公开(公告)号：US4999014A

公开(公告)日：1991-03-12

申请号：US347812

申请日：1989-05-04

申请人： Nathan Gold ,  David L. Willenborg ,  Jon Opsal ,  Allan Rosencwaig

发明人： Nathan Gold ,  David L. Willenborg ,  Jon Opsal ,  Allan Rosencwaig

IPC分类号： G01B11/06 ,  G01N21/21

CPC分类号： G01N21/211

摘要： An apparatus (20) for measuring the thickness of a thin film layer (32) on substrate (28) includes a probe beam of radiation (24) focused substantially normal to the surface of the sample using a high numerical aperture lens (30). The high numerical aperture lens (30) provides a large spread of angles of incidence of the rays within the incident focused beam. A detector (50) measures the intensity across the reflected probe beam as a function of the angle of incidence with respect to the surface of the substrate (28) of various rays within the focused incident probe beam. A processor (52) functions to derive the thickness of the thin film layer based on these angular dependent intensity measurements. This result is achieved by using the angular dependent intensity measurements to solve the layer thickness using variations of the Fresnel equations. The invention is particularly suitable for measuring thin films, such as oxide layers, on silicon semiconductor samples.

公开(公告)号：US5042951A

公开(公告)日：1991-08-27

申请号：US409393

申请日：1989-09-19

申请人： Nathan Gold ,  David L. Willenborg ,  Jon Opsal ,  Allan Rosencwaig

发明人： Nathan Gold ,  David L. Willenborg ,  Jon Opsal ,  Allan Rosencwaig

IPC分类号： G01N21/21 ,  G03F7/20

CPC分类号： G03F7/70633 ,  G01N21/211

摘要： In an ellipsometric apparatus, a laser is provided for generating a probe beam. The probe beam is passed through a polarization section to give the beam a known polarization state. The probe beam is then tightly focused with a high numerical aperture lens onto the surface of the sample. The polarization state of the reflected probe beam is analyzed. In addition, the angle of incidence of one or more rays in the incident probe beam is determined based the radial position of the rays within the reflected probe beam. This approach provides enhanced spatial resolution and allows measurement over a wide spread of angles of incidence without adjusting the position of the optical components. Multiple angle of incidence measurements are greatly simplified.

摘要翻译： 在椭圆仪器中，提供用于产生探针光束的激光器。 探测光束通过偏振部分，以使光束成为已知的偏振状态。 然后将探针光束与高数值孔径透镜紧密聚焦到样品的表面上。 分析反射探测光束的偏振状态。 此外，入射探测光束中的一个或多个射线的入射角是根据反射的探测光束内的射线的径向位置来确定的。 这种方法提供了增强的空间分辨率，并且允许在大范围的入射角度上进行测量，而不调整光学部件的位置。 多个入射角测量被大大简化。

公开(公告)号：US5159412A

公开(公告)日：1992-10-27

申请号：US670040

申请日：1991-03-15

申请人： David L. Willenborg ,  Allan Rosencwaig ,  Jon Opsal

发明人： David L. Willenborg ,  Allan Rosencwaig ,  Jon Opsal

IPC分类号： G01B11/06 ,  G01M11/00 ,  G01N21/21 ,  G01N21/55 ,  G01N21/84

CPC分类号： G01N21/55 ,  G01B11/0616 ,  G01N21/211 ,  G01N21/8422 ,  G01N2201/064

摘要： An approach for increasing the sensitivity of a high resolution measurement device 50 is disclosed. The device includes a laser 52 for generating a probe beam 54 which is tightly focused onto the surface of the sample 58. A detector 66 is provided for monitoring a parameter of the reflected probe beam. In accordance with the subject invention, a spatial filter is provided for reducing the amount of light energy reaching the detector that has been reflected from areas on the surface of the sample beyond the focused spot. The spatial filter includes a relay lens 68 and a blocking member 70 located in the focal plane of the lens. The blocking member 70 includes an aperture 72 dimensioned to block light reflected from the surface of the sample beyond a predetermined distance from the center of the focused spot. In this manner, greater sensitivity to sample characteristics within the highly focused spot is achieved.

公开(公告)号：US4579463A

公开(公告)日：1986-04-01

申请号：US612075

申请日：1984-05-21

申请人： Allan Rosencwaig ,  Jon Opsal ,  Walter L. Smith ,  David L. Willenborg

发明人： Allan Rosencwaig ,  Jon Opsal ,  Walter L. Smith ,  David L. Willenborg

IPC分类号： G01J5/00 ,  G01N21/01 ,  G01N21/17 ,  G01N21/55 ,  G01N25/00 ,  G01N25/72 ,  G01N29/00 ,  G01N21/41

CPC分类号： G01N21/55 ,  G01N25/00 ,  G01N25/72

摘要： A method and apparatus is disclosed for detecting thermal waves. This system is based on the measurement of the change in reflectivity at the sample surface which is a function of the changing surface temperature. The apparatus includes a radiation probe beam that is directed on a portion of the area which is being periodically heated. A photodetector is aligned to sense the intensity changes in the reflected radiation probe beam which results from the periodic heating. These signals are processed to detect the presence of thermal waves.

摘要翻译： 公开了一种用于检测热波的方法和装置。 该系统基于样品表面的反射率变化的测量，该变化是表面温度变化的函数。 该装置包括一个辐射探针光束，该辐射探针光束被定向在正被周期性地加热的区域的一部分上。 对准光电检测器以感测由周期性加热产生的反射辐射探针光束的强度变化。 处理这些信号以检测热波的存在。

公开(公告)号：US5412473A

公开(公告)日：1995-05-02

申请号：US93178

申请日：1993-07-16

申请人： Allan Rosencwaig ,  David L. Willenborg

发明人： Allan Rosencwaig ,  David L. Willenborg

IPC分类号： G01B11/06 ,  G01J4/04 ,  G01N21/21 ,  G01N21/27 ,  H01L21/66 ,  G01B9/02

CPC分类号： G01B11/0641 ,  G01N21/211

摘要： An optical measurement device is disclosed for evaluating the parameters of a sample. The device includes a polychromatic source for generating a probe beam. The probe beam is focused on the sample surface. Individual rays within the reflected probe beam are simultaneously analyzed as a function of the position within the beam to provide information at multiple wavelengths. A filter, dispersion element and a two-dimensional photodetector array may be used so that the beam may be simultaneously analyzed at multiple angles of incidence and at multiple wavelengths. A variable image filter is also disclosed which allows a selection to be made as to the size of the area of the sample to be evaluated.

摘要翻译： 公开了一种用于评估样品参数的光学测量装置。 该装置包括用于产生探针光束的多色源。 探针光束聚焦在样品表面上。 反射探测光束内的单个光线作为光束内的位置的函数被同时分析，以提供多个波长的信息。 可以使用滤光器，色散元件和二维光电检测器阵列，使得可以以多个入射角和多个波长同时分析光束。 还公开了可变图像滤波器，其允许对要评估的样本的面积的大小进行选择。

公开(公告)号：US4795260A

公开(公告)日：1989-01-03

申请号：US50911

申请日：1987-05-15

申请人： John Schuur ,  David L. Willenborg ,  Michael W. Taylor ,  Allan Rosencwaig

发明人： John Schuur ,  David L. Willenborg ,  Michael W. Taylor ,  Allan Rosencwaig

IPC分类号： H01L21/66 ,  G01N21/17 ,  G01N21/55 ,  G01N21/95 ,  H01J37/305 ,  G01N21/00

CPC分类号： G01R31/311 ,  G01N21/17 ,  G01N2021/178 ,  G01N2021/555 ,  G01N2021/8867 ,  G01N21/9501

摘要： The subject invention relates to a method and apparatus for identifying and testing the location of areas of interest on a workpiece and specifically, unmasked areas on a semiconductor wafer. In the subject method, the surface of the wafer is scanned with a search beam of radiation. The power of the reflected search beam will be a function of the optical reflectivity of the surface of the sample. Since the optical reflectivity of the unmasked areas are different from the masked areas, the power measurement of the reflected search beam can be used to identify the location of areas to be measured. In the preferred testing procedure, an intensity modulated pump beam is used to periodically excite a region in the identified unmasked area. A probe beam is then directed within the periodically excited region and the periodic changes in the power of the reflected probe beam, induced by the pump beam, are measured to evaluate ion dopant concentrations or the effects of processing steps, such as etching, on the surface of the wafer.

公开(公告)号：US5596406A

公开(公告)日：1997-01-21

申请号：US532871

申请日：1995-08-15

申请人： Allan Rosencwaig ,  David L. Willenborg

发明人： Allan Rosencwaig ,  David L. Willenborg

IPC分类号： G01B11/06 ,  G01J4/04 ,  G01N21/21 ,  G01N21/27 ,  H01L21/66 ,  G01J4/00 ,  G01J3/28

CPC分类号： G01B11/0641 ,  G01N21/211

摘要： An optical measurement device is disclosed for evaluating the parameters of a sample. The device includes a polychromatic source for generating a probe beam. The probe beam is focused on the sample surface. Individual rays within the reflected probe beam are simultaneously analyzed as a function of the position within the beam to provide information at multiple wavelengths. A filter, dispersion element and a two-dimensional photodetector array may be used so that the beam may be simultaneously analyzed at multiple angles of incidence and at multiple wavelengths. A variable image filter is also disclosed which allows a selection to be made as to the size of the area of the sample to be evaluated.

摘要翻译： 公开了一种用于评估样品参数的光学测量装置。 该装置包括用于产生探针光束的多色源。 探针光束聚焦在样品表面上。 反射探测光束内的单个光线作为光束内的位置的函数被同时分析，以提供多个波长的信息。 可以使用滤光器，色散元件和二维光电检测器阵列，使得可以以多个入射角和多个波长同时分析光束。 还公开了可变图像滤波器，其允许对要评估的样本的面积的大小进行选择。

公开(公告)号：US06829057B2

公开(公告)日：2004-12-07

申请号：US10658176

申请日：2003-09-09

申请人： Jon Opsal ,  Allan Rosencwaig

发明人： Jon Opsal ,  Allan Rosencwaig

IPC分类号： G01B1114

CPC分类号： G01B11/024 ,  G01B11/02 ,  G01B11/14 ,  G03F7/70625

摘要： A method and apparatus are disclosed for evaluating relatively small periodic structures formed on semiconductor samples. In this approach, a light source generates a probe beam which is directed to the sample. In one preferred embodiment, an incoherent light source is used. A lens is used to focus the probe beam on the sample in a manner so that rays within the probe beam create a spread of angles of incidence. The size of the probe beam spot on the sample is larger than the spacing between the features of the periodic structure so some of the light is scattered from the structure. A detector is provided for monitoring the reflected and scattered light. The detector includes multiple detector elements arranged so that multiple output signals are generated simultaneously and correspond to multiple angles of incidence. The output signals are supplied to a processor which analyzes the signals according to a scattering model which permits evaluation of the geometry of the periodic structure. In one embodiment, the sample is scanned with respect to the probe beam and output signals are generated as a function of position of the probe beam spot.

公开(公告)号：US06774997B2

公开(公告)日：2004-08-10

申请号：US10395746

申请日：2003-03-24

申请人： Allan Rosencwaig ,  Jon Opsal

发明人： Allan Rosencwaig ,  Jon Opsal

IPC分类号： G01J400

CPC分类号： G01B11/0641

摘要： An optical measurement system is disclosed for evaluating samples with multi-layer thin film stacks. The optical measurement system includes a reference ellipsometer and one or more non-contact optical measurement devices. The reference ellipsometer is used to calibrate the other optical measurement devices. Once calibration is completed, the system can be used to analyze multi-layer thin film stacks. In particular, the reference ellipsometer provides a measurement which can be used to determine the total optical thickness of the stack. Using that information coupled with the measurements made by the other optical measurement devices, more accurate information about individual layers can be obtained.

摘要翻译： 公开了一种用于评估具有多层薄膜叠层的样品的光学测量系统。 光学测量系统包括参考椭偏仪和一个或多个非接触光学测量装置。 参考椭偏仪用于校准其他光学测量装置。 一旦校准完成，该系统可用于分析多层薄膜堆叠。 特别地，参考椭偏仪提供可用于确定叠层的总光学厚度的测量。 使用与其他光学测量装置的测量结合的信息，可以获得关于各个层的更准确的信息。

公开(公告)号：US06429943B1

公开(公告)日：2002-08-06

申请号：US09818703

申请日：2001-03-27

申请人： Jon Opsal ,  Allan Rosencwaig

发明人： Jon Opsal ,  Allan Rosencwaig

IPC分类号： C01B1114

CPC分类号： G01B11/024 ,  G01B11/02 ,  G01B11/14 ,  G03F7/70625

摘要： A method and apparatus are disclosed for evaluating relatively small periodic structures formed on semiconductor samples. In this approach, a light source generates a probe beam which is directed to the sample. In one preferred embodiment, an incoherent light source is used. A lens is used to focus the probe beam on the sample in a manner so that rays within the probe beam create a spread of angles of incidence. The size of the probe beam spot on the sample is larger than the spacing between the features of the periodic structure so some of the light is scattered from the structure. A detector is provided for monitoring the reflected and scattered light. The detector includes multiple detector elements arranged so that multiple output signals are generated simultaneously and correspond to multiple angles of incidence. The output signals are supplied to a processor which analyzes the signals according to a scattering model which permits evaluation of the geometry of the periodic structure. In one embodiment, the sample is scanned with respect to the probe beam and output signals are generated as a function of position of the probe beam spot.

摘要翻译： 公开了一种用于评估在半导体样品上形成的相对小的周期性结构的方法和装置。 在这种方法中，光源产生指向样品的探针束。 在一个优选实施例中，使用非相干光源。 使用透镜将探针束聚焦在样品上，使得探针束内的射线产生入射角的扩展。 样品上的探针光斑的尺寸大于周期结构特征之间的间距，所以一些光从结构散射。 提供了一种用于监测反射和散射光的检测器。 检测器包括多个检测器元件，其布置成使得多个输出信号同时产生并对应于多个入射角。 输出信号被提供给处理器，该处理器根据允许评估周期性结构的几何形状的散射模型分析信号。 在一个实施例中，相对于探测光束扫描样品，并且根据探针束斑的位置产生输出信号。