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41.
Jau-Jiun Chen Soohwan Jang F. Ren Yuanjie Li Hyun-Sik Kim D. P. Norton S. J. Pearton A. Osinsky S. N. G. Chu J. F. Weaver 《Journal of Electronic Materials》2006,35(4):516-519
Wet etch rates at 25°C for Zn0.9Mg0.1O grown on sapphire substrates by pulsed laser deposition (PLD) were in the range 300–1100 nm · min−1 with HCl/H2O (5×10−3−2×10−2 M) and 120–300 nm · min−1 with H3PO4/H2O (5×10−3−2×10−2 M). Both of these dilute mixtures exhibited diffusion-limited etching, with thermal activation energies of 2–3 kCal · mol−1. By sharp contrast, the etch rates for ZnO also grown on sapphire by PLD were much slower in similar solutions, with rates
of 1.2–50 nm · min−1 in HCl/H2O (0.01–1.2 M) and 12–54 nm · min−1 in H3PO4/H2O (0.02–0.15 M). The etching was reaction limited over the temperature range 25–75°C, with activation energies close to 6
kCal · mol−1. The resulting selectivity of Zn0.9Mg0.1O over ZnO can be a high as ∼400 with HCl and ∼30 with H3PO4. 相似文献
42.
热氧化磁控溅射金属锌膜合成一维ZnO纳米棒 总被引:6,自引:2,他引:4
利用退火热氧化射频磁控溅射金属锌膜的方法在Si(111)衬底上制备了一维Zn O纳米棒,同时用多种测试手段对样品的晶体结构、表面形貌和光学性能进行了研究.XRD,SEM和TEM的测试结果表明,Zn O纳米棒为单晶相六方纤锌矿结构,呈头簪状向外发散生长,直径在30~60 nm左右,其长度可达几μm.PL 谱测试结果表明:在波长为280 nm光的激发下,在372 nm处有强的近带边紫外光发射和516 nm处的较微弱深能级绿光发射.说明合成的一维Zn O纳米棒的结晶质量和光学性能优良 相似文献
43.
测试了氧化锌颗粒膜电阻响应-恢复特性,讨论了颗粒形态,加热电压、环境气氛、气氛浓度和注入方式等因素对电阻响应-恢复特性的影响。结果表明,随着加热电压的升高,电阻响应-恢复的速度和程度明显加大;断续注入时颗粒膜电阻值的响应随着浓度的增加逐步减弱. 相似文献
44.
从ZnO电阻的非线性特性出发,对采用ZnO作为灭磁电阻时阀片的均流/均能进行理论论述,指出阀片均能性能的好坏主要依赖于阀片自身的特性;分析比较了ZnO阀片的不同选择方法对均流/均能的影响,指出阀片的均流/均能很大程度上取决于可供选择的阀片的库存量.该研究为发电机励磁系统的安全稳定运行提供了有力的保证. 相似文献
45.
GAOHui LIYan YANGLi-ping DENGHong 《半导体光子学与技术》2005,11(2):85-88,106
Hexagonal microtube ZnO was firstly grown on single crystal p-Si (111) substrates by hydrothermal method, and fabricated Ag/n-ZnO and Au/n-ZnO Schottky junction. Schottky effective barrier heights were calculated by I-V measurement. It is confirmed that the presence of a large amount of surface states related possibly to lattice imperfections existed near the surface leads to the pinning of the surface Fermi level at 0.35 eV below the conduction-band edge. Then the fabricated Schottky barrier junctions are evaluated for their use as UV photodetectors. 相似文献
46.
Wanting Li Zixuan Huang Rui Cai Wan Yang Huawei He Yejing Wang 《International journal of molecular sciences》2021,22(1)
Silver-based hybrid nanomaterials are receiving increasing attention as potential alternatives for traditional antimicrobial agents. Here, we proposed a simple and eco-friendly strategy to efficiently assemble zinc oxide nanoparticles (ZnO) and silver nanoparticles (AgNPs) on sericin-agarose composite film to impart superior antimicrobial activity. Based on a layer-by-layer self-assembly strategy, AgNPs and ZnO were immobilized on sericin-agarose films using the adhesion property of polydopamine. Scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray powder diffraction spectroscopy were used to show the morphology of AgNPs and ZnO on the surface of the composite film and analyze the composition and structure of AgNPs and ZnO, respectively. Water contact angle, swelling ratio, and mechanical property were determined to characterize the hydrophilicity, water absorption ability, and mechanical properties of the composite films. In addition, the antibacterial activity of the composite film was evaluated against Gram-positive and Gram-negative bacteria. The results showed that the composite film not only has desirable hydrophilicity, high water absorption ability, and favorable mechanical properties but also exhibits excellent antimicrobial activity against both Gram-positive and Gram-negative bacteria. It has shown great potential as a novel antimicrobial biomaterial for wound dressing, artificial skin, and tissue engineering. 相似文献
47.
Highly conductive transparent aluminium-doped ZnO (ZnO:A1) films were successfully deposited by CW-CO2 laser-induced evaporation. Optimisation of evaporation parameters was based on laser power, substrate temperature, O2 partial pressure in the vacuum chamber and amount of Al in the ZnO source pellet. ZnO:A1 films with an electrical resistivity as low as 6.6 × 10−2Ω·cm and an optical transmission of 80% at 500nm were obtained at laser power of 15 W, substrate temperature of about 200°C, O2 partial pressure of 6—7 × 10−4 Torr and 5wt.% Al. Conductivity of ZnO films can be increased one order via Al-doping in ZnO films. The films obtained by laser-induced evaporation have compared quite favorably with the high quality films obtained by sputtering. 相似文献
48.
采用旋转涂覆法在普通玻璃上制备了Zn0.88Ni0.02Li0.10O薄膜,以X射线和扫描电镜作为表征手段,讨论了不同工艺参数对该薄膜取向和形貌的影响.结果表明:热处理温度和旋涂速度较高时取向增强,形貌较好.VSM磁性测量表明:在玻璃基底和硅基底旋涂的薄膜都没有出现明显的磁滞现象. 相似文献
49.
ZnO压敏陶瓷的非线性功能添加剂 总被引:4,自引:0,他引:4
本文采用单元掺杂与多元掺杂的方法,系统研究了几种过渡金属氧化物添加剂在控制ZnO压敏陶瓷非线性方面的作用,并根据金属阳离子外壳层电子结构稳定性和缺陷化学反应进行了分析,认为阳离子具有不饱和外层电子结构且半径与Zn^2+离子相近的过渡金属氧化物能改善ZnO压敏陶瓷非线性。 相似文献
50.