微球辅助相移干涉三维形貌测量

相移干涉显微镜在微观物体三维形貌的重构横向分辨率上受衍射极限影响,一般在微米级,限制其应用。将高折射率微球嵌入Mirau型相移干涉显微系统中,利用微球超分辨机理提高了其三维重构横向分辨能力,通过和原子力显微镜的测量对比验证了方法的可行性。仿真分析了微球尺寸对光子纳米喷流效应和超分辨能力的影响;同时使用两种不同尺寸的微球对275nm线宽的标准光栅样品进行了三维形貌重构;结果表明,在两种微球的辅助下,相移干涉显微系统均能够精确还原样品的三维结构,光栅深度测量结果与原子力显微镜结果相当。在微球辅助下,系统的横向分辨能力达到了275nm,相较于不使用微球的情况下提高了2.1倍,微球的最高放大率达到了3.4倍。系统在微纳米测量等领域具有较高的应用价值。     

基于双晶退火衬底的高温超导纳米量子干涉仪在液氦液氮温区下的输运特性

超导纳米量子干涉器件是近年来发展起来的一种新型超导器件, 通过现代微纳加工技术将其超导环缩小到纳米尺寸, 构成高度灵敏的微观自旋探测器, 理论上可以达到测量单电子自旋的灵敏度. 同时, 高温超导由于具有较高的临界温度和上临界场也备受关注. 然而, 相比于低温超导量子干涉器件, 高温超导量子干涉器件的1/f 噪声更加显著, 这限制了其在低频下的应用. 本文基于双晶衬底技术, 通过聚焦离子束加工制备高温超导纳米量子干涉仪, 并对其在液氦和液氮温区下的电学性能、4.2 K 下的磁通噪声进行表征. 实验发现, 通过预先退火处理钛酸锶双晶衬底, 可以有效改善衬底表面的粗糙度, 进而优化高温超导纳米量子干涉仪的1/f 磁通噪声. 最终得到低频下(1 Hz)的磁通噪声灵敏度为4.9 μΦ0/Hz1/2 , 比未事先预处理的小一到两个数量级, 这对于推进高温超导纳米量子干涉器件在低频下的应用意义重大.     

用于微位移测量的笔束激光干涉仪

介绍了一种基于空间干涉原理的亚微米零差干涉位移测量方法。该方法是对笔束激光干涉仪在微位移测量领域的应用 ,干涉仪的测量精度不受光束波前畸变等光源噪声的影响。给出了干涉仪主要结构参数的选取原则 ;构建了用于微位移测量的笔束激光干涉仪实验系统。实验结果表明 ,该系统具有纳米测量分辨率。     

基于多光束混合外差干涉的相位增强技术研究

激光外差干涉测量技术是微振动探测的重要手段,随着微纳应用的拓展,人们对精密测量系统的相位检测灵敏度提出了更高的要求.传统提高测量灵敏度的方法有优化外差干涉系统方案、改进相位重建算法和降低关键器件噪声等.本文提出了一种多光束混合干涉的相位增强方法,经过理论推导和实验验证得到如下近似条件:校正光与信号光的初相位相差πrad情况下,两光束的功率越接近,系统对目标的弱振动振幅响应越大.实验设计的两光束功率相差1%时,观察到了最大146倍的增强效果,该方法在微振动物体高灵敏度测量上具有较大的应用价值,在现有器件指标和相位解调算法不变的基础上可大幅提高外差干涉测量系统的探测能力.     

微尺度薄膜热导率测试技术

随着器件尺寸进入到微 /纳米尺度 ,其热物性与体材料相比有了很大差别。在器件热性能和可靠性研究过程中 ,对热导率的测量成为了关键技术之一。本文概述了SiO2 、SiNx、金刚石等薄膜在微小型器件中的用途及其热导率测试技术的发展 ,并进一步总结了用于薄膜热导率测量的常用方法     

微探针纳米尺度振动测试的实验研究

微探针是扫描探针显微镜(SPM)的重要组成部件,其共振频率等振动特性直接影响系统的性能。给出了系统微探针共振频率的测试方法,对微探针在压电陶瓷驱动力作用下的受迫振动进行了有限元分析。提出了相位变化0.1°所对应的0.1nm位移分辨率的双频激光外差干涉光学测量系统,对微探针纳米尺度振动特性进行了测试对比实验,并对SPM标定样块进行了比对分析。实验结果验证了双频激光外差干涉测量方法的可行性和其应用价值。     

微尺度薄膜热导率测试技术

随着器件尺寸进入到微／纳米尺度，其热物性与体材料相比有了很大差别。在器件热性能和可靠性研究过程中，对热导率的测量成为了关键技术之一。本文概述了SiO2、SiNx、金刚石等薄膜在微小型器件中的用途及其热导率测试技术的发展，并进一步总结了用于薄膜热导率测量的常用方法。     

基于傅里叶变换光学系统的动态多光束干涉光刻

变参量微纳结构在二维平面内交叉、分段排布可以实现超表面器件的多路复用和多功能集成。为实现交叉、分段变参量微纳结构的干涉制备,提出了孔径光阑与相位元件联合调制的傅里叶变换光学系统。利用透镜的傅里叶变换特性和相位元件衍射光线的几何传播特性,阐明了傅里叶成像面上交叉、分段分布的多干涉光场的生成方法与调控规律。同时,针对目标分布的变参量微纳结构,反演设计了多像素孔径光阑与基于光栅和变参量光栅的相位元件,实验获得了交叉、分段分布的多干涉光场。将多干涉光场与微缩投影结合可制备分段排布的纳米光栅。将动态调控的多干涉光场分时复用可制备分段排布的变参量纳米光栅。     

基于衍射光栅的干涉式精密位移测量系统

介绍了基于几何莫尔条纹原理和衍射干涉原理的两种光栅精密位移测量系统及各自的特点。综述了国内外对光栅干涉式精密位移测量系统的研究进展,总结了系统存在的关键问题及发展趋势。光栅干涉式精密位移测量系统的优点是对环境要求小,测量分辨率和精度较高,结构紧凑,成本低。该系统需要解决的问题包括提高光栅以及光学元器件制造和安装精度;寻求一种更高精度的检测手段对光栅位移测量系统进行标定等。光栅干涉式精密位移测量系统的发展方向为更高测量分辨率和精度,大量程、多维度测量以及尺寸小巧。该系统在现代工业加工精密制造领域将具有更广阔的应用前景。     

利用Mirau显微干涉仪测量微器件的纳米级运动

描述了一种用于微机电系统（MEMS）纳米级微运动测量的Mirau显微干涉系统.该系统利用商业化的Mirau显微干涉仪，它直接安装在光学显微镜上，用于测量一个表面微加工水平谐振器的三维运动.面内运动取决于亮场在最佳焦平面处的图像，而离面运动则取决于频闪得到的干涉图像，该图像在物镜纳米定位器的8个不同位置处得到.实验结果表明了系统进行面内和离面运动测量的纳米级分辨力.     

Profile measurement system based on linnik-type interferometric microscope for visible-light region and infrared-light region

A profile measurement system consisting of linnik-type interferometric microscope, light source and cameras is developed based on white-light scanning interferometry extending from the visible-light region to the infrared-light region. Three-dimensional profiles of microstructures are obtained via a phase-stepping algorithm using a CMOS array camera for the visible-light region and an InGaAs CCD array camera for the infrared-light region. Errors of the measurement system along with extensive applications in MEMS device profile reconstruction of top surface, sidewall and internal structures are discussed in detail.     

Testing micro devices with fringe projection and white-light interferometry

Optical sensors are very suitable for the analysis of microscopic structures and micro devices. We compare two very promising methods: the white-light interferometry and the fringe projection technique for the application to this task. The fringe projection is very useful for fast measurement of objects with vertical dimensions of some μm. White-light interferometry is especially useful for highly resolved 3-D measurements. Furthermore, we present a new technique, the scanning fringe projection (SFP), which enables absolute 3-D measurements with one single grating period.     

Micro-profile measurement based on windowed Fourier transform in white-light scanning interferometry

White-light scanning interferometry (WLSI) has been widely used in micro-profile measurement such as Micro-Electro-Mechanical Systems (MEMS) and Computer Generated Hologram (CGH) diffractive elements. It does not contain phase ambiguity problem which is often encountered in monochromatic wavelength interferometry. This paper presents an algorithm based on windowed Fourier transform (WFT) to extract the phase of a white-light interferogram and compensates for the difference in zero optical path difference (ZOPD) position in WLSI. With the WFT technique, the center wavelength of a white-light source and the phase of a white-light interferogram could be retrieved simultaneously. The effect of noise, scanning interval of a piezoelectric transducer (PZT) and the window size of WFT are also analyzed. Both simulated and experimental results show that the proposed algorithm has good noise immunity and is able to accurately measure the micro-profile of a specimen.     

Continuous wavelet transform for micro-component profile measurement using vertical scanning interferometry

White-light interferometric techniques have been widely used in three-dimensional (3D) profiling. This paper presents a new method based on vertical scanning interferometry (VSI) for the 3D profile measurement of a micro-component that contains sharp steps. The use of a white-light source in the system overcomes the phase ambiguity problem often encountered in monochromatic interferometry and also reduces speckle noises. A new algorithm based on the continuous wavelet transform (CWT) is used to retrieve the phase of an interferogram. The algorithm accurately determines local fringe peak and improves the vertical resolution of the measurement. The proposed method is highly resistant to noise and is able to achieve high accuracy. A micro-component (lamellar grating) fabricated by sacrificial etching technique is used as a test specimen to verify the proposed method. The measurement uncertainty of the experimental results is discussed.     

扫描白光干涉测量技术的算法比较

干涉条纹零光程差位置的确定是扫描白光干涉测量的关键技术之一。介绍了扫描白光干涉法测量物体轮廓的原理,讨论了确定白光干涉条纹零级条纹位置的几种方法,并对随机生成的表面进行了大量的数字模拟测量和分析比较,得出了各种算法对测量准确度的影响。研究结果对白光干涉的应用研究提供了可靠的理论根据。     

Dynamic out-of-plane profilometry for nano-scale full-field characterization of MEMS using stroboscopic interferometry with novel signal deconvolution algorithm

A dynamic 3D nano-scale surface profilometer using stroboscopic white-light interferometry with novel signal deconvolution was developed to deliver dynamic surface profilometry with a measurement bandwidth of up to a MHz scale and a vertical resolution reaching 1 nm. Previous work using stroboscopic microscopic interferometry for dynamic characterization of micro-(opto)electromechanical systems (M(O)EMS) has been limited in measurement bandwidth of less than a few hundred kHz due to physical length limitation of stroboscopic light. For high-resonance mode analysis, the stroboscopic light pulse is too lengthy to capture the moving fringes from dynamic motion of the detected structure. In view of this need, a novel deconvolution algorithm using correction of the light response was developed for removing potential image blurs caused by the unavoidable vibration of the tested parts. With this advance in technology, the bandwidth of dynamic measurement can be significantly increased without sacrificing measurement accuracy. A microcantilever beam used in AFM was measured to verify the capability of the system in accurate characterization of dynamic behaviors of M(O)EMS.     

Coherence Spectrotomography of Layered Medium with White-Light Continuum

In low-coherence reflectometry, the light scattered back from a scattering medium is expected to carry information about the spectral properties of the medium as well as range information about the reflective boundaries and backscattering sites. We built and evaluated a white-light interferometry system that gives the range and spectral information about the medium using the white-light continuum. The white-light continuum gives an extremely bright and broad spectrum. Experimental results on multi-layered media are presented.     

用光纤白光干涉技术测量晶体的弹光系数

运用折射率椭球分析晶体的弹光效应,给出了三方晶系沿光轴方向的应力与折射率的变化关系.针对晶体的各向异性和折射率随应力变化很小的因素,利用白光干涉技术空间分辨率高的特点,将白光干涉技术拓展到研究各向异性材料的光学性质. 并对测量群折射率的光纤迈克尔逊白光干涉技术进行了改进.采用光栅位移传感器和全保偏光纤提高反射扫描镜的位移准确度.通过测量石英晶体在不同外力下折射率的变化情况,确定了晶体的弹光系数. 石英晶体的弹光系数P33和P13分别为0.110和0.279,其准确度达到0.001.     

基于小波降噪的偏振耦合检测分析

理论分析了基于白光干涉的保偏光纤偏振模式耦合检测原理,并以迈克尔逊干涉仪对保偏光纤的偏振耦合的耦合强度和耦合点的位置进行了测试.由于机械式扫描干涉仪和信号处理电路会受到环境干扰和各种噪声的影响,限制了系统偏振耦合检测的灵敏度,应用小波变换对检测信号进行了分析,采用软阈值方法降噪处理,有效地去除了各种干扰和噪声,提高了干...     

Comparison between a white-light interferometer and a tactile formtester for the measurement of long inner cylindrical surfaces

Shape measurements of engineering surfaces are an interesting and important application for white-light interferometry (WLI). Due to some factors such as: (a) the high-processing speed, (b) the ability to measure a huge quantity of points of the evaluated surface, and (c) the non-contacting nature; WLI has become a valuable tool for practical applications. This paper shows the achieved comparison between a modified white-light interferometer and an established measurement system, namely a formtester with a tactile spherical stylus sensor, which is the most commonly used instrument in the industry. Furthermore, this paper shows that the combination between the modified white-light interferometer and an adequate measurement and processing strategy has enabled to obtain a good agreement between optical and tactile measurements of long inner cylindrical surfaces. A cloud of points (COP) measured with the modified white-light interferometer has presented a standard deviation of about 0.3 μm when it was compared with formtester measurement of the same parts.