公开(公告)号：US06931361B2

公开(公告)日：2005-08-16

申请号：US10877397

申请日：2004-06-25

申请人： Jon Opsal ,  Hanyou Chu

发明人： Jon Opsal ,  Hanyou Chu

IPC分类号： G01B11/02 ,  G01B11/24 ,  G01N21/21 ,  G01N21/27 ,  G03F7/20 ,  G06F17/00 ,  H01L21/027 ,  H01L21/66

CPC分类号： G03F7/70616 ,  G01B11/24 ,  G01N21/211 ,  G03F7/705 ,  G03F7/70625

摘要： A system for characterizing periodic structures formed on a sample on a real time basis is disclosed. A spectroscopic measurement module generates output signals as a function of wavelength. The output signals are supplied to a processor for evaluation, which creates an initial theoretical model having a rectangular structure. The processor calculates the theoretical optical response of that sample, which is compared to normalized measured values at each of a plurality of wavelengths. The model configuration is then modified to be closer to the actual measured structure. The processor recalculates the optical response and compares the result to the normalized data. This process is repeated in an iterative manner until a best fit rectangular shape is obtained. Thereafter, the complexity of the model is iteratively increased, and model is iteratively fit to the data until a best fit model is obtained which is similar to the periodic structure.

摘要翻译： 公开了一种用于表征实时地在样品上形成的周期性结构的系统。 光谱测量模块产生作为波长的函数的输出信号。 将输出信号提供给用于评估的处理器，这产生具有矩形结构的初始理论模型。 处理器计算该样本的理论光学响应，其与多个波长中的每个波长处的归一化测量值进行比较。 然后将模型配置修改为更接近实际测量结构。 处理器重新计算光学响应，并将结果与​​归一化数据进行比较。 以迭代的方式重复该过程，直到获得最佳拟合的矩形形状。 此后，模型的复杂性被迭代地增加，并且模型迭代地适合数据，直到获得类似于周期性结构的最佳拟合模型。

公开(公告)号：US06919964B2

公开(公告)日：2005-07-19

申请号：US10345814

申请日：2003-01-16

申请人： Hanyou Chu

发明人： Hanyou Chu

IPC分类号： G03F7/20 ,  G01B11/00

CPC分类号： G03F7/70625

摘要： A method for modeling diffraction includes constructing a theoretical model of the subject. A numerical method is then used to predict the output field that is created when an incident field is diffracted by the subject. The numerical method begins by computing the output field at the upper boundary of the substrate and then iterates upward through each of the subject's layers. Structurally simple layers are evaluated directly. More complex layers are discretized into slices. A finite difference scheme is performed for these layers using a recursive expansion of the field-current ratio that starts (or has a base case) at the lowermost slice. The combined evaluation, through all layers, creates a scattering matrix that is evaluated to determine the output field for the subject.

公开(公告)号：US06898596B2

公开(公告)日：2005-05-24

申请号：US10145848

申请日：2002-05-14

申请人： David M. Aikens ,  Youxian Wen ,  Walter Lee Smith

发明人： David M. Aikens ,  Youxian Wen ,  Walter Lee Smith

IPC分类号： G01N21/47 ,  G01N21/95 ,  G01N21/956 ,  G06F17/30

CPC分类号： G01N21/47 ,  G01N21/9501 ,  G01N21/956 ,  Y10S707/99936 ,  Y10S707/99943

摘要： An optical metrology includes a library, a metrology tool and a library evolution tool. The library is generated to include a series of predicted measurements. Each predicted measurement is intended to match the measurements that a metrology device would record when analyzing a corresponding physical structure. The metrology tool compares its empirical measurements to the predicted measurements in the library. If a match is found, the metrology tool extracts a description of the corresponding physical structure from the library. The library evolution tool operates to improve the efficiency of the library. To make these improvements, the library evolution tool statistically analyzes the usage pattern of the library. Based on this analysis, the library evolution tool increases the resolution of commonly used portions of the library. The library evolution tool may also optionally reduce the resolution of less used portions of the library.

摘要翻译： 光学计量学包括图书馆，计量工具和图书馆进化工具。 生成库以包括一系列预测的测量。 每个预测的测量旨在与测量设备在分析相应的物理结构时记录的测量值相匹配。 计量工具将其经验测量与库中的预测测量进行比较。 如果找到匹配项，则计量工具从库中提取对应物理结构的描述。 图书馆进化工具可以提高图书馆的效率。 为了进行这些改进，图书馆进化工具统计分析图书馆的使用模式。 基于此分析，图书馆进化工具增加了图书馆常用部分的分辨率。 图书馆进化工具还可以选择性地降低图书馆较少使用部分的分辨率。

公开(公告)号：US5973787A

公开(公告)日：1999-10-26

申请号：US76673

申请日：1998-05-12

申请人： David E. Aspnes ,  Jon Opsal

发明人： David E. Aspnes ,  Jon Opsal

IPC分类号： G01N21/21 ,  G01B11/06 ,  G01J3/02 ,  G01J3/447 ,  G01J4/00 ,  G01J4/04 ,  G02F1/01

CPC分类号： G01J3/02 ,  G01J3/0229 ,  G01J3/0232 ,  G01N21/211 ,  G01N2021/213

摘要： An ellipsometer, and a method of ellipsometry, for analyzing a sample using a broad range of wavelengths, includes a light source for generating a beam of polychromatic light having a range of wavelengths of light for interacting with the sample. A polarizer polarizes the light beam before the light beam interacts with the sample. A rotating compensator induces phase retardations of a polarization state of the light beam wherein the range of wavelengths and the compensator are selected such that at least a first phase retardation value is induced that is within a primary range of effective retardations of substantially 135.degree. to 225.degree., and at least a second phase retardation value is induced that is outside of the primary range. An analyzer interacts with the light beam after the light beam interacts with the sample. A detector measures the intensity of light after interacting with the analyzer as a function of compensator angle and of wavelength, preferably at all wavelengths simultaneously. A processor determines the polarization state of the beam as it impinges the analyzer from the light intensities measured by the detector.

公开(公告)号：US5798837A

公开(公告)日：1998-08-25

申请号：US890697

申请日：1997-07-11

申请人： David E. Aspnes ,  Jon Opsal ,  Jeffrey T. Fanton

发明人： David E. Aspnes ,  Jon Opsal ,  Jeffrey T. Fanton

IPC分类号： G01B11/06 ,  G01J4/00 ,  G01N21/21

CPC分类号： G01B11/0641 ,  G01J4/00 ,  G01N21/211

摘要： An optical measurement system for evaluating a reference sample that has at least a partially known composition. The optical measurement system includes a reference ellipsometer and at least one non-contact optical measurement device. The reference ellipsometer includes a light generator, an analyzer and a detector. The light generator generates a beam of quasi-monochromatic light having a known wavelength and a known polarization for interacting with the reference sample. The beam is directed at a non-normal angle of incidence relative to the reference sample to interact with the reference sample. The analyzer creates interference between the S and P polarized components in the light beam after the light beam has interacted with reference sample. The detector measures the intensity of the light beam after it has passed through the analyzer. A processor determines the polarization state of the light beam entering the analyzer from the intensity measured by the detector, and determines an optical property of the reference sample based upon the determined polarization state, the known wavelength of light from the light generator and the composition of the reference sample. The processor also operates the optical measurement device to measure an optical parameter of the reference sample. The processor calibrates the optical measurement device by comparing the measured optical parameter from the optical measurement device to the determined optical property from the reference ellipsometer.

公开(公告)号：US5596411A

公开(公告)日：1997-01-21

申请号：US614522

申请日：1996-03-18

申请人： Jeffrey T. Fanton ,  Jon Opsal

发明人： Jeffrey T. Fanton ,  Jon Opsal

IPC分类号： G01N21/21 ,  G01N21/27 ,  G01J4/00

CPC分类号： G01N21/211

摘要： An optical inspection apparatus is disclosed for generating an ellipsometric output signal at a plurality of wavelengths, each signal being representative of an integration of measurements at a plurality of angles of incidence. A polarized, broad band light beam is focused through a lens onto a sample in a manner to create a spread of angles of incidence. The reflected beam is passed through a quarter-wave plate and a polarizer which creates interference effects between the two polarizations states in the beam. The beam is then passed through a filter which transmits two opposed radial quadrants of the beam and blocks light striking the remaining two quadrants. The beam is then focused and angularly dispersed as function of wavelength. Each element of a one dimensional photodetector array generates an output signal associated with a specific wavelength and represents an integration of the phase-sensitive ellipsometric parameter (.delta.) at a plurality of angles of incidence. A second, independent measurement is taken in order to isolate the signal of interest. In one embodiment, the azimuthal angle of the filter is rotated by ninety degrees. The output signals from the second measurement are subtracted from the corresponding output signals from the first measurement to obtain the phase-sensitive ellipsometric information at a plurality of wavelengths. The ellipsometric information is used to analyze the sample.

摘要翻译： 公开了一种用于在多个波长处产生椭偏输出信号的光学检查装置，每个信号代表多个入射角的测量的积分。 极化的宽带光束以透镜角度聚焦到样品上，以产生入射角的扩展。 反射光束通过四分之一波片和偏振器，在光束中的两个极化状态之间产生干涉效应。 然后将光束通过过滤器，该过滤器透射两个相对的辐射象限的光束并阻挡发射到剩余的两个象限的光。 然后将光束聚焦并作为波长的函数成角度地分散。 一维光电检测器阵列的每个元件产生与特定波长相关联的输出信号，并且表示多个入射角的相敏椭偏参数（delta）的积分。 进行第二次独立测量以便隔离感兴趣的信号。 在一个实施例中，过滤器的方位角旋转九十度。 从第一测量的相应输出信号中减去来自第二测量的输出信号，以获得多个波长的相敏椭偏信息。 椭偏信息用于分析样品。

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：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：US4679946A

公开(公告)日：1987-07-14

申请号：US612077

申请日：1984-05-21

申请人： Allan Rosencwaig ,  Jon Opsal

发明人： Allan Rosencwaig ,  Jon Opsal

IPC分类号： G01N25/00 ,  G01B11/06 ,  G01N21/17 ,  G01N21/21 ,  G01N21/55 ,  G01N25/18 ,  G01N25/72 ,  G01N29/00 ,  G01N21/41

CPC分类号： G01N21/1702 ,  G01B11/0658 ,  G01N21/55 ,  G01N25/72 ,  G01N21/21 ,  G01N2201/1087

摘要： The subject invention discloses a method and apparatus for evaluating both the thickness and compositional variables in a layered or thin film sample. Two independent detection systems are provided for measuring thermal waves generated in a sample by a periodic, localized heating. One detection system is of the type that generates output signals that are primarily a function of the surface temperature of the sample. The other detection system generates signals that are primarily a function of the integral of the temperature beneath the sample surface. The two independent thermal wave measurements permit analysis of both thickness and compositional variables. An apparatus is disclosed wherein both detection systems can be implemented efficiently within one apparatus.

摘要翻译： 本发明公开了一种用于评估层状或薄膜样品中的厚度和组成变量的方法和装置。 提供了两个独立的检测系统，用于通过周期性的局部加热来测量样品中产生的热波。 一种检测系统是产生主要是样品表面温度的函数的输出信号的类型。 另一个检测系统产生主要是样品表面下方温度积分函数的信号。 两个独立的热波测量允许分析厚度和组成变量。 公开了一种在一个装置内可以有效地实现两个检测系统的装置。

公开(公告)号：US4636088A

公开(公告)日：1987-01-13

申请号：US612076

申请日：1984-05-21

申请人： Allan Rosencwaig ,  Walter L. Smith

发明人： Allan Rosencwaig ,  Walter L. Smith

IPC分类号： G01N21/00 ,  G01N21/17 ,  G01N21/55 ,  G01N21/41 ,  G01N25/00

CPC分类号： G01N21/171

摘要： An apparatus and method is disclosed for evaluating surface conditions on a sample. The system is particularly suited for detecting thin residues encountered in semiconductor lithographic and etching processes. The system is also capable of measuring ion implanted dopant concentrations prior to annealing. The apparatus includes an intensity modulated laser beam which is focused on the surface of the sample to generate periodic heating. A second light beam is focused onto the periodically heated area of the sample in a manner such that it is reflected to a detector. The intensity changes in the probe beam, resulting from the temperature induced changes of reflectivity at the surface of the sample, are measured and evaluated to determine the absence or presence of residues, or to measure the concentrations of ion implanted dopants.

摘要翻译： 公开了一种用于评估样品上的表面状况的装置和方法。 该系统特别适用于检测半导体光刻和蚀刻工艺中遇到的薄残留物。 该系统还能够在退火之前测量离子注入的掺杂剂浓度。 该装置包括强度调制的激光束，其聚焦在样品的表面上以产生周期性加热。 第二光束以使得其被反射到检测器的方式聚焦在样品的周期性加热区域上。 测量和评估由温度引起的样品表面反射率变化导致的探针光束强度变化，以评估残留物的不存在或存在，或测量离子注入掺杂剂的浓度。