明亮,后生长部分较暗淡,中间存在明显突变。在用PVT生长掺V SiC单晶时,SiC单晶中同时含有浅施主N和深受主杂质V是补偿半导体。从补偿半导体载流子浓度计算出发,建立了二次电子像衬度与载流子浓度的对应关系,很好解释了这一实验现象。结果表明,SiC单晶生长过程中随着浅施主N的减少,n型载流子的浓度逐步减少;当其浓度与V相当时,载流子浓度突变,可瞬间减少10个量级,此后又缓慢减少。正是这种载流子的突变引发了扫描电镜二次电子像衬度。 相似文献
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Michael Reilly 《半导体技术》2004,29(12)
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
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Thomas M.Trexler 《半导体技术》2004,29(5)
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
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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
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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
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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
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GU Min-fen LIANG Zhong-cheng WANG Ren-zhou DONG Xiang-mei ZHANG Pei-ming CHEN Jia-bi 《光电子快报》2008,4(2):150-152
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
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Qi-jiang Ran Pei-de Han Yu-jun Quan Li-peng Gao Fan-ping Zeng Chun-hua Zhao 《光电子快报》2008,4(4):239-242
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
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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
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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
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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