公开(公告)号：US06580515B1

公开(公告)日：2003-06-17

申请号：US09870350

申请日：2001-05-29

申请人： Guoguang Li ,  Rajeshwar C. Chhibber

发明人： Guoguang Li ,  Rajeshwar C. Chhibber

IPC分类号： G01B1102

CPC分类号： G01B11/303 ,  G01B11/0675

摘要： A differential interferometer is used to measure the step height between a reference region and at least one point in a measurement region using the relative phase difference as well as the measured reflectance from at least the point in the measurement region. The measured reflectance can be derived from the information provided by the differential interferometer. The measured reflectance from the reference region can also be used to provide a step height measured, where, e.g., the reference region has a changing thickness. Where the measurement region includes a composite material, e.g., copper and silicon dioxide, the step height between the reference region and the measurement region may be determined by including the area fraction or the height difference of the materials in the composite material in the final determination of the step height.

摘要翻译： 差分干涉仪用于使用相对相位差以及至少在测量区域中的点测量的反射率来测量参考区域和测量区域中的至少一个点之间的台阶高度。 测量的反射率可以从差分干涉仪提供的信息导出。 来自参考区域的测量的反射率也可以用于提供测量的台阶高度，其中例如参考区域具有变化的厚度。 当测量区域包括复合材料（例如铜和二氧化硅）时，参考区域和测量区域之间的台阶高度可以通过在最终确定中包括复合材料中的材料的面积分数或高度差来确定 的步高。

公开(公告)号：US20130050702A1

公开(公告)日：2013-02-28

申请号：US13696054

申请日：2011-06-01

申请人： Guoguang Li ,  Tao Liu ,  Edgar Genio ,  Tiezhong Ma ,  Xiaolang Yan

发明人： Guoguang Li ,  Tao Liu ,  Edgar Genio ,  Tiezhong Ma ,  Xiaolang Yan

IPC分类号： G01J3/447

CPC分类号： G01N21/211 ,  G01J3/02 ,  G01J3/0208 ,  G01J3/021 ,  G01J3/0224 ,  G01N21/21

摘要： A kind of normal incidence broadband spectroscopic polarimeter which is easy to adjust the focus, has no chromatic aberration, maintains the polarization and has simple structure. The normal incidence broadband spectroscopic polarimeter can make the probe beam normal incidence and focus on the sample surface by using at least one flat reflector element to change propagation direction of the focused beam. Moreover, the normal incidence broadband spectroscopic polarimeter contains at least one polarizer as to measure the anisotropy or non-uniform samples, such as three-dimensional profile and material optical constants of thin films consisting of the periodic structure. An optical measurement system including the normal incidence broadband spectroscopic polarimeter is also provided.

摘要翻译： 一种正常入射的宽带光谱旋光计，易于调焦，无色差，维持极化，结构简单。 正常入射的宽带光谱旋光仪可以通过使用至少一个平面反射器元件来改变聚焦光束的传播方向，使探针光束正常入射并聚焦在样品表面上。 此外，正常入射的宽带光谱旋光计包含至少一个偏振器，用于测量各向异性或非均匀样品，例如由周期性结构构成的薄膜的三维轮廓和材料光学常数。 还提供了包括正常入射宽带光谱旋光计的光学测量系统。

公开(公告)号：US07505147B1

公开(公告)日：2009-03-17

申请号：US11442208

申请日：2006-05-26

申请人： Shuqiang Chen ,  Guoguang Li

发明人： Shuqiang Chen ,  Guoguang Li

IPC分类号： G01B11/24

CPC分类号： G01B11/24 ,  G03F7/70625

摘要： Improved computation of Fourier coefficients for modeling of 2-D grating diffraction is provided. Let f(x,y) be defined in a region Ω. Typically, f(x,y) is piecewise constant (since it is a grating permittivity or inverse permittivity) and takes on various constant values in several domains in Ω. Let D be one of these domains, having a general shape. According to the invention, D is approximated as a set of trapezoids, and f(x,y) is taken to have a constant value within each of the trapezoids. Since the Fourier coefficient of a constant defined on a trapezoidal region can be analytically evaluated, an analytic approximation to the Fourier coefficient of f(x,y) on D is provided by summing the contributions from each trapezoid.

摘要翻译： 提供了用于2-D光栅衍射建模的傅里叶系数的改进计算。 令f（x，y）定义在区域Ω。 通常，f（x，y）是分段常数（因为它是光栅介电常数或反向介电常数），并且在Omega的几个域中具有各种常数值。 让D成为这些领域之一，具有一般的形状。 根据本发明，D被近似为一组梯形，并且f（x，y）被认为在每个梯形内具有恒定值。 由于可以对梯形区域中定义的常数的傅立叶系数进行分析评估，因此通过对每个梯形的贡献求和来提供D上f（x，y）的傅里叶系数的分析近似。

公开(公告)号：US07212293B1

公开(公告)日：2007-05-01

申请号：US10859252

申请日：2004-06-01

申请人： Guoguang Li ,  Shuqiang Chen ,  Phillip Walsh

发明人： Guoguang Li ,  Shuqiang Chen ,  Phillip Walsh

IPC分类号： G01B11/24

CPC分类号： G01B11/24 ,  G01N21/55

摘要： Optical characterization of lateral features of a pattern is provided. A plane-wave optical response is calculated for each feature. At least one of these plane-wave responses is calculated from an effective optical property (e.g., a waveguide modal refractive index). Such effective optical properties depend on feature geometry and on intrinsic material optical properties. The plane-wave responses for each feature are combined to generate a modeled pattern response. By fitting the modeled pattern response to a corresponding measured pattern response, estimates for pattern feature parameters are obtained. The use of an effective optical property improves model accuracy, especially for features having a size on the order of a wavelength or less, without significantly increasing computation time.

摘要翻译： 提供了图案侧向特征的光学表征。 计算每个特征的平面波光学响应。 这些平面波响应中的至少一个由有效光学特性（例如，波导模式折射率）计算。 这种有效的光学特性取决于特征几何形状和本征材料光学性质。 每个特征的平面波响应被组合以产生建模的模式响应。 通过将建模的模式响应拟合到相应的测量模式响应，获得模式特征参数的估计。 使用有效的光学特性提高了模型精确度，特别是对于具有波长或更小的量级的特征，而不显着增加计算时间。

公开(公告)号：US20140354991A1

公开(公告)日：2014-12-04

申请号：US14366637

申请日：2012-09-06

申请人： Guoguang Li ,  Tao Liu ,  Jiangyan Zhao ,  Qingyang Guo ,  Edgar Genio ,  Tiezhong Ma ,  Yang Xia

发明人： Guoguang Li ,  Tao Liu ,  Jiangyan Zhao ,  Qingyang Guo ,  Edgar Genio ,  Tiezhong Ma ,  Yang Xia

IPC分类号： G01J3/447 ,  G01B11/02

CPC分类号： G01J3/447 ,  G01B11/02 ,  G01B2210/56 ,  G01J3/0208 ,  G01J3/0224 ,  G01J3/42 ,  G01N21/21 ,  G01N2021/213 ,  G02B27/14 ,  G02B27/40

摘要： Disclosed is a normal-incidence broadband spectroscopic polarimeter containing reference beam, comprising a light source, a first reflecting unit, a first concentrating unit, a second concentrating unit, a polarizer, a first curved mirror, a first planar mirror, a second reflecting unit and a probing unit. Also disclosed is an optical measurement system, comprising the normal-incidence broadband spectroscopic polarimeter containing reference beam. The normal-incidence broadband spectroscopic polarimeter containing reference beam achieves an integral combination of the light beams after splitting, can maintain the polarization state of the light beams while increasing the light transmission efficiency, and has a low complexity.

摘要翻译： 公开了一种包含参考光束的正常入射宽带分光偏振计，包括光源，第一反射单元，第一浓缩单元，第二浓缩单元，偏振器，第一曲面镜，第一平面镜，第二反射单元 和探测单元。 还公开了一种光学测量系统，其包括含有参考光束的正常入射宽带光谱偏振计。 含有参考光束的正常入射宽带光谱旋光仪实现了分光后的光束的整体组合，可以在提高光传输效率的同时保持光束的偏振态，并且具有较低的复杂度。

公开(公告)号：US07755775B1

公开(公告)日：2010-07-13

申请号：US11542953

申请日：2006-10-03

申请人： Guoguang Li

发明人： Guoguang Li

IPC分类号： G01B11/14 ,  G01J3/02 ,  G01J3/42

CPC分类号： G01J3/02 ,  G01J3/0208 ,  G01J3/021 ,  G01J3/0229 ,  G01N21/8806 ,  G01N21/956

摘要： Apparatus and method for examining a sample with a broadband radiation while preserving a small spot and low wave front distortion. The apparatus has a broadband source for generating the broadband radiation and a first reflective optics that employ toroidal mirrors that are barrel or donut-shaped and may be placed in a crossed or parallel arrangement for producing a broadband test beam that is guided to the sample such that it is incident on it at a small spot. A sampling aperture is provided for filtering a certain center portion from the broadband test beam. A second reflective optics is provided for shaping a reflected response beam from the broadband radiation that is reflected from the spot. The response beam is delivered by second reflective optics to a detector for examination. The apparatus and method can be applied to improve wave front distortion in reflectance measurements and for performing transmittance measurements with chromatic distortion compensation. The method and apparatus further provide for efficient monitoring of the broadband test beam.

摘要翻译： 用于检测具有宽带辐射的样品的装置和方法，同时保持小斑点和低波前失真。 该装置具有用于产生宽带辐射的宽带源和采用环形反射镜的第一反射光学器件，其为圆筒形或环形形状，并且可以以交叉或平行布置放置，以产生被引导到样品的宽带测试光束 它是在一个小的地方事件。 提供采样孔径用于过滤来自宽带测试光束的某个中心部分。 提供了第二反射光学器件，用于对来自该点反射的宽带辐射的反射响应光束进行成形。 响应光束由第二反射光学器件传送到检测器进行检查。 可以应用该装置和方法来改善反射率测量中的波前失真并且可以用色差失真补偿来执行透射率测量。 该方法和装置进一步提供对宽带测试光束的有效监视。

公开(公告)号：US09176048B2

公开(公告)日：2015-11-03

申请号：US13696054

申请日：2011-06-01

申请人： Guoguang Li ,  Tao Liu ,  Edgar Genio ,  Tiezhong Ma ,  Xiaolang Yan

发明人： Guoguang Li ,  Tao Liu ,  Edgar Genio ,  Tiezhong Ma ,  Xiaolang Yan

IPC分类号： G01J4/00 ,  G01N21/21 ,  G01J3/02

CPC分类号： G01N21/211 ,  G01J3/02 ,  G01J3/0208 ,  G01J3/021 ,  G01J3/0224 ,  G01N21/21

摘要： A kind of normal incidence broadband spectroscopic polarimeter which is easy to adjust the focus, has no chromatic aberration, maintains the polarization and has simple structure. The normal incidence broadband spectroscopic polarimeter can make the probe beam normal incidence and focus on the sample surface by using at least one flat reflector element to change propagation direction of the focused beam. Moreover, the normal incidence broadband spectroscopic polarimeter contains at least one polarizer as to measure the anisotropy or non-uniform samples, such as three-dimensional profile and material optical constants of thin films consisting of the periodic structure. An optical measurement system including the normal incidence broadband spectroscopic polarimeter is also provided.

摘要翻译： 一种正常入射的宽带光谱旋光计，易于调焦，无色差，维持极化，结构简单。 正常入射的宽带光谱旋光仪可以通过使用至少一个平面反射器元件来改变聚焦光束的传播方向，使探针光束正常入射并聚焦在样品表面上。 此外，正常入射的宽带光谱旋光计包含至少一个偏振器，用于测量各向异性或非均匀样品，例如由周期性结构构成的薄膜的三维轮廓和材料光学常数。 还提供了包括正常入射宽带光谱旋光计的光学测量系统。

公开(公告)号：US08767209B2

公开(公告)日：2014-07-01

申请号：US13701698

申请日：2011-05-30

申请人： Guoguang Li ,  Tao Liu ,  Edgar Genio ,  Tiezhong Ma ,  Yan Xiaolang

发明人： Guoguang Li ,  Tao Liu ,  Edgar Genio ,  Tiezhong Ma ,  Yan Xiaolang

IPC分类号： G01J4/00 ,  G01N21/21

CPC分类号： G01N21/211 ,  G01J3/02 ,  G01J3/0208 ,  G01J3/021 ,  G01J3/0224 ,  G01N21/21

摘要： An oblique incidence broadband spectroscopic polarimeter which is easy to adjust the focus, achromatic, maintains the polarization and has simple structure is provided. It comprise at least one polarizer (P, A), at least one curved reflector element (OAP1, OAP2, OAP3, OAP4) and at least two flat reflector elements (M1, M2). By utilizing the flat reflector element, the oblique incidence broadband spectroscopic polarimeter can change the propagate direction of beam, and compensate the polarization changes caused by the reflective focusing unit, make the polarization of beam passed the polarizer unchanged when obliquely incident and focus on the sample surface. The oblique incidence broadband spectroscopic polarimeter can accurately measure the optical constants of sample material, film thickness, and/or the critical dimension (CD) properties or three-dimensional profile for analyze the periodic structure of the sample. An optical measurement system including the oblique incidence broadband spectroscopic polarimeter is also provided.

摘要翻译： 提供了一种易于调整焦点，消色差，保持极化并具有简单结构的倾斜入射宽带光谱偏振计。 它包括至少一个偏振器（P，A），至少一个弯曲反射器元件（OAP1，OAP2，OAP3，OAP4）和至少两个平面反射器元件（M1，M2）。 通过利用平面反射元件，倾斜入射宽带光谱旋光计可以改变光束的传播方向，并补偿由反射聚焦单元引起的偏振变化，使得当倾斜入射时光束的偏振通过偏振器不变，并聚焦在样品上 表面。 倾斜入射宽带光谱旋光计可以精确测量样品材料的光学常数，膜厚度和/或临界尺寸（CD）性质或三维轮廓，以分析样品的周期性结构。 还提供了包括斜入射宽带光谱偏振计的光学测量系统。

公开(公告)号：US07289214B1

公开(公告)日：2007-10-30

申请号：US10997210

申请日：2004-11-23

申请人： Guoguang Li ,  Shuqiang Chen ,  Abdul Rahim Forouhi

发明人： Guoguang Li ,  Shuqiang Chen ,  Abdul Rahim Forouhi

IPC分类号： G01G11/00

CPC分类号： G03F9/7076 ,  G03F7/70633

摘要： A system and method for optical offset measurement is provided. An offset between two grating layers in a compound grating is measured by illuminating the gratings with light having a plane of incidence that is neither parallel with nor perpendicular to the grating lines. This non-symmetrical optical illumination allows determination of the sign and magnitude of the offset. Two measurements are performed at azimuthal angles separated by 180°, and a difference of these measurements is calculated. Measurement of this difference allows determination of the offset (e.g., with a calibration curve). Alternatively, two compound gratings having a predetermined non-zero offset difference can be employed. This arrangement permits determination of the offsets without the need for a calibration curve (or for additional compound gratings), based on a linear approximation.

摘要翻译： 提供了一种用于光学偏移测量的系统和方法。 复合光栅中的两个光栅层之间的偏移通过用不具有平行于或不垂直于光栅线的入射平面的光照射光栅来测量。 这种非对称光学照明允许确定偏移的符号和幅度。 在以180°分开的方位角进行两次测量，并计算这些测量值的差。 该差异的测量允许确定偏移（例如，利用校准曲线）。 或者，可以采用具有预定非零偏移差的两个复合光栅。 这种布置允许基于线性近似来确定偏移而不需要校准曲线（或用于附加复合光栅）。

公开(公告)号：US07253909B1

公开(公告)日：2007-08-07

申请号：US11028894

申请日：2005-01-03

申请人： Guoguang Li ,  Phillip Walsh ,  Shuqiang Chen ,  Abdul Rahim Forouhi

发明人： Guoguang Li ,  Phillip Walsh ,  Shuqiang Chen ,  Abdul Rahim Forouhi

IPC分类号： G01B11/00

CPC分类号： G01B11/0625 ,  G01N21/4788 ,  G01N21/59 ,  G01N21/956 ,  G01N2021/4735

摘要： An apparatus and method for determining a physical parameter of features on a substrate by illuminating the substrate with an incident light covering an incident wavelength range Δλ, e.g., from 190 nm to 1000 nm, where the substrate is at least semi-transparent. A response light received from the substrate and the feature is measured to obtain a response spectrum of the response light. Further, a complex-valued response due to the feature and the substrate is computed and both the response spectrum and the complex-valued response are used in determining the physical parameter. A direct approximate phase measurement is provided when the response light is transmitted light.

摘要翻译： 一种用于通过用覆盖入射波长范围（例如190nm至1000nm）的入射光照射衬底来确定衬底上特征的物理参数的装置和方法，其中衬底至少是半透明的。 测量从衬底接收的响应光和特征以获得响应光的响应光谱。 此外，计算由特征和衬底引起的复值响应，并且在确定物理参数中使用响应谱和复值响应。 当响应光透射光时，提供直接近似相位测量。