共查询到20条相似文献,搜索用时 421 毫秒
1.
纳米α-Al2O3磨料抛光单晶硅片光滑表面的形成机理 总被引:2,自引:0,他引:2
"将纳米α-Al2O3粉体配制成抛光液并冷冻成冰结抛光垫对单晶硅片进行了抛光,用原子力显微镜观察了抛光表面的微观形貌并测量了其表面粗糙度,采用透射电镜观察了单晶硅片抛光后的断面形貌.为进一步分析抛光过程中的化学作用机理,采用X射线光电子能谱分析了单晶硅片抛光后表面的化学成分.利用纳米压痕仪的划痕附件对单晶硅片进行了划痕测试,研究了抛光过程中的机械作用机理.结果表明纳米α-Al2O3磨料冰冻抛光单晶硅片时,在1 mm£1 mm的范围内得到了微观表面粗糙度为0.367 nm的超光滑表面,亚表面没有任何损伤,材 相似文献
2.
本文介绍了利用浸液抛光法和弹性可变形磨盘加工金属圆筒形非球面镜超光滑表面的方法和结果。其表面粗糙度由原来的Ra0.01~Ra0.02(传统抛光法)提高到目前的Ra0.002。 相似文献
3.
4.
无损伤超光滑LBO晶体表面抛光方法研究 总被引:1,自引:0,他引:1
传统的抛光LBO晶体的方法是选用金刚石抛光粉在沥青抛光盘上抛光。沥青盘易于变形不容易修整,金刚石粉特别硬容易损伤抛光晶体表面。抛光过程中,抛光盘和抛光粉的选择是非常重要的,直接影响到抛光效率和最终的表面质量。新的抛光LBO晶体的方法,其抛光过程是一个化学机械过程,抛光盘、抛光粉和抛光材料相互作用。选用两种抛光盘(培纶和聚氨酯盘),三种较软的抛光磨料(CeO2,Al2O3和SiO2胶体),并在LBO晶体的(001)面进行抛光实验。用原子力显微镜测量和分析了表面粗糙度。结果表明,使用聚氨酯盘和SiO2胶体能够获得无损伤超光滑的LBO晶体表面,其表面粗糙度的RMS为0.3nm。 相似文献
5.
介绍了纳米压痕测试技术的基础理论及纳米压痕法常用的Oliver -Pharr方法的计算原理。采用纳米压痕试验测得不同表面粗糙度的Li2O-Al2O3-SiO2微晶玻璃样品的纳米硬度、弹性模量和载荷-位移曲线。结果表明样品表面粗糙度会降低纳米压痕测试结果的稳定性、准确性和可靠性:样品表面粗糙度越小,测得的纳米硬度和弹性模量值波动越小,载荷-位移曲线重合性越高。随着最大载荷的增大,测得的弹性模量逐渐减小,其原因是压痕边缘材料发生了塑形变形。在超光滑表面样品(Ra=0.9 nm)上测得较为准确的Li2O-Al2O3-SiO2微晶玻璃纳米硬度和弹性模量值分别为8.8 GPa和7.79 GPa。纳米压痕测试结果的重合度对于评价超光滑表面完整性研究具有指导意义。 相似文献
6.
反应烧结碳化硅平面反射镜的光学加工 总被引:7,自引:0,他引:7
介绍了100mm口径反应烧结碳化硅平面反射镜的光学加工工艺流程。按照流程依次介绍了在粗磨成形、细磨抛光和精磨抛光过程中使用的机床、磨具和磨料以及采用的工艺参数和检测方法。介绍了在光学加工各个步骤中应注意的问题。展示了加工后反应烧结碳化硅平面反射镜的实物照片。给出了面形精度和表面粗糙度的检测结果:面形精度(95%孔径)均方根值(RMS)为0.030λ(λ=632.8nm),表面粗糙度RMS值达到了1.14nm(测量区域大小为603 6μmⅹ448 4μm)。 相似文献
7.
8.
单点金刚石车削技术被广泛应用于光学表面的超精密加工。然而,车削表面固有的周期性残留刀痕结构将增强表面散射效应,恶化元件光学性能。为了抑制散射以获得高质量光学表面,采用气囊抛光技术主动改变车削表面周期性刀痕结构。基于Taguchi正交试验,以表面粗糙度及功率谱密度的改善率为设计指标,分析获得了最优抛光参数。采用该最优参数对一精车表面进行了抛光试验,抛光后表面粗糙度Ra由3.81 nm降到1.42 nm,各空间频率功率谱密度大幅降低,同时表面的衍射条纹消失。试验结果验证了所采用的抛光及相应优化方法的有效性,具有重要的工程应用价值。 相似文献
9.
单点金刚石车削技术被广泛应用于光学表面的超精密加工。然而,车削表面固有的周期性残留刀痕结构将增强表面散射效应,恶化元件光学性能。为了抑制散射以获得高质量光学表面,采用气囊抛光技术主动改变车削表面周期性刀痕结构。基于Taguchi正交试验,以表面粗糙度及功率谱密度的改善率为设计指标,分析获得了最优抛光参数。采用该最优参数对一精车表面进行了抛光试验,抛光后表面粗糙度Ra由3.81 nm降到1.42 nm,各空间频率功率谱密度大幅降低,同时表面的衍射条纹消失。试验结果验证了所采用的抛光及相应优化方法的有效性,具有重要的工程应用价值。 相似文献
10.
11.
12.
S. Sali M. Boumaour M. Kechouane S. Kermadi F. Aitamar 《Physica B: Condensed Matter》2012,407(13):2626-2631
A ZnO thin film was successfully synthesized on glass, flat surface and textured silicon substrates by chemical spray deposition. The textured silicon substrate was carried out using two solutions (NaOH/IPA and Na2CO3). Textured with Na2CO3 solution, the sample surface exhibits uniform pyramids with an average height of 5 μm. The properties and morphology of ZnO films were investigated. X-ray diffraction (XRD) spectra revealed a preferred orientation of the ZnO nanocrystalline film along the c-axis where the low value of the tensile strain 0.26% was obtained. SEM images show that all films display a granular, polycrystalline morphology. The morphology of the ZnO layers depends dramatically on the substrate used and follows the contours of the pyramids on the substrate surface. The average reflectance of the textured surface was found to be around 13% and it decreases dramatically to 2.57% after deposition of a ZnO antireflection coating. FT-IR peaks arising from the bonding between Zn–O are clearly represented using a silicon textured surface. A very intense photoluminescence (PL) emission peak is observed for ZnO/textured Si, revealing the good quality of the layer. The PL peak at 380.5 nm (UV emission) and the high-intensity PL peak at 427.5 nm are observed and a high luminescence occurs when using a textured Si substrate. 相似文献
13.
《Current Applied Physics》2007,7(2):193-197
Highly transparent and adherent nanocrystalline large-area ZnS thin films were grown on the slide glass and the SnO2-coated glass substrate by chemical deposition using an aqueous solution containing zinc sulfate and thioacetamide. The films were characterized by scanning electron microscopy, X-ray diffraction, transmission electron microscopy, UV–Vis transmission and photoluminescence. The SEM morphologies of the films revealed a string-like structure formed by the smaller particle on the ZnS film surface. The average particle size was confirmed, using XRD analysis and TEM observation, to be about 3–4 nm. 相似文献
14.
研究了不同尺寸SiO2胶体微球形成纳米结构薄膜的光学传输特性和光子带隙。通过在玻璃基底上自组装透光的SiO2胶体微球形成胶体晶体薄膜, 依据布拉格定律,分析微球尺寸对胶体晶体光子带隙的影响。为实现可见光波段的全方位减反射,提出通过改变胶体粒径将胶体晶体带隙位置移动至紫外波段,理论计算得出当粒径为112 nm,占空比为0.45时能实现可见光波段0.5%的平均反射率。实验结果表明,玻璃基底在400~800 nm间的平均反射率从4.3%降低至0.7%,最小反射率达0.3%。通过控制微球粒径移动光子带隙位置,优化晶体结构参数实现了可见光波段的减反射,有效提高了光学组件对可见光的利用率。 相似文献
15.
A fast method for preparing of silver particle layers on glass substrates with high application potential for using in surface enhanced Raman spectroscopy (SERS) is introduced. Silver particle layers deposited on glass cover slips were generated in one-step process by reduction of silver nitrate using several reducing agents (ethylene glycol, glycerol, maltose, lactose and glucose) under ultrasonic irradiation. This technique allows the formation of homogeneous layers of silver particles with sizes from 80 nm up to several hundred nanometers depending on the nature of the used reducing agent. Additionally, the presented method is not susceptible to impurities on the substrate surface and it does not need any additives to capture or stabilize the silver particles on the glass surface. The characteristics of prepared silver layers on glass substrate by the above mentioned sonochemical approach was compared with chemically prepared ones. The prepared layers were tested as substrates for SERS using adenine as a model analyte. The factor of Raman signal enhancement reached up to 5·105. On the contrary, the chemically prepared silver layers does not exhibit almost any pronounced Raman signal enhancement. Presented sonochemical approach for preparation of silver particle layers is fast, simple, robust, and is better suited for reproducible fabrication functional SERS substrates than chemical one. 相似文献
16.
The particle size distribution, morphology and optical properties of the Au nanoparticle (NP) structures for surface enhanced
Raman signal (SERS) application are investigated in dependence on their preparation conditions. The structures are produced
from relatively thin Au films (10–20 nm) sputtered on fused silica glass substrate and irradiated with several pulses (6 ns)
of laser radiation at 266 nm and at fluencies in the range of 160–412 mJ/cm2. The SEM inspection reveals nearly homogeneously distributed, spherical gold particles. Their initial size distribution of
the range of 20–60 nm broadens towards larger particle diameters with prolonged irradiation. This is accompanied by an increase
in the uncovered surface of the glass substrate and no particle removal is observed. In the absorption profiles of the nanostructures,
the broad peak centred at 546 nm is ascribed to resonant absorption of surface plasmons (SPR). The peak position, halfwidth
and intensity depend on the shape, size and size distribution of the nanostructured particles in agreement with literature.
From peak intensities of the Raman spectra recorded for Rhodamine 6G in the range of 300–1800 cm−1, the relative signal enhancement by factor between 20 and 603 for individual peaks is estimated. The results confirm that
the obtained structures can be applied for SERS measurements and sensing. 相似文献
17.
The present study investigated fluid flow and natural convection heat transfer in an enclosure embedded with isothermal cylinder. The purpose was to simulate the three-dimensional natural convection by thermal lattice Boltzmann method based on the D3Q19 model. The effects of suspended nanoparticles on the fluid flow and heat transfer analysis have been investigated for different parameters such as particle volume fraction, particle diameters, and geometry aspect ratio. It is seen that flow behaviors and the average rate of heat transfer in terms of the Nusselt number (Nu) are effectively changed with different controlling parameters such as particle volume fraction (5 % ≤ φ ≤ 10 %), particle diameter (d p = 10 nm to 30 nm) and aspect ratio (0.5 ≤ AR ≤ 2) with fixed Rayleigh number, Ra = 105. The present results give a good approximation for choosing an effective parameter to design a thermal system. 相似文献
18.
19.
Xiaodong Zhou Kai Yu Liu Nan Zhang Dong-Hwan Kim Christina Tan 《Journal of nanoparticle research》2011,13(7):2919-2927
Dispersing nanospheres on a large glass substrate is the key to fabricate noble metal nanostructures for localized surface
plasmon resonance through dispersed nanosphere lithography. This article reports that by modifying the glass surface with
low dose ion implantation and successively dip coating the surface with poly(diallyldimethyl ammonium chloride) (PDDA), polystyrene
or silica nanospheres can be dispersed on a large glass substrate. Investigation shows that several kinds of ions, such as
silicon, boron, argon, and arsenic, can improve the nanosphere dispersion on glass, attributed to the ion bombardment-caused
silicon increment. Ion implantation imposes no surface roughness or optical loss to the glass substrate, thus this method
is suitable for localized surface plasmon resonance application. Experiments show silicon ion implantation can best disperse
the nanospheres. For the gold nanostructures obtained by obliquely evaporating 30 nm of gold film onto the polystyrene nanospheres,
which are dispersed on a silicon ion implanted glass substrate, a localized surface plasmon resonance sensitivity of 242 nm/RIU
is achieved. 相似文献
20.
We report a new structure for broadband antireflection coating by dip-coating technique, which has minimal cost and is compatible with large-scale manufacturing. The coatings are prepared by depositing SiO 2 sol-gel film on a glass substrate, subsequently depositing SiO 2 single-layer particle coating through electrostatic attraction, and depositing a final very thin SiO 2 sol-gel film to improve the mechanical strength of the whole coating structure. The refractive index of the structure changes gradually from the top to the substrate. The transmittance of a glass substrate has been experimentally found to be improved in the spectral range of 400 1 400 nm and in the incidence angle range from 0 to at least 45 . The mechanical strength is immensely improved because of the additional thin SiO 2 sol-gel layer. The surface texture can be applied to the substrates of different materials and shapes as an add-on coating. 相似文献