公开(公告)号：US5302829A

公开(公告)日：1994-04-12

申请号：US003472

申请日：1993-01-12

申请人： Fumio Komatsu ,  Yasuhiro Kaga

发明人： Fumio Komatsu ,  Yasuhiro Kaga

IPC分类号： H01J37/147 ,  H01J37/21 ,  H01J37/28 ,  H01J37/26

CPC分类号： H01J37/28 ,  H01J37/21

摘要： An automatic focusing method for scanning electron microscopy. A scanning electron microscope is set in a low magnification mode to detect a taper portion of an object to be observed. The beam scanning whose direction is perpendicular to the taper portion is effected whenever objective lens control condition is changed at a first pitch, and the secondary electron signals obtained under these conditions are converted into video signals. The video signals are differential smoothed to calculate a sum of video signal absolute values. On the basis of the sum of the absolute values, an optimum objective lens control condition in the low magnification mode can be obtained. Sequentially, the microscope is set to a high magnification mode, and the objective lens control condition is further changed at a second pitch within a predetermined range with the optimum control condition in the low magnification mode as the center of the range. The beam scanning whose direction is perpendicular to the taper portion is effected. In the same way as in the low magnification mode, the secondary electrons signal obtained under these conditions are converted into video signals to obtain the optimum objective lens control condition in the high magnification mode. The optimum control condition obtained in the high magnification mode is determined as the control condition to determine the focal distance of the objective lens.

摘要翻译： 一种扫描电子显微镜的自动对焦方法。 将扫描型电子显微镜设定为低倍率模式，以检测被观察物体的锥形部分。 当物镜控制条件以第一节距改变时，其方向垂直于锥形部分的光束扫描实现，并且在这些条件下获得的二次电子信号被转换为视频信号。 视频信号被差分平滑以计算视频信号绝对值之和。 基于绝对值的和，可以获得低倍率模式下的最佳物镜控制条件。 接着，将显微镜设定为高放大倍数模式，并且以低放大倍数模式的最佳控制条件为范围，以预定范围内的第二间距进一步改变物镜控制条件。 实现了与锥形部分垂直的光束扫描。 以与低倍率模式相同的方式，在这些条件下获得的二次电子信号被转换为视频信号，以在高倍率模式下获得最佳物镜控制条件。 确定在高倍率模式下获得的最佳控制条件作为确定物镜焦距的控制条件。

公开(公告)号：US5159643A

公开(公告)日：1992-10-27

申请号：US651795

申请日：1991-02-07

申请人： Yasuhiro Kaga ,  Fumio Komatsu

发明人： Yasuhiro Kaga ,  Fumio Komatsu

IPC分类号： G01Q80/00 ,  G01B15/00

CPC分类号： G01B15/00

摘要： A pattern dimension measuring method for measuring the dimension of a measuring portion of a pattern of a specimen placed on a specimen stage by controlling a deflector of a scan type electron microscope capable of setting a desired inclination angle of the specimen stage a lens barrel, applying an electron beam to the measuring portion of the specimen, and image processing a secondary electron signal from the measuring portion, the method comprising: a first step of calculating the distance between top edges of the measuring portion of the pattern by image processing the secondary electron signal when the electron beam is applied to the measuring portion at an inclination angle of zero; a second step of obtaining the number of pixels at a taper portion of the measuring portion of the pattern by image processing the secondary electron signal when the electron beam is applied to the measuring portion at a first predetermined inclination angle which allows to observe the bottom edges; a third step of obtaining the number of pixels at the taper portion by image processing the secondary electron signal when the electron beam is applied to the measuring portion at a second predetermined inclination angle different from the first inclination angle which allows to observe the bottom edges; a fourth step of calculating the taper angle and height of the pattern in accordance with the numbers of pixels of the taper portion obtained at the second and third steps and the first and second predetermined inclination angles; and a fifth step of calculating the distance between the bottom edges of the pattern and the difference ratio between the top edge and bottom edge distances in accordance with the results calculated at the fourth step.

公开(公告)号：US5161201A

公开(公告)日：1992-11-03

申请号：US651796

申请日：1991-02-07

申请人： Yasuhiro Kaga ,  Kei Hattori ,  Isahiro Hasegawa ,  Fumio Komatsu

发明人： Yasuhiro Kaga ,  Kei Hattori ,  Isahiro Hasegawa ,  Fumio Komatsu

IPC分类号： G01Q30/02 ,  G01B15/00 ,  G01Q30/04

CPC分类号： G01B15/00

摘要： A pattern profile measuring method and apparatus for measuring the profile of a measuring portion of a pattern of a specimen placed on a specimen stage by controlling a deflector of a scanning electron microscope capable of setting a desired inclination angle of one of the specimen stage and an electron optical column, applying an electron beam to the measuring portion of the specimen, and image processing a secondary electron signal from the measuring portion. The method comprises: a first step of calculating the distance at the bottom portion of the measuring portion of the pattern by image processing the secondary electron signal when the electron beam is applied to the measuring portion at an inclination angle of zero; a second step of obtaining the number of pixels at a taper portion of the measuring portion of the pattern by image processing the secondary electron signal when the electron beam is applied to the measuring portion at a first predetermined inclination angle; a third step of obtaining the number of pixels at the taper portion by image processing the secondary electron signal when the electron beam is applied to the measuring portion at a second predetermined inclination angle different from the first inclination angle; a fourth step of calculating the taper angle and depth of the pattern in accordance with the numbers of pixels of the taper portion obtained at the second and third steps and the first and second predetermined inclination angles; and a fifth step of obtaining the profile of the taper portion in accordance with the strength change of the secondary electron signal from the taper portion.

公开(公告)号：US4894540A

公开(公告)日：1990-01-16

申请号：US257557

申请日：1988-10-14

申请人： Fumio Komatsu

发明人： Fumio Komatsu

IPC分类号： H01J37/244 ,  G01B15/00 ,  G01N23/225 ,  H01J37/22 ,  H01J37/252 ,  H01J37/28 ,  H01L21/027 ,  H01L21/66 ,  H04N1/409

CPC分类号： H01J37/28

摘要： An image forming method includes a first step of irradiating a beam onto an object, and using an intensity corresponding to an image area onto which the beam was irradiated as an intensity of a pixel at the center of the image area, and scanning a beam throughout the inspection area of the object to obtain an image within the inspection area as a collection of pixels arranged at intervals smaller than a beam diameter; and a second step of assigning a pixel to be processed and neighboring pixels with coefficients in accordance with a beam intensity distribution, multiplying the intensity of each pixel by each assigned coefficient, determining a new intensity of the pixel to be processed in accordance with the sum of respective products, and repeating the new intensity determining process for all pixels necessary to be processed. In the second step, the value of the coefficients for those pixels except on the scanning direction may be reduced. Further, a third step may be provided for linearly-transforming the intensities so as to make the intensities of respective pixels to be distributed within a predetermined range.

公开(公告)号：US4807159A

公开(公告)日：1989-02-21

申请号：US897429

申请日：1986-08-18

申请人： Fumio Komatsu ,  Motosuke Miyoshi ,  Katsuya Okumura

发明人： Fumio Komatsu ,  Motosuke Miyoshi ,  Katsuya Okumura

IPC分类号： G21K5/04 ,  G01R31/26 ,  G01R31/305 ,  H01J37/04 ,  H01J37/28 ,  H01L21/027 ,  G01N23/00 ,  G21K1/08

CPC分类号： G01R31/305

摘要： Before detecting the surface state of specific patterns a sample by means of an electron beam tester system, patterns formed in a specified surface area of the sample, are detected by deflecting an electron beam by a deflection coil. Data representing current supplied to the deflection coil, data representing the position of the sample during the pattern-detecting operation, and image signals representing the patterns found in the specified surface area, are stored in a memory. While the specific patterns of a sample are being detected, the electron beam is used to perform a second pattern-detecting operation. Data representing current supplied to the deflection coil during the second pattern-detecting operation, such data representing the position of the sample, and image signals provided by the second pattern-detecting operation representing the patterns formed in the specified surface area, afe compared with those data items already stored in the memory. From the difference between the compared two sets of data items, any drift in the electron beam is calculated. In accordance with the drift thus calculated, the deflection coil is energized to deflec the electron beam such that the beam is applied onto the desired portion of the sample.

摘要翻译： 在通过电子束测试仪系统检测特定图案的表面状态之前，通过偏转线圈偏转电子束来检测在样品的规定表面积中形成的图案。 表示提供给偏转线圈的电流的数据，表示图案检测操作期间的样品的位置的数据和表示在指定表面积中发现的图案的图像信号被存储在存储器中。 当正在检测样品的特定图案时，电子束用于执行第二图案检测操作。 表示在第二图案检测操作期间提供给偏转线圈的电流的数据，表示样品位置的数据和表示在指定表面积中形成的图案的第二图案检测操作提供的图像信号 已存储在存储器中的数据项。 根据比较的两组数据项之间的差异，计算电子束中的任何漂移。 根据如此计算的漂移，偏转线圈被通电以使电子束分离，使得光束被施加到样品的期望部分上。

公开(公告)号：US06515296B1

公开(公告)日：2003-02-04

申请号：US09570538

申请日：2000-05-12

申请人： Fumio Komatsu ,  Motosuke Miyoshi ,  Katsuya Okumura

发明人： Fumio Komatsu ,  Motosuke Miyoshi ,  Katsuya Okumura

IPC分类号： G01N2300

CPC分类号： G01N23/225

摘要： In an operation of a pattern dimension measuring system comprising a stage, an electron gun part, electron lens systems for scanning electron beam on a sample and having a MOL mechanism thereto, a secondary electron detector for detecting secondary electrons and so forth emitted from the sample, and a host computer having a pattern dimension measuring part, the stage is moved at a constant velocity, the coordinates of the stage is measured by a laser interferometer in real time, the variation in working distance of the electron beam is measured in real time by the optical lever system from a focal length measuring part to be fed back to a stage control part and an objective lens. When a pattern serving as an object to be measured reaches a region capable of scanning, the electron beam is scanned in the best focus while moving the scanning start position of the electron beam in synchronism with the constant velocity movement of the stage, so that the SEM image thereof is acquired.

摘要翻译： 在包括阶段，电子枪部分，用于在样品上扫描电子束并具有MOL机制的电子透镜系统的图案尺寸测量系统的操作中，用于检测从样品发射的二次电子等的二次电子检测器 和具有图形尺寸测量部件的主机，以等速移动平台，通过激光干涉仪实时测量舞台的坐标，实时测量电子束的工作距离的变化 通过光学杆系统从焦距测量部分反馈到舞台控制部分和物镜。 当作为被测量物体的图案到达能够扫描的区域时，电子束以最佳聚焦扫描，同时与舞台的等速运动同步地移动电子束的扫描开始位置， 获取其SEM图像。

公开(公告)号：US5315119A

公开(公告)日：1994-05-24

申请号：US983229

申请日：1992-11-19

申请人： Fumio Komatsu ,  Katsuya Okumura ,  Motosuke Miyoshi

发明人： Fumio Komatsu ,  Katsuya Okumura ,  Motosuke Miyoshi

IPC分类号： G21K5/04 ,  H01J37/02 ,  H01J37/147 ,  H01J37/302 ,  H01L21/66

CPC分类号： H01J37/3026 ,  H01J37/026

摘要： To prevent electric charge up from being accumulated on the plane scanned by an electron beam and further to improve the S/N ratio, an electron beam irradiating apparatus comprising: position information signal outputting section for outputting position information signals, in sequence to designate positions at which an electron beam is irradiated on a plane scanned by the electron beam, so as to designate the irradiation positions at random; and irradiation controller for controlling the electron beam to irradiate the electron beam at the irradiation positions in response to the outputted position information signals. Further, to integrate an photoelectric signal over a sufficient time interval within the period of the pixel clock signal, the electric signal detecting circuit comprises a plurality of sample hold circuits and a selecting circuit for selecting and activating the sample hold circuits in sequence.

摘要翻译： 为了防止电荷积累在由电子束扫描的平面上并进一步提高S / N比，电子束照射装置包括：位置信息信号输出部分，用于输出位置信息信号，以依次指定位置信息信号 电子束照射在由电子束扫描的平面上，以便随机地指定照射位置; 以及照射控制器，用于响应于输出的位置信息信号，控制电子束在照射位置照射电子束。 此外，为了在像素时钟信号的周期内在足够的时间间隔内积分光电信号，电信号检测电路包括多个采样保持电路和用于依次选择和激活采样保持电路的选择电路。

公开(公告)号：US6114681A

公开(公告)日：2000-09-05

申请号：US90249

申请日：1998-06-04

申请人： Fumio Komatsu

发明人： Fumio Komatsu

IPC分类号： G03B13/36 ,  G02B7/04 ,  G02B7/28 ,  G02B7/36 ,  H01J37/21 ,  H01J37/26

CPC分类号： H01J37/28 ,  G02B21/241 ,  H01J2237/216 ,  H01J2237/223 ,  H01J2237/24578

摘要： An automatic focus control system comprises an electron beam lens column 1, a device control apparatus 2, and a host computer 3. In the host computer 3, an image processing section 32 and so on are provided. In case of measuring the critical dimension of the patterns in the wafer, after performing the global alignment adjustment, the power spectrum is calculated based on the SEM image of each measuring point in the wafer. After that, in case that the high-frequency component is included more than a prescribed standard value, without performing the automatic focus adjustment, the process for the pattern recognition is performed, and in case that the high-frequency component is included less than the standard value, the process for pattern recognition is performed just before the automatic focus adjustment. Therefore, it is possible to decrease the frequency (times) which performs the process for automatic focus adjustment; as a result, the throughput for measuring is improved.

摘要翻译： 自动聚焦控制系统包括电子束透镜柱1，装置控制装置2和主计算机3.在主计算机3中，设置有图像处理部32等。 在测量晶片中的图案的临界尺寸的情况下，在执行全局对准调整之后，基于晶片中每个测量点的SEM图像来计算功率谱。 之后，在高频分量多于规定标准值的情况下，不进行自动对焦调整的情况下，进行模式识别处理，在高频分量小于 在自动对焦调整之前执行模式识别的处理。 因此，可以降低进行自动对焦调整处理的频率（次数）。 结果，提高了测量的生产量。

公开(公告)号：US5887080A

公开(公告)日：1999-03-23

申请号：US379962

申请日：1995-01-27

申请人： Koji Tsubusaki ,  Hiroshi Motoki ,  Fumio Komatsu

发明人： Koji Tsubusaki ,  Hiroshi Motoki ,  Fumio Komatsu

IPC分类号： G01B11/24 ,  G03F1/84 ,  G03F1/86 ,  G06K9/00 ,  G06T1/00 ,  G06T5/00 ,  G06T5/20 ,  G06T7/60 ,  G06K9/38

CPC分类号： G06T7/0081 ,  G06K9/0014 ,  G06K2209/19 ,  G06T2207/10061 ,  G06T2207/30148

摘要： Analog image data a SEM are converted into digital data, and are processed by a spatial filtering processing, histogram processing, threshold value setting, three-valued image data processing, noise reduction and the like. Area of a pattern in the three-valued image data is calculated by a labelling and calculation processing, and a pattern is sequentially detected by comparing the area of the pattern with a reference area value. The comparison and detection of the same or similar patterns repeated in the SEM image are performed by using the area of the pattern, and are not performed by a shape of the pattern, thereby resulting a precise detection at high speed by using a microprocessor. Since it is possible to perform a pattern recognition from the area value even though the pattern does not have a characteristic, it is possible to precisely detect and recognize a pattern image in high speed.

公开(公告)号：US5555319A

公开(公告)日：1996-09-10

申请号：US237169

申请日：1994-05-03

申请人： Koji Tsubusaki ,  Fumio Komatsu

发明人： Koji Tsubusaki ,  Fumio Komatsu

IPC分类号： G01B11/24 ,  G06K9/46 ,  G06T1/00 ,  G06T7/00 ,  G06T7/40 ,  G06T7/60 ,  G06K9/00

CPC分类号： G06K9/4604

摘要： A critical dimension measuring equipment includes a filtering circuit for inputting image data from a SEM and performs spatial filtering processing of the image data, a histogram processing circuit implements histogram processing of the image data, a threshold value detection circuit obtains a threshold value based on a discriminant criteria method, a three-value conversion processing circuits implements three-value conversion of the image data based on the threshold value, a first calculation circuit obtains the area and perimeter of the bottom section of the pattern based on this data, a second calculation circuit obtains the diameters of the patterns based on this data, and a critical shape recognition circuit decide whether the pattern is circular or elliptical based on the critical diameter, calculates the diameter of the circle based on the area if the pattern is circular, and calculating the major axis and the minor axis of the ellipse based on the area and the perimeter if the pattern is elliptical.

摘要翻译： 临界尺寸测量设备包括一个滤波电路，用于从SEM输入图像数据，并执行图像数据的空间滤波处理，直方图处理电路实现图像数据的直方图处理，阈值检测电路基于 判别标准方法，三值转换处理电路基于阈值实现图像数据的三值转换，第一计算电路基于该数据获得图案的底部区域和周长，第二计算 电路基于该数据获得图案的直径，并且临界形状识别电路基于临界直径决定图案是圆形还是椭圆形，如果图案为圆形则基于面积计算圆的直径，并计算 椭圆的长轴和短轴基于面积和周长 图案是椭圆形