A method, device, equipment and medium for selecting wafer test batches

Abstract

The present application provides a method, device, equipment and medium for selecting a wafer test batch. The method obtains the test information of the target process station after monitoring any wafer batch arriving at the target process station. And based on the test information, a first relative error value for treating the newly arrived wafer batch as a test wafer batch and a second relative error value for not treating the wafer batch as a test wafer batch are calculated. The relative error can reflect the reliability of the measurement, so the first relative error value and the second relative error value can be compared to determine whether to use the wafer batch as a test batch. The above process can alleviate the problem of using wafer batches that do not meet the test requirements for testing in the related art, and there is no need to reset the selection logic for the test batch when the demand ratio of the process station is updated.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of semiconductor equipment manufacturing, and specifically to a method, device, equipment and medium for selecting a wafer test batch. Background Art

[0002] In order to improve the product yield in the process production of semiconductor equipment, some process stations need to select a part of the received wafer batches for process testing (TECN). In actual applications, relevant personnel often set the test demand ratio for the station. That is, the ratio of the number of batches used for testing by the station to the total number of batches entering the station. Then, conventional methods such as selecting according to the tail code of the wafer lot (Lot), selecting according to the arrival order of the wafer lot, and selecting from a fixed batch number cycle are used to select the wafer lot for testing.

[0003] In actual applications, there are often some wafer batches that do not meet the test requirements on the production line. The above selection method may use wafer batches that do not meet the test requirements for testing, thereby affecting process efficiency and product yield. And when the demand ratio of the process station is updated, the above selection method needs to reset the selection logic of the test batch, such as re-specifying the order of arrival selection, resetting the cycle range and the number of selections within the cycle, etc. Summary of the invention

[0004] The embodiment of the present application provides a method, device, equipment and medium for selecting wafer test batches, which are used to select wafer test batches in a process station to improve process efficiency and product yield. When the demand ratio of the process station is updated, there is no need to reset the selection logic of the test batch.

[0005] To achieve the above purpose, the technical solution of the embodiment of the present application is implemented as follows:

[0006] In a first aspect, an embodiment of the present application provides a method for selecting a wafer test batch, the method comprising:

[0007] After monitoring any wafer batch arriving at a target process station, obtaining test information of the target process station; wherein the test information includes the total number of wafer batches that have arrived at the target process station, the number of test wafer batches selected by the target process station, and the demand ratio of the target process station to the test wafer batches;

[0008] Determine, according to the total number of wafer lots, the number of wafer lots to be tested, and the demand ratio, a first relative error value for using the wafer lot for testing, and a second relative error value for not using the wafer lot for testing;

[0009] Whether to use the wafer lot for testing the target process station is determined according to the first relative error value and the second relative error value.

[0010] In some possible embodiments, before determining the first ratio and the second ratio according to the total number of wafer batches and the number of test wafer batches, the method further includes:

[0011] Determining that the wafer batch meets the preset card control conditions;

[0012] The method further comprises:

[0013] After any wafer batch arrives at the target process station, monitoring whether the wafer batch meets the preset card control condition;

[0014] If the wafer lot does not meet the preset card control condition, the wafer lot will not be used as a test for the target process station.

[0015] In some possible embodiments, the preset card control condition includes at least any one or a combination of the following conditions:

[0016] Condition 1: Whether the batch suffix of the wafer batch is the suffix characterizing the test;

[0017] Condition 2: whether the wafer batch has been tested at the target process station;

[0018] Condition three: whether the total number of tests performed on the wafer batch test is greater than the test number threshold.

[0019] In some possible embodiments, determining, according to the total number of wafer batches, the number of wafer batches to be tested, and the demand ratio, a first relative error value for using the wafer batch for testing, and a second relative error value for not using the wafer batch for testing, comprises:

[0020] Determine, based on the total number of wafer lots and the number of test wafer lots, a first ratio of the number of test wafer lots to the total number of wafer lots when the wafer lot is used for testing, and a second ratio of the number of test wafer lots to the total number of wafer lots when the wafer lot is not used for testing;

[0021] The first relative error value and the second relative error value are determined according to the first ratio, the second ratio and the required ratio.

[0022] In some possible embodiments, determining the first relative error value and the second relative error value according to the first ratio, the second ratio, and the required ratio includes:

[0023] determining a first absolute error value and a second absolute error value according to the first ratio, the second ratio and the required ratio;

[0024] The first relative error value is determined according to the first absolute error value and the required ratio, and the second relative error value is determined according to the second absolute error value and the required ratio.

[0025] In some possible embodiments, determining the first absolute error value and the second absolute error value according to the first ratio, the second ratio, and the required ratio includes:

[0026] The absolute value of the difference between the first ratio and the required ratio is used as the first absolute error value, and the absolute value of the difference between the second ratio and the required ratio is used as the second absolute error value.

[0027] In some possible embodiments, the relative error value is determined by the following formula, where the relative error value includes the first relative error value and the second relative error value:

[0028]

[0029] Among them, Ratio is the required ratio, Ratio1 is the first ratio or the second ratio; when Ratio1 is the first ratio, δ is the first relative error value; when Ratio1 is the second ratio, δ is the second relative error value.

[0030] In some possible embodiments, determining whether to use the wafer batch for testing the target process station according to the first relative error value and the second relative error value includes:

[0031] When the first relative error value is less than or equal to the second relative error value, the wafer batch is used for testing the target process station.

[0032] In some possible embodiments, the wafer batch carries identification information representing the total number of times the wafer batch has participated in the test at each target process station; after determining whether to use the wafer batch for the test of the target process station according to the first relative error value and the second relative error value, the method further includes:

[0033] If it is determined that the wafer batch is used for the test of the target process station, a test identification characterizing the demand ratio is added to the identification information of the wafer batch, and the total number of tests in the identification information is updated.

[0034] In a second aspect, an embodiment of the present application provides a device for selecting a wafer test batch, the device comprising:

[0035] An information module is configured to acquire test information of a target process station after monitoring that any wafer batch has arrived at the target process station; wherein the test information includes the total number of wafer batches that have arrived at the target process station, the number of test wafer batches selected by the target process station, and the demand ratio of the target process station to the test wafer batches;

[0036] an error module configured to determine a first relative error value for using the wafer batch for testing and a second relative error value for not using the wafer batch for testing according to the total number of wafer batches, the number of wafer batches to be tested and the demand ratio;

[0037] The test module is configured to perform a test for determining whether to use the wafer lot for the target process station according to the first relative error value and the second relative error value.

[0038] In some possible embodiments, before determining the first ratio and the second ratio according to the total number of wafer batches and the number of tested wafer batches, the error module is further configured to:

[0039] Determining that the wafer batch meets the preset card control conditions;

[0040] The error module is further configured to:

[0041] After any wafer batch arrives at the target process station, monitoring whether the wafer batch meets the preset card control condition;

[0042] If the wafer lot does not meet the preset card control condition, the wafer lot will not be used as a test for the target process station.

[0043] In some possible embodiments, the preset card control condition includes at least any one or a combination of the following conditions:

[0044] Condition 1: Whether the batch suffix of the wafer batch is the suffix characterizing the test;

[0045] Condition 2: whether the wafer batch has been tested at the target process station;

[0046] Condition three: whether the total number of tests performed on the wafer batch test is greater than the test number threshold.

[0047] In some possible embodiments, the step of determining a first relative error value for using the wafer batch for testing and a second relative error value for not using the wafer batch for testing according to the total number of wafer batches, the number of wafer batches to be tested and the demand ratio is performed, and the error module is configured as follows:

[0048] Determine, based on the total number of wafer lots and the number of test wafer lots, a first ratio of the number of test wafer lots to the total number of wafer lots when the wafer lot is used for testing, and a second ratio of the number of test wafer lots to the total number of wafer lots when the wafer lot is not used for testing;

[0049] The first relative error value and the second relative error value are determined according to the first ratio, the second ratio and the required ratio.

[0050] In some possible embodiments, the determining of the first relative error value and the second relative error value according to the first ratio, the second ratio and the required ratio is performed, and the error module is configured as follows:

[0051] determining a first absolute error value and a second absolute error value according to the first ratio, the second ratio and the required ratio;

[0052] The first relative error value is determined according to the first absolute error value and the required ratio, and the second relative error value is determined according to the second absolute error value and the required ratio.

[0053] In some possible embodiments, to perform the step of determining the first absolute error value and the second absolute error value according to the first ratio, the second ratio and the required ratio, the test module is configured as follows:

[0054] The absolute value of the difference between the first ratio and the required ratio is used as the first absolute error value, and the absolute value of the difference between the second ratio and the required ratio is used as the second absolute error value.

[0055] In some possible embodiments, the relative error value is determined by the following formula, where the relative error value includes the first relative error value and the second relative error value:

[0056]

[0057] Among them, Ratio is the required ratio, Ratio1 is the first ratio or the second ratio; when Ratio1 is the first ratio, δ is the first relative error value; when Ratio1 is the second ratio, δ is the second relative error value.

[0058] In some possible embodiments, the test of determining whether to use the wafer lot for the target process station according to the first relative error value and the second relative error value is performed, and the test module is configured as follows:

[0059] When the first relative error value is less than or equal to the second relative error value, the wafer batch is used for testing the target process station.

[0060] In some possible embodiments, the wafer batch carries identification information representing the total number of times the wafer batch has participated in a test at each target process station; after performing the test of determining whether to use the wafer batch for the target process station according to the first relative error value and the second relative error value, the test module is further configured to:

[0061] If it is determined that the wafer batch is used for the test of the target process station, a test identification characterizing the demand ratio is added to the identification information of the wafer batch, and the total number of tests in the identification information is updated.

[0062] In a third aspect, an embodiment of the present application further provides an electronic device, comprising a memory and a processor, wherein the memory stores a computer program that can be run on the processor, and when the computer program is executed by the processor, the processor implements the steps of any one of the methods in the above-mentioned first aspect.

[0063] In a fourth aspect, an embodiment of the present application further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of any method in the above-mentioned first aspect are implemented.

[0064] In a fifth aspect, an embodiment of the present application provides a computer program product, which includes computer instructions, and the computer instructions are stored in a computer-readable storage medium; when a processor of a computer device reads the computer instructions from the computer-readable storage medium, the processor executes the computer instructions, so that the computer device performs the steps of any method in the above-mentioned first aspect.

[0065] The technical solution provided by the embodiment of the present application obtains the test information of the target process station after monitoring any wafer batch arriving at the target process station. The test information includes the total number of wafer batches currently received by the target process station, the number of test wafer batches selected, and the demand ratio of the target process station to the test wafer batch. According to the above test information, the first relative error value for treating the newly arrived wafer batch as a test wafer batch and the second relative error value for not treating it as a test wafer batch are determined. Since the relative error can reflect the reliability of the measurement, the first relative error value can be compared with the second relative error value to determine whether the wafer batch is used as a test batch. The above process can alleviate the problem of using wafer batches that do not meet the test requirements for testing in the related art, and there is no need to reset the selection logic of the test batch when the demand ratio of the process station is updated.

[0066] Other features and advantages of the present application will be described in the subsequent description, and partly become apparent from the description, or be understood by practicing the present disclosure. The purpose and other advantages of the present application can be realized and obtained by the structures specifically pointed out in the written description, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Figure 1 An overall flow chart of a method for selecting a wafer test batch provided in an embodiment of the present application;

[0068] Figure 2 A schematic diagram of relative error calculation provided in an embodiment of the present application;

[0069] Figure 3 Another relative error calculation schematic diagram provided in an embodiment of the present application;

[0070] Figure 4 A schematic diagram comparing the present application with the traditional selection method provided for the embodiment of the present application;

[0071] Figure 5 A linear graph comparing the present application with the traditional selection method provided for the embodiments of the present application;

[0072] Figure 6 The overall flow chart of the station selection test wafer batch provided in the embodiment of the present application;

[0073] Figure 7 A structural diagram of a wafer test batch selection device 700 provided in an embodiment of the present application;

[0074] Figure 8 A structural diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0075] In order to make the purpose, technical scheme and advantages of the present application clearer, the technical scheme in the embodiment of the present application will be clearly and completely described below in conjunction with the drawings in the embodiment of the present application. Obviously, the described embodiment is only a part of the embodiment of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application. In the absence of conflict, the embodiments in the present application and the features in the embodiments can be arbitrarily combined with each other. In addition, although the logical order is shown in the flow chart, in some cases, the steps shown or described can be performed in an order different from that here.

[0076] The terms "first" and "second" in the specification and claims of the present application and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the term "comprising" and any of their variations are intended to cover non-exclusive protection. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices. "Multiple" in the present application can mean at least two, for example, two, three or more, and the embodiments of the present application are not limited.

[0077] As mentioned above, the current semiconductor manufacturing process mostly uses three conventional methods to select wafer batches for testing, namely, selecting according to the tail code of the wafer batch, selecting according to the arrival order of the wafer batch, and selecting from a fixed batch number cycle. The following is an introduction to these three selection methods.

[0078] The method of selecting according to the tail code of the wafer batch is to set a fixed tail code for the wafer batch to be tested for the process station, and use the wafer batch with the tail code as the wafer batch to be tested. Since the number of tail codes is limited (the tail number is a value of 0 to 9), in order to avoid test conflicts, after a fixed tail code is set for a test at a certain process station, the fixed tail code will no longer be used as a test setting by other process stations. This will have a certain degree of impact on the test efficiency and accuracy, and since the tail codes of each wafer batch on the production line are randomly distributed, a lot of human resources are required to calculate the selection ratio, which may result in problems such as human errors and low efficiency.

[0079] The selection method is based on the order of arrival of wafer batches, that is, the remainder is taken according to the cycle of the wafer batches arriving at the station. For example, when the demand ratio is 10%, every 10 batches of wafer batches are regarded as a cycle, and the wafer batches for testing need to be selected in the manner of the 1st batch, 11th batch, 21st batch, and so on. Since this selection method selects the test wafer batches according to fixed batches, there is a risk that wafer batches that do not meet the test conditions on the production line will be used for testing, which will cause unpredictable risks to the process. In addition, this selection method has restrictions on the demand ratio, and the minimum selection ratio accuracy cannot be less than 10%. And it is necessary to set a regular demand ratio, such as 10%, 15%, 20%, which is a floating ratio in units of 5%. Settings such as 17% and 18% cannot be achieved. The above demand ratios are usually set manually and can be modified at any time according to business needs during the wafer batch process. The demand ratio is a requirement for the actual ratio (Branch Ratio) in the station. For example, a demand ratio of 5% means that the actual ratio used for testing in the station should reach 5%. Branch Ratio is the ratio of the number of test wafer batches used for testing by the station to the total number of wafer batches that have arrived at the station.

[0080] The above-mentioned method of selecting from a fixed number of batches in a cycle is to select the first M batches that meet the test conditions from every N batches of wafers arriving at the station for testing. For example, if every 10 batches of wafers are taken as a cycle, the first M batches that meet the test conditions are selected from every 10 batches of wafers arriving at the station for testing. The problem with this selection method is that if there are not enough wafer batches that meet the test conditions in a single cycle, the actual ratio used for testing in the cycle will be lower than the required ratio.

[0081] Furthermore, if the above situation exists in multiple cycles, the error will be accumulated and affect the online production test. In addition, the cycle setting of wafer batches in this selection method usually does not exceed 20 batches per cycle, because the larger the number of wafer batches in a single cycle, the more concentrated the wafer batches selected for testing by this method will be. The smaller the number of wafer batches in a single cycle, the higher the probability of an error between the above Branch Ratio and the required ratio. Therefore, the selection range of the cycle setting of wafer batches in this selection method is mostly 10 to 20 batches per cycle. This results in a maximum particle selection accuracy (i.e., the above required ratio) of 5%, and can only be an integer multiple of 5%, which leads to low particle selection accuracy and large restrictions.

[0082] In addition, all of the above-mentioned selection methods have a common problem, that is, when the demand ratio of the process station is updated, the above-mentioned selection methods need to reset the selection logic of the test batch, such as re-specifying the order of station selection, re-setting the cycle range and the selection quantity within the cycle, etc., which will cause additional manpower burden and resource loss.

[0083] In order to solve the above problems, the inventive concept of the embodiment of the present application is: after monitoring any wafer batch arriving at the target process station, the test information of the target process station is obtained. The test information includes the total number of wafer batches currently received by the target process station, the number of test wafer batches selected, and the demand ratio of the target process station to the test wafer batch. According to the above test information, the first relative error value for treating the newly arrived wafer batch as a test wafer batch and the second relative error value for not treating it as a test wafer batch are determined. Since the relative error can reflect the reliability of the measurement, the first relative error value and the second relative error value can be compared to determine whether the wafer batch is used as a test batch. The above process can alleviate the problem of using wafer batches that do not meet the test requirements for testing in the related art, and there is no need to reset the selection logic of the test batch when the demand ratio of the process station is updated.

[0084] See also Figure 1 , Figure 1 The overall flow chart of a method for selecting a wafer test batch provided in an embodiment of the present application specifically includes:

[0085] Step 101: After monitoring any wafer batch arriving at a target process station, obtaining test information of the target process station; wherein the test information includes the total number of wafer batches that have arrived at the target process station, the number of test wafer batches selected by the target process station, and the demand ratio of the target process station to the test wafer batches;

[0086] The process station is used to perform process preparation on the semiconductor equipment on the production line. In order to improve the product yield, a certain number of wafer batches need to be set for some process stations for process testing. Such process stations are the target process stations in the above step 101.

[0087] In order to further improve the product yield, the embodiment of the present application sets a preset card control condition for the wafer batch used for testing according to the process requirements in the actual production process. The preset card control condition in the embodiment of the present application includes at least any one or a combination of the following conditions:

[0088] Condition 1: Whether the batch suffix of the wafer batch is the suffix characterizing the test;

[0089] Some manufacturers will pre-set a tail code table (Mapping Table) to record the wafer batches that can be used for testing, that is, the wafer batches with tail codes in the tail code table can be used for test selection at the process station. If the tail code of the newly arrived wafer batch is not in the tail code table, it means that the wafer batch is not suitable for testing, otherwise it will cause unpredictable risks to the process.

[0090] Condition 2: whether the wafer batch has been tested at the target process station;

[0091] According to the process settings, there is a possibility that the wafer batch after the test will return to the process station. In order to improve the test accuracy, the same wafer batch should not be tested multiple times at the same process station. Therefore, when it is detected that the wafer batch has been tested at the target process station, it can be set not to use the wafer batch for the test of the target process station.

[0092] Condition three: whether the total number of tests performed on the wafer batch test is greater than the test number threshold.

[0093] The wafer batch will be sent to multiple process stations along with the processing of the production line, that is, the wafer batch may have been used for testing by multiple target process stations before being sent to the target process station. In order to improve the test accuracy, a reasonable threshold can be set. When the total number of tests of any wafer batch participating in the test exceeds the test number threshold, the wafer batch will no longer be used for testing at any target process station.

[0094] During implementation, a Script program can be used to mount the Script program code for each target process station, and it will be triggered when any wafer batch arrives at the station. Specifically, a test label can be set for the wafer batch by setting the field, and the label can record the tail code of the wafer batch, whether the test of the current target process station has been executed, and the total number of tests that have been performed. Therefore, when any wafer batch arrives at the target process station, the above label is monitored to determine whether the wafer batch meets the above preset card control conditions.

[0095] In the embodiment of the present application, if the wafer batch does not meet any one of the preset card control conditions, the wafer batch will not be used for the test of the current target process station. Correspondingly, when the wafer batch meets all the above preset card control conditions, the wafer batch is judged in step 102, and it is determined through the following step 102 whether the wafer batch is used for the test of the currently arrived target process station.

[0096] Step 102: determining a first relative error value for using the wafer batch for testing and a second relative error value for not using the wafer batch for testing according to the total number of wafer batches, the number of wafer batches to be tested and the demand ratio;

[0097] Before explaining the above step 102, the concept of "relative error" will be explained first.

[0098] Relative error refers to the value obtained by multiplying the ratio of the absolute error caused by the measurement to the agreed true value of the measured value by 100%, expressed as a percentage. Specifically, it is shown in the following formula (1):

[0099]

[0100] Among them, δ is the relative error, △ is the absolute error, y is the actual measurement result, and t is the agreed true value of the measured value. Relative error is used to reflect the reliability of the measurement.

[0101] As described in the above step 101, after the wafer batch arrives at the target process station, the test information of the target process station needs to be obtained. The test information specifically includes the total number of wafer batches that have arrived at the target process station, the number of test wafer batches that have been used for testing by the target process station, and the demand ratio of the target process station to the test requirements.

[0102] The selection of wafer batches for testing in the target process station is regarded as the measurement of data, and the above-mentioned concept of relative error is introduced to obtain. In this measurement process, the agreed measured true value t is the required ratio of the target process station to the test requirements. The actual measurement result is the actual ratio used for testing by the target process station, that is, the aforementioned BranchRatio.

[0103] When executing the above step 102, the relative error value corresponding to the wafer batch is determined by the following formula (2):

[0104]

[0105] Among them, Ratio is the required ratio, Ratio1 is the first ratio or the second ratio; when Ratio1 is the first ratio, δ is the first relative error value; when Ratio1 is the second ratio, δ is the second relative error value.

[0106] During implementation, the first ratio RatioY of the number of test wafer batches to the total number of wafer batches when the wafer batch is used for testing and the second ratio RatioN of the number of test wafer batches to the total number of wafer batches when the wafer batch is not used for testing are determined according to the total number of wafer batches a and the number of test wafer batches b. For example, the total number of wafer batches a is 10, and the number of test wafer batches b is 1. After the current wafer batch arrives at the target process station, the wafer batch a is always updated to 11. If the wafer batch is used for testing, b is updated to 2, and the first ratio is obtained: b / a=2 / 11; correspondingly, if the wafer batch is not used for testing, b does not need to be updated and the value remains 1. At this time, the second ratio is obtained: b / a=1 / 11.

[0107] Then, the first relative error value δY and the second relative error value δN are determined according to the first ratio RatioY, the second ratio RatioN and the required ratio Ratio of the test. Figure 2As shown, by substituting the first ratio RatioY as the true measurement result y and the required ratio Ratio as the agreed measured true value t into the above formula (1), the first absolute error value |RatioY-Ratio| representing the absolute measurement error △ can be obtained. The first absolute error value is the absolute value of the difference between the first ratio and the required ratio. Correspondingly, by substituting the second ratio RatioN as the true measurement result y and the required ratio Ratio as the agreed measured true value t into the above formula (1), the second absolute error value |RatioN-Ratio| of the absolute measurement error △ can be obtained, and the second absolute error value is the absolute value of the difference between the second ratio and the required ratio. Then, through the above formula (2), the first relative error value δY and the second relative error value δN are determined according to the first absolute error value |RatioY-Ratio|, the second absolute error value |RatioN-Ratio| and the required ratio Ratio.

[0108] exist Figure 3 In the application scenario shown, before wafer batch 1 arrives at the target process station A, the test information of the target process station A is: the total number of wafer batches that have arrived at the target process station a=20, the number of test wafer batches that have been used for testing by the target process station b=3, assuming that the demand ratio Ratio of the target process station is 15%, then when wafer batch 1 arrives at the target process station A, the total number of wafer batches that have arrived at the target process station is updated to a=20+1=21.

[0109] Then, a first ratio RatioY=(3+1) / 21 of the number of test wafer batches to the total number of wafer batches when wafer batch 1 is used as a test wafer is calculated, and a second ratio RatioN=3 / 21 of the number of test wafer batches to the total number of wafer batches when wafer batch 1 is not used as a test wafer is calculated. Then, a first relative error value δY=|RatioY-Ratio| / Ratio*100% is determined based on the first ratio RatioY and the required ratio Ratio, and a second relative error value δN=|RatioN-Ratio| / Ratio*100% is determined based on the second ratio RatioN and the required ratio Ratio. Finally, by comparing δY and δN, it is determined according to the following step 103 whether the wafer batch is used for testing.

[0110] Step 103: Determine whether to use the wafer batch for testing the target process station according to the first relative error value and the second relative error value.

[0111] As mentioned above, the relative error is used to reflect the reliability of the measurement. Therefore, if the first relative error value is smaller than the second relative error value, it means that the relative error generated by using the wafer batch for testing is smaller than the relative error generated by not using the wafer batch for testing. In other words, using the wafer batch for testing will be closer to the pre-set required ratio.

[0112] Therefore, when the first relative error value is less than or equal to the second relative error value, the wafer batch can be used for the test of the target process station. Otherwise, the wafer batch is not used for the test of the target process station. That is, if δY≤δN, the wafer batch is used for the test; if δY>δN, the wafer batch is not used for the test.

[0113] Next, Figure 4 As shown, Figure 4 It shows a test of 40 batches with a demand ratio of 20% for the process station as an example, and the selection data comparison of the wafer batch selection is performed by using the method 1 introduced above of selecting according to the order of arrival, the method 2 of selecting from a fixed batch number cycle, and the technical solution of the present application.

[0114] The following explanation is based on every 10 batches as a cycle. First, by comparing the selection data of Method 1 and Method 2, it can be seen that the selection data of Method 1 and Method 2 are the same under ideal conditions. However, when Method 1 encounters wafer batches that do not meet the conditions, it cannot select a test wafer batch that meets the required ratio. Although Method 2 can adapt to this problem to a certain extent within the cycle, it is also unable to select a test wafer batch that meets the required ratio if there are wafer batches that do not meet the conditions continuously.

[0115] For details, see Figure 4 From the selection data of batches 31 to 40, it can be seen that the selection data of method 1 and method 2 are the same under ideal conditions. The so-called ideal state is that there is no current wafer batch that is determined by the process station to be used for testing, but because the wafer batch does not meet the test conditions (i.e. the corresponding Figure 4 Looking back at the selection data of batches 1 to 10, it can be seen that when wafer batches that do not meet the conditions are encountered during the cycle, method 1 cannot select the number of test wafer batches that meet the required ratio. Although method 2 can adapt to a certain extent within the cycle, referring to the selection data of batches 11 to 30, it can be found that when wafer batches that do not meet the conditions appear continuously, method 2 is also unable to select test wafer batches that meet the required ratio.

[0116] Looking at the selection data of this application again, it can be found that the technical solution of this application does not involve the concept of cycle selection. Although there may be situations in which the required ratio is not met within the cycle (for example, this application only selects one batch from the 11 to 20 batches corresponding to cycle 2 for testing, and the required ratio of 20% is not met within this cycle), this application can dynamically adjust the wafer batch used for testing based on the comparison of relative errors, so that the final test accuracy can meet the required ratio to the maximum extent. That is, this application selected a total of 8 batches from the final 40 batches for testing, and the actual ratio is 8 / 40*100%=20%, which meets the requirement of the required ratio of 20%.

[0117] Another example is Figure 5 As shown, Figure 5 Shown above Figure 4 The linear comparison results between the selection data and the required ratio corresponding to each selection method are obtained through Figure 5 It can be seen intuitively that in the entire selection process, the linear curve of the test wafer batch selected by using the technical solution of the present application can be more inclined to the required ratio, the error fluctuation between the entire process and the required ratio is small and the overall fluctuation of the curve is relatively smooth. It can be seen that the technical solution of the present application can greatly reduce the possibility of real-time errors being too large or too small.

[0118] To facilitate understanding of the technical solutions provided in the embodiments of the present application, Figure 6 The flowchart shows the entire selection process after any wafer batch arrives at the target process station, including:

[0119] Step 601: After monitoring any wafer batch arriving at the station, obtain the test information of the station; the test information includes the total number of wafer batches that have arrived at the station, the number of test wafer batches that have been used for testing by the station, and the demand ratio of the station to the test wafer batches.

[0120] Step 602: monitoring whether the wafer batch meets the preset card control conditions;

[0121] Step 603: If the preset card control condition is not met, the wafer batch is not used for testing at this station;

[0122] Step 604: if the preset card control condition is met, then based on the relative error algorithm, determine a first relative error value when the wafer batch is used for the test and a second relative error value when the wafer batch is not used for the test according to the test information;

[0123] Step 605: Determine whether the first relative error value is greater than the second relative error value;

[0124] Step 606: If it is less than or equal to the second relative error value, the wafer batch is used as the test wafer batch of this site; otherwise, the above step 603 is executed to not use the wafer batch for the test of this site.

[0125] The above process obtains the test information of the target process station after monitoring any wafer batch arriving at the target process station. And calculates the first relative error value of the newly arrived wafer batch as the test wafer batch and the second relative error value of not being the test wafer batch based on the test information. Since the relative error can reflect the reliability of the measurement, the first relative error value and the second relative error value can be compared to determine whether the wafer batch is used as a test batch. In this way, the problem of using wafer batches that do not meet the test requirements for testing in the related art is alleviated, and when the demand ratio of the process station is updated, there is no need to reset the selection logic of the test batch.

[0126] As mentioned above, in the embodiment of the present application, identification information for preset card control condition detection is added to the wafer batch. Therefore, when the wafer batch is determined to be used for the test of the target process station through the above process, a test identification indicating that the wafer batch has participated in the test of the current target process station needs to be added to the identification information of the wafer batch, and the total number of tests in the identification information is updated, that is, the total number of tests is increased by one. Therefore, when the wafer batch flows through other target process stations from the production line, other target process stations can verify the card control conditions of the wafer batch according to the updated identification information.

[0127] Based on the same inventive concept, the embodiment of the present application provides a wafer test batch selection device 700, specifically, Figure 7 As shown, including:

[0128] The information module 701 is configured to acquire test information of the target process station after monitoring that any wafer batch has arrived at the target process station; wherein the test information includes the total number of wafer batches that have arrived at the target process station, the number of test wafer batches selected by the target process station, and the demand ratio of the target process station to the test wafer batch;

[0129] The error module 702 is configured to determine a first relative error value for using the wafer batch for testing and a second relative error value for not using the wafer batch for testing according to the total number of wafer batches, the number of wafer batches to be tested and the demand ratio;

[0130] The test module 703 is configured to execute a test to determine whether to use the wafer lot for the target process station according to the first relative error value and the second relative error value.

[0131] In some possible embodiments, before determining the first ratio and the second ratio according to the total number of wafer batches and the number of tested wafer batches, the error module is further configured to:

[0132] Determining that the wafer batch meets the preset card control conditions;

[0133] The error module is further configured to:

[0134] After any wafer batch arrives at the target process station, monitoring whether the wafer batch meets the preset card control condition;

[0135] If the wafer lot does not meet the preset card control condition, the wafer lot will not be used as a test for the target process station.

[0136] In some possible embodiments, the preset card control condition includes at least any one or a combination of the following conditions:

[0137] Condition 1: Whether the batch suffix of the wafer batch is the suffix characterizing the test;

[0138] Condition 2: whether the wafer batch has been tested at the target process station;

[0139] Condition three: whether the total number of tests performed on the wafer batch test is greater than the test number threshold.

[0140] In some possible embodiments, the step of determining a first relative error value for using the wafer batch for testing and a second relative error value for not using the wafer batch for testing according to the total number of wafer batches, the number of wafer batches to be tested and the demand ratio is performed, and the error module is configured as follows:

[0141] Determine, based on the total number of wafer lots and the number of test wafer lots, a first ratio of the number of test wafer lots to the total number of wafer lots when the wafer lot is used for testing, and a second ratio of the number of test wafer lots to the total number of wafer lots when the wafer lot is not used for testing;

[0142] The first relative error value and the second relative error value are determined according to the first ratio, the second ratio and the required ratio.

[0143] In some possible embodiments, the determining of the first relative error value and the second relative error value according to the first ratio, the second ratio and the required ratio is performed, and the error module is configured as follows:

[0144] determining a first absolute error value and a second absolute error value according to the first ratio, the second ratio and the required ratio;

[0145] The first relative error value is determined according to the first absolute error value and the required ratio, and the second relative error value is determined according to the second absolute error value and the required ratio.

[0146] In some possible embodiments, to perform the step of determining the first absolute error value and the second absolute error value according to the first ratio, the second ratio and the required ratio, the test module is configured as follows:

[0147] The absolute value of the difference between the first ratio and the required ratio is used as the first absolute error value, and the absolute value of the difference between the second ratio and the required ratio is used as the second absolute error value.

[0148] In some possible embodiments, the relative error value is determined by the following formula, where the relative error value includes the first relative error value and the second relative error value:

[0149]

[0150] Among them, Ratio is the required ratio, Ratio1 is the first ratio or the second ratio; when Ratio1 is the first ratio, δ is the first relative error value; when Ratio1 is the second ratio, δ is the second relative error value.

[0151] In some possible embodiments, the test of determining whether to use the wafer lot for the target process station according to the first relative error value and the second relative error value is performed, and the test module is configured as follows:

[0152] When the first relative error value is less than or equal to the second relative error value, the wafer batch is used for testing the target process station.

[0153] In some possible embodiments, the wafer batch carries identification information representing the total number of times the wafer batch has participated in a test at each target process station; after performing the test of determining whether to use the wafer batch for the target process station according to the first relative error value and the second relative error value, the test module is further configured to:

[0154] If it is determined that the wafer batch is used for the test of the target process station, a test identification characterizing the demand ratio is added to the identification information of the wafer batch, and the total number of tests in the identification information is updated.

[0155] Refer to the following Figure 8 The electronic device 130 according to this embodiment of the present application is described. Figure 8The electronic device 130 shown is merely an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0156] like Figure 8 As shown, the electronic device 130 is in the form of a general electronic device. The components of the electronic device 130 may include but are not limited to: the at least one processor 131, the at least one memory 132, and a bus 133 connecting different system components (including the memory 132 and the processor 131).

[0157] Bus 133 represents one or more of several types of bus structures, including a memory bus or memory controller, a peripheral bus, a processor, or a local bus using any of a variety of bus architectures.

[0158] The memory 132 may include a readable medium in the form of a volatile memory, such as a random access memory (RAM) 1321 and / or a cache memory 1322 , and may further include a read-only memory (ROM) 1323 .

[0159] The memory 132 may also include a program / utility 1325 having a set (at least one) of program modules 1324, such program modules 1324 including but not limited to: an operating system, one or more application programs, other program modules, and program data, each of which or some combination may include an implementation of a network environment.

[0160] The electronic device 130 may also communicate with one or more external devices 134 (e.g., keyboards, pointing devices, etc.), may also communicate with one or more devices that enable a user to interact with the electronic device 130, and / or communicate with any device that enables the electronic device 130 to communicate with one or more other electronic devices (e.g., routers, modems, etc.). Such communication may be performed via an input / output (I / O) interface 135. Furthermore, the electronic device 130 may also communicate with one or more networks (e.g., a local area network (LAN), a wide area network (WAN), and / or a public network, such as the Internet) via a network adapter 136. As shown, the network adapter 136 communicates with other modules for the electronic device 130 via a bus 133. It should be understood that, although not shown in the figure, other hardware and / or software modules may be used in conjunction with the electronic device 130, including but not limited to: microcode, device drivers, redundant processors, external disk drive arrays, RAID systems, tape drives, and data backup storage systems.

[0161] In an exemplary embodiment, a computer-readable storage medium including instructions is also provided, such as a memory 132 including instructions, and the instructions can be executed by the processor 131 of the above device to complete the above method. Alternatively, the computer-readable storage medium can be a ROM, a random access memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, etc.

[0162] In an exemplary embodiment, a computer program product is also provided, including a computer program / instruction, which, when executed by the processor 131, implements any method in the method for selecting a wafer test batch provided in the present application.

[0163] In an exemplary embodiment, various aspects of a method for selecting a wafer test batch provided in the present application may also be implemented in the form of a program product, which includes program code. When the program product is run on a computer device, the program code is used to enable the computer device to execute the steps of a method for selecting a wafer test batch according to various exemplary embodiments of the present application described above in this specification.

[0164] The program product may employ any combination of one or more readable media. The readable medium may be a readable signal medium or a readable storage medium. The readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination thereof. More specific examples of readable storage media (a non-exhaustive list) include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof.

[0165] The program product for selecting a wafer test batch according to an embodiment of the present application may adopt a portable compact disk read-only memory (CD-ROM) and include program code, and may be run on an electronic device. However, the program product of the present application is not limited thereto, and in this document, a readable storage medium may be any tangible medium containing or storing a program, which may be used by or in combination with an instruction execution system, apparatus, or device.

[0166] A readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, wherein readable program code is carried. Such propagated data signals may take a variety of forms, including, but not limited to, electromagnetic signals, optical signals, or any suitable combination of the foregoing. A readable signal medium may also be any readable medium other than a readable storage medium, which may transmit, propagate, or transfer a program for use by or in conjunction with an instruction execution system, apparatus, or device.

[0167] The program code embodied on the readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

[0168] The program code for performing the operation of the present application can be written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Java, C++, etc., and also conventional procedural programming languages ​​such as language or similar programming languages. The program code can be executed entirely on the user electronic device, partially on the user device, as an independent software package, partially on the user electronic device and partially on the remote electronic device, or completely on the remote electronic device or server. In the case of a remote electronic device, the remote electronic device can be connected to the user electronic device through any type of network, including a local area network (LAN) or a wide area network (WAN), or can be connected to an external electronic device (for example, using an Internet service provider to connect through the Internet).

[0169] It should be noted that, although several units or subunits of the device are mentioned in the above detailed description, this division is merely exemplary and not mandatory. In fact, according to the embodiments of the present application, the features and functions of two or more units described above can be embodied in one unit. Conversely, the features and functions of one unit described above can be further divided into multiple units to be embodied.

[0170] In addition, although the operations of the method of the present application are described in a specific order in the drawings, this does not require or imply that the operations must be performed in this specific order, or that all the operations shown must be performed to achieve the desired results. Additionally or alternatively, some steps may be omitted, multiple steps may be combined into one step, and / or one step may be decomposed into multiple steps.

[0171] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0172] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable image scaling device to produce a machine, so that the instructions executed by the processor of the computer or other programmable image scaling device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0173] These computer program instructions may also be stored in a computer readable memory capable of directing a computer or other programmable image scaling device to operate in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture including an instruction device, the instruction device being implemented in the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0174] These computer program instructions may also be loaded onto a computer or other programmable image scaling device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, whereby the instructions executed on the computer or other programmable device provide for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0175] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0176] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A method for selecting a wafer test batch, It is characterized in that The method comprises: After monitoring any wafer batch arriving at a target process station, obtaining test information of the target process station; wherein the test information includes the total number of wafer batches that have arrived at the target process station, the number of test wafer batches selected by the target process station, and the demand ratio of the target process station to the test wafer batches; Determining a first relative error value for using the wafer batch for testing, and a second relative error value for not using the wafer batch for testing, according to the total number of wafer batches, the number of test wafer batches, and the required ratio, specifically includes: determining a first ratio of the number of test wafer batches to the total number of wafer batches when the wafer batch is used for testing, and a second ratio of the test wafer batch to the total number of wafer batches when the wafer batch is not used for testing, according to the total number of wafer batches and the number of test wafer batches; determining the first relative error value and the second relative error value according to the first ratio, the second ratio, and the required ratio; Whether to use the wafer lot for testing the target process station is determined according to the first relative error value and the second relative error value.

2. The method according to claim 1, It is characterized in that Before determining the first ratio and the second ratio according to the total number of wafer batches and the number of test wafer batches, the method further includes: Determining that the wafer batch meets the preset card control conditions; The method further comprises: After any wafer batch arrives at the target process station, monitoring whether the wafer batch meets the preset card control condition; If the wafer lot does not meet the preset card control condition, the wafer lot will not be used as a test for the target process station.

3. The method according to claim 2, It is characterized in that The preset card control conditions include at least any one or a combination of the following conditions: Condition 1: Whether the batch suffix of the wafer batch is the suffix characterizing the test; Condition 2: whether the wafer batch has been tested at the target process station; Condition three: whether the total number of tests performed on the wafer batch test is greater than the test number threshold.

4. The method according to claim 1, It is characterized in that The determining the first relative error value and the second relative error value according to the first ratio, the second ratio and the required ratio includes: determining a first absolute error value and a second absolute error value according to the first ratio, the second ratio and the required ratio; The first relative error value is determined according to the first absolute error value and the required ratio, and the second relative error value is determined according to the second absolute error value and the required ratio.

5. The method according to claim 4, It is characterized in that The determining the first absolute error value and the second absolute error value according to the first ratio, the second ratio and the required ratio includes: The absolute value of the difference between the first ratio and the required ratio is used as the first absolute error value, and the absolute value of the difference between the second ratio and the required ratio is used as the second absolute error value.

6. The method according to claim 1, It is characterized in that The relative error value is determined by the following formula, where the relative error value includes the first relative error value and the second relative error value: Wherein, Ratio is the required ratio, Ratio1 is the first ratio or the second ratio; when Ratio1 is the first ratio, is the first relative error value; when Ratio1 is the second ratio, is the second relative error value.

7. The method according to claim 1, It is characterized in that The step of determining whether to use the wafer batch for testing the target process station according to the first relative error value and the second relative error value includes: When the first relative error value is less than or equal to the second relative error value, the wafer batch is used for testing the target process station.

8. The method according to any one of claims 1 to 7, It is characterized in that The wafer batch carries identification information characterizing the total number of times the wafer batch has participated in the test at each target process station; after determining whether to use the wafer batch for the test of the target process station according to the first relative error value and the second relative error value, the method further includes: If it is determined that the wafer batch is used for the test of the target process station, a test identification characterizing the demand ratio is added to the identification information of the wafer batch, and the total number of tests in the identification information is updated.

9. A device for selecting wafer test batches, It is characterized in that The device comprises: An information module is configured to acquire test information of a target process station after monitoring that any wafer batch has arrived at the target process station; wherein the test information includes the total number of wafer batches that have arrived at the target process station, the number of test wafer batches selected by the target process station, and the demand ratio of the target process station to the test wafer batches; The error module is configured to determine a first relative error value for using the wafer batch for testing, and a second relative error value for not using the wafer batch for testing, according to the total number of wafer batches, the number of test wafer batches, and the required ratio, specifically comprising: determining a first ratio of the number of test wafer batches to the total number of wafer batches when the wafer batch is used for testing, and a second ratio of the test wafer batch to the total number of wafer batches when the wafer batch is not used for testing, according to the total number of wafer batches and the number of test wafer batches; determining the first relative error value and the second relative error value according to the first ratio, the second ratio, and the required ratio; The test module is configured to perform a test for determining whether to use the wafer lot for the target process station according to the first relative error value and the second relative error value.

10. An electronic device, It is characterized in that include: A memory for storing program instructions; A processor is used to call the program instructions stored in the memory, and execute the steps included in any one of the methods of claims 1-8 according to the obtained program instructions.

11. A computer-readable storage medium, It is characterized in that The computer-readable storage medium stores a computer program, wherein the computer program includes program instructions, and when the program instructions are executed by a computer, the computer executes the method according to any one of claims 1 to 8.

12. A computer program product, It is characterized in that The computer program product comprises: a computer program code, and when the computer program code is run on a computer, the computer is caused to execute the method according to any one of claims 1 to 8.

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