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971.
采用磁控溅射的方法在p-GaN上制备了GZO透明导电薄膜,通过在p-GaN和GZO界面之间插入AgOx薄层来改善LED器件的接触性能。研究结果表明:氮气退火后,采用界面插入层的AgOx/GZO薄膜电阻率为5.8×10-4Ω.cm,在可见光的透过率超过80%。AgOx界面插入层有效地降低了GZO与p-GaN之间的接触势垒,表现出良好的欧姆接触特性,同时使LED器件的光电性能获得了显著的提高。在50 mA的注入电流下,相比于常规的GZO电极LED器件,AgOx/GZO电极LED器件的正向电压由9.68 V降至6.92 V,而发光强度提高了13.5%。 相似文献
972.
Spreading of nanofluids on solid substrate was studied via molecular dynamics simulations. Simulation models for two immiscible fluids (oil and water based nanofluids) confined in a slit between two planar solid walls were set up. The influence of the volume concentration of the nanoparticles on the three-phase contact line motion was investigated. We found that the larger volume concentration results in more visible nanoparticle adsorption on solid surface. This effect further induces an advancing displacement of the contact line compared with the meniscus profiles in low concentration case and that with the absence of nanoparticles. These findings are consistent with the previous experimental and theoretical results and provide the atomic-scale understanding on nanofluid spreading. 相似文献
973.
Evaporation of sessile water droplet on polydimethylsiloxane (PDMS) surfaces with three different curing ratios (5:1, 10:1, and 20:1) was experimentally investigated in this paper. We show that the constant contact radius (CCR) evaporation on surface with high curing ratio lasts longer than that with low curing ratio. We also measured Young's moduli of PDMS films by using atomic force microscopy (AFM) and simulated surface deformation of PDMS films induced by sessile water droplet. With increasing curing ratio of PDMS film, Young's modulus of PDMS film is getting lower, and then there will be larger surface deformation and more elastic stored energy. Since such energy acts as a barrier to keep the three-phase contact line pinned, thus it will result in longer CCR evaporation on PDMS surface with higher curing ratio. 相似文献
974.
Research on the electrical characteristics of an organic thin-film field-effect transistor based on alternating-current resistance 下载免费PDF全文
In this article, an organic thin-film field-effect transistor (OTFFET) with top-gate and bottom-contact geometry based on pentacene as the active layer is fabricated. The experimental data of the I-V are obtained from the OTFFET device. The alternating-current (AC) resistance value of the OTFFET device is calculated using the derivation method from the experimental data, and the AC resistance trend curves of the OTFFET device are obtained with the region fitting method. We analyse the characteristics of the OTFFET device with an AC resistance trend curve. To discover whether it has a high resistance, it is proposed to judge the region of the source/drain voltage (VDS) less than the transition voltage, thereby determining whether the contact between the metal electrode and the organic semiconductor layer of the OTFFET device is Ohmic or non-Ohmic. The theoretical analysis shows that the field-effect mobility and the AC resistance are in reverse proportion. Therefore, we point out that reducing AC resistance is necessary if field-effect mobility is to be improved. 相似文献
975.
976.
Typical VOF algorithms rely on an implicit slip that scales with mesh refinement, to allow contact lines to move along no-slip boundaries. As a result, solutions of contact line phenomena vary continuously with mesh spacing; this paper presents examples of that variation. A mesh-dependent dynamic contact angle model is then presented, that is based on fundamental hydrodynamics and serves as a more appropriate boundary condition at a moving contact line. This new boundary condition eliminates the stress singularity at the contact line; the resulting problem is thus well-posed and yields solutions that converge with mesh refinement. Numerical results are presented of a solid plate withdrawing from a fluid pool, and of spontaneous droplet spread at small capillary and Reynolds numbers. 相似文献
977.
Rosa Di Mundo Vincenzo De Benedictis Riccardo d’Agostino 《Applied Surface Science》2009,255(10):5461-5465
In this work the roughening of polystyrene by means of radiofrequency plasmas fed with CF4 has been studied. The effect of the Ar addition to the feed, the input power and the treatment duration has been investigated in terms of etching and fluorination degree. Wettability and reflectance performances of selected textured surfaces, coated with a fluorocarbon film from a C4F8 fed plasma, have been characterized. All the considered surfaces, even those poorly structured, once coated, show slippery superhydrophobicity, while antireflective transparency appears to be limited to precise texturing characteristics. 相似文献
978.
A superhydrophobic surface was obtained by embedding hydrophobically modified fumed silica (HMFS) particles in polyvinylidene fluoride (PVDF) matrix. The water contact angle (WCA) on the PVDF-HMFS hybrid composite coating is influenced by the content and nature of silica particles in the coating. As the silica concentration in PVDF matrix was increased from 33.3% to 71.4%, WCA increased from 117° to 168° and the sliding angle decreased from 90° to <1°. Surface topography of the coating was examined using scanning electron microscopy. An irregular rough surface structure composed of microcavities and nanofilaments was found to be responsible for the superhydrophobicity. The method is simple and cost-effective and can be used for preparing self-cleaning superhydrophobic coating on large areas of different substrates. 相似文献
979.
980.
空气和氧气气氛下p-GaN/Ni/Au合金性质 总被引:2,自引:1,他引:1
研究了p-CaN上的Au/Ni双金属层在空气气氛和氧气气氛下合金对其欧姆接触性质的影响。使用同步辐射高强度X射线衍射观察到明显的NiO衍射峰。随着合金时间的增加,NiO和Au的结晶性均明显变好,NiO的衍射峰强度随合金时间的增加而增强,同时发现Au(111)沿CaN的(0001)面择优形成单晶。测得Ni/Au-p-CaN-Ni/Au串联电阻在合金后明显降低,表明接触性质改善与结晶性的提高有关。同时发现氧气下合金比空气下合金形成NiO更快,相应的串联电阻也更快地下降。 相似文献