Defect Scanning Detection and Analysis Method for Die

Abstract

The present invention provides a method for defect scanning detection and analysis of Dies. A scanning machine is provided, and the layout file of the wafer to be detected is imported into the scanning machine. A plurality of Dies in the wafer to be detected are integrated into a plurality of first test areas, and the scanning machine is used to detect defects in the first test areas and obtain their defect distribution images. The defect types are judged according to the defect distribution images. If the defect types are not line distribution or clustered point distribution, the scanning results are output. If there is no defect scanning deviation, the scanning results are output. If there is a defect scanning deviation, the Dies corresponding to the defect areas including line distribution or clustered point distribution are integrated into a second test area, the parameters of the scanning machine are adjusted to remove the signals causing the defect scanning deviation, and then the scanning results are output. The present invention reduces the probability of losing real defects during the screening of defect images and is not likely to cause the problem of having more signals on the defect maps produced.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and particularly to a method for defect scan detection and analysis of a Die. Background Art

[0002] In the development of semiconductor technology, defects are the main reason affecting the yield of wafers. Therefore, defect scanning plays a major role in semiconductor manufacturing. When defect scanning is required for wafers with small-sized Dies (when the size of the Die is less than 2um), with existing optical scanning machines, Dies smaller than 2um cannot be recognized. Therefore, when defect scanning is required for small Dies with existing technology, multiple Dies need to be combined into a larger Die for defect scanning (please refer to Figure 1 ).

[0003] However, there will be distortion between the combined Die and the actual Die. Since the optical scanning machine compares Dies one by one, defect scan shift is likely to occur during defect scanning after Die combination (please refer to Figure 2 、 3 ). Regarding the problem of defect scan shift, with existing technology, it is easy to lose real defects during screening and the signals on the resulting defect map are likely to be numerous (defect Scan Hot), with messy information (for example, there are actually 50, but 500 are scanned due to the influence of some distorted signals).

[0004] Therefore, for the above reasons, a method for defect scanning of small-sized Dies is needed. Summary of the Invention

[0005] In view of the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide a method for defect scan detection and analysis of a Die, which is used to solve the problems that there will be distortion between the combined Die and the actual Die in the prior art, defect scan shift is likely to occur during defect scanning after Die combination, and it is easy to lose real defects during screening for the defect scan shift problem and it is likely to cause defect scan hotspots.

[0006] To achieve the above purpose and other related purposes, the present invention provides a method for defect scan detection and analysis of a Die, including:

[0007] Step 1: Provide a scanning machine, and import the layout file of the wafer to be detected into the scanning machine;

[0008] Step 2: Integrate multiple Dies in the wafer to be detected into multiple first test areas, and use the scanning machine to perform defect detection on the first test areas and obtain their defect distribution images;

[0009] Step 3. Determine the defect type according to the defect distribution image;

[0010] If the defect type is not line distribution or clustered point distribution, output the scan result;

[0011] If the defect type is line distribution or clustered point distribution, determine whether the defect caused by line distribution or clustered point distribution is the defect scan offset caused by the scanning machine:

[0012] If there is no defect scan offset, output the scan result;

[0013] If there is a defect scan offset, integrate the dies corresponding to the defect areas with line distribution or clustered point distribution into a second test area, adjust the parameters of the scanning machine to remove the signal causing the defect scan offset, and then output the scan result.

[0014] Preferably, the scanning machine in Step 1 is an optical scanning machine.

[0015] Preferably, the layout file in Step 1 is the GDS file of the wafer to be detected.

[0016] Preferably, the size of the die in Step 2 is less than 2 microns.

[0017] Preferably, the first test area in Step 2 includes two rows of adjacent dies, with three dies in each row.

[0018] Preferably, the signals causing the defect scan offset in Step 3 include energy signals and point signals.

[0019] Preferably, in Step 3, the defect scan offset is defined by the signal value of the defect being greater than the set threshold of the scanning machine.

[0020] As described above, the method for detecting and analyzing die defects of the present invention has the following beneficial effects:

[0021] In the present invention, the layout file of the product is imported at the optical scanning machine end. When defect scanning, if it is found that there are problems with defects concentrated on a line or concentrated at fixed clustered points, the defect areas are compared with the layout file to generate a new test area, and the parameters of this test area are adjusted, thereby reducing the probability of losing real defects during the screening of defect images and not easily causing the problem of having more signals on the defect map. Description of the Drawings

[0022] Figure 1 It shows a schematic diagram of the merged die in the prior art;

[0023] Figure 2Shown as a schematic diagram of the local defect scanning offset of a wafer in the prior art;

[0024] Figure 3 Shown as a schematic diagram of the overall defect scanning offset of a wafer in the prior art;

[0025] Figure 4 Shown as the improved scanning schematic diagram of the present invention;

[0026] Figure 5 Shown as the method schematic diagram of the present invention. Specific implementation manners

[0027] The following uses specific specific examples to illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0028] Please refer to Figure 5 , the present invention provides a method for defect scanning detection and analysis of a Die, including:

[0029] Step 1, provide a scanning machine tool, and import the layout file of the wafer to be detected into the scanning machine tool;

[0030] In an optional implementation manner, the scanning machine tool in Step 1 is an optical scanning machine tool.

[0031] In an optional implementation manner, the layout file in Step 1 is the GDS file of the wafer to be detected.

[0032] Step 2, when defect scanning is required for small-sized Dies on the wafer, with the existing optical scanning machine tool, Dies smaller than 2 um cannot be recognized. Therefore, when defect scanning is required for small Dies with the existing technology, multiple Dies need to be combined into a larger Die for defect scanning. For this reason, multiple Dies in the wafer to be detected need to be integrated into multiple first test areas, and the scanning machine tool is used to detect the defects in the first test areas and obtain their defect distribution images;

[0033] In an optional implementation manner, the size of the Dies in Step 2 is less than 2 microns.

[0034] In an optional implementation manner, please refer to Figure 1 , the first test area in Step 2 includes two adjacent rows with three Dies in each row, that is, a test area with a matrix distribution of 2 * 3 Dies.

[0035] Step 3, judge the defect type according to the defect distribution image;

[0036] If the defect type is not line distribution or cluster point distribution, it indicates that there is no defect scanning deviation in the scanning result, and then the scanning result is output;

[0037] If the defect type is line distribution or cluster point distribution, then it is determined whether the defect of line distribution or cluster point distribution is caused by the defect scanning deviation of the scanning machine:

[0038] If there is no defect scanning deviation, the scanning result is output;

[0039] If there is a defect scanning deviation, the dies corresponding to the defect areas including line distribution or cluster point distribution are integrated into the second test area, that is, a new area is re-divided from the original area, and the parameters of the scanning machine are adjusted to remove the signals causing the defect scanning deviation, and then the scanning result is output.

[0040] In an alternative embodiment, the signals causing the defect scanning deviation in step three include energy signals and point signals. These messy signals will affect the scanning structure and need to be filtered out.

[0041] In an alternative embodiment, the definition of the layout offset signal is confirmed according to the scanning result of the machine. There is a signal value for each defect, which we define as the layout offset signal value. This value can be directly defined in the parameters of the scanning machine end. According to the size of the signal value at the machine end, if it exceeds this value, we define it as an offset signal. That is to say, in step three, the defect scanning deviation is defined by using the signal value of the defect being greater than the set threshold of the scanning machine.

[0042] In an alternative embodiment, please refer to Figure 4 , after filtering out the messy signals by using this method, leaving those real signals, the scanning result reduces the probability of losing real defects when screening defect images, and it is not easy to cause the problem of having more signals on the defect map obtained.

[0043] It should be noted that the illustrations provided in this embodiment only illustrate the basic concept of the present invention in a schematic manner. Therefore, only the components related to the present invention are shown in the drawings, rather than being drawn according to the number, shape, and size of the components in actual implementation. The types, quantities, and proportions of the components in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0044] In summary, the present invention imports the layout file of the product at the optical scanner stage. When defect scanning is performed, if it is found that there are problems where defects are concentrated on a line or at fixed aggregation points, the defective areas are compared with the layout file to generate a new test area, and this test area is used to adjust parameters. As a result, the probability of losing real defects during defect image screening is reduced, and it is not easy to cause the problem of having more signals on the defect map obtained. Therefore, the present invention effectively overcomes various disadvantages in the prior art and has high industrial utilization value.

[0045] The above embodiments are only illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes completed by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A method for defect scanning detection and analysis of a Die, characterized in that, it at least includes: Step 1: Provide a scanning machine tool and import the layout file of the wafer to be detected into the scanning machine tool; Step 2: Integrate multiple Dies in the wafer to be detected into multiple first test areas, and use the scanning machine tool to perform defect detection on the first test areas and obtain their defect distribution images; Step 3: Judge the defect type according to the defect distribution image; If the defect type is not line distribution or cluster point distribution, output the scanning result; If the defect type is line distribution or cluster point distribution, judge whether the defect of line distribution or cluster point distribution is the defect scanning deviation caused by the scanning of the scanning machine tool: If there is no defect scanning deviation, output the scanning result; If there is a defect scanning deviation, integrate the Dies corresponding to the defect areas of line distribution or cluster point distribution into a second test area, adjust the parameters of the scanning machine tool to remove the signal causing the defect scanning deviation, and then output the scanning result.

2. The method for defect scanning detection and analysis of a Die according to claim 1, characterized in that: The size of the Die in Step 2 is less than 2 microns.

3. The method for defect scanning detection and analysis of a Die according to claim 1, characterized in that: The first test area in Step 2 includes two rows of adjacent Dies, with three Dies in each row.

4. The method for defect scanning detection and analysis of a Die according to claim 1, characterized in that: The scanning machine tool in Step 1 is an optical scanning machine tool.

5. The method for defect scanning detection and analysis of a Die according to claim 1, characterized in that: The layout file in Step 1 is the GDS file of the wafer to be detected.

6. The method for defect scanning detection and analysis of a Die according to claim 1, characterized in that: The signals causing the defect scanning deviation in Step 3 include energy signals and point signals.

7. The method for defect scanning detection and analysis of a Die according to claim 1, characterized in that: In Step 3, the defect scanning deviation is defined by using the signal value of the defect being greater than the set threshold of the scanning machine tool.

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