Straightness measurements with a reflection confocal optical system-an experimental study

Straightness measurement is an important technique in the field of mechanical engineering. We previously proposed a novel optical method for measuring straightness of motion using reflection confocal optics. The advantage of this method in comparison with the transmission optical systems of others [Opt. Laser Technol. 6, 166 (1974)] is that the lateral displacements in the two axes perpendicular to the optical axis and the rotation angles around all three axes can be measured simultaneously. We demonstrate straightness measurements using reflection confocal optics and show these measurements to be in good agreement with the theory.     

Electrical and optical characterisation of silicon and silicon/phosphorus implantsin InP doped with iron

Abstract

Silicon implantations into semi-insulating InP with a wide range of doses and energies have been carried out with the aim of obtaining n type layers suitable for device applications. The electrical activations obtained were typically about 70%, reaching 80% for Si/P co-implants with a dose of 10¹⁴ cm^?2, and the electrical depth profiles showed no redistribution of the implants during annealing. The mobilities obtained after all rapid thermal annealing cycles used were very high, indicating the good crystalline quality of the resulting layers. This was confirmed by Raman scattering measurements, which showed that even if the material is completely amorphised by the implantation, the annealing treatment restores the emissions found for as received unimplanted InP. After Si implantation, the photoluminescence spectrum of the samples showed the appearance of a band at 1·17 eV with high thermal stability, the origin of which was tentatively assigned to V_p–Si_p (P vacancy–Si on P lattice site) complexes.

MST/3423     

基于低温直接键合的血细胞计数芯片结构制备

研究了一种新颖的微流管道血细胞计数器的结构及其工作原理,采用流体动力学对其液体分层流动特性进行了仿真分析,结合图形制备和低温直接键合工艺制作了硅基微流体管道血细胞计数器结构,并采用红外透射方法对微流体管道结构进行了检测.对封闭管道的流通性及结构的键合强度也进行了测量.研究分析表明,采用上述工艺制备的微流体芯片结构与电子器件兼容性好,具有良好的化学惰性和热稳定性,而且管道结构规则,精度高,键合界面层薄,具有较好的应用前景.     

Incorporation of InAs nanostructures in a silicon matrix: growth, structure and optical properties

MBE growth and properties of InAs nanoscale islands formed on silicon are reported. Islands capped with Si emit a photoluminescence band in the 1.3 μm region. Upon annealing at increased substrate temperature, extensive interdiffusion leads to the formation of an InAs solid solution in the Si cap layer. Additionally, InAs-enriched regions with extensions of 6 nm, exhibiting two kinds of ordering, are observed. The ordering of InAs molecules occurs, respectively, in (101) and planes inclined to (110) and planes parallel to the [001] growth direction.     

Confocal reflection readout thresholds in two-photon-induced optical recording

Confocal reflection readout thresholds in two-photon-induced optical recording in photoisomerization polymer are studied both theoretically and experimentally. A threshold of the axial response from a planar reflector with a refractive-index change of the order of 10(-2) is revealed. However, the threshold is reduced to 0.006 when strong forward scattering caused by the recorded bits leads to multiple reflection between the bit and the rare surface, which enhances the image contrast and reduces the readout threshold. The quality of the reconstructed bit image is strongly dependent on the refractive-index mismatch at the sample rare interface as well as the distance between the recorded position and the rare surface.     

Behavior of total internal reflection in optical crystals

It is shown that a crystal can be cut so that one incident beam undergoing reflected from an inclined face inside the crystal excites four beams, two ordinary and two extraordinary, propagating in different directions. Pis’ma Zh. Tekh. Fiz. 25, 46–51 (January 12, 1999)     

Probe-sample interactions in reflection near-field scanning optical microscopy

Reflection near-field scanning optical microscopy with an asymmetric detector orientation is demonstrated. The effects of the probe-sample interactions are studied for different polarizations, detector orientations, and sample reflectivity. It is shown that the orientation of the detector can introduce shadowing in the images, which is opposite from the naive interpretation and which is dependent on the optical properties of the sample. Near-field optical images of metallic test patterns in reflection are shown that exhibit a lateral resolution of 40 nm.     

新型三明治结构铝诱导非晶硅薄膜低温晶化增强

本文对比探索了新型Al/α -Si/Al三明治结构与传统的Al/α -Si双层结构对铝诱导非晶硅薄膜低温晶化结果的影响,结果表明在相同的制备及退火条件下,前者更利于形成高度晶化的多晶硅薄 .膜.本研究工作利用拉曼光谱、掠入射X射线衍射、光学显微镜、方块电阻等表征方法探讨了薄膜厚度比和退火温度对金属诱导非晶硅薄膜晶化的程度、晶体结构以及电学性能的影响,最终制备出了电阻率仅为2.5 Ω·cm的多晶硅薄膜.     

铝诱导非晶硅薄膜低温晶化及结构研究

介绍了一种非晶硅薄膜低温晶化的新工艺－金属诱导非晶硅薄膜低温晶化。在非晶硅膜上蒸镀金属铝薄膜,而后于氮气保护中退火,实现了非晶硅薄膜的低温（＜600℃）晶化。利用X射线衍射、光学显微镜及透射电等测试方法,研究了不同退火工艺对非晶硅薄膜低温晶化的影响,确定了所制备的是多晶硅薄膜。     

贮藏温度对微孔膜包装茶树菇的保鲜效果影响

目的研究贮藏温度对微孔膜包装的茶树菇品质的影响。方法采用微孔保鲜膜包装茶树菇,并在4,6,9,14,20℃等5个温度条件下贮藏,评价其感观质量,并测试茶树菇的质量损失率、硬度、粗蛋白和顶空气体等指标。结果在4,6,9,14,20℃条件下,随着时间推移,茶树的新鲜度下降,质量损失率逐渐增大,硬度逐渐降低,粗蛋白含量也有一定程度减少。在20,14,9,6,4℃贮藏条件下,贮藏期分别为2,6,9,12,15 d。结论在4℃贮藏条件下,微孔膜包装茶树菇能实现更长时间的保鲜。     

Quantification of free-carrier absorption in silicon nanocrystals with an optical microcavity

We present a highly sensitive and accurate microcavity-based technique to quantify the free-carrier absorption (FCA) cross-section of semiconductor quantum-dot ensembles. The procedure is based on measuring the pump-intensity-dependent broadening of the whispering gallery modes (WGMs) of microdisk resonators. We have applied this technique to determine the FCA cross-section of Si nanocrystals (Si-ncs) in the visible-near-infrared wavelength range. Our procedure accounts for the size distribution effects by including the measured wavelength dependence of the excitation cross-section and the decay rate of photoexcited carriers in the analysis. By monitoring the WGM widths at various wavelengths in the 700-900 nm wavelength range, we found that the FCA cross-section follows an approximately quadratic wavelength dependence. The magnitude of the FCA cross-section of Si nanocrystals was determined to be a factor of 7 higher than that in bulk Si. For this reason, these findings have important implications for the design of Si-based lasers and all-optical switching devices in which FCA plays a critical role.     

The structure and optical properties of silicon nanowires prepared by inductively coupled plasma chemical vapor deposition

Silicon nanowires were prepared by vapor-liquid-solid (VLS) mechanism at a growth temperature as low as 380 °C in an inductively coupled plasma chemical vapor deposition system. The nanowires consist of crystalline core surrounded by a thick amorphous silicon shell. An increase in plasma power produces dense and long nanowires with thick amorphous shell, accompanied with a thick uncatalyzed amorphous silicon film on the silicon substrate. Small catalyst nanoparticles are easier activated by plasma to grow the dense and thin nanowires in comparison with the large-size nanoparticles. Moreover, an enhanced optical absorption is achieved due to the strong light trapping and anti-reflection effects in the thin and tapered silicon nanowires with high density.     

含硅光学用增透聚酯薄膜的制备与研究

通过自由基聚合将γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH570)分别与甲基丙烯酸甲酯MMA、甲基丙烯酸丁酯BMA、苯乙烯St进行共聚。采用旋涂法将所得聚合物涂覆于聚对苯二甲酸乙二醇酯(PET)薄膜表面。研究不同含量的硅烷偶联剂、引发剂、不同种类单体对PET薄膜表面性能的影响。数据表明,相比于PET薄膜,涂覆有共聚物的PET薄膜性能有较大变化,透光率有一定程度增大,表面自由能有所减小。     

Deformation of silicon at low temperatures

The dislocation arrangements produced around microhardness indentations made in silicon at room temperature have been studied by transmission electron microscopy. Loops consisting of 30°- and 60°-dislocations are produced and move on the {111} planes. It is suggested that, during indentation, the theoretical shear strength is exceeded locally and that the observed dislocations arise as a result of the accommodation of the displacements due to block slip. On annealing up to 1030° C the loops do not appear to be mobile, rather new loops consisting of edge and screw components are formed which can move large distances.     

Interfacial structure in silicon nitride sintered with lanthanide oxide

Three independent research groups present a comparison of their structural analyses of prismatic interfaces in silicon nitride densified with the aid of lanthanide oxide Ln₂O₃. All three groups obtained scanning transmission electron microscope images which clearly reveal the presence of well-defined Ln segregation sites at the interfaces, and, moreover, reveal that these segregation sites are element-specific. While some results differ across the three research groups, the vast majority exhibits good reproducibility.