共查询到20条相似文献,搜索用时 15 毫秒
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Functionalization control of porous silicon optical structures using reflectance spectra modeling for biosensing applications 总被引:1,自引:0,他引:1
N. Lorrain M. Hiraoui M. GuendouzL. Haji 《Materials Science and Engineering: B》2011,176(14):1047-1053
Modeling and experimental reflectance spectra of porous silicon single layers at different steps of functionalization and protein grafting process are adjusted in order to determine the volume fraction of the biomolecules attached to the internal pore surface. This method is applied in order to control the efficiency of the chemical functionalization process of porous silicon single layers. Using results from single porous silicon layer study, theoretical microcavity is simulated at each step of the functionalization process. The calculated reflectance spectrum is in good agreement to the experimental one. Therefore the single layers study can be applied to multilayer structures and can be adapted for other optical structures such as waveguides, interferometers for biosensing applications. 相似文献
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本文不同的温度下制备多孔硅.通过荧光光谱、光吸收谱、X射线光电子谱研究了多孔硅的光和结构特性.研究结果表明存在着一个制备临界温度343 K,当制备温度从临界温度之下提高到临界温度之上时,多孔硅的荧光和光吸收从红移转向蓝移,同时硅2p电子结合能也从减小转向增大. 相似文献
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在室温下使用过滤阴极真空电弧系统在多孔硅表面沉积大约10纳米左右厚度的铜、铝和钛薄膜,并且在真空下800度退火10分钟.多孔硅层是通过电化学腐蚀硅制得.X射线光电子谱、荧光谱,光吸收谱和X射线衍射谱的研究表明退火后,沉积铜和钛的样品出现明显的光吸收红移和硅2p电子能级移动.这是由于在多孔硅表面形成铜和钛的硅化物而引起的晶体场和电子传输变化所造成的. 相似文献
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高阻硅掩膜选择性生长多孔硅阵列 总被引:1,自引:0,他引:1
介绍一种在低阻P型硅衬底上用氢离子注入技术形成局部高阻硅掩膜,用电化学腐蚀选择性生长多孔硅微阵列的工艺流程。结果证明,用高阻硅掩膜选择性生长多孔硅具有很好的掩蔽效果,生成的多孔硅阵列的有序性和完整性良好。 相似文献
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Porous silicon (PS) was formed on both polished and texturized single crystal silicon (100) by anodic etching. Photoluminescences
(PL) from both of these silicon surfaces were measured and compared. A two-fold enhancement of PL from textured silicon surface
was obtained. This enhancement could be ascribed to the geometry of the textured surface. 相似文献
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用多孔硅外延层转移的方法成功地制备出了SOI材料,卢瑟福背散射/沟道谱(RBS/C)和扩展电阻(SPR)的结果表明获得的SOI材料上层硅具有很好的单晶质量,电阻率分布均匀,上层硅与氧化硅埋层界面陡直。对制备多孔硅的衬底材料也作了研究,结果表明P型重掺杂的硅衬底在暗场下阳极氧化后仍保持很好的单晶性能,用超高真空电子束蒸发方法能外延出质量很好的单晶硅,并且,在一定浓度的HF/H2O2溶液中具有较高的腐蚀选择率,保证了上层硅厚度的均匀性。 相似文献
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Jordan PeckhamG. Todd Andrews 《Thin solid films》2012,520(7):2526-2531
A simple optical method to estimate the porosity of microporous silicon films is described. The technique relies upon determination of film refractive index via measurement of the incident (Brewster) angle corresponding to a minimum in the intensity of light reflected from the air-film interface. The sample porosity is then obtained using an effective medium model. Porosities obtained using this method show general agreement with those obtained using gravimetric means and, where comparison was possible, excellent agreement with those of similarly-prepared films found by low angle X-ray reflectivity. These results confirm the general applicability of this technique to the determination of microporous silicon film porosity. 相似文献
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以p型单晶硅片为研究对象,在单晶硅片表面采用化学腐蚀方法制备多孔硅层,通过实验选取制备多孔硅的最佳工艺条件,采用SEM观察多孔硅表面形貌,以及用微波光电导法测试少子寿命的变化情况。结果表明,在相同的腐蚀溶液配比条件下腐蚀11min得到的多孔硅层的表面形貌最好,孔隙率最大。在850℃下热处理150min时样品少子寿命的提高达到最大,不同腐蚀时间的样品少子寿命提高程度不同,腐蚀11min的样品少子寿命提高最大,约有10%左右。多孔层的形成伴随着弹性机械应力的出现,引起多孔层-硅基底界面处产生弹性变形,这有利于缺陷和金属杂质在界面处富集。另外,多孔硅仍具有晶体结构,但其表面方向上的晶格参数要比初始硅的晶格参数大,也有利于金属杂质向多孔层迁移。 相似文献
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Luca De Stefano Ivo Rendina Luigi Moretti Andrea Mario Rossi 《Materials Science and Engineering: B》2003,100(3):271-274
A porous silicon multilayer, constituted by a Fabry–Pèrot cavity between two distributed Bragg reflectors, is exposed to vapor of several organic species. Different resonant peak shifts in the reflectivity spectra, ascribed to capillary condensation of the vapor in the silicon pores, have been observed. Starting from experimental data, the layer liquid volume fractions condensed in the sensing stack have been numerically estimated. Values ranging between 0.27 (for ethanol) and 0.33 (for iso-propanol) have been found. Time-resolved measurements show that the solvent identification occurs in less then 10 s. 相似文献
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用氧化多孔硅作牺牲层制备悬空微结构 总被引:1,自引:0,他引:1
提出一种新的牺牲层工艺。先将阳极氧化生成的多孔硅在300℃的氮气氛下进行退火以稳定其多孔结构,然后将其在700℃下氧化成为具有多孔结构的二氧化硅。用氧化的多孔硅材料作为牺牲层材料,既可以保留多孔硅牺牲层材料释放迅速的优点,又克服了多孔硅在释放时的局限性。实验运用氧化的多孔硅材料作牺牲层成功制备了悬空振膜和悬臂梁结构。 相似文献
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D. Navarro-Urrios M. Ghulinyan P. Bettotti E. Rigo C.J. Oton N.E. Capuj F. Lahoz I.R. Martín L. Pavesi 《Optical Materials》2009,31(10):1488
We report on a new hybrid approach to realize optical slab waveguides for optical amplification purposes. The structure consists of a dye-doped polymer core (PMMA) deposited over an oxidized porous silicon (PS) cladding layer formed on a silicon wafer. The very low refractive index (n = 1.16) achievable in the cladding allows obtaining monomodal behavior with high confinement factors (ΓTE = 96%) even for very thin cores (400 nm). Optically excited guided luminescence shows stimulated emission, strong line narrowing and a clear threshold and superlinear behavior with pump energy. By means of the variable stripe length (VSL) technique, values of net optical gain up to 113 dB/cm (constant over 3 mm) and absolute amplification values up to 34 dB have been measured at 694 nm when pumping with 80 mJ/cm2 energy pulses. These results validate the use of oxidized PS as a cladding layer in silicon photonics. 相似文献
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Electrochemical etching with step-gradient current was applied to form gradient-porosity porous silicon (PS) layer on n-Si substrate and Al/gradient-porosity. PS/n-Si structure was fabricated to extract its opto-electronic properties using reflectivity, spectral response, and scanning electron microscopy. A conventional single-layer PS etched with constant-current was also compared. Compared to the single-layer PS, the absorption wavelength of gradient-porosity PS is blue-shifted due to a smaller quantum size, hence a wider band-gap. Such a wider band-gap leads to a larger barrier-height in Al/gradient-porosity PS than that in Al/single-layer PS one. More dangling bonds are found on the surface of gradient-porosity PS owing to inhomogeneous etching, thus a poor electronic property, though it has a lower broadband antireflection than single-layer PS. 相似文献
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钴钝化多孔硅的制备及其场发射特性研究 总被引:2,自引:0,他引:2
采用化学染色腐蚀法在Co(NO3)2 和HF酸组成的腐蚀液中制备了钴钝化多孔硅,其表面形貌由垂直于表面分布的尺度为0.5~1.5μm 的硅尖组成,部分硅尖顶端还有0.1~0.5μm的圆形孔洞,硅尖的面密度约为1.0×108 个/cm2,多孔硅层厚度约为2μm。XPS分析结果表明,钴原子仅存在于多孔硅表面非常薄的一层内。其场发射具有较好的可靠性和可重复性,开启场强一般为2.3V/μm 左右,场强为5.4V/μm时,亮点均匀而且密集,发射电流密度达到30μA/cm2 左右。 相似文献