CN107144235A - A kind of article surface Shape measure method and device - Google Patents
A kind of article surface Shape measure method and device Download PDFInfo
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Abstract
本发明公开一种物品表面形貌检测方法：①低相干光线从三端环形器的端口1射进，从端口2射出，经第一透镜准直后从x‑y扫描振镜中的x振镜射入，y振镜射出；③射出的光线经第二透镜聚焦后经过一分光片被分为两部分光线，一部分从玻璃底面反射，作为参考光，另一部分穿透玻璃后射到被样品表面并反射，作为样品光；④两部分光线共光路返回，经第二透镜汇聚到扫描振镜的y振镜，经y振镜射入x振镜，然后射出；⑤光线经第一透镜汇聚进入三端环形器的端口2，然后从端口3射出；⑥从端口3射出的光线进入光谱仪，光谱仪传递数据给电脑；⑦扫描振镜对样品进行逐点扫描；⑧电脑计算相邻位置的相位差和深度差Δz，得到最终样品表面形貌的定量分布情况。
The invention discloses a method for detecting the surface topography of an article: ①Low coherent light enters from port 1 of a three-terminal circulator, exits from port 2, and is collimated by the first lens to scan the x-vibrator in the x-y vibrating mirror ③ The emitted light is focused by the second lens and then divided into two parts by a beam splitter, one part is reflected from the bottom of the glass as a reference light, and the other part penetrates the glass and then reaches the sample The surface is reflected and used as sample light; ④The two parts of the light return through the common optical path, converge to the y galvanometer of the scanning galvanometer through the second lens, enter the x galvanometer through the y galvanometer, and then exit; ⑤The light converges through the first lens Enter port 2 of the three-terminal circulator, and then emit from port 3; ⑥The light emitted from port 3 enters the spectrometer, and the spectrometer transmits data to the computer; ⑦The scanning galvanometer scans the sample point by point; ⑧The computer calculates the phase of the adjacent position Difference and the depth difference Δz to obtain the quantitative distribution of the surface topography of the final sample.
Description
技术领域：Technical field:
本发明涉及一种物品表面形貌检测方法及装置。The invention relates to a method and a device for detecting surface topography of an article.
背景技术：Background technique:
微观表面形貌检测在工业产品检测、机械制造、电子工业等领域均有非常重要的应用价值，随着现代电子工业、光学精微加工及微机电技术的发展，对微观表面精度的要求越来越高，表面形貌质量成为保证和提高机械、电子及光学系统性能、质量和寿命的关键因素之一。在最近几十年里，国内外微观表面形貌测量领域出现了许多新技术和新方法，使测量精度不断提高，己从微米尺度进入到纳米甚至亚纳米尺度。目前微观表面形貌测量方法可分为两大类:接触式和非接触式。触针式轮廓仪是目前使用比较广泛的接触式表面轮廓测量仪，具有测量范围大、分辨率高、测量结果稳定可靠、重复性好等优点，其轴向测量分辨率可达1nm或更小，但在微观表面轮廓检测中，通常要求不能和样品表面接触，接触检测会导致样品表面损伤。纳米级精度非接触测量方法可分为非光学方法和光学方法两大类，非光学测量方法包括扫描隧道显微镜和原子力显微镜，扫描隧道显微镜横向分辩率为0.1nm，轴向分辨率0.01nm量级，其轴向和横向测量范围较小(约1μm)，扫描隧道显微镜是通过隧道电流反映被测表面形貌，因此,只能测量导体或半导体,而且测量必须在真空中进行。原子力显微镜的轴向分辨率达到0.1nm，横向分辨率约为10nm，既可以检测导体，也可以检测非导体，但具有成像范围小、受探头影响大的缺点。纳米级光学测量方法分为两类：(1)结合色差和共焦显微技术的色差共焦光谱技术(Chromatic confocal spectrum,CCS)，(2)干涉测量方法，包括：单色光相移干涉法(Phase-shifting interferometry,PSI)、垂直扫描白光干涉法(Vertical scanning white-light interferometry,SWLI)、白光光谱干涉法(White-light spectral interferometry,WLSI)及外差干涉法(Heterodyneinterferometry,HI)。Microscopic surface topography detection has very important application value in industrial product testing, machinery manufacturing, electronics industry and other fields. With the development of modern electronics industry, optical micromachining and micro-electromechanical technology, the requirements for microscopic surface precision are becoming more and more High, the quality of surface topography has become one of the key factors to ensure and improve the performance, quality and life of mechanical, electronic and optical systems. In recent decades, many new technologies and methods have emerged in the field of microscopic surface topography measurement at home and abroad, which have continuously improved the measurement accuracy, and have entered the nanometer or even sub-nanometer scale from the micrometer scale. At present, the microscopic surface topography measurement methods can be divided into two categories: contact and non-contact. The stylus profiler is a contact surface profile measuring instrument widely used at present. It has the advantages of large measurement range, high resolution, stable and reliable measurement results, and good repeatability. Its axial measurement resolution can reach 1nm or less , but in microscopic surface profile detection, it is usually required not to be in contact with the sample surface, and contact detection will cause damage to the sample surface. Nanoscale precision non-contact measurement methods can be divided into two categories: non-optical methods and optical methods. Non-optical measurement methods include scanning tunneling microscopy and atomic force microscopy. The lateral resolution of scanning tunneling microscopy is 0.1nm, and the axial resolution is on the order of 0.01nm , its axial and lateral measurement range is small (about 1 μm), and the scanning tunneling microscope reflects the surface morphology of the measured surface through the tunnel current. Therefore, it can only measure conductors or semiconductors, and the measurement must be carried out in a vacuum. The axial resolution of the atomic force microscope reaches 0.1nm, and the lateral resolution is about 10nm. It can detect both conductors and non-conductors, but has the disadvantages of small imaging range and great influence by the probe. Nanoscale optical measurement methods are divided into two categories: (1) chromatic confocal spectroscopy (CCS), which combines chromatic aberration and confocal microscopy, (2) interferometric methods, including: monochromatic light phase-shifting interferometry ( Phase-shifting interferometry (PSI), Vertical scanning white-light interferometry (SWLI), White-light spectral interferometry (WLSI) and heterodyne interferometry (Heterodyne interferometry, HI).
轴向分辨率、轴向测量范围、系统稳定性、横向分辨率及检测速度是纳米级形貌成像中比较关键的问题。CCS轴向分辨率达到2nm，差于干涉方法，但是CCS的优点是高稳定性。CCS的另一缺点是其轴向分辨率、轴向测量范围及横向分辨率都决定于样品光焦点，轴向分辨率、轴向测量范围依赖于焦点色散特性，因此，要求焦点色散特性严格稳定，不适合于进行快速的光学扫描，目前都是用高精度平移台移动样品进行二维扫描，机械扫描会引入振动干扰，影响轴向测量精度，同时也限制了测量速度。对于干涉方法，影响系统性能的主要因素是稳定性和轴向测量范围，干涉方法具有高灵敏度，但对外界的干扰也同样灵敏，干涉方法的轴向精度和横向分辨率无关，可以实现快速的光学扫描。Axial resolution, axial measurement range, system stability, lateral resolution and detection speed are key issues in nanoscale topography imaging. The axial resolution of CCS reaches 2nm, which is worse than the interference method, but the advantage of CCS is high stability. Another disadvantage of CCS is that its axial resolution, axial measurement range and lateral resolution are all determined by the light focus of the sample. The axial resolution and axial measurement range depend on the focal dispersion characteristics. Therefore, the focal dispersion characteristics are required to be strictly stable. , is not suitable for fast optical scanning. At present, a high-precision translation stage is used to move the sample for two-dimensional scanning. Mechanical scanning will introduce vibration interference, which will affect the axial measurement accuracy and limit the measurement speed. For the interferometric method, the main factors affecting the system performance are stability and axial measurement range. The interferometric method has high sensitivity, but it is also sensitive to external interference. The axial precision of the interferometric method has nothing to do with the lateral resolution, and can achieve fast optical scanning.
干涉法的轴向分辨率要高于CCS，但是干涉法存在相位包裹及易受环境干扰的问题。PSI、WLSI及HI是通过计算参考光和样品光之间的相位差得到样品表面的高度值，相位计算的主值范围为[-π，+π]，当相位超过[-π，+π]，发生相位包裹，必须通过相位解包裹恢复真实相位，才能得到正确的高度信息。目前，虽然已有多种数值相位解包裹的方法被提出，然而这些方法都存在一定的问题，计算复杂耗时，受噪声及欠采样影响，特别是当相邻两点相位差超过π时，无法恢复真实的相位。相位解包裹的原理是根据相位的连续性，通过比较相邻两点之间相位差进行相位解包裹，从原理上讲，当相邻两点的相位差大于π时，就无法正确恢复真实相位，这就限定了干涉法的应用范围。SWLI可以测量绝对光程，不存在相位包裹问题，但是对于每一探测点，需要进行轴向扫描，干涉条纹的解调精度和轴向扫描精度限制了轴向测量精度，同时使用轴向扫描也限制了测量速度。The axial resolution of interferometry is higher than that of CCS, but interferometry has the problems of phase wrapping and susceptibility to environmental interference. PSI, WLSI and HI obtain the height value of the sample surface by calculating the phase difference between the reference light and the sample light. The main value range of the phase calculation is [-π, +π], when the phase exceeds [-π, +π] , phase wrapping occurs, and the real phase must be restored through phase unwrapping to obtain the correct height information. At present, although a variety of numerical phase unwrapping methods have been proposed, these methods have certain problems, such as complex and time-consuming calculations, and are affected by noise and undersampling, especially when the phase difference between two adjacent points exceeds π, Unable to restore true phase. The principle of phase unwrapping is to perform phase unwrapping by comparing the phase difference between two adjacent points based on the continuity of the phase. In principle, when the phase difference between two adjacent points is greater than π, the true phase cannot be restored correctly. , which limits the scope of application of the interferometric method. SWLI can measure the absolute optical distance without the phase wrapping problem, but for each detection point, axial scanning is required, the demodulation accuracy of the interference fringe and the axial scanning accuracy limit the axial measurement accuracy, and the use of axial scanning also The measurement speed is limited.
发明内容：Invention content:
本发明的目的是为了克服上述现有技术的缺点，提供一种测量精度高、受环境干扰以及机械干扰小的物品表面形貌检测方法及装置。The object of the present invention is to overcome the above-mentioned shortcomings of the prior art, and provide a method and device for detecting the surface topography of an object with high measurement accuracy and little environmental and mechanical interference.
本发明的发明目的可以通过以下的技术方案来实现：一种物品表面形貌检测方法，检测过程如下：The purpose of the invention of the present invention can be realized by the following technical solutions: a method for detecting surface topography of an article, the detection process is as follows:
①由低相干光源产生低相干光线，低相干光线射进三端环形器的端口1，然后从端口2射出；① Low coherence light is generated by a low coherence light source, and the low coherence light enters port 1 of the three-terminal circulator, and then exits port 2;
②从端口2射出的光线经第一透镜准直后射进x-y扫描振镜中的x振镜，然后从x振镜射到y振镜，接着从y振镜射出；② The light emitted from port 2 is collimated by the first lens and then enters the x galvanometer in the x-y scanning galvanometer, then shoots from the x galvanometer to the y galvanometer, and then exits from the y galvanometer;
③从y振镜射出的光线经第二透镜聚焦，聚焦后的光线经过一分光片后分为两部分光线，一部分从玻璃底面反射，作为参考光，另一部分穿透玻璃后投射到被样品表面，然后反射，作为样品光；③The light emitted from the y-galvanometer is focused by the second lens, and the focused light is divided into two parts after passing through a beam splitter, one part is reflected from the bottom of the glass as a reference light, and the other part penetrates the glass and is projected onto the surface of the sample , and then reflected as sample light;
④从③中发射的两部分光线共光路返回，经第二透镜汇聚到扫描振镜的y振镜，经y振镜射入x振镜，然后射出；④The two parts of light emitted from ③ return to the common optical path, converge to the y galvanometer of the scanning galvanometer through the second lens, enter the x galvanometer through the y galvanometer, and then exit;
⑤x振镜射出的光线经第一透镜汇聚进入三端环形器的端口2，然后从端口3射出；⑤ The light emitted by the x galvanometer is converged by the first lens into port 2 of the three-terminal circulator, and then emitted from port 3;
⑥从端口3射出的参考光和样品光进入光谱仪，光谱仪传递数据给电脑；⑥The reference light and sample light emitted from port 3 enter the spectrometer, and the spectrometer transmits data to the computer;
⑦控制扫描振镜的运动，扫描振镜对样品进行逐点扫描，电脑获得样品表面各个位置的低相干光干涉光谱；⑦Control the movement of the scanning galvanometer, the scanning galvanometer scans the sample point by point, and the computer obtains the low-coherence light interference spectrum at each position on the sample surface;
⑧电脑计算相邻位置的相位差 ⑧The computer calculates the phase difference between adjacent positions
⑨根据相位差计算样品该相邻两位置的深度差Δz，得到样品表面形貌的相位差分图；⑨Based on phase difference Calculate the depth difference Δz between two adjacent positions of the sample to obtain the phase difference map of the surface topography of the sample;
⑩对计算的深度差Δz进行积分，得到最终样品表面形貌的定量分布情况。⑩ Integrate the calculated depth difference Δz to obtain the quantitative distribution of the surface topography of the final sample.
步骤⑧中所属的计算相邻位置的相位差的步骤如下：The step of calculating the phase difference of adjacent positions belonging to step 8 is as follows:
相邻两位置点1和2的相干光谱分别为:The coherent spectra of two adjacent points 1 and 2 are respectively:
位置点1的相干光谱为： The coherent spectrum of position point 1 is:
位置点2的相干光谱为： The coherence spectrum of position point 2 is:
其中，I1(km)、I2(km)分别为位置点1、2的相干光谱，S(km)为光源光谱强度分布，A11、A12分别为位置1对应的样品光和参考光振幅，A21、A22分别为位置2对应的样品光和参考光振幅，km为波数，n为空气折射率，样品面和参考面的距离用不同分辨率的两部分表示，相邻两位置点1和2的相干光谱表达式中z0表示样品面和参考面的绝对距离，其精度决定于光源的相干长度，相对于z0的具有亚相干长度分辨率的距离为kc为光源的中心波数，其精度决定于光谱仪的光谱分辨率。Among them, I 1 ( km ) and I 2 ( km ) are the coherent spectra of positions 1 and 2 respectively, S( km ) is the spectral intensity distribution of the light source, and A 11 and A 12 are the sample light corresponding to position 1 and the reference light amplitude, A 21 and A 22 are the sample light and reference light amplitude corresponding to position 2 respectively, km is the wave number, n is the air refractive index, the distance between the sample surface and the reference surface is represented by two parts with different resolutions, In the coherent spectrum expression of two adjacent positions 1 and 2, z 0 represents the absolute distance between the sample surface and the reference surface, and its accuracy depends on the coherence length of the light source. The distance with sub-coherence length resolution relative to z 0 is kc is the central wavenumber of the light source, and its accuracy depends on the spectral resolution of the spectrometer.
假定位置点2相对于点1的微小高度增量为Δz0，位置点1和2的参考臂光程相等，则位置点1和2的高度差Δz0为，Assuming that the slight height increment of point 2 relative to point 1 is Δz 0 , and the reference arm optical paths of points 1 and 2 are equal, then the height difference Δz 0 between point 1 and 2 is,
为与之差 for and Difference
对I1(km)和I2(km)分别进行傅立叶变换后得到相对应的复数序列F1(2nzm)和F2(2nzm)，zm表示离散化的高度。因为样品中只有样品表面为反射面，则F1(2nzm)和F2(2nzm)的功率谱极大值对应的位置即为2nz0，因此得到两个复数和则为，The corresponding complex number sequences F 1 (2nz m ) and F 2 (2nz m ) are obtained after performing Fourier transform on I 1 (k m ) and I 2 (k m ), respectively, where z m represents the height of discretization. Because only the sample surface is a reflective surface in the sample, the position corresponding to the maximum value of the power spectrum of F 1 (2nz m ) and F 2 (2nz m ) is 2nz 0 , so two complex numbers are obtained with but for,
上式中星号表示复共轭，由此式计算出相位差即得到样品表面的相位差分图，不论各点的相位值大小，只要相邻两点在区间[-π，+π]，不发生相位包裹，当相邻两点的相位差超过π，在相位差分图上出现相位包裹，通过相位解包裹处理，消除相位差分图上的相位包裹，再进行积分，得到样品表面的相位分布及形貌。由于解包裹运算是在相位差分图上进行的，因此，把相邻两点相位差绝对值的限制条件由目前的π扩大到2π。The asterisk in the above formula indicates the complex conjugate, and the phase difference is calculated from this formula That is, to obtain the phase difference diagram of the sample surface, regardless of the phase value of each point, as long as two adjacent points are in the interval [-π, +π], phase wrapping does not occur. When the phase difference between two adjacent points exceeds π, in the phase Phase wrapping appears on the difference map. Through phase unwrapping processing, the phase wrapping on the phase difference map is eliminated, and then integrated to obtain the phase distribution and morphology of the sample surface. Since the unwrapping operation is performed on the phase difference graph, the restriction on the absolute value of the phase difference between two adjacent points is expanded from the current π to 2π.
步骤⑨中，根据所述的相位差获得位置1与位置2的深度差Δz，具体通过以下方式获得：In step ⑨, according to the phase difference Obtain the depth difference Δz between position 1 and position 2, specifically through the following methods:
包括有低相干光源、三端环形器、第一透镜、扫描振镜、第二透镜和分光片，三端环形器的端口1与低相干光源相连通，端口2后续依次连接第一透镜—x-y扫描振镜—第二透镜，端口3依次连接光谱仪—电脑，第一透镜与x-y扫描振镜的x振镜相连，第二透镜与x-y扫描振镜的y振镜相连，分光片设置在第二透镜与y振镜相连一侧的另一侧，分光片上第二透镜一侧的另一侧镀上一层透光率为50％～70％的反射膜，分光片镀上反射膜的一侧设有提供给被样品放置的样品台。It includes a low-coherence light source, a three-terminal circulator, a first lens, a scanning galvanometer, a second lens, and a beam splitter. Port 1 of the three-terminal circulator is connected to a low-coherence light source, and port 2 is subsequently connected to the first lens—x-y Scanning galvanometer - the second lens, port 3 is connected to the spectrometer - computer in turn, the first lens is connected to the x galvanometer of the x-y scanning galvanometer, the second lens is connected to the y galvanometer of the x-y scanning galvanometer, and the beam splitter is set on the second The other side of the side where the lens is connected to the y vibrating mirror, the other side of the second lens on the beam splitter is coated with a reflective film with a light transmittance of 50% to 70%, and the side of the beam splitter coated with a reflective film There is a sample table provided for the sample to be placed.
在第一透镜和x-y扫描振镜之间设置一反射镜。A mirror is arranged between the first lens and the x-y scanning galvanometer.
采用本技术方案后，与现有技术相比，本技术方案具有以下优点：本发明能够实现表面形貌高精度的快速非接触测量，系统结构简单，成本较低，测量精度能达到亚nm级，由于不直接计算各个位置的相位，因此，只要相邻两点的相位差在区间[-π，+π]，不发生相位包裹，将干涉法相邻两点相位差绝对值的限制条件由目前的π扩大到2π。参考面和样品置于同一平台之上，最大限度消除环境干扰及系统振动的影响，提高了系统稳定性，使用光学扫描实现高速成像，减小机械扫描引入的干扰。After adopting this technical solution, compared with the prior art, this technical solution has the following advantages: the present invention can realize fast non-contact measurement of surface topography with high precision, the system structure is simple, the cost is low, and the measurement accuracy can reach sub-nm level , since the phase of each position is not directly calculated, so as long as the phase difference between two adjacent points is in the interval [-π, +π], phase wrapping does not occur. The current π is expanded to 2π. The reference surface and the sample are placed on the same platform to minimize the impact of environmental interference and system vibration, improve system stability, use optical scanning to achieve high-speed imaging, and reduce interference introduced by mechanical scanning.
附图说明：Description of drawings:
图1是本发明物品表面形貌检测装置的结构图。Fig. 1 is a structural diagram of the object surface topography detection device of the present invention.
具体实施方式：detailed description:
下面结合附图对本技术作进一步说明。The technology will be further described below in conjunction with the accompanying drawings.
物品表面形貌检测装置，包括：低相干光源1、光谱仪、三端环形器2、第一透镜3、反射镜5、x-y扫描振镜6、第二透镜7和样品台12。低相干光源1发出的光由三端环形器2的端口1进入，从三端环形器2的端口2出来的光经透镜3准直后射到反射镜5，改变方向后的光射到x-y扫描振镜6的x振镜，从x振镜射到x-y扫描振镜6的y振镜，经y振镜的光被第二透镜7聚焦到被测样品9表面，通过扫描振镜6的快速转动，实现对样品9表面的扫描。样品和作为参考反射镜的分光片8置于同一平台之上，样品臂和参考臂为共光路。在样品台12上放一小立柱4，在小立柱4上放一分光片8该分光片底部上镀上一层透光率为50％—70％的反射膜，被第二透镜7聚焦的光一部分被分光片8下表面反射，另一部分穿过分光片8被聚焦到样品9表面，被样品9表面反射的样品光与被分光片8下表面反射的参考光通过第二透镜7汇聚到扫描振镜6的y振镜，经y振镜射入x振镜的光通过反射镜5改变方向后，由透镜3汇聚到三端环形器2的端口2，从三端环形器2的端口3进入光谱仪10的准直透镜13，经准直透镜13准直的光射入透射光栅14(1145lines/mm,Wasatch Photonics)后被第三透镜15聚焦到高速线阵相机16(GL2048L,Sensors Unlimited)，参考光和样品光形成的干涉光谱被光谱仪10实时采集,干涉光谱传给电脑11进行后续处理。The object surface topography detection device includes: a low-coherence light source 1, a spectrometer, a three-terminal circulator 2, a first lens 3, a mirror 5, an x-y scanning galvanometer 6, a second lens 7 and a sample stage 12. The light emitted by the low-coherence light source 1 enters through the port 1 of the three-terminal circulator 2, and the light coming out of the port 2 of the three-terminal circulator 2 is collimated by the lens 3 and then hits the reflector 5, and the light after changing the direction hits x-y The x vibrating mirror of the scanning vibrating mirror 6 is shot from the x vibrating mirror to the y vibrating mirror of the x-y scanning vibrating mirror 6, and the light passing through the y vibrating mirror is focused by the second lens 7 onto the surface of the sample 9 to be measured, and passed through the scanning vibrating mirror 6 Rotate quickly to realize the scanning of the surface of the sample 9. The sample and the beam splitter 8 as a reference reflector are placed on the same platform, and the sample arm and the reference arm share a common optical path. Put a small column 4 on the sample stage 12, and place a spectroscopic sheet 8 on the small column 4. The bottom of the spectroscopic sheet is coated with a reflective film with a light transmittance of 50%-70%, which is focused by the second lens 7. Part of the light is reflected by the lower surface of the spectroscopic sheet 8, and the other part passes through the spectroscopic sheet 8 and is focused onto the surface of the sample 9. The sample light reflected by the surface of the sample 9 and the reference light reflected by the lower surface of the spectroscopic sheet 8 converge to the Scanning the y galvanometer of the galvanometer 6, the light injected into the x galvanometer through the y galvanometer passes through the reflector 5 and changes its direction, and is converged by the lens 3 to the port 2 of the three-terminal circulator 2, and from the port 2 of the three-terminal circulator 2 3 Enter the collimator lens 13 of the spectrometer 10, the light collimated by the collimator lens 13 enters the transmission grating 14 (1145lines/mm, Wasatch Photonics) and is focused by the third lens 15 to a high-speed line scan camera 16 (GL2048L, Sensors Unlimited ), the interference spectrum formed by the reference light and the sample light is collected in real time by the spectrometer 10, and the interference spectrum is transmitted to the computer 11 for subsequent processing.
扫描振镜6的y转轴位置为第二透镜7的焦点。通过扫描振镜6的快速转动，实现对样品9表面的扫描。The y-axis position of the scanning galvanometer 6 is the focal point of the second lens 7 . The scanning of the surface of the sample 9 is realized through the rapid rotation of the scanning galvanometer 6 .
本发明是一种达到亚纳米级表面形貌检测的方法，包括以下步骤：The invention is a method for detecting sub-nanometer surface topography, comprising the following steps:
S1，使用共光路的频域低相干光干涉装置，分光片8(该分光片上渡50％—70％反射膜)放在样品台12上，采集分光片8下表面的反射光与样品表面反射光的干涉光谱，用x-y扫描振镜6对样品进行逐点扫描，得到样品表面各个位置的低相干光干涉光谱。S1, using a frequency-domain low-coherence optical interference device with a common optical path, the spectroscopic sheet 8 (50%-70% reflective film on the spectroscopic sheet) is placed on the sample stage 12, and the reflected light from the lower surface of the spectroscopic sheet 8 and the reflection from the sample surface are collected. For the interference spectrum of light, use the x-y scanning galvanometer 6 to scan the sample point by point to obtain the low-coherence light interference spectrum at each position on the sample surface.
S2，计算相邻位置的相位差 S2, calculate the phase difference of adjacent positions
S3，根据所述的相位差计算样品该相邻两位置的深度差Δz，得到表面形貌的相位差分图；S3, according to the phase difference Calculate the depth difference Δz between the two adjacent positions of the sample to obtain the phase difference diagram of the surface topography;
S4，对计算的深度差Δz进行积分，得到样品表面形貌的定量分布。S4, integrating the calculated depth difference Δz to obtain a quantitative distribution of the surface topography of the sample.
步骤S2中所述的计算相邻位置的相位差的步骤如下：The steps of calculating the phase difference of adjacent positions described in step S2 are as follows:
相邻两位置点1和2的相干光谱分别为:The coherent spectra of two adjacent points 1 and 2 are respectively:
位置点1的相干光谱为： The coherent spectrum of position point 1 is:
位置点2的相干光谱为： The coherence spectrum of position point 2 is:
其中，I1(km)、I2(km)分别为位置点1、2的相干光谱，S(km)为光源光谱强度分布，A11、A12分别为位置1对应的样品光和参考光振幅，A21、A22分别为位置2对应的样品光和参考光振幅，km为波数，n为空气折射率，样品面和参考面的距离用不同分辨率的两部分表示，相邻两位置点1和2的相干光谱表达式中z0表示样品面和参考面的绝对距离，其精度决定于光源的相干长度，相对于z0的具有亚相干长度分辨率的距离为kc为光源的中心波数，其精度决定于光谱仪的光谱分辨率。Among them, I 1 ( km ) and I 2 ( km ) are the coherent spectra of positions 1 and 2 respectively, S( km ) is the spectral intensity distribution of the light source, and A 11 and A 12 are the sample light corresponding to position 1 and the reference light amplitude, A 21 and A 22 are the sample light and reference light amplitude corresponding to position 2 respectively, km is the wave number, n is the air refractive index, the distance between the sample surface and the reference surface is represented by two parts with different resolutions, In the coherent spectrum expression of two adjacent positions 1 and 2, z 0 represents the absolute distance between the sample surface and the reference surface, and its accuracy depends on the coherence length of the light source. The distance with sub-coherence length resolution relative to z 0 is kc is the central wavenumber of the light source, and its accuracy depends on the spectral resolution of the spectrometer.
假定位置点2相对于点1的微小高度增量为Δz0，置点1和2的参考臂光程相等，则位置点1和2的高度差Δz0为，Assuming that the slight height increment of point 2 relative to point 1 is Δz 0 , and the reference arm optical paths of point 1 and 2 are equal, then the height difference Δz 0 between point 1 and point 2 is,
公式(3)中，为与之差。对I1(km)和I2(km)分别进行傅立叶变换后得到相对应的复数序列F1(2nzm)和F2(2nzm)，zm表示离散化的高度。因为样品中只有样品表面为反射面，则F1(2nzm)和F2(2nzm)的功率谱极大值对应的位置即为2nz0，因此得到两个复数和则为，In formula (3), for and Difference. The corresponding complex number sequences F 1 (2nz m ) and F 2 (2nz m ) are obtained after performing Fourier transform on I 1 (k m ) and I 2 (k m ), respectively, where z m represents the height of discretization. Because only the sample surface is a reflective surface in the sample, the position corresponding to the maximum value of the power spectrum of F 1 (2nz m ) and F 2 (2nz m ) is 2nz 0 , so two complex numbers are obtained with but for,
上式中星号表示复共轭，由(4)式计算出相位差即得到样品表面的相位差分图，不论各点的相位值大小，只要相邻两点在区间[-π，+π]，不发生相位包裹，当相邻两点的相位差超过π，在相位差分图上出现相位包裹，通过相位解包裹处理，消除相位差分图上的相位包裹，再进行积分，得到样品表面的相位分布及形貌。由于解包裹运算是在相位差分图上进行的，因此，把相邻两点相位差绝对值的限制条件由目前的π扩大到2π。The asterisk in the above formula indicates complex conjugate, and the phase difference is calculated by formula (4) That is, to obtain the phase difference diagram of the sample surface, regardless of the phase value of each point, as long as two adjacent points are in the interval [-π, +π], phase wrapping does not occur. When the phase difference between two adjacent points exceeds π, in the phase Phase wrapping appears on the difference map. Through phase unwrapping processing, the phase wrapping on the phase difference map is eliminated, and then integrated to obtain the phase distribution and morphology of the sample surface. Since the unwrapping operation is performed on the phase difference graph, the restriction on the absolute value of the phase difference between two adjacent points is expanded from the current π to 2π.
步骤S3中，根据所述的相位差获得位置1与位置2的深度差Δz具体通过以下方式获得： In step S3, according to the phase difference Obtain the depth difference Δz between position 1 and position 2 through the following methods:
对所述的深度差Δz进行积分，得到被检测样品表面形貌定量分布：z＝∫Δz。The depth difference Δz is integrated to obtain the quantitative distribution of the surface topography of the tested sample: z=∫Δz.
以上所述，仅是本发明的较佳实施例而已，并非对本发明作任何形式上的限制。任何熟悉本领域的技术人员，在不脱离本发明技术方案范围情况下，都可利用上述揭示的方法和技术内容对本发明技术方案作出许多可能的变动和修饰，或修改为等同变化的等效实施例。故凡是未脱离本发明技术方案的内容，依据本发明之形状、构造及原理所作的等效变化，均应涵盖于本发明的保护范围内。The above descriptions are only preferred embodiments of the present invention, and do not limit the present invention in any form. Any person familiar with the art, without departing from the scope of the technical solution of the present invention, can use the methods and technical content disclosed above to make many possible changes and modifications to the technical solution of the present invention, or modify it into an equivalent implementation of equivalent changes example. Therefore, all equivalent changes made according to the shape, structure and principle of the present invention that do not deviate from the technical solution of the present invention shall fall within the scope of protection of the present invention.
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Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107796333A (en) * | 2017-11-20 | 2018-03-13 | 北京航空航天大学 | A kind of optical tomography system based on scanning galvanometer |
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010256192A (en) * | 2009-04-25 | 2010-11-11 | Utsunomiya Univ | Shape measuring method and shape measuring device by phase shift method, complex amplitude measuring method and complex amplitude measuring device |
| CN101995227A (en) * | 2010-09-29 | 2011-03-30 | 哈尔滨工程大学 | Optical path autocorrelator for distributed optical fiber strain sensing measurement |
| CN102052902A (en) * | 2010-12-10 | 2011-05-11 | 天津大学 | High-precision wide-range low-coherent interference shift demodulation device and demodulation method thereof |
| CN104160294A (en) * | 2012-03-01 | 2014-11-19 | 莱卡地球系统公开股份有限公司 | Method for determining a change in distance by means of interferometry |
| CN104197844A (en) * | 2014-09-18 | 2014-12-10 | 中国工程物理研究院流体物理研究所 | All optical fiber frequency domain interference absolute distance measurement method and device |
| CN104215176A (en) * | 2014-09-17 | 2014-12-17 | 中国科学院上海光学精密机械研究所 | High accuracy optical interval measurement device and method |
| CN104296698A (en) * | 2014-10-27 | 2015-01-21 | 广州飞拓优视光电科技有限公司 | Method for measuring evenness of optical surface with ultrahigh precision |
| CN105300326A (en) * | 2015-11-30 | 2016-02-03 | 东北大学 | Method and device for quantitative determination of paint surface flatness |
| CN205844136U (en) * | 2016-07-22 | 2016-12-28 | 浙江大学 | A kind of optical detection apparatus of particle shape |
-
2017
- 2017-05-03 CN CN201710304285.1A patent/CN107144235A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010256192A (en) * | 2009-04-25 | 2010-11-11 | Utsunomiya Univ | Shape measuring method and shape measuring device by phase shift method, complex amplitude measuring method and complex amplitude measuring device |
| CN101995227A (en) * | 2010-09-29 | 2011-03-30 | 哈尔滨工程大学 | Optical path autocorrelator for distributed optical fiber strain sensing measurement |
| CN102052902A (en) * | 2010-12-10 | 2011-05-11 | 天津大学 | High-precision wide-range low-coherent interference shift demodulation device and demodulation method thereof |
| CN104160294A (en) * | 2012-03-01 | 2014-11-19 | 莱卡地球系统公开股份有限公司 | Method for determining a change in distance by means of interferometry |
| CN104215176A (en) * | 2014-09-17 | 2014-12-17 | 中国科学院上海光学精密机械研究所 | High accuracy optical interval measurement device and method |
| CN104197844A (en) * | 2014-09-18 | 2014-12-10 | 中国工程物理研究院流体物理研究所 | All optical fiber frequency domain interference absolute distance measurement method and device |
| CN104296698A (en) * | 2014-10-27 | 2015-01-21 | 广州飞拓优视光电科技有限公司 | Method for measuring evenness of optical surface with ultrahigh precision |
| CN105300326A (en) * | 2015-11-30 | 2016-02-03 | 东北大学 | Method and device for quantitative determination of paint surface flatness |
| CN205844136U (en) * | 2016-07-22 | 2016-12-28 | 浙江大学 | A kind of optical detection apparatus of particle shape |
Cited By (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107796333A (en) * | 2017-11-20 | 2018-03-13 | 北京航空航天大学 | A kind of optical tomography system based on scanning galvanometer |
| CN107796333B (en) * | 2017-11-20 | 2020-04-24 | 北京航空航天大学 | Optical tomography system based on scanning galvanometer |
| CN108662986A (en) * | 2018-03-07 | 2018-10-16 | 温州医科大学 | A kind of free form surface on-line real-time measuremen method and device |
| CN110361099A (en) * | 2019-07-17 | 2019-10-22 | 东北大学 | A Spectral-Domain Low-Coherent Optical Interference Optical Path Difference Demodulation Method |
| CN110361099B (en) * | 2019-07-17 | 2020-08-25 | 东北大学 | A spectral-domain low-coherence optical path difference demodulation method |
| US11243067B2 (en) | 2020-02-24 | 2022-02-08 | Yangtze Memory Technologies Co., Ltd. | Systems and methods for semiconductor chip surface topography metrology |
| WO2021168613A1 (en) * | 2020-02-24 | 2021-09-02 | Yangtze Memory Technologies Co., Ltd. | Systems and methods for semiconductor chip surface topography metrology |
| US11448499B2 (en) | 2020-02-24 | 2022-09-20 | Yangtze Memory Technologies Co., Ltd. | Systems and methods for semiconductor chip surface topography metrology |
| US11454491B2 (en) | 2020-02-24 | 2022-09-27 | Yangtze Memory Technologies Co., Ltd. | Systems having light source with extended spectrum for semiconductor chip surface topography metrology |
| US11562919B2 (en) | 2020-02-24 | 2023-01-24 | Yangtze Memory Technologies Co., Ltd. | Systems and methods for semiconductor chip surface topography metrology |
| US11796307B2 (en) | 2020-02-24 | 2023-10-24 | Yangtze Memory Technologies Co., Ltd. | Systems and methods for semiconductor chip surface topography metrology |
| CN113483679A (en) * | 2021-07-06 | 2021-10-08 | 东北大学秦皇岛分校 | Contact lens parameter measuring device and method |
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| CN115451863A (en) * | 2022-08-22 | 2022-12-09 | 中国电子科技集团公司第十四研究所 | Laser measuring system for complex structure and profile antenna radiation unit |
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