公开(公告)号：WO2014198516A1

公开(公告)日：2014-12-18

申请号：PCT/EP2014/060625

申请日：2014-05-23

Applicant: ASML NETHERLANDS B.V.

Inventor： CRAMER, Hugo ,  DEN BOEF, Arie, Jeffrey ,  MEGENS, Henricus ,  VAN DER SCHAAR, Maurits ,  HUANG, Te-Chih

IPC: G03F7/20

CPC classification number: G03F7/70133 ,  G03F7/70625

Abstract: A method of determining a critical-dimension-related property such as critical dimension (CD) or exposure dose. Process a wafer using a lithography apparatus in a lithographic process to produce periodic targets with different respective critical dimension biases on the wafer. Illuminate each of the targets. Measure intensity of radiation scattered by the targets. Recognize and extract each grating from the image. Determine a differential signal. Then determine the CD-related property, such as CD or exposure dose, based on the differential signal, the CD biases and knowledge that the differential signal approximates to zero at a 1:1 line-to-space ratio of such periodic targets. Use the determined critical-dimension-related property to control the lithography apparatus in the lithographic processing of subsequent wafers. In order to use just two CD biases, a calibration step may use measurements on a "golden wafer" (i.e. a reference wafer) to determine the intensity gradient for each of the CD pairs, with known CDs. Alternatively, the calibration can be based upon simulation of the sensitivity of intensity gradient to CD.

Abstract translation: 确定关键尺寸相关属性（如临界尺寸（CD））或曝光剂量的方法。 在光刻工艺中使用光刻设备处理晶片以在晶片上产生具有不同相应临界尺寸偏差的周期性靶。 照亮每个目标。 测量目标散射的辐射强度。 从图像中识别和提取每个光栅。 确定差分信号。 然后基于差分信号，CD偏差和差分信号以这种周期性目标的1：1线间比比接近零的知识来确定CD相关属性，例如CD或曝光剂量。 使用确定的临界尺寸相关属性来控制后续晶片的光刻处理中的光刻设备。 为了仅使用两个CD偏移，校准步骤可以使用“金色晶片”（即，参考晶片）上的测量来确定每个CD对与已知CD的强度梯度。 或者，校准可以基于对CD的强度梯度的灵敏度的模拟。

公开(公告)号：WO2017029110A1

公开(公告)日：2017-02-23

申请号：PCT/EP2016/068426

申请日：2016-08-02

Applicant: ASML NETHERLANDS B.V.

Inventor： JAK, Martin, Jacobus, Johan ,  SMILDE, Hendrik, Jan, Hidde ,  HUANG, Te-Chih ,  CALADO, Victor, Emanuel ,  VAN BUEL, Henricus, Wilhelmus, Maria ,  VAN HAREN, Richard, Johannes, Franciscus

IPC: G03F7/20

CPC classification number: G03F7/7065 ,  G03F7/70633

Abstract: A substrate has a plurality of overlay gratings formed thereon by a lithographic process. Each overlay grating has a known overlay bias. The values of overlay bias include for example two values in a region centered on zero and two values in a region centered on P/2, where P is the pitch of the gratings. Overlay is calculated from asymmetry measurements for the gratings using knowledge of the different overlay bias values, each of the overall asymmetry measurements being weighted by a corresponding weight factor. Each one of the weight factors represents a measure of feature asymmetry within the respective overlay grating. The calculation is used to improve subsequent performance of the measurement process, and/or the lithographic process. Some of the asymmetry measurements may additionally be weighted by a second weight factor in order to eliminate or reduce the contribution of phase asymmetry to the overlay.

Abstract translation: 衬底具有通过光刻工艺在其上形成的多个覆盖光栅。 每个覆盖光栅具有已知的叠加偏置。 叠加偏置的值包括例如在以P为中心的区域中的零点和两个值的区域中的两个值，其中P是光栅的间距。 使用不同覆盖偏差值的知识，对光栅的不对称测量计算叠加，每个整体不对称测量由相应的权重因子加权。 每个权重因子表示相应叠加光栅内的特征不对称的度量。 该计算用于提高测量过程和/或光刻过程的后续性能。 另外可以通过第二加权因子来加权一些不对称测量值，以消除或减少相位不对称对叠加层的贡献。

公开(公告)号：WO2016078862A1

公开(公告)日：2016-05-26

申请号：PCT/EP2015/074460

申请日：2015-10-22

Applicant: ASML NETHERLANDS B.V.

Inventor： LU, Yen-Wen ,  CHEN, Jay, Jianhui ,  LIU, Wei ,  MENCHTCHIKOV, Boris ,  WANG, Jen-Shiang ,  HUANG, Te-Chih

IPC: G03F7/20

CPC classification number: G01N21/8806 ,  G01B11/272 ,  G01N21/9501 ,  G01N2021/8822 ,  G03F7/70516 ,  G03F7/70633 ,  G03F7/70683

Abstract: Disclosed herein is a method to determine an overlay error between a first structure and a second structure, wherein the first structure and second structures are on different layers on a substrate and are imaged onto the substrate by a lithographic process, the method comprising: obtaining an apparent overlay error; obtaining a systematic error caused by a factor other than misalignment of the first and second structures; and determining the overlay error by removing the systematic error from the apparent overlay error. The method may alternatively comprise obtaining apparent characteristics of diffraction orders of diffraction by an overlapping portion of the first and second structures; obtaining corrected characteristics of the diffraction order; determining the overlay error from by the corrected characteristics; and adjusting characteristics of the lithographic process based on the overlay error.

Abstract translation: 本文公开了一种确定第一结构和第二结构之间的覆盖误差的方法，其中第一结构和第二结构位于衬底上的不同层上，并通过光刻工艺成像到衬底上，该方法包括：获得 明显叠加错误; 获得由除了第一和第二结构的不对准之外的因素引起的系统误差; 并通过从明显重叠错误中去除系统误差来确定覆盖误差。 该方法可以替代地包括通过第一和第二结构的重叠部分获得衍射衍射级数的明显特征; 获得衍射级的校正特性; 通过校正的特征确定覆盖误差; 并基于叠加误差调整光刻过程的特性。

公开(公告)号：WO2015124391A1

公开(公告)日：2015-08-27

申请号：PCT/EP2015/051680

申请日：2015-01-28

Applicant: ASML NETHERLANDS B.V.

Inventor： VAN DER SCHAAR, Maurits ,  DEN BOEF, Arie, Jeffrey ,  ADAM, Omer, Abubaker, Omer ,  HUANG, Te-Chih ,  ZHANG, Youping

IPC: G03F7/20

CPC classification number: G03F7/70633 ,  G01N21/47 ,  G01N21/8806 ,  G01N2201/12 ,  G03F7/70683

Abstract: There is disclosed a method of measuring a process parameter for a manufacturing process involving lithography. In a disclosed arrangement the method comprises performing first and second measurements of overlay error in a region on a substrate, and obtaining a measure of the process parameter based on the first and second measurements of overlay error. The first measurement of overlay error is designed to be more sensitive to a perturbation in the process parameter than the second measurement of overlay error by a known amount.

Abstract translation: 公开了一种测量涉及光刻的制造工艺的工艺参数的方法。 在公开的布置中，该方法包括对基板上的区域中的覆盖误差执行第一和第二测量，并且基于重叠误差的第一和第二测量值获得处理参数的度量。 重叠误差的第一次测量被设计为对过程参数中的扰动比已知量的覆盖误差的第二次测量更敏感。