A wafer continuous result analysis method

Abstract

The present disclosure discloses a wafer continuous result analysis method, comprising the following steps: S100: obtaining a two-dimensional array of wafer test results, traversing the array row by row, selecting and recording continuous 0 elements in each row and recording them as a group; S200: recording the coordinates of each group in the two-dimensional array, and numbering all groups, and obtaining a group list after completing the array row by row traversal; S300: traversing the group list row by row according to the vertical coordinate; S400: re-stating the group list after row by row traversal to obtain the final continuous block. The present disclosure can reduce the time consumption of analysis, improve the efficiency of wafer continuous result analysis, and prevent the system from crashing due to resource exhaustion caused by the increase of data volume.

Description

Technical Field

[0001] The present invention belongs to the field of wafer testing technology, and in particular relates to a wafer continuous result analysis method. Background Art

[0002] Currently, many CP wafer tests simply analyze the X / Y axis continuity or 4 / 8 connected domains through recursion, but cannot combine these four to obtain continuous results.

[0003] For some products with strict requirements, when continuous blocks appear in a patch-like manner and mainly present Fail defects, considering the risk of good product Die outside the block defects, the infected peripheral good product PassDie needs to be changed to a specified bad FailDie; to obtain continuous results, the idea of ​​recursion is needed, and the 4 / 8 connected domain around the bad FailDie is analyzed continuously with the latest fail result as the origin. However, recursion requires continuous space opening and releasing, which is inefficient and time-consuming. At the same time, when the continuous block area in the test result is too large, the recursion will continue to push the stack, which will cause the memory space to be exhausted, causing memory overflow, and thus causing the system to crash. Summary of the invention

[0004] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a wafer continuous result analysis method, which can improve the analysis speed and reduce memory space loss, thereby preventing the system from crashing due to insufficient resources.

[0005] To achieve the above objectives, the present disclosure provides the following technical solutions:

[0006] A wafer continuous result analysis method comprises the following steps:

[0007] S100: Obtain a two-dimensional array of wafer test results, traverse the array row by row, select and record consecutive 0 elements in each row and record them as a group;

[0008] S200: Record the coordinates of each group in the two-dimensional array, number all groups, and obtain a group list after traversing the array row by row;

[0009] S300: traverse the group list row by row according to the vertical coordinate;

[0010] S400: re-counting the group list after traversing row by row to obtain a final continuous block.

[0011] Preferably, in step S100, in each row of the array, the number of 0 elements is greater than or equal to 1, and each is recorded as a group.

[0012] Preferably, in step S300, a group with a vertical coordinate of 1 is selected to start traversing the group list row by row.

[0013] Preferably, in step S300, in the process of traversing the group list row by row according to the vertical coordinate, the numbers corresponding to the groups whose coordinates are located on a straight line in two adjacent rows are recorded as an equivalent pair.

[0014] Preferably, the groups whose coordinates are on a straight line in two adjacent rows means that the line connecting the coordinates of the groups in two adjacent rows is any one of a parallel line, a vertical line and an oblique line.

[0015] Preferably, in step S400, a list whose coordinate quantity meets the requirement in the re-counted group list is selected as the final continuous block.

[0016] In addition, the present invention also discloses a wafer continuous result analysis device, comprising:

[0017] The group marking unit is used to obtain the two-dimensional array of wafer test results, traverse the array row by row, select and record the continuous 0 elements in each row and record them as a group;

[0018] The list acquisition unit is used to record the coordinates of each group in the two-dimensional array and number all groups. After traversing the array row by row, the group list is obtained.

[0019] List traversal unit, used to traverse the group list row by row according to the vertical coordinate;

[0020] The continuous block obtaining unit is used to re-count the group list after traversing row by row to obtain the final continuous block.

[0021] Preferably, in the group marking unit, in each row of the array, the number of 0 elements is greater than or equal to 1, and each is recorded as a group.

[0022] Preferably, in the list traversal unit, a group with a vertical coordinate of 1 is selected to start traversing the group list row by row.

[0023] Preferably, in the list traversal unit, in the process of traversing the group list row by row according to the vertical coordinate, the numbers corresponding to the groups whose coordinates are located on a straight line in two adjacent rows are recorded as an equivalent pair.

[0024] Preferably, in the continuous block obtaining unit, a list whose coordinate quantity meets the requirement in the re-counted group list is selected as the final continuous block.

[0025] Compared with the prior art, the present invention has the following beneficial effects: the present invention can reduce the time consumption of analysis, improve the efficiency of wafer continuous result analysis, and prevent the system from crashing due to resource exhaustion caused by the increase of data volume. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a flow chart of a wafer continuous result analysis method provided by an embodiment of the present disclosure;

[0027] Figure 2 It is a schematic diagram of the time consumption comparison between the method disclosed in the present invention and the recursive method;

[0028] FIG3( a ) is a schematic diagram of the analysis results of a 50*50 array using the method disclosed in the present invention;

[0029] FIG3( b ) is a schematic diagram of the analysis results of a 50*50 array using a recursive method;

[0030] FIG3( c ) is a schematic diagram showing the comparison of the analysis results of the method disclosed in the present invention and the recursive method for a 50*50 array;

[0031] FIG4( a ) is a schematic diagram of the analysis results of a 100*100 array using the method disclosed in the present invention;

[0032] FIG4( b ) is a schematic diagram of the analysis results of a 100*100 array using a recursive method;

[0033] FIG4( c ) is a schematic diagram showing the comparison of the analysis results of the method of the present disclosure and the recursive method for a 100*100 array;

[0034] FIG5( a ) is a schematic diagram of the analysis results of a 120*120 array using the method disclosed in the present invention;

[0035] FIG5( b ) is a schematic diagram of the analysis result of a 120*120 array using a recursive method;

[0036] FIG5( c ) is a schematic diagram showing the comparison of the analysis results of the method disclosed in the present invention and the recursive method for a 120*120 array. DETAILED DESCRIPTION

[0037] The following will refer to the attached Figure 1 to Figure 5(c) Specific embodiments of the present disclosure are described in detail. Although specific embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0038] It should be noted that certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that technicians may use different nouns to refer to the same component. This specification and claims do not use the difference in nouns as a way to distinguish components, but use the difference in the functions of the components as the criterion for distinction. As mentioned throughout the specification and claims, "including" or "comprising" is an open term, so it should be interpreted as "including but not limited to". The subsequent description of the specification is a preferred embodiment of the present disclosure, but the description is based on the general principles of the specification and is not used to limit the scope of the present disclosure. The scope of protection of the present disclosure shall be determined by the attached claims.

[0039] To facilitate understanding of the embodiments of the present disclosure, further explanation will be given below using specific embodiments as examples in conjunction with the accompanying drawings, and each of the accompanying drawings does not constitute a limitation on the embodiments of the present disclosure.

[0040] In one embodiment, if Figure 1 As shown, the present disclosure provides a wafer continuous result analysis method, comprising the following steps:

[0041] S100: Obtain a two-dimensional array of wafer test results, traverse the array row by row, select and record continuous elements in each row according to the screening condition and record them as a group;

[0042] S200: Record the coordinates of each group in the two-dimensional array, number all groups, and obtain a group list after traversing the array row by row;

[0043] S300: traverse the group list row by row according to the vertical coordinate;

[0044] S400: re-counting the group list after traversing row by row to obtain a final continuous block.

[0045] Below, the present disclosure provides an illustrative description of the method described in the above embodiment in combination with specific data.

[0046] Exemplarily, obtain the 5*5 two-dimensional array arr of wafer test results as shown below:

[0047] [0, 1, 1, 0, 0]

[0048] [1, 0, 1, 0, 1]

[0049] [1, 1, 1, 0, 0]

[0050] [1, 1, 1, 1, 0]

[0051] [0, 1, 0, 1, 1]

[0052] In this array, 0 represents FAIL and 1 represents PASS. This embodiment needs to analyze from the above array to find out the FAIL group with more than 3 consecutive FAILs on the 8-connected domain (that is, the other 8 coordinates within the 3*3 range centered on a single element), that is, a continuous block with more than 3 consecutive 0s.

[0053] Exemplarily, the method of the present invention is implemented according to the following specific steps:

[0054] 1. Traverse the array arr row by row, determine whether it is 0 according to the filtering condition, find the consecutive 0s in each row of the array arr, record them as a group, save the groups of all rows in a list groupList, and number all the groups.

[0055] For example:

[0056] There are two groups in the first row [0, 1, 1, 0, 0] (the number of consecutive 0s is greater than or equal to 1, which can be regarded as a group. The first element in the row is 0 and the second element is 1, then it is considered that there is one consecutive 0, recorded as the first group; the third element is 1, and the fourth and fifth elements are two consecutive 0s, recorded as the second group), among which, the list of the first group groupList[0] (0 represents the first consecutive 0) contains the coordinates (0, 0) (that is, the horizontal coordinate and vertical coordinate of the first consecutive 0 are both 0), and is numbered 1; groupList[1] (1 represents the second consecutive 0) contains the coordinates (3, 0), (4, 0) (that is, the horizontal coordinate of the first 0 in the second consecutive 0 is 3, and the vertical coordinate is 0; the horizontal coordinate of the second 0 in the second consecutive 0 is 4, and the vertical coordinate is 0), and is numbered 2;

[0057] Similarly, there are two groups in the second row [1, 0, 1, 0, 1]. groupList[2] (2 means the third consecutive 0) contains coordinates (1, 1) and is numbered 3; groupList[3] (3 means the fourth consecutive 0) contains coordinates (3, 1) and is numbered 4.

[0058] There is a group in the third row [1, 1, 1, 0, 0]. groupList[4] contains coordinates (3, 2), (4, 2) and is numbered 5.

[0059] There is a group in the fourth row [1, 1, 1, 1, 0]. groupList[5] contains the coordinates (4, 3) and is numbered 6.

[0060] There are two groups in the fifth row [0, 1, 0, 1, 1]. groupList[6] contains coordinates (0, 4) and is numbered 7; groupList[7] contains coordinates (2, 4) and is numbered 8.

[0061] The list of groups numbered 1 to 8 in the first to fifth rows is shown in Table 1:

[0062] Table 1

[0063] Line Number serial number First row Number 1 - (0, 0), number 2 - (3, 0), (4, 0) Second row No. 3-(1, 1), No. 4-(3, 1) Third row No. 5-(3, 2), (4, 2) Fourth row No. 6-(4,3) Fifth row No. 7-(0, 4), No. 8-(2, 4)

[0064] 2. Starting from the second row in Table 1 (i.e., the vertical coordinate is 1), traverse the groups in each row and compare whether the line connecting its coordinates with the coordinates of the group in the previous row is on a straight line (a straight line includes any of a parallel line, a vertical line, and a diagonal line). If they are on a straight line, they are called adjacent, and the numbers of the groups on a straight line in the adjacent rows are changed to be the same.

[0065] For example:

[0066] The coordinates (1, 1) of the group numbered 3 in the second row and the coordinates (0, 0) of the group numbered 1 in the first row are on an oblique line, so 3 and 1 are recorded as an equivalent pair {1, 3}; the coordinates (3, 1) of the group numbered 4 in the second row and the coordinates (3, 0) of the group numbered 2 in the first row are on a vertical line, so 4 and 2 are recorded as an equivalent pair {2, 4}.

[0067] The coordinates (3, 2) of the group numbered 5 in the third row and the coordinates (3, 1) of the group numbered 4 in the second row are on a vertical line, so the numbers 5 and 4 are recorded as an equivalent pair {4, 5};

[0068] The coordinates (4, 3) of the group numbered 6 in the fourth row and the coordinates (4, 2) of the group numbered 5 in the third row are on a vertical line, so the numbers 6 and 5 are recorded as an equivalent pair {5, 6};

[0069] The coordinates (0, 4) of the group numbered 7 in the fifth row and the coordinates (2, 4) of the group numbered 8 and the coordinates (4, 3) of the group numbered 6 in the fourth row do not belong to any of the cases of parallel lines, vertical lines and oblique lines, so numbers 7, 8 and number 6 are not recorded as an equivalent pair.

[0070] Arrange all equivalent pairs and count the equivalent numbers into a large group. Finally, there are four groups of equivalent relations: {1, 3}, {2, 4, 5, 6}, {7}, and {8}. Record the coordinates in the groups with equivalent numbers into the same list. The sorted list is as follows:

[0071] GroupList[0] corresponds to the group numbered {1, 3}, which contains (0, 0) and (1, 1), a total of 2 coordinates;

[0072] GroupList[1] corresponds to the group numbered {2, 4, 5, 6}, which contains (3, 0), (4, 0), (3, 1), (3, 2), (4, 2), (4, 3), a total of 6 coordinates;

[0073] GroupList[2] corresponds to group number {7}, which contains (0, 4), a total of 1 coordinate;

[0074] GroupList[3] corresponds to group number {8}, which contains (2, 4), a total of 1 coordinate.

[0075] 3. Count the number of coordinates in the final GroupList[0]-GroupList[3]. In this embodiment, only one list GroupList[1] meets the conditions of this example, and the number of coordinates is greater than 3. Therefore, the final result of this embodiment is that there are four continuous blocks, and only one of them satisfies the condition that the number is greater than 3, namely GroupList[1].

[0076] In addition, the analysis steps using the existing recursive method are as follows:

[0077] Starting from the coordinate (0, 0), traverse the array elements one by one from left to right and from top to bottom. When traversing to element 0, continue to go deeper and look for other elements 0 in the 8-connected domain range, and record the coordinates of these element 0s in a list until there are no more elements. Then traverse to the next element. The specific process is as follows:

[0078] 1.1 If the element at coordinate (0, 0) is 0, a new list GroupList[0] containing coordinate (0, 0) is created. There are three coordinates (0, 1), (1, 0), and (1, 1) in the 8-neighborhood range centered on (0, 0). The element at (1, 1) is 0, so a new coordinate (1, 1) is added to the list GroupList[0]. Now there are two coordinates (0, 0) and (1, 1) in the list.

[0079] Continuing with (1, 1) as the center, there are 8 coordinates in the 8-neighborhood range: (0, 0), (1, 0), (2, 0), (0, 1), (2, 1), (0, 2), (1, 2), (2, 2). Excluding (0, 0) which is already included in the list, there is no element 0 at other coordinates.

[0080] Then we get the first continuous block GroupList[0], which contains (0, 0) and (1, 1), a total of 2 coordinates;

[0081] 1.2 The element at coordinate (1, 0) is 1, so skip it;

[0082] 1.3 The element at coordinate (2, 0) is 1, so skip it;

[0083] 1.4 The element at coordinate (3, 0) is 0, so a new list GroupList[1] containing coordinate (3, 0) is created. In the 8-neighborhood range around (3, 0), there are 5 coordinates (2, 0), (4, 0), (2, 1), (3, 1), (4, 1). Among them, the elements at (4, 0) and (3, 1) are 0, so these two coordinates are added to the list GroupList[1]. Now there are 3 coordinates in the list (3, 0), (4, 0), (3, 1).

[0084] Continue to use (4, 0) and (3, 1) as the center and find the 0 in the corresponding 8 area;

[0085] With (4,0) as the center, there are 3 coordinates (3,0), (3,1), and (4,1) in the 8-neighborhood. Excluding (3,0) and (3,1) that are already included in the list, there is no element 0 at other coordinates.

[0086] With (3, 1) as the center, there are 8 coordinates in the 8-neighborhood range: (2, 0), (3, 0), (4, 0), (2, 1), (4, 1), (2, 2), (3, 2), (4, 2). Remove (3, 0), (4, 0), (3, 2), (4, 2) which are already included in the list. The elements are 0, so these two coordinates are added to the list GroupList[1]. At this time, there are 5 coordinates in the list: (3, 0), (4, 0), (3, 1), (3, 2), (4, 2);

[0087] Continue to use (3, 2) and (4, 2) as the center and find the 0 in the corresponding 8 area;

[0088] With (3, 2) as the center, there are 8 coordinates in the 8-neighborhood range: (2, 1), (3, 1), (4, 1), (2, 2), (4, 2), (2, 3), (3, 3), (4, 3). Remove (3, 1) and (4, 2) that are already included in the list. The element on (4, 3) is 0, so it is added to the list GroupList[1]. At this time, there are 6 coordinates in the list: (3, 0), (4, 0), (3, 1), (3, 2), (4, 2), (4, 3);

[0089] Continuing with (4, 3) as the center, there are 5 coordinates in the 8-neighborhood range: (3, 2), (4, 2), (3, 3), (3, 4), (4, 4). Excluding (3, 2) and (4, 2) that are already included in the list, there is no element 0 at the other coordinates;

[0090] Then we get the second continuous block GroupList[1], which contains (3, 0), (4, 0), (3, 1), (3, 2), (4, 2), (4, 3), a total of 6 coordinates;

[0091] 1.5 Similarly, we can get GroupList[2], which contains (0, 4), a total of 1 coordinate; GroupList[3], which contains (2, 4), a total of 1 coordinate.

[0092] 1.6 Count the number of coordinates in the final GroupList[0]-GroupList[3], and obtain the list with the number of coordinates greater than 3. In this example, only one list GroupList[1] meets the condition. Therefore, the final result of this example is that there are four continuous blocks, which meet the condition of this example. There is only one list with the number greater than 3, GroupList[1], which is consistent with the result obtained by the method of the present disclosure above.

[0093] From the specific analysis steps of the recursive method, it can be seen that each element must stop at the boundary of the continuous block, and many elements are analyzed multiple times. However, for the disclosed method, each element is analyzed only once, and the continuous elements in the same row are recorded as a group. The continuity between different rows is processed by equivalent pairs, which greatly reduces the number of analyses and improves the analysis efficiency.

[0094] In addition, the recursive method needs to record all coordinate data during the analysis process. The stronger the continuity of the analyzed data, the greater the pressure on the computer memory. When the continuity exceeds a certain critical value, the memory cannot bear the burden and the program will crash, resulting in the inability to analyze the data normally and output the results.

[0095] In summary, the method disclosed in the present invention is superior to the recursive method in terms of efficiency and stability.

[0096] Below, this disclosure is combined with the attached Figure 2 The specific embodiment given in FIG. 5( c ) further compares and explains the analysis method disclosed in the present invention with the recursive method.

[0097] Figure 2 It is a schematic diagram comparing the time consumption of the method disclosed in the present invention and the recursive method. The figure lists a PC with 16G of running memory, and the time consumption of the existing recursive method and the method disclosed in the present invention when the running data volume is 50*50, 100*100, and 120*120. It can be seen from the figure that the time consumption of the present invention is significantly less than that of the recursive method. When the data volume reaches 150*150 or even larger, the recursive method directly crashes due to memory overflow, but the method disclosed in the present invention can analyze the results within 2-3S. Therefore, it can be explained that the method disclosed in the present invention can improve the analysis speed on the one hand, and reduce memory loss and avoid system crashes on the other hand.

[0098] Furthermore, the present disclosure takes 50*50 array, 100*100 array and 120*120 array as examples, and illustrates the analysis results of the method of the present disclosure and the existing recursive method as follows: wherein, Figure 3(a) is a schematic diagram of the analysis results of the 50*50 array using the method of the present disclosure; Figure 3(b) is a schematic diagram of the analysis results of the 50*50 array using the recursive method; Figure 3(c) is a byte-by-byte comparison of the analysis results shown in Figure 3(a) and Figure 3(b). It can be seen from Figure 3(c) that through byte-by-byte comparison, the analysis results of the two analysis methods are exactly the same.

[0099] Figure 4(a) is a schematic diagram of the analysis results of a 100*100 array using the method described in the present invention; Figure 4(b) is a schematic diagram of the analysis results of a 100*100 array using a recursive method; Figure 4(c) is a byte-by-byte comparison of the analysis results shown in Figures 4(a) and 4(b). It can be seen from Figure 4(c) that through byte-by-byte comparison, the analysis results of the two analysis methods are exactly the same.

[0100] Figure 5(a) is a schematic diagram of the analysis results of a 120*120 array using the method described in the present invention; Figure 5(b) is a schematic diagram of the analysis results of a 120*120 array using a recursive method; Figure 5(c) is a byte-by-byte comparison of the analysis results shown in Figure 5(a) and Figure 5(b). It can be seen from Figure 5(c) that through byte-by-byte comparison, the analysis results of the two analysis methods are exactly the same.

[0101] In summary, by combining Figure 2 and Figures 3(a) to 3(c) , Figures 4(a) to 4(c) and Figures 5(a) to 5(c)It can be shown that the method disclosed in the present invention can not only improve the array analysis speed and reduce memory loss, but also obtain analysis results consistent with the existing recursive method.

[0102] In addition, the present invention also discloses a wafer continuous result analysis device, comprising:

[0103] The group marking unit is used to obtain the two-dimensional array of wafer test results, traverse the array row by row, select and record the continuous 0 elements in each row and record them as a group;

[0104] The list acquisition unit is used to record the coordinates of each group in the two-dimensional array and number all groups. After traversing the array row by row, the group list is obtained.

[0105] List traversal unit, used to traverse the group list row by row according to the vertical coordinate;

[0106] The continuous block obtaining unit is used to re-count the group list after traversing row by row to obtain the final continuous block.

[0107] Preferably, in the group marking unit, in each row of the array, the number of 0 elements is greater than or equal to 1, and each is recorded as a group.

[0108] Preferably, in the list traversal unit, a group with a vertical coordinate of 1 is selected to start traversing the group list row by row.

[0109] Preferably, in the list traversal unit, in the process of traversing the group list row by row according to the vertical coordinate, the numbers corresponding to the groups whose coordinates are located on a straight line in two adjacent rows are recorded as an equivalent pair.

[0110] Preferably, in the continuous block obtaining unit, a list whose coordinate quantity meets the requirement in the re-counted group list is selected as the final continuous block.

[0111] Although the present invention has been described in detail above by general description and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements can be made to the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all belong to the scope of protection claimed by the present invention.

Claims

1. A wafer continuous result analysis method, comprising the following steps: S100: Obtain a two-dimensional array of wafer test results. In the array, 0 represents FAIL and 1 represents PASS. The array is traversed row by row to determine whether it is 0 according to the screening condition. In each row of the array, the number of 0 elements is greater than or equal to 1, and each is recorded as a group. S200: Record the coordinates of each group in the two-dimensional array, number all groups, and obtain a group list after traversing the array row by row; S300: Select the group with a vertical coordinate of 1 and start traversing the group list row by row, and compare whether the coordinates of each row of groups are on a straight line with the coordinates of the previous row of groups. The straight line includes any one of a parallel line, a vertical line and an oblique line. If they are on a straight line, they are called adjacent. The numbers corresponding to the groups on a straight line in the adjacent rows are recorded as equivalent pairs, otherwise, no equivalent pair is recorded; sort out all equivalent pairs, count the equivalent numbers as a large group, so as to obtain the final equivalent relationship, and record the coordinates in the groups with equivalent numbers into the same list; S400: Count the number of coordinates in the final group, and select the list of coordinates in the re-counted group list that meets the conditions as the final continuous block.

2. A device for implementing the wafer continuous result analysis method as claimed in claim 1, comprising: The group marking unit is used to obtain a two-dimensional array of wafer test results. In the array, 0 represents FAIL and 1 represents PASS. The array is traversed row by row to determine whether it is 0 according to the screening condition. In each row of the array, if the number of 0 elements is greater than or equal to 1, they are all recorded as a group. The list acquisition unit is used to record the coordinates of each group in the two-dimensional array and number all groups. After traversing the array row by row, the group list is obtained. A list traversal unit is used to select a group with a vertical coordinate of 1 and start traversing the group list row by row, comparing whether the line connecting the coordinates of each row of groups with the coordinates of the previous row of groups is located on a straight line, wherein the straight line includes any one of a parallel line, a vertical line and an oblique line. If they are located on a straight line, they are called adjacent, and the numbers corresponding to the groups located on a straight line in the adjacent rows are recorded as equivalent pairs, otherwise, no equivalent pair is recorded; sorting out all equivalent pairs, counting equivalent numbers into a large group, so as to obtain the final equivalent relationship, and recording the coordinates in the groups with equivalent numbers into the same list; The continuous block obtaining unit is used to count the number of coordinates in the final group, and select the list of coordinates in the re-counted group list that meets the conditions as the final continuous block; in, In the group tag unit, in each row of the array, the number of 0 elements is greater than or equal to 1, and they are all recorded as a group; In the list traversal unit, select the group with a vertical coordinate of 1 and start traversing the group list row by row.

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