阅读说明：本技术 缺陷检测方法和系统 (Defect detection method and system ) 是由 袁健思 黄莉晶 韩超 于 2019-10-12 设计创作，主要内容包括：本发明公开了一种缺陷检测方法和系统,所述缺陷检测方法包括：获取缺陷位置信息；根据缺陷位置信息得到JDV图形数据；根据JDV图形数据得到缺陷检测图像；对缺陷检测图像进行图像处理,得到二维仿真图像；将二维仿真图像与JDV图形数据进行对比,得到缺陷信息。本发明能够检测极小缺陷,提高了缺陷检测精度。(The invention discloses a defect detection method and a system, wherein the defect detection method comprises the following steps: acquiring defect position information; obtaining JDV graphic data according to the defect position information; obtaining a defect detection image according to the JDV graphic data; performing image processing on the defect detection image to obtain a two-dimensional simulation image; and comparing the two-dimensional simulation image with JDV graphic data to obtain defect information. The invention can detect the minimum defect and improve the defect detection precision.)

1. A method of defect detection, comprising:

acquiring defect position information;

obtaining JDV graphic data according to the defect position information;

obtaining a defect detection image according to the JDV graphic data;

performing image processing on the defect detection image to obtain a two-dimensional simulation image; and

and comparing the two-dimensional simulation image with the JDV graphic data to obtain defect information.

2. The method of claim 1, wherein the defect location information is obtained by scanning a wafer to be inspected with a scanner.

3. The defect detection method of claim 2, wherein the defect location information comprises location coordinate information of the defect in the entire wafer and location coordinate information of the defect in a single chip unit.

4. The defect detection method of claim 3, further comprising establishing a graphics database system in which JDV graphics data per layer on a wafer and JDV graphics data per layer for each of the die units are stored, before the step of obtaining defect location information.

5. The defect detection method of claim 4, wherein the step of deriving JDV graphics data from the defect location information comprises: and comparing the defect position information with each layer of JDV graphic data in the graphic database system to obtain JDV graphic data with preset size output by taking the position of the defect as a central point.

6. The method of claim 5, wherein a plurality of regions are divided around the defect by an imager according to the JDV graphics data, and the defect detection image is obtained by photographing the plurality of regions.

7. The defect detection method of claim 6, wherein said step of image processing said defect detection image is linearizing and digitizing said defect detection image.

8. A defect detection system, comprising: a scanning machine, a graphic database system and an image machine; the scanning machine is used for scanning the wafer to be detected to obtain the defect position information and sending the defect position information;

the graph database system is used for obtaining JDV graph data according to the received defect position information and sending the JDV graph data;

the image machine is used for obtaining a defect detection image according to the received JDV graphic data, carrying out image processing on the defect detection image to obtain a two-dimensional simulation image, and comparing the two-dimensional simulation image with the JDV graphic data to obtain defect information.

9. The defect detection system of claim 8, wherein the defect location information comprises location coordinate information of the defect in the entire wafer and location coordinate information of the defect in a single chip unit.

10. The defect detection system of claim 9, wherein the graphics database system stores therein JDV graphics data per layer on a wafer and JDV graphics data per layer for each of the chip units.

Technical Field

The invention relates to the technical field of semiconductors, in particular to a defect detection method and system.

Background

In the wafer manufacturing process, a defect detection process flow on a production line is an indispensable link, an existing detection machine is divided into a scanning (scan) machine and an image (review) machine, the existing defect scanning process is to scan a wafer to be detected through the scanning machine to obtain position coordinate information of a defect (defect), the position coordinate information is transmitted to the image machine, the image machine shoots the wafer to be detected at a position corresponding to the defect according to the obtained position coordinate information of the defect to obtain a defect image (image), the defect image is compared with the same position on a chip which is located near the defect and has the same structure as the chip where the defect is located, and the position with the strongest signal is located and then is shot to obtain a final defect detection image for defect analysis.

However, as the process size of semiconductor devices is continuously reduced, for example, as the Critical Dimension (CD) of chips is continuously reduced, a lot of very small defects (for example, the defect size is less than or equal to 100nm) may be considered as a nuisance signal (nuisance) or a noise signal and filtered due to the coordinate system deviation between a scan machine and an image (review) machine or by using the defect detection method, which may result in misjudgment of the information of the very small defects, such that the process defects cannot be found in time, and thus the wafer yield is lost.

Disclosure of Invention

The invention aims to provide a defect detection method and a defect detection system, which are used for solving the problems that the existing detection method cannot detect a tiny defect, so that a process defect cannot be found in time, and the yield of a wafer is lost.

In order to solve the problems, the invention is realized by the following technical scheme:

a method of defect detection, comprising:

acquiring defect position information;

obtaining JDV graphic data according to the defect position information;

obtaining a defect detection image according to the JDV graphic data;

performing image processing on the defect detection image to obtain a two-dimensional simulation image; and

and comparing the two-dimensional simulation image with the JDV graphic data to obtain defect information.

Optionally, the wafer to be detected is scanned by a scanner to obtain the defect position information.

Optionally, the defect location information includes location coordinate information of the defect in the whole wafer and location coordinate information of the defect in a single chip unit.

Further, before the step of obtaining the defect location information, a graph database system is established, and JDV graph data of each layer on the wafer and JDV graph data of each layer of each chip unit are stored in the graph database system.

Further, the step of obtaining JDV graphics data according to the defect location information includes: and comparing the defect position information with each layer of JDV graphic data in the graphic database system to obtain JDV graphic data with preset size output by taking the position of the defect as a central point.

Further, dividing a plurality of areas around the defect by taking the defect as a center through an image machine according to the JDV graphic data, and photographing the plurality of areas to obtain the defect detection image.

Optionally, the step of image processing the defect detection image is to perform linearization and digitization on the defect detection image.

In another aspect, the present invention further provides a defect detection system, including: a scanning machine, a graphic database system and an image machine; the scanning machine is used for scanning the wafer to be detected to obtain the defect position information and sending the defect position information;

the graph database system is used for obtaining JDV graph data according to the received defect position information and sending the JDV graph data;

the image machine is used for obtaining a defect detection image according to the received JDV graphic data, carrying out image processing on the defect detection image to obtain a two-dimensional simulation image, and comparing the two-dimensional simulation image with the JDV graphic data to obtain defect information.

Preferably, the defect location information includes location coordinate information of the defect in the entire wafer, and location coordinate information of the defect in a single chip unit.

Preferably, each layer of JDV graphics data on a wafer and each layer of JDV graphics data of each chip unit are stored in the graphics database system.

Compared with the prior art, the invention has the following advantages:

the invention provides a defect detection method, which comprises the following steps: acquiring defect position information; obtaining JDV graphic data according to the defect position information; obtaining a defect detection image according to the JDV graphic data; performing image processing on the defect detection image to obtain a two-dimensional simulation image; and comparing the two-dimensional simulation image with the JDV graphic data to obtain defect information. Therefore, the method does not carry out positioning shooting after the position with the strongest positioning signal is obtained, and the final defect detection image for defect analysis is obtained for detection by the method, but firstly obtains JDV graphic data through the defect position information; then obtaining a defect detection image according to the JDV graphic data; and then, carrying out image processing on the defect detection image to obtain a two-dimensional simulation image, and finally, comparing the two-dimensional simulation image with the JDV graphic data to obtain defect information. The invention does not have the process of mistakenly considering the tiny defect as a disturbing signal, thereby solving the problems that the tiny defect cannot be detected by the existing detection method, so that the process defect cannot be found in time, and the wafer yield is lost.

Drawings

FIG. 1 is a flowchart illustrating a defect detection method according to an embodiment of the present invention;

fig. 2 is a schematic diagram of a main process of image processing of the defect detection image according to an embodiment of the present invention.

Detailed Description

A defect detection method and system according to the present invention will be described in detail with reference to fig. 1 and 2 and the following detailed description. The advantages and features of the present invention will become more apparent from the following description. It is to be noted that the drawings are in a very simplified form and are all used in a non-precise scale for the purpose of facilitating and distinctly aiding in the description of the embodiments of the present invention. To make the objects, features and advantages of the present invention comprehensible, reference is made to the accompanying drawings. It should be understood that the structures, ratios, sizes, and the like shown in the drawings and described in the specification are only used for matching with the disclosure of the specification, so as to be understood and read by those skilled in the art, and are not used to limit the implementation conditions of the present invention, so that the present invention has no technical significance, and any structural modification, ratio relationship change or size adjustment should still fall within the scope of the present invention without affecting the efficacy and the achievable purpose of the present invention.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

As described in the background art, the conventional detection method cannot detect a very small defect, so that the process defect cannot be found in time, which causes the problem of wafer yield loss.

In order to solve the above problems, a core idea of the present invention is to provide a defect detection method, including: acquiring defect position information; obtaining JDV graphic data according to the defect position information; obtaining a defect detection image according to the JDV graphic data; performing image processing on the defect detection image to obtain a two-dimensional simulation image; and comparing the two-dimensional simulation image with the JDV graphic data to obtain defect information. Therefore, the method does not carry out positioning shooting after the position with the strongest positioning signal is obtained, and the final defect detection image for defect analysis is obtained for detection by the method, but firstly obtains JDV graphic data through the defect position information; then obtaining a defect detection image according to the JDV graphic data; and then, carrying out image processing on the defect detection image to obtain a two-dimensional simulation image, and finally, comparing the two-dimensional simulation image with the JDV graphic data to obtain defect information. The invention does not have the process of mistakenly considering the tiny defect as a disturbing signal, thereby solving the problems that the tiny defect cannot be detected by the existing detection method, so that the process defect cannot be found in time, and the wafer yield is lost.

Specifically, as shown in fig. 1, the present embodiment provides a defect detection method, including:

step S100, acquiring defect position information;

in this embodiment, the defect position information may be obtained by scanning the wafer to be detected by a scanning machine. The defect position information includes position coordinate information of the defect in the whole wafer and position coordinate information of the defect in a single chip unit.

Step S200, JDV graphic data are obtained according to the defect position information;

specifically, before step S100, a Graphic Design Stream (GDS) is established, where JDV Graphic data of each layer on the wafer and JDV Graphic data of each layer of each chip unit (die) are stored in the GDS. The JDV graph data may also be referred to as layout (JDV) graph data, where JDV is a layout used in a semiconductor process, and multiple layers of JDV graphs need to be used in a semiconductor substrate (wafer) process, and each layer of JDV graph corresponds to multiple semiconductor processing steps.

Further, the step S200 further includes: and comparing the defect position information with each layer of JDV graphic data in the graphic database system to obtain JDV graphic data with preset size output by taking the position of the defect as a central point. In this embodiment, the JDV graphic data with a size of 0.1 μm by 0.1 μm may be output, and the defect is located in the JDV graphic data center.

Step S300, obtaining a defect detection image according to the JDV graphic data;

in this embodiment, a plurality of regions are divided around the defect by using the defect as a center through an image machine according to the JDV graphic data, and the defect detection image is obtained by photographing the plurality of regions. The purpose of this step is also to obtain that the defect that is shot is located in the center of the defect detection image, so as to facilitate the subsequent further analysis of what type of defect the defect belongs to.

S400, performing image processing on the defect detection image to obtain a two-dimensional simulation image;

specifically, as shown in fig. 2, the defect detection image is specifically linearized and digitized. Fig. 2 a shows the defect detection image, fig. 2 b shows the defect detection image after it has been linearized, and fig. 2 c shows the defect detection image after it has been digitized (bright edge digitization process is performed on the edges of the graph in b), i.e. the two-dimensional simulation image or so-called image with two-dimensional lines. The defect detection image (two-dimensional simulation image) processed in the above way is most similar to the JDV pattern which is the layout used when the layer where the defect is originally formed. Therefore, the defect detection is carried out by comparing the two-dimensional simulation image with the JDV graphic data. In this embodiment, a conventional image processing method may be adopted in the specific process of performing linearization and digitization on the defect detection image, and details are not described here.

And S500, comparing the two-dimensional simulation image with the JDV graphic data to obtain defect information. Specifically, in this embodiment, a two-dimensional simulation image shown as an image c in fig. 2 may be compared with JDV graphic data, so as to obtain defect information, and through performing comparative analysis on the defect information and correct (original) JDV graphic data, more accurate defect location information may be obtained, thereby implementing accurate detection of an extremely small defect, reducing a process of repeatedly shooting for detecting the defect in the prior art, i.e., reducing detection time, saving labor, and improving accuracy of defect detection. In the present embodiment, the extremely small defects may be defects of 100nm or less.

The defect detection method is suitable for detecting the defects of the chip surface layer structure and any layer structure below the chip surface layer.

The defect detection method is also suitable for detecting whether the pattern structure in the layer with the regular pattern structure on the prepared chip is missing or not.

In summary, the embodiment first obtains JDV graphics data through the defect location information; then obtaining a defect detection image according to the JDV graphic data; and then, performing image processing on the defect detection image to obtain a two-dimensional simulation image, and finally, comparing the two-dimensional simulation image with the JDV graphic data to obtain defect information. In addition, the process of mistaking the minimum defect as the nuisance signal is not carried out in the embodiment, so that the problems that the existing detection method cannot detect the minimum defect, namely, the process defect cannot be found in time, and the wafer yield is lost can be solved.

On the other hand, based on the same inventive concept, the invention also provides a defect detection system, comprising: a scanning (scan) station, a graphic database system, and an image (review) station; the scanning machine is used for scanning the wafer to be detected to obtain the defect position information and sending the defect position information;

the graph database system is used for obtaining JDV graph data according to the received defect position information and sending the JDV graph data;

the image machine is used for obtaining a defect detection image according to the received JDV graphic data, carrying out image processing on the defect detection image to obtain a two-dimensional simulation image, and comparing the two-dimensional simulation image with the JDV graphic data to obtain defect information.

In this embodiment, the scanning platform for obtaining the defect detection image includes a critical dimension scanning electron microscope (CD-SEM) and an electron Beam inspection tool (E-Beam inspection tool); the image machine comprises: scanning electron microscope inspection camera (SEM review tool), Bright field inspection (Bright field inspection) equipment with a light source with a wavelength of 150 nm-800 nm, or dark field inspection (laser light source with dark field inspection) equipment with a laser light source.

Preferably, the defect location information includes location coordinate information of the defect in the entire wafer, and location coordinate information of the defect in a single chip unit.

Preferably, each layer of JDV graphics data on a wafer and each layer of JDV graphics data of each chip unit are stored in the graphics database system.

Therefore, the scanning machine in the defect detection system provided by the embodiment is used for scanning the wafer to be detected to obtain the defect position information and sending the defect position information; the graph database system is used for obtaining JDV graph data according to the received defect position information and sending the JDV graph data; the image machine is used for obtaining a defect detection image according to the received JDV graphic data, carrying out image processing on the defect detection image to obtain a two-dimensional simulation image, and comparing the two-dimensional simulation image with the JDV graphic data to obtain defect information. Therefore, the invention can detect the minimum defect, improve the defect detection precision, find the process defect in time and improve the wafer yield. The invention does not have the process of mistakenly considering the tiny defect as a disturbing signal, thereby solving the problems that the tiny defect cannot be detected by the existing detection method, namely the process defect cannot be found in time, and the wafer yield is lost.

In summary, the present invention provides a defect detection method, including: acquiring defect position information; obtaining JDV graphic data according to the defect position information; obtaining a defect detection image according to the JDV graphic data; performing image processing on the defect detection image to obtain a two-dimensional simulation image; and comparing the two-dimensional simulation image with the JDV graphic data to obtain defect information. Therefore, the method does not carry out positioning shooting after the position with the strongest positioning signal is obtained, and the final defect detection image for defect analysis is obtained for detection by the method, but firstly obtains JDV graphic data through the defect position information; then obtaining a defect detection image according to the JDV graphic data; and then, carrying out image processing on the defect detection image to obtain a two-dimensional simulation image, and finally, comparing the two-dimensional simulation image with the JDV graphic data to obtain defect information. The invention does not have the process of mistakenly considering the tiny defect as a disturbing signal, thereby solving the problems that the tiny defect cannot be detected by the existing detection method, namely the process defect cannot be found in time, and the wafer yield is lost.

The above description is only a preferred embodiment of the present invention, and does not limit the present invention in any way. It will be understood by those skilled in the art that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.