Ultraviolet photodetectors have attracted significant research attention in recent years due to their potential applications in civilian and military fields. ZnO nanowires and nanorods have been regarded as the most potential candidates for ultraviolet photodetectors fabrication because of their peculiar characteristics and size effect, which are different from their bulk material. Recently, many novel routes and semiconductor features, such as the surface and interface engineering, the pryo-phototronic effect, the piezo-phototronic effect, the surface plasmon effect and the surface functionalization have been utilized to improve the photoelectric characteristics of ultraviolet photodetectors. Thus, the working mechanism of these effects existing in ZnO nanowires/nanorods-based ultraviolet photodetectors should be investigated in-depth. In this paper, firstly, the hydrothermal method and the chemical vapor deposition method, as two typical synthesis methods of ZnO nanowires are briefly reviewed. Secondly, we focus on reviewing the properties of varied ZnO nanowires/nanorods-based ultraviolet photodetectors constructed using the above mentioned semiconductor features with metal-semiconductor-metal structure, Schottky barrier structure, vertical p-n heterojunction structure and core-shell heterostructure. Furthermore, the most attractive self-powered ultraviolet photodetectors are systematically reviewed. For various ZnO nanowires/nanorods-based ultraviolet photodetectors, we put the emphasis on the working mechanism of semiconductor features to improve the properties of the photodetectors. Finally, we give an outlook on the future development of ZnO nanowires/nanorods-based ultraviolet photodetectors.

The effects of the synergy of pressure regulation and Eu substitution on the microstructure and thermoelectric (TE) properties are investigated for type-I clathrates Eu[Formula: see text]Ba[Formula: see text]Cu 6 Si[Formula: see text]Ge[Formula: see text] ([Formula: see text], 0.5, 1, 1.5). The rare-earth-substituted and high-pressure modulated samples show complicated morphologies composed of abundant grains and rich in lattice defects. The Seebeck coefficient and the electrical conductivity of the rare-earth-substituted samples synthesized by HPHT method are consistent with [Formula: see text]-type conduction and metal-like behavior. The carrier concentration increases and the Hall carrier mobility decreases with increasing Eu substitution at room temperature. Although the increase of Eu filling rate decreased the Seebeck coefficient of the samples, it increased the power factor (PF) of the samples significantly. The thermal conductivity also reduced on account of Eu filling. As a result, a minimum [Formula: see text] value (0.67 Wm[Formula: see text]K[Formula: see text]) and a relatively higher zT value (0.68) are achieved. Compared to the Eu-free sample, the achieved zT value of the Eu-substituted sample is a [Formula: see text][Formula: see text]62% enhancement. So, high-pressure technique is an effective route to synthesize clathrate materials and optimize TE properties simultaneously.

Type-I clathrate compounds Yb x Ba8-x Ga16Ge30 have been synthesized by the high-pressure and high-temperature (HPHT) method rapidly. The effects of the synergy of atom filling and pressure regulation on the microstructure and thermal and electrical properties have been investigated. With the content of Yb atom increasing, the carrier concentration is improved, the electrical resistivity and the absolute Seebeck coefficient are decreased, while the thermal conductivity is reduced significantly. A series of extremely low lattice thermal conductivities are achieved, attributed to the enhancement of multiscale phonon scattering for the "rattling" of the filled guest atoms, the heterogeneous distribution of nano- and microstructures, grain boundaries, abundant lattice distortions, lattice deformations, and dislocations. As a result, a maximum ZT of about 1.07 at 873 K has achieved for the Yb0.5Ba7.5Ga16Ge30 sample.

Si-based clathrate thermoelectric (TE) materials composed of low-cost, nontoxic, lightweight, and earth-abundant elements are typical representatives of cheaper thermoelectric materials. However, synthesis is difficult, and the relatively low ZT values are the barriers hindering the further development of the silicon clathrates. So, it is necessary to explore an alternative synthetic method and improve the ZT values simultaneously. In this work, Si-based clathrate Ba8Cu6Si40 samples have been synthesized by a simple, rapid, and feasible HPHT method with 25 min. We have investigated the changes of the TE properties and microstructures depending on the pressure in detail. The power factor has been increased due to the decreased carrier concentration, meanwhile, the thermal conductivity has been cut down on account of the strengthened full-spectrum-phonons scattering resulting from the multiple and multiscale microstructures by high-pressure processing. Ultimately, a relatively good ZT value 0.31 is achieved at 773 K for the sample synthesized at 4 GPa. To the best of our knowledge, it is higher than all of the results of pure Si-based Ba8Cu6Si40 compounds formed by other methods.

With the rise of nanoscience and nanotechnologies, especially the continuous deepening of research on low-dimensional materials and structures, various kinds of light-emitting devices based on nanometer-structured materials are gradually becoming the natural candidates for the next generation of advanced optoelectronic devices with improved performance through engineering their interface/surface properties. As dimensions of light-emitting devices are scaled down to the nanoscale, the plentitude of their surface/interface properties is one of the key factors for their dominating device performance. In this paper, firstly, the generation, classification, and influence of surface/interface states on nanometer optical devices will be given theoretically. Secondly, the relationship between the surface/interface properties and light-emitting diode device performance will be investigated, and the related physical mechanisms will be revealed by introducing classic examples. Especially, how to improve the performance of light-emitting diodes by using factors such as the surface/interface purification, quantum dots (QDs)-emitting layer, surface ligands, optimization of device architecture, and so on will be summarized. Finally, we explore the main influencing actors of research breakthroughs related to the surface/interface properties on the current and future applications for nanostructured light-emitting devices.

Perovskite photovoltaic materials (PPMs) have emerged as one of superstar object for applications in photovoltaics due to their excellent properties—such as band-gap tunability, high carrier mobility, high optical gain, astrong nonlinear response—as well as simplicity of their integration with other types of optical and electronic structures. Meanwhile, PPMS and their constructed devices still present many challenges, such as stability, repeatability, and large area fabrication methods and so on. The key issue is: how can PPMs be prepared using an effective way which most of the readers care about. Chemical vapor deposition (CVD) technology with high efficiency, controllability, and repeatability has been regarded as a cost-effective road for fabricating high quality perovskites. This paper provides an overview of the recent progress in the synthesis and application of various PPMs via the CVD method. We mainly summarize the influence of different CVD technologies and important experimental parameters (temperature, pressure, growth environment, etc.) on the stabilization, structural design, and performance optimization of PPMS and devices. Furthermore, current challenges in the synthesis and application of PPMS using the CVD method are highlighted with suggested areas for future research.

采用热化学气相沉积的方法首先合成了SiC纳米颗粒.接着,用扫描电子显微镜、透射电子显微镜、拉曼光谱、X射线电子能谱和X射线衍射谱等表征了材料的结构和组成.最后,利用光致发光谱和光致发光谱微区成像系统研究了材料的光学性质.实验结果表明,制备的纳米材料的尺寸约为70～90 nm;发光带由中心波长分别为530和542 nm的绿光发光峰组成,分析认为分别来自于SiC材料本身和表面缺陷;在相同的激发光强度下,材料最大发光强度相对于相同条件下合成的体材料提高5倍左右.制备的SiC纳米材料在绿光光电子器件领域有着潜在的应用价值.

Using two-step growth method and buffer layer annealing treatment, the double heterojunction structures of In0.82Ga0.18As epilayer capped with InAs0.6P0.4 layer were prepared on InP substrate by low pressure metal organic chemical vapor deposition (LP-MOCVD). Based on the high quality In0.82Ga0.18As structures, the In0.82Ga0.18As PIN photodetector with cut-off wavelength of 2.56 μm at room temperature was fabricated by planar semiconductor technology, and the device performance was investigated in detail. The typical dark current at the reverse bias V R=10 mV and the resistance area product R 0 A are 5.02 μA and 0.29 Ω·cm2 at 296 K and 5.98 nA and 405.2 Ω·cm2 at 116 K, respectively. The calculated peak detectivities of the In0.82Ga0.18As photodetector are 1.21×1010 cm·Hz1/2/W at 296 K and 4.39×1011 cm·Hz1/2/W at 116 K respectively, where the quantum efficiency η=0.7 at peak wavelength is supposed. The results show that the detection performance of In0.82Ga0.18As prepared by two-step growth method can be improved greatly.

基于双通道表面等离子共振(surface plasmon resonance,SPR)传感器,结合不同粒径的金纳米粒子(Aunanoparticle,AuNPs)标记多克隆抗体(polyclonal antibody,PAb)作为第二抗体,采用氨基偶联的方法将PAb固定在传感器表面作为第一抗体,采用三明治夹心法进行了检测大肠杆菌O157∶H7 (E.coli O157∶H7)的研究.考察3种粒径的AuNPs作为标记物,增强SPR响应信号检测E coli O157∶H7的能力.结果表明,增强效果最佳的AuNPs粒径为17.79 nm,其可检测到的E coli O157∶H7的最低浓度为10 CFU/mL.

SiC/SiO2 core–shell nanowires were synthesized on Si (100) substrate by the reaction of methane with silicon dioxide using iron as catalyst. Structural properties of the nanowires were characterized by Scanning electron microscopy, Transmission electron microscopy and X-ray diffraction. The light-emitting properties of nanowires were studied by photoluminescence spectroscopy. A sharp ultraviolet peak at 380 nm and an intensive broad green band with defined maximum peak at 505 nm were observed in spectra of as-grown nanowires. In addition, the emission intensity of ultraviolet peak decreased gradually until disappeared, but the green band emission intensity increased gradually when nanowires further annealed with different durations in oxygen and argon mixed gas atmosphere. The change of emission intensity could be attributed to different origins of photoluminescence peak: the ultraviolet peak originated from the oxygen-vacancy defects in the SiO2 shell and the green band that came from the SiC cores caused by quantum confinement effect.

4H-SiC/SiO 2 nanowires are synthesized and the temperature-dependent photoluminescence (PL) properties of the nanowires are studied. Their structure and chemical composition are studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Raman spectra. At room temperature, an ultraviolet PL peak and a green PL band are observed. From the PL spectrum measured in the temperature range from 80 K to 300 K, the free excition emission, donor bound excition emission and their multiple-phonon replicas have been observed in ultraviolet region, and their origins have been identified. Moreover, it has been found that the temperature dependence of the free exciton peak position can be described by standard expression, and the thermal activation energy values extracted from the temperature dependence of the free exciton and bound exciton peak integral intensity are about 40 meV and 181 meV, respectively.

Due to the indirect band gap structure, the light emission efficiency of SiC materials is usually very low, which limits the applications of SiC in optoelectronic devices. A lot of methods have been employed to improve the light emission efficiency of SiC materials, of which synthesizing SiC nano-structure materials would be an effective way. In our work, SiC/SiO2 core-shell nanowires were synthesized on Si (100) substrate by the reaction of methane with silicon dioxide using iron as catalyst. The structural properties of the nanowires are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). It can be seen that the nanowires have a diameter about 50 nm and length about 10 m, and the nanowires consist of a 30 nm single-crystal -SiC core and a 10 nm amorphous SiO2 shell. The light-emitting properties of nanowires are studied by photoluminescence spectroscopy. A sharp ultraviolet peak at 380 nm and an intensive broad green band with defined maximum peak at 505 nm are observed in PL spectra of as-grown nanowires. According to analysis, the ultraviolet peak originates from the oxygen-vacancy defects in the SiO2 shell and the broad green band comes from the SiC cores caused by quantum confinement effect.

InAs 0.6 P 0.4 epilayers grown by low-pressure metal organic chemical vapor deposition (LP-MOCVD) on InP (100) substrate are investigated. The influence of growth temperature on crystalline quality of InAs 0.6 P 0.4 epilayer is characterized by scanning electron microscopy (SEM), Hall measurements, photoluminescence (PL) spectra, and the Raman properties are analyzed by Raman scattering spectrum. The characterization results show that the crystalline quality and Raman property of InAs 0.6 P 0.4 epilayers have close relation to the growth temperature. It indicates that 530 °C is the optimum growth temperature to get good quality and properties of InAs 0.6 P 0.4 epilayers.

以甲烷和二氧化硅纳米球为源,铁作催化剂,成功制备了长径比达200的碳化硅/二氧化硅核壳结构一维纳米线,分析了纳米线的合成机制,并研究了纳米线的场发射特性.研究结果表明,当施加的电场为5.5 V/μm时,纳米线的场发射电流密度可达0.41 mA/cm2,显示出良好的场发射特性.通过分析实验结果,认为纳米线具有良好场发射特性的原因有2个:一个是核壳结构纳米线的长径比比较大;另一个是核壳结构纳米线表面包覆的低电子亲和势的二氧化硅薄层抑制了表面缺陷发射.

A simple and effective method is developed to controllably synthesize branching silicon carbide (SiC) nanowires by using gas flow fluctuation. The experimental results indicated that uniformly 'Y' shaped branching SiC nanowires were successfully synthesized. A branching mechanism of fluctuation-promoted split of catalyst particles is proposed. The synthetic approach presented here will open a new route to fabricate other nanomaterials branching structure. Photoluminescence (PL) spectrum and mapping result show that the nanowires can emit green band centered at 2.32eV (535nm) at room temperature, indicating potential applications in integrated nano–optoelectronic devices.

In0.82Ga0.18As epilayers were grown by LP-MOCVD on InP substrates with the insertion of In0.82Ga0.18As buffer layers, which were annealed at various temperatures between 490 degrees C and 630 degrees C for 5 min in AsH3 ambient. The effect of buffer layer annealing temperatures on the crystalline quality of In0.82Ga0.18As epilayers was investigated by atomic force microscopy, scanning electron microscopy, double-crystal X-ray diffraction, and room-temperature Hall measurement. The characterization results showed that high quality In0.82Ga0.18As epilayers were obtained by optimizing the annealing temperatures of buffer layers. In particular, the In0.82Ga0.18As epilayer with buffer layer annealed at 530 degrees C showed the best crystalline quality. The changes of crystalline quality of In0.82Ga0.18As epilayers at high and low annealing temperature can be attributed to the recrystallization and reevaporation of the In0.82Ga0.18As buffer layers. (C) 2011 Elsevier B.V. All rights reserved.

In0.82Ga0.18As epilayers were grown on InP substrates using a two-step growth technique by LP-MOCVD. A homogeneous low-temperature (450°C) In0.82Ga0.18As buffer layer was introduced to improve the crystalline quality of epilayers. The influence of low-temperature buffer layer deposition condition, such as thermal annealing duration, on the crystalline quality of the In0.82Ga0.18As epilayer was investigated. Double-crystal X-ray diffraction measurement, Hall measurement, and Raman scattering spectrum were used to evaluate the In0.82Ga0.18As epilayers. Atomic force microscope was used to study the surface morphology. It is found that the In0.82Ga0.18As epilayer, with buffer layer thermal annealing for 5min, exhibits the best crystalline quality. The change of the surface morphology of the buffer layer after thermal annealing treatment was suggested to explain the phenomenon.

Novel ordered aloetic-shaped SiC nanowires were synthesized on a Si (100) substrate by reacting methane with silicon dioxide using iron as a catalyst. Their structure and chemical composition were studied by scanning electron microscopy (SEM), X-ray diffraction (XRD), and transmission electron microscopy (TEM). The wires have a tapered aloetic structure with a top diameter about 50-80 nm and a length about 10 microm. The field emission properties of the aloetic nanowires were investigated. A stable emission with current density of 0.525 mA/cm2 at an applied electric field of 2.2 V/microm and a low turn-on electric fields of 1.4 V/microm were observed. The excellent field emission properties indicate that the aloetic-shaped SiC nanowires may have potential applications in flat panel displays and electron field-emitting devices.

InAs 0.6 P 0.4 epilayers grown by low-pressure metalorganic chemical vapor deposition (LP-MOCVD) on InP (1 0 0) substrates were investigated. A two-step growth method, in which low-temperature (450 °C) InAs 0.6 P 0.4 buffer layers were introduced into the structure, was employed to relax the mismatch between the InAs 0.6 P 0.4 and InP substrate. The effect of epilayer's growth temperature on crystalline quality of InAs 0.6 P 0.4 epilayer was studied by X-ray diffraction, scanning electron microscopy, Hall measurements, and photoluminescence spectrum. The characterization results showed that the growth temperature is an important factor for obtaining good quality and property of InAs 0.6 P 0.4 epilayers and 530 °C is the optimum epilayer's growth temperature in our experimental conditions. Keywords InAs 0.6 P 0.4 MOCVD Two-step growth method Epilayer's growth temperature 1 Introduction InAs x P 1− x alloys show excellent promise due to the wide range of attainable band-gap energies from 0.36 eV to 1.35 eV in the application of optical devices such as the photodiodes [1] , avalanche photodiodes for detection in the range 1.6–2.5 μm [2] , the laser diodes used in 1.3 μm [3] , the quantum dot lasers with the wavelength tuned to 1.55 μm [4] , high electron drift velocity devices, and the quantum well modulators [5] . However, in InAs x P 1− x /InP heteroepitaxy, using dissimilar materials may lead to poor structures and degrade the electrical and optical properties of the materials. The problem can be reduced by growth of buffer layers with or without graded lattice parameters. A step-graded buffer layers in composition is often used to inhibit the dislocations to propagate towards the active layer of InAs x P 1− x materials [6] . But a single approach can simplify the growth procedure, such as the two-step growth method. It has been adopted to grow high mismatch epilayers, in which the low-temperature growth of thin buffer layer is followed by annealing and then growth of thick epilayer at higher temperatures [7] . The low-temperature buffer layer is believed to act as a template for succeeding high-temperature grown epilayers and to accommodate lattice strain caused by both lattice mismatch and thermal one. SiGe, AlGaN, InAs and GaN with two-step growth method [8–11] have been studied. However, InAs 0.6 P 0.4 epilayers grown on InP substrate with this growth method is rarely reported. In this paper, we report LP-MOCVD growth of InAs 0.6 P 0.4 epilayers on InP (1 0 0) substrates with two-step growth method and investigate the effect of epilayer's growth temperature on crystalline quality of InAs 0.6 P 0.4 epilayers. The X-ray diffraction (XRD), scanning electron microscopy (SEM), Hall measurement and photoluminescence (PL) spectrum are used to evaluate the property of materials. 2 Experimental Experiments were carried out in a horizontal reactor by LP-MOCVD. All the samples were grown on semi-insulating InP (1 0 0) substrates at a pressure of 70 Torr. Palladium-diffused hydrogen was used for carrier gas at a total flow of 2.0 L/min. The substrates were heated by inductively coupling RF power and temperatures were detected by a thermocouple. The growth was performed using trimethylindium (TMIn), arsine (PH 3 ) and arsine (AsH 3 ) diluted to 10% in H 2 as precursors. The two-step growth process can be described as follows. At first, an InAs 0.6 P 0.4 buffer layer of 200 nm was grown on InP substrates at 450 °C to relax the mismatch between the InAs 0.6 P 0.4 and InP substrate. Then, the deposition of InAs 0.6 P 0.4 epilayer was followed after the temperature rises from 450 °C to the InAs 0.6 P 0.4 epilayer's growth temperature. In our experiments, the epilayer's growth temperature was selected from 500 °C to 580 °C, and the thickness was fixed 1 μm. The epilayers with growth temperatures of 500 °C, 530 °C, 550 °C, and 580 °C were named as samples (A), (B), (C), and (D), respectively. 3 Results and discussions The crystalline quality of InAs 0.6 P 0.4 epilayers with different epilayer's growth temperatures were studied by XRD measurement. Fig. 1 shows the XRD results of the samples (A), (B), (C), and (D). The alloy composition was estimated from XRD peak position of the alloy using Vegard's law [12] , which is displayed in inset of Fig. 1 . For samples (A), (B), (C), and (D), the full width at half maximum (FWHM) of XRD is 448 s, 336 s, 550 s, and 686 s, respectively. It is clear that the FWHM of sample (B) is the smallest of the four samples and indicates the crystalline quality of the sample (B) is optimum. In our experiments, the growth parameters such as the thicknesses of buffer layer and epilayers, the As content, and the reactor pressure are identical of the four samples except for the epilayer's growth temperature. It is reasonable to speculate that the change of the FWHM of the XRD of InAs 0.6 P 0.4 epilayer is related to the epilayer's growth temperature. It is found that the selection of growth temperature is important to improve the crystalline quality of InAs 0.6 P 0.4 epilayers. SEM is used to study the surface morphology of the samples. The surface morphology of samples (A), (B), (C), and (D) is shown in Fig. 2 . In Fig. 2 (A), the surface corrugations that form weak cross-hatched patterns are visible. In Fig. 2 (B), the cross-hatched patterns disappear and the surface becomes flat and smooth. The surface morphology is improved. The surface morphology in Fig. 2 (C), is similar to that of Fig. 2 (B), but some pyramid-like pits appear in the smooth surface. In Fig. 2 (D), a grainy surface with some pits defects is developed. This indicates that 3-dimensional (3D) growth mode takes place. It is evident that the surface morphology of sample (B) is better than those of samples (A), (C), and (D). The improvement of surface morphology indicates that the epilayer's growth temperature is optimized. It is known that growth temperature can provide migration power for the surface atoms in the surface-diffusion process during growth and play an important role in the transition of growth mode. When the growth temperature decreases, surface atoms diffusion is restricted and the 3D growth mode is delayed. Therefore, when the epilayer was grown at 500 °C, lower than the optimum temperature, the surface atom migration and nucleation or motion of dislocations in the epilayers was restricted, the corrugations were formed and then cross-hatched patterns appeared [13,14] . However, when the growth temperature increased to 530 °C, the surface was flat and smooth. The morphology is improved greatly. When the growth temperatures were higher than 530 °C, such as 550 °C and 580 °C, the surface atom had so much energy to migrate that the 3D growth enhanced and the residual strain was relaxed by introduction of misfit dislocations as the appearance of the pyramid-like pits. The surface morphology was degraded. This indicates that the growing of InAs 0.6 P 0.4 with two-step growth method at an appropriate growth temperature is essential in improving the surface morphology of its epilayers. Hall measurements are used to further characterize the crystalline quality of InAs 0.6 P 0.4 epilayers. Room temperature electron property of the InAs 0.6 P 0.4 epilayers is measured with magnetic field of 2100 G. The results of Hall measurements are shown in Fig. 3 . The carrier concentration of samples changes from 1.25 × 10 16 cm −3 to 5.72 × 10 16 cm −3 with the growth temperature rising from 500 °C to 580 °C, and it has lowest value at 530 °C. On the other hand, the mobility of samples increases from 3998 cm 2 /Vs to 4697 cm 2 /Vs with increasing the growth temperature from 500 °C to 530 °C, and it decreases from 4697 cm 2 /Vs to 3342 cm 2 /Vs with rising the growth temperature from 530 °C to 580 °C. It is clear that sample (B) has the lowest carrier concentration and highest electron mobility. It is obvious that the changes of carrier concentration and mobility are related to epilayer's growth temperature. In the epilayers, the residual misfit dislocations in epilayers act as scattering centers and reduce the carrier mobility [15,16] . Defects of the InAs 0.6 P 0.4 epilayer are decreased by optimizing the epilayer's growth temperatures. Hereby, the density of misfit dislocations in the epilayer of sample (B) is the least. PL spectrum is another useful way to characterize the crystalline quality of InAs 0.6 P 0.4 epilayers. Fig. 4 shows the PL spectrum of the four samples measured at 77 K. The band-gap energy of the samples is about 0.7944 eV that is consistent with the value of 0.7952 eV calculated with the formula E g = 1.407 − 1.073 x + 0.089 x 2 in [17] . The FWHM of PL is 27.5 meV, 24.5 meV, 30.2 meV, and 31.7 meV, as shown in Fig. 5 , corresponding to samples (A), (B), (C), and (D), respectively. For sample (B), the FWHM of PL is the minimum. Generally, luminescent efficiency for the band edge emission increases when the purity of the crystal increases. Some defects such as misfit dislocations are known to quench luminescence due to nonradiative recombination as well as to broaden photoluminescence linewidths. So the change of the FWHM of PL is related to the growth temperatures of the epilayers. The PL results also indicate that sample (B) grown at 530 °C has better crystalline quality. 4 Conclusions In summary, InAs 0.6 P 0.4 epilayers with different growth temperatures were grown on InP substrate by LP-MOCVD with two-step growth method. The crystalline quality of the samples was characterized using the XRD, SEM, the room temperature Hall measurement and PL spectrum. The experimental results show that the crystalline quality could be improved by employing an appropriate epilayer's growth temperature. In particular, the epilayer's quality is optimum when the growth temperature of the epilayer is 530 °C. Our work shows a simple way on how to design for the suitable epilayer in the heteroepitaxy of InAs x P 1− x on InP substrate. Acknowledgments This work was supported by the Projects of National Natural Science Foundation of China under Grant Nos. 50632060 and 50372067 . References [1] C.A. Tran R.A. Masut J.L. Brenbner R. Leonelli J. Cryst. Growth 124 1992 596 603 [2] C.A. Wang E.K. Duerr J.P. Donnelly D.R. Calawa D.C. Chapman J. Cryst. Growth 310 2008 1583 1589 [3] Y. Imajo A. Kasukawa T. Namegaya T. Kikuta Appl. Phys. Lett. 61 1992 2506 2508 [4] A. Michon R. Hostein G. Patriarche N. Gogneau G. Beaudoin A. Beveratos I.R. Philip S. Laurent S. Sauvage P. Boucaud I. Sagnes J. Appl. Phys. 104 2008 043504 [5] R.Y.F. Yip A.A. Ouali A. Bensaada P. Desjardins M. Beaudoin L. Isnard J.L. Brebner J.F. Currie R.A. Masut J. Appl. Phys. 84 1997 1905 1915 [6] M.K. Hudait Y. Lin S.A. Ringel Appl. Phys. Lett. 82 2003 3212 3214 [7] H.J. Ko Y.F. Chen J.M. Ko T. Hanada Z. Zhu T. Fukuda T. Yao J. Cryst. Growth 207 1999 87 94 [8] H. Chen L.W. Guo Q. Cui Q. Hu Q. Huang J.M. Zhou J. Appl. Phys. 79 1996 1167 1169 [9] C.F. Shih N.C. Chen S.Y. Lin K.S. Liu Appl. Phys. Lett. 86 2005 211103 211105 [10] H. Yuan S.J. Chua Z. Miao J. Dong Y. Wang J. Cryst. Growth 273 2004 63 67 [11] I. Akasaki J. Cryst. Growth 237–239 2002 905 911 [12] R.L. Moon J. Electr. Mater. 3 1974 635 644 [13] K.H. Huang B.W. Wessels J. Cryst. Growth 92 1988 547 552 [14] W.M. Zhang C.Y. Yi A. Brown J. Vac. Sci. Technol. B 43 2007 960 963 [15] M.K. Hudait Y. Lin C.L. Andre P.M. Sinha S.A. Ringel Mat. Res. Soc. Symp. Proc. 722 2002 K10.2.1-K10.2.6 [16] V.W.L. Chin J. Phys. Chem. Solids 53 1992 897 904 [17] M. Wada S. Araki T. Kudou T. Umezawa S. Nakajima T. Ueda Appl. Phys. Lett. 76 2000 2722 2724

碳纳米管（CNT）和衬底的电学接触问题是获得高性能CNT电子器件的一个关键性的问题。本文采用电泳电镀方法制备CNT冷阴极,有效改善了CNT与衬底间接触电阻,增强了碳纳米管场发射性能。电泳电镀法制备的碳纳米管冷阴极场发射的开启电场（电流密度为10μA.cm-2时的电场）由2.95 V.μm-1降低到1.0V.μm-1,在电场为8V.μm-1时电流密度由0.224增加到0.8112mA.cm-2。在电流密度为800μA.cm-2时进行1h的场发射稳定性测试,结果表明,电泳电镀法所得CNT场发射电子源电流密度几乎不变,而且电流密度比较稳定;而只有电泳的方法获得的CNT场发射电子源电流密度波动较大,电流不稳定且呈较快的衰减趋势,1h后减少到原来的75%。采用电泳电镀方法制备CNT阴极,CNT的根部被纳米银颗粒覆盖和包裹,使CNT与衬底接触更加牢固而紧密,又由于银具有很好的导电性,从而大大减小了接触电阻,因此电泳电镀法能大大改善CNT与衬底的电学接触性能。