Method, device, equipment and storage medium for detecting laser marking on wafer surface

Abstract

An embodiment of the present invention discloses a method, device, equipment and storage medium for detecting laser marking on the surface of a wafer; the method includes: pre-acquiring various abnormal types of marking codes on the surface of the wafer; using an OCR recognition system to read the marking code on the surface of the wafer to be tested, and determining the potential abnormal type corresponding to the marking code according to the reading result; using a CCD recognition system to collect image information of the marking code on the surface of the wafer to be tested, and determining the actual abnormal type corresponding to the marking code according to the image information and the potential abnormal type according to the set determination rules.

Description

Technical Field

[0001] Embodiments of the present invention relate to the field of semiconductor processing technologies, and in particular, to a method, device, equipment, and storage medium for detecting laser marking on the surface of a wafer. Background Art

[0002] Currently, in order to facilitate communication during the wafer processing and manufacturing process and effectively track the history of the wafer, it is generally necessary to uniformly identify the wafer. Usually, laser marking coding technology is used. Specifically, hard marking and soft marking are performed on the wafer according to different processing technology requirements. The operation is to focus the laser beam to leave melted laser pits on the wafer surface, and these laser pit dot matrices are arranged into various required characters. Generally, hard marking is usually performed on the back of the wafer after the wafer sawing and chamfering processes, and soft marking is usually performed on the front of the wafer after the polishing process. The laser marking of the wafer is performed according to the two characters and area requirements of the SEMI standard M12 / T7. Refer to Figure 1 , which shows the laser marking area and laser marking parameters on the back of the wafer. Among them, A represents the Edge Exclusion Area; B represents the FQA (Fixed Quality Area) Boundary; C represents the Edge Profile Region; D represents the Notch; E represents the Wafer Periphery; F represents the Reference Point of the SEMI T7 Mark; G represents the A / N Read Reaction; the dotted line H represents the orientation reference axis, that is, the crystal orientation

[011] ± 1.0° (Orientation Fiducial Axis,

[011] ± 1.0°); the dotted line J represents a 5.0° ± 0.1° offset relative to the orientation reference axis, where θ = 265° (θ = 265°, 5.0° ± 0.1° from Orientation Fiducial Axis).

[0003] Currently, each wafer fab usually reads the marking code on the wafer surface through a wafer label reader, and then verifies it with the Manufacturing Execution System (MES) to ensure the consistency between the physical object and the information. The commonly used wafer label reader utilizes an Optical Character Recognition (OCR) system for text recognition to achieve the recognition and reading of the marking code on the wafer surface. On the other hand, when the wafer label reader outputs the result, it scores the code reading and recognition result (with a full score of 400 points), and a score lower than 360 points is judged as NG. Therefore, currently, after the code reading fails, the process personnel still need to manually confirm the result, and there is no precise and detailed classification standard for the code reading failure results in different situations, so it is impossible to specifically judge and analyze the marking situation on the wafer surface. Summary of the Invention

[0004] In view of this, embodiments of the present invention are expected to provide a method, device, equipment, and storage medium for detecting laser marking on the wafer surface; it can automatically determine the abnormal type corresponding to the marking code on the wafer surface, improve the automation degree of wafer detection, and increase production efficiency.

[0005] The technical solution of the embodiments of the present invention is implemented as follows:

[0006] In a first aspect, an embodiment of the present invention provides a method for detecting laser marking on the wafer surface, the method including:

[0007] Pre-obtain various abnormal types of the marking code on the wafer surface;

[0008] Use the OCR recognition system to read the marking code on the surface of the wafer to be tested, and determine the potential abnormal type corresponding to the marking code according to the reading result;

[0009] Use a Charge Coupled Device (CCD) recognition system to collect the image information of the marking code on the surface of the wafer to be tested, and based on the image information and the potential abnormal type, determine the actual abnormal type corresponding to the marking code according to the set determination rules.

[0010] In a second aspect, an embodiment of the present invention provides a device for detecting laser marking on the wafer surface, the device including: an acquisition part, a first determination part, and a second determination part; wherein,

[0011] The acquisition part is configured to pre-obtain various abnormal types of the marking code on the wafer surface;

[0012] The first determination part is configured to use an OCR recognition system to read the marking code on the surface of the wafer to be tested, and determine the potential abnormal type corresponding to the marking code according to the reading result;

[0013] The second determination part is configured to use a CCD recognition system to collect the image information of the marking code on the surface of the wafer to be tested, and determine the actual abnormal type corresponding to the marking code according to the set determination rules based on the image information and the potential abnormal type.

[0014] In a third aspect, an embodiment of the present invention provides a device for detecting laser marking on the surface of a wafer. The device includes: an OCR recognition system, a CCD recognition system, a memory, and a processor; wherein,

[0015] The OCR recognition system is used to read the marking code on the surface of the wafer to be tested;

[0016] The CCD recognition system is used to collect the image information of the marking code on the surface of the wafer to be tested;

[0017] The memory is used to store a computer program that can run on the processor;

[0018] The processor is used to execute the following steps when running the computer program:

[0019] Pre-acquire various abnormal types of the marking code on the surface of the wafer;

[0020] Determine the potential abnormal type corresponding to the marking code according to the reading result;

[0021] Based on the image information and the potential abnormal type, determine the actual abnormal type corresponding to the marking code according to the set determination rules.

[0022] In a fourth aspect, an embodiment of the present invention provides a storage medium. The storage medium stores a program for detecting laser marking on the surface of a wafer. When the program for detecting laser marking on the surface of a wafer is executed by at least one processor, the steps of the method for detecting laser marking on the surface of a wafer described in the first aspect are implemented.

[0023] The embodiment of the present invention provides a method, device, equipment and storage medium for detecting laser marking on the surface of a wafer; by obtaining in advance a variety of abnormal types that may be generated by marking codes on the surface of the wafer, and then for the wafer to be tested, using the OCR recognition system in the wafer barcode reader to read the marking code on the surface of the wafer to be tested, and judging the potential abnormal type corresponding to the marking code based on the reading result, and then using the CCD recognition system in the wafer barcode reader to collect image information of the marking code on the surface of the wafer to be tested, and based on the image information and the potential abnormal type, judging the actual abnormal type corresponding to the marking code according to the set judgment rules. Based on the technical solution provided by the embodiment of the present invention, the OCR recognition system and the CCD recognition system can be used to work together to automatically obtain the specific abnormal type of the wafer surface marking code based on the collected data information and image information, thereby improving the degree of automation of wafer detection and improving production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of the laser marking area and laser marking parameters on the back side of a wafer provided in an embodiment of the present invention;

[0025] Figure 2 A schematic structural diagram of a modified wafer barcode reader provided by an embodiment of the present invention;

[0026] Figure 3 A schematic flow chart of a method for detecting laser marking on a wafer surface provided by an embodiment of the present invention;

[0027] Figure 4 A schematic diagram of marking area division provided by an embodiment of the present invention;

[0028] Figure 5 A schematic diagram of a coordinate system of the upper left corner vertex of a rectangular area corresponding to a marking code provided in an embodiment of the present invention relative to the upper left corner vertex of an image;

[0029] Figure 6 A schematic diagram of parameter positions in the EBBIS determination rule provided by an embodiment of the present invention;

[0030] Figure 7 A schematic diagram of the composition of a device for detecting laser marking on a wafer surface provided by an embodiment of the present invention;

[0031] Figure 8 A schematic diagram of the hardware structure of a device for detecting laser marking on a wafer surface provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0033] Currently, for the operation of reading the marking code on the wafer surface, it is read by a wafer code reader, and the OCR recognition system in the wafer code reader is used for character recognition to identify the situation of the marking code on the wafer surface. Understandably, the OCR recognition system for character recognition means using an electronic device to check the character code marked on the wafer surface, and then using a character recognition method to translate the character shape on the wafer surface into computer text, that is, scanning the coded text on the wafer surface, and then analyzing and processing the scanned image file to obtain the text information. However, currently, not only does the process personnel need to manually confirm the result in case of failure to read the marking code on the wafer surface; moreover, limited by the fact that the wafer code reader is only equipped with an OCR recognition system, for different situations of reading failure, it is impossible to accurately and specifically classify and identify them.

[0034] Based on the above description, it is expected that in the embodiments of the present invention, by adding a CCD recognition system, the linkage with the OCR recognition system of the wafer code reader can be achieved. Understandably, the visual dimension measurement of the CCD recognition system is based on the relative measurement method, and the specific external dimension is determined by using traceability, enlarged calibration, intelligent edge enhancement, and display pattern measurement. In high-precision measurement, the enlargement multiple must meet 35 times or higher to meet the micron-level precision. Therefore, in the digital and automated industry where the fineness and precision standards of industrial product production are getting higher and higher, the CCD recognition system is a very efficient on-line detection method in industrial product detection. In the embodiments of the present invention, the OCR lens of the wafer code reader is modified into an OCR / CCD combined lens. Since the wafer code reader comes with a locator, the CCD recognition system does not need to be equipped with a positioning device, and only a measurement or recognition system needs to be added. It should be noted that in the specific implementation process, the OCR calibration of the composite lens is carried out to ensure that it can normally recognize and score the laser marking; at the same time, the CCD recognition system calibration is carried out to ensure that the CCD recognition system can recognize the laser pits generated during laser marking. The modified wafer code reader 2 is specifically as Figure 2 shown, where ① represents the upper OCR / CCD combined lens; ② represents the lower OCR / CCD combined lens; ③ represents the wafer lifting device; ④ represents the wafer locator.

[0035] See Figure 3 , which shows a method for detecting laser marking on the wafer surface provided by the embodiments of the present invention. The method includes:

[0036] S301. Pre-acquire various abnormal types of the marking code on the wafer surface;

[0037] S302. Use the OCR recognition system to read the marking code on the surface of the wafer to be tested, and determine the potential abnormal type corresponding to the marking code according to the reading result;

[0038] S303. Use a CCD recognition system to collect the image information of the marking code on the surface of the to-be-tested wafer, and based on the image information and the potential abnormal type, determine the actual abnormal type corresponding to the marking code according to the set determination rules.

[0039] It can be understood that for the above technical solution, step S301 can be considered as obtaining in advance the possible abnormal types that the marking code on the surface of the to-be-tested wafer may have before detecting the marking code on the surface of the to-be-tested wafer.

[0040] For Figure 3 the above technical solution, by obtaining in advance various abnormal types that the marking code on the surface of the wafer will generate, and then for the to-be-tested wafer, use the OCR recognition system in the wafer code reader to read the marking code on the surface of the to-be-tested wafer, and determine the potential abnormal type corresponding to the marking code according to the reading result. Furthermore, use the CCD recognition system in the wafer code reader to collect the image information of the marking code on the surface of the to-be-tested wafer, and based on the image information and the potential abnormal type, determine the actual abnormal type corresponding to the marking code according to the set determination rules. Based on Figure 3 the above technical solution, it is possible to link the OCR recognition system and the CCD recognition system to automatically obtain the specific abnormal type of the marking code on the surface of the wafer according to the collected data information and image information, improving the automation degree of wafer detection and the production efficiency.

[0041] For Figure 3 the above technical solution, in some possible implementation manners, the obtaining in advance various abnormal types of the marking code on the surface of the wafer includes:

[0042] Based on the M12 / T7 character type, the abnormal types of the marking code on the surface of the wafer include: glyph deformation, marking smear, marking offset, marking contamination / pit, M12 code missing, T7 code missing, M12&T7 code missing, marking scratch.

[0043] It should be noted that in the embodiments of the present invention, the abnormal types of the marking codes on the wafer surface obtained in advance can be statistically analyzed based on a large amount of existing data on the failure of reading the marking codes on the wafer. Specifically, when the abnormal type is glyph deformation, it indicates that the glyph of the marking code does not conform to the SEMI standard; when the abnormal type is smudged marking, it indicates that the laser pits corresponding to the marking code have burning marks due to excessive laser intensity, affecting code reading; when the abnormal type is marking offset, it indicates that the marking position does not conform to the SEMI standard; when the abnormal type is marking contamination / pit, it indicates that there is chemical contamination or pit-shaped mechanical damage near the marking; when the abnormal type is missing M12 code, it indicates that no M12 code is found during code reading; when the abnormal type is missing T7 code, it indicates that no T7 code is found during code reading; when the abnormal type is missing M12&T7 codes, it indicates that no M12&T7 codes are found during code reading; when the abnormal type is marking scratch, it indicates that there is a scratch near the marking. For a summary of specific abnormal types, see Table 1 below.

[0044] Table 1

[0045]

[0046] For Figure 3 For the above technical solution, in some possible implementation manners, the method of using the OCR recognition system to read the marking code on the surface of the wafer to be tested and determining the potential abnormal type corresponding to the marking code according to the reading result includes:

[0047] Using the OCR recognition system to read the marking code on the surface of the wafer to be tested, and determining the potential abnormal type corresponding to the marking code according to the reading result includes the following situations:

[0048] When scoring according to the reading result and the score is less than the set score value, the potential abnormal type of the marking code is: glyph deformation, or smudged marking, or marking contamination / pit, or marking scratch;

[0049] When the reading result is blank, the potential abnormal type of the marking code is: marking offset, or missing M12&T7 codes;

[0050] When the M12 code cannot be read out, the potential abnormal type of the marking code is: missing M12 code;

[0051] When the T7 code cannot be read out, the potential abnormal type of the marking code is: missing T7 code.

[0052] It should be noted that in the embodiments of the present invention, the set score value is 360 points, and the full score is 400 points. In the specific implementation process, the set score value can also be set according to the actual situation, and the embodiments of the present invention do not make specific limitations on this.

[0053] For Figure 3 the above technical solution, in some possible implementation manners, the method for collecting the image information of the marking code on the surface of the wafer to be measured by using a CCD recognition system, and determining the actual abnormal type corresponding to the marking code based on the image information and the potential abnormal type according to the set determination rules includes:

[0054] Based on the collected image information, divide the marking area on the surface of the wafer to be measured into multiple sub-areas according to the laser marking aperture;

[0055] Scan each of the sub-areas in sequence, use the four-point positioning method to check four points in each sub-area to determine the character glyph corresponding to the marking code, and compare the character glyph corresponding to the marking code with the set character glyph. At the same time, use the OCR recognition system to read the character glyph corresponding to the result in the result to verify the comparison result between the character glyph corresponding to the marking code and the set character glyph;

[0056] When the reading result corresponding to the character glyph in the result read by the OCR recognition system is consistent with the comparison result between the character glyph corresponding to the marking code and the set character glyph, use a circle with a set diameter to detect the aperture and morphology of the laser pit corresponding to the marking code;

[0057] When the detection of the aperture and morphology of the laser pit corresponding to the marking code passes, determine the scratch at the position of the marking code;

[0058] Output the actual abnormal type corresponding to the marking code.

[0059] For the above implementation manner, in some examples, the size of each of the areas is 200μm×200μm.

[0060] It should be noted that in the specific implementation process, based on the image collected by the CCD recognition system, the marking area on the wafer surface is divided into areas according to the laser marking aperture. In the embodiment of the present invention, the preferred sub-area division size according to the wafer laser marking aperture is 200μm×200μm, and the marking area is magnified 5 or 10 times. The starting point of the sub-area division and the number of laser pits in the longitudinal / transverse direction of the sub-area can both be set. Refer to Figure 4 , which shows a schematic diagram of the marking area division provided by the embodiment of the present invention. Among them, K represents the divided sub-area of 200μm×200μm.

[0061] Secondly, after the sub-region division is completed, each sub-region is scanned one by one. Since the SEMI standard stipulates the character glyphs of the marking code, in the embodiments of the present invention, the four points in each sub-region are checked by the four-point positioning method to determine the character glyphs corresponding to the marking code on the wafer surface, and the character glyphs corresponding to the marking code on the wafer surface are checked according to the character glyphs stipulated by the SEMI standard, and are verified with the character glyph recognition result fed back by the OCR recognition system. When the character glyph result of the marking code obtained based on the image information is consistent with the character glyph result recognized by the OCR recognition system, it indicates that the verification is passed. After the verification is passed, the aperture and morphology of the laser pit during marking are checked using a set standard circle. Finally, after the aperture and appearance of the laser pit are checked, the scratch defects around the laser drilling are judged, and the judgment result is finally output.

[0062] It can be understood that in the embodiments of the present invention, first, the OCR recognition system is used to detect the abnormal types of the marking codes on the wafer surface. Based on the abnormal types recognized by the OCR recognition system, the specific abnormal types of the marking codes on the wafer surface can be obtained through the CCD recognition system, preventing the occurrence of misjudgment situations. In particular, the judgment of marking offset and marking scratches plays a crucial role in the quality control of wafer marking.

[0063] For the above implementation manner, in some examples, determining the actual abnormal type corresponding to the marking code according to the set judgment rule based on the image information and the potential abnormal type includes:

[0064] When the single character density in the marking code does not conform to the set 5×9 dot matrix rule, and / or the double character density does not conform to the set 10×18 dot matrix rule, it indicates that the actual abnormal type corresponding to the marking code is glyph deformation;

[0065] When the morphology of the laser pit corresponding to the marking code deviates from the circular morphology of the set diameter, it indicates that the actual abnormal type corresponding to the marking code is marking smear;

[0066] When the coordinate value of the upper left vertex of the rectangular area corresponding to the marking code relative to the upper left vertex of the image is compared with the set coordinate standard value and the offset angle is greater than 5.0°±0.1°, it indicates that the actual abnormal type corresponding to the marking code is marking offset;

[0067] When the M12 character glyph cannot be found within the image range, it indicates that the actual abnormal type corresponding to the marking code is M12 label code missing;

[0068] When the T7 character glyph cannot be found within the said image range, it indicates that the actual abnormal type corresponding to the marking code is the absence of the T7 marking code;

[0069] When the M12 & T7 character glyphs cannot be found within the said image range, it indicates that the actual abnormal type corresponding to the marking code is the absence of the M12 & T7 marking codes;

[0070] Based on the determination rules of Edge Back Front Inspection (EBFIS), determine whether the actual abnormal type is marking contamination / pit, or marking scratch.

[0071] It should be noted that the above-set 5×9 dot matrix rule and the set 10×18 dot matrix rule are both regulations in the SEMI standard.

[0072] In addition, as Figure 5 shown, point L represents the upper left vertex of the rectangular area corresponding to the marking code, and point M represents the upper left vertex of the collected image, which is also the origin (0, 0) in the embodiments of the present invention. Therefore, when the coordinate value of the upper left vertex L of the rectangular area corresponding to the marking code relative to the upper left vertex M of the image has an offset angle greater than 5.0°±0.1° in comparison with the set coordinate standard value, that is, Figure 1 shown by the dash-dotted line J in, it indicates that the marking of the marking code is offset. It should be noted that Figure 5 the unit system in is mm.

[0073] Again, the specific EBFIS determination rule is that when there is chemical contamination or pit-shaped mechanical damage or scratch at the marking code, obtain the defective image corresponding to the above chemical contamination or pit-shaped mechanical damage or scratch, and at the same time obtain the rectangle corresponding to the defective image. When the ratio of the height of the rectangle border to the width of the rectangle border is greater than 2, and the filling ratio of the defective image is less than 50%, it is determined that the actual abnormal type at the marking code is marking scratch, otherwise it is chemical contamination or pit-shaped mechanical damage. See Table 2 for details.

[0074] Table 2

[0075]

[0076] Among them, for the position indication and parameter meanings of the relevant parameters in Table 3, reference can be made to Figure 6 and Table 3 respectively. Among them, in Figure 6 N represents the rectangle border; O represents the rectangle center; P represents the ellipse; Q represents the major axis of the ellipse; R represents the minor axis of the ellipse; β represents the ellipse angle.

[0077] Table 3

[0078]

[0079] Based on the above description, in the embodiments of the present invention, the determination criteria for the abnormal types of the marking codes on the wafer surface can be seen in Table 4 below.

[0080] Table 4

[0081]

[0082] Based on the same inventive concept as the foregoing technical solution, see Figure 7 , which shows the composition of a device 70 for detecting laser marking on the wafer surface provided by the embodiments of the present invention. The device 70 includes: an acquisition part 701, a first determination part 702, and a second determination part 703; wherein,

[0083] The acquisition part 701 is configured to pre-acquire various abnormal types of the marking codes on the wafer surface;

[0084] The first determination part 702 is configured to use an OCR recognition system to read the marking code on the surface of the wafer to be tested, and determine the potential abnormal type corresponding to the marking code according to the reading result;

[0085] The second determination part 703 is configured to use a CCD recognition system to collect the image information of the marking code on the surface of the wafer to be tested, and determine the actual abnormal type corresponding to the marking code according to the set determination rules based on the image information and the potential abnormal type.

[0086] In some examples, the acquisition part 701 is configured to:

[0087] Based on the M12 / T7 character type, the abnormal types of the marking codes on the wafer surface include: glyph deformation, marking smear, marking offset, marking contamination / pit, M12 code missing, T7 code missing, M12&T7 code missing, marking scratch.

[0088] In some examples, the first determination part 702 is configured to:

[0089] Use the OCR recognition system to read the marking code on the surface of the wafer to be tested, and determine that the potential abnormal type corresponding to the marking code includes the following situations:

[0090] When scoring according to the reading result and the score is less than the set score value, the potential abnormal type of the marking code is: glyph deformation, or marking smear, or marking contamination / pit, or marking scratch;

[0091] When the read result is blank, the potential abnormal types of the marking code are: marking offset, or missing M12&T7 code;

[0092] When the M12 code cannot be read out, the potential abnormal type of the marking code is: missing M12 code;

[0093] When the T7 code cannot be read out, the potential abnormal type of the marking code is: missing T7 code.

[0094] In some examples, the second determination part 703 is configured to:

[0095] Based on the collected image information, divide the marking area on the surface of the wafer to be measured into multiple sub-areas according to the laser marking aperture;

[0096] Scan each of the sub-areas in sequence, use the four-point positioning method to check four points in each sub-area to determine the character glyph corresponding to the marking code, and compare the character glyph corresponding to the marking code with the set character glyph. At the same time, use the character glyph corresponding to the read result in the OCR recognition system to verify the comparison result between the character glyph corresponding to the marking code and the set character glyph;

[0097] When the read result corresponding to the character glyph in the read result of the OCR recognition system is consistent with the comparison result between the character glyph corresponding to the marking code and the set character glyph, use a circle with a set diameter to detect the aperture and morphology of the laser pit corresponding to the marking code;

[0098] When the aperture and morphology detection of the laser pit corresponding to the marking code passes, determine the scratch at the position of the marking code;

[0099] Output the actual abnormal type corresponding to the marking code.

[0100] In some examples, the second determination part 703 is configured to:

[0101] The size of each sub-area is 200μm×200μm.

[0102] In some examples, the second determination part 703 is further configured to:

[0103] When the single character density in the marking code does not conform to the set 5×9 dot matrix rule, and / or the double character density does not conform to the set 10×18 dot matrix rule, it is characterized that the actual abnormal type corresponding to the marking code is glyph deformation;

[0104] When the morphology of the laser pit corresponding to the marking code deviates from the circular morphology with the set diameter, it indicates that the actual abnormal type corresponding to the marking code is overmarked;

[0105] When the offset angle of the coordinate value of the upper left corner vertex of the rectangular area corresponding to the marking code relative to the upper left corner vertex of the image is greater than 5.0°±0.1° compared with the set coordinate standard value, it indicates that the actual abnormal type corresponding to the marking code is marking offset;

[0106] When the M12 character glyph cannot be found within the image range, it indicates that the actual abnormal type corresponding to the marking code is M12 label missing;

[0107] When the T7 character glyph cannot be found within the image range, it indicates that the actual abnormal type corresponding to the marking code is T7 label missing;

[0108] When the M12&T7 character glyph cannot be found within the image range, it indicates that the actual abnormal type corresponding to the marking code is M12&T7 label missing;

[0109] Based on the edge front and back inspection determination rule, determine whether the actual abnormal type is marking contamination / pit or marking scratch.

[0110] It can be understood that in this embodiment, "part" can be part of a circuit, part of a processor, part of a program or software, etc. Of course, it can also be a unit, and can also be a module or non-modular.

[0111] In addition, each component in this embodiment can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit. The above integrated unit can be implemented in the form of hardware or in the form of a software function module.

[0112] When the integrated unit is implemented in the form of a software functional module and is not sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this embodiment, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) or a processor to execute all or part of the steps of the method described in this embodiment. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROM, Read Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs that can store program codes.

[0113] Therefore, this embodiment provides a computer storage medium. The computer storage medium stores a program for detecting laser marking on the surface of a wafer. When the program for detecting laser marking on the surface of the wafer is executed by at least one processor, the method steps for detecting laser marking on the surface of the wafer described in the above technical solution are implemented.

[0114] According to the above device 70 for detecting laser marking on the surface of a wafer and the computer storage medium, refer to Figure 8 , which shows the specific hardware structure of a device 80 for detecting laser marking on the surface of a wafer that can implement the above device 70 for detecting laser marking on the surface of a wafer provided by an embodiment of the present invention. The device 80 includes: an OCR recognition system 801, a CCD recognition system 802, a memory 803, and a processor 804; each component is coupled together through a bus system 805. It can be understood that the bus system 805 is used to realize the connection and communication between these components. In addition to including a data bus, the bus system 805 also includes a power bus, a control bus, and a status signal bus. However, for the sake of clear illustration, in Figure 8 all kinds of buses are labeled as the bus system 805.

[0115] Among them,

[0116] The OCR recognition system 801 is used to read the marking code on the surface of the wafer to be tested;

[0117] The CCD recognition system 802 is used to collect the image information of the marking code on the surface of the wafer to be tested;

[0118] The memory 803 is used to store a computer program that can run on the processor;

[0119] The processor 804 is configured to perform the following steps when running the computer program:

[0120] Pre-acquire multiple abnormal types of the marking code on the wafer surface;

[0121] Determine the potential abnormal type corresponding to the marking code according to the reading result;

[0122] Based on the image information and the potential abnormal type, determine the actual abnormal type corresponding to the marking code according to the set determination rules.

[0123] It can be understood that the memory 803 in the embodiments of the present invention may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), which is used as an external cache. By way of example but not limitation, many forms of RAM are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchlink dynamic random access memory (SLDRAM), and direct rambus random access memory (DRRAM). The memory 803 of the systems and methods described herein is intended to include but not be limited to these and any other suitable types of memory.

[0124] The processor 804 may be an integrated circuit chip with the ability to process signals. In the implementation process, the steps of the above method can be completed by the integrated logic circuit in the hardware of the processor 804 or instructions in the form of software. The above-mentioned processor 804 may be a general-purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. It can implement or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of the present invention. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc. The steps of the method disclosed in combination with the embodiments of the present invention can be directly embodied as being executed and completed by the hardware decoding processor, or executed and completed by a combination of the hardware and software modules in the decoding processor. The software module may be located in a mature storage medium in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, or an electrically erasable programmable memory, a register, etc. This storage medium is located in the memory 803, and the processor 804 reads the information in the memory 803 and combines its hardware to complete the steps of the above method.

[0125] It can be understood that these embodiments described herein can be implemented using hardware, software, firmware, middleware, microcode, or a combination thereof. For a hardware implementation, the processing unit can be implemented in one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), general-purpose processors, controllers, microcontrollers, microprocessors, other electronic units for performing the functions described in this application, or a combination thereof.

[0126] For a software implementation, the technologies described herein can be implemented by modules (e.g., procedures, functions, etc.) that execute the functions described herein. The software code can be stored in a memory and executed by a processor. The memory can be implemented inside or outside the processor.

[0127] Specifically, when the processor 804 is further configured to run the computer program, it executes the method steps of detecting the laser marking on the wafer surface in the foregoing technical solution, which will not be elaborated here.

[0128] It should be noted that the technical solutions described in the embodiments of the present invention can be arbitrarily combined without conflict.

[0129] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, and all should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A method for detecting laser marking on the surface of a wafer, characterized in that, The method includes: Pre-acquiring multiple abnormal types of the marking code on the wafer surface; Using an optical character recognition system to read the marking code on the surface of the wafer to be tested, and determining the potential abnormal type corresponding to the marking code according to the reading result; Using a charge-coupled device recognition system to collect the image information of the marking code on the surface of the wafer to be tested, and based on the image information and the potential abnormal type, determining the actual abnormal type corresponding to the marking code according to the set determination rules. Among them, the step of using a charge-coupled device recognition system to collect the image information of the marking code on the surface of the wafer to be tested, and based on the image information and the potential abnormal type, determining the actual abnormal type corresponding to the marking code according to the set determination rules includes: Based on the collected image information, dividing the marking area on the surface of the wafer to be tested into multiple sub-regions according to the laser marking aperture; Scanning each of the sub-regions in sequence, using the four-point positioning method to check four points in each sub-region to determine the character glyph corresponding to the marking code, comparing the character glyph corresponding to the marking code with the set character glyph, and at the same time using the character glyph corresponding to the reading result in the reading result of the optical character recognition system to verify the comparison result between the character glyph corresponding to the marking code and the set character glyph; When the reading result corresponding to the character glyph in the reading result of the optical character recognition system is consistent with the comparison result between the character glyph corresponding to the marking code and the set character glyph, detecting the aperture and morphology of the laser pit corresponding to the marking code using a circle with a set diameter; When the detection of the aperture and morphology of the laser pit corresponding to the marking code passes, determining the scratch at the position of the marking code; Outputting the actual abnormal type corresponding to the marking code.

2. The method according to claim 1, characterized in that, The pre-acquiring multiple abnormal types of the marking code on the wafer surface includes: Based on the M12 / T7 character type, the abnormal types of the marking code on the wafer surface include: glyph deformation, marking smear, marking offset, marking contamination / pit, M12 code missing, T7 code missing, M12&T7 code missing, marking scratch.

3. The method according to claim 1, characterized in that, The step of using an optical character recognition system to read the marking code on the surface of the wafer to be tested, and determining the potential abnormal type corresponding to the marking code according to the reading result includes: Using the optical character recognition system to read the marking code on the surface of the wafer to be tested, and determining that the potential abnormal type corresponding to the marking code according to the reading result includes the following situations: When scoring according to the reading result and the score is less than the set score value, the potential abnormal type of the marking code is: glyph deformation, or marking smear, or marking contamination / pit, or marking scratch; When the reading result is blank, the potential abnormal type of the marking code is: marking offset, or M12&T7 code missing; When the M12 code cannot be read out, the potential abnormal type of the marking code is: M12 code missing; When the T7 code cannot be read out, the potential abnormal type of the marking code is: T7 code missing.

4. The method according to claim 1, wherein The size of each of the sub-regions is 200μm × 200μm.

5. The method according to claim 1, wherein Based on the image information and the potential abnormal type, determining the actual abnormal type corresponding to the marking code according to the set determination rules, including: When the single-character density in the marking code does not conform to the set 5×9 dot matrix rule, and / or the double-character density does not conform to the set 10×18 dot matrix rule, it indicates that the actual abnormal type corresponding to the marking code is character shape deformation; When the morphology of the laser pit corresponding to the marking code deviates from the circular morphology with the set diameter, it indicates that the actual abnormal type corresponding to the marking code is marking smear; When the offset angle of the coordinate value of the upper left corner vertex of the rectangular area corresponding to the marking code relative to the upper left corner vertex of the image is greater than 5.0°±0.1° compared with the set coordinate standard value, it indicates that the actual abnormal type corresponding to the marking code is marking offset; When the M12 character shape cannot be found within the image range, it indicates that the actual abnormal type corresponding to the marking code is M12 label code missing; When the T7 character shape cannot be found within the image range, it indicates that the actual abnormal type corresponding to the marking code is T7 label code missing; When the M12&T7 character shape cannot be found within the image range, it indicates that the actual abnormal type corresponding to the marking code is M12&T7 label code missing; Based on the edge back-front inspection determination rule, determining whether the actual abnormal type is marking contamination / pit, or marking scratch.

6. A device for detecting laser marking on the surface of a wafer, characterized in that, The device includes: an acquisition part, a first determination part, and a second determination part; wherein, The acquisition part is configured to pre-acquire various abnormal types of the marking code on the wafer surface; The first determination part is configured to use an optical character recognition system to read the marking code on the surface of the wafer to be tested, and determine the potential abnormal type corresponding to the marking code according to the reading result; The second determination part is configured to use a charge-coupled device recognition system to collect the image information of the marking code on the surface of the wafer to be tested, and based on the image information and the potential abnormal type, determine the actual abnormal type corresponding to the marking code according to the set determination rules, wherein, the second determination part is further configured to: Based on the collected image information, divide the marking area on the surface of the wafer to be tested into multiple sub-regions according to the laser marking aperture; Scan each of the sub-regions in sequence, use the four-point positioning method to check four points in each sub-region to determine the character shape corresponding to the marking code, and compare the character shape corresponding to the marking code with the set character shape, and at the same time use the character shape corresponding to the reading result in the reading result of the optical character recognition system to verify the comparison result between the character shape corresponding to the marking code and the set character shape; When the reading result corresponding to the character glyph in the reading result of the optical character recognition system is consistent with the comparison result between the character glyph corresponding to the marking code and the set character glyph, a circle with a set diameter is used to detect the aperture and morphology of the laser pit corresponding to the marking code; When the detection of the aperture and morphology of the laser pit corresponding to the marking code passes, determine the scratch at the position of the marking code; Output the actual abnormal type corresponding to the marking code.

7. An apparatus for detecting laser marking on the surface of a wafer, characterized in that The device includes: an optical character recognition system, a charge-coupled device recognition system, a memory, and a processor; wherein, The optical character recognition system is used to read the marking code on the surface of the wafer to be tested; The charge-coupled device recognition system is used to collect the image information of the marking code on the surface of the wafer to be tested; The memory is used to store a computer program that can run on the processor; The processor is used to execute the following steps when running the computer program: Pre-acquire various abnormal types of the marking code on the wafer surface; Determine the potential abnormal type corresponding to the marking code according to the reading result; Based on the image information and the potential abnormal type, determine the actual abnormal type corresponding to the marking code according to the set determination rules, wherein, the charge-coupled device recognition system collects the image information of the marking code on the surface of the wafer to be tested, and based on the image information and the potential abnormal type, determines the actual abnormal type corresponding to the marking code according to the set determination rules, including: Based on the collected image information, divide the marking area on the surface of the wafer to be tested into multiple sub-areas according to the laser marking aperture; Scan each of the sub-areas in sequence, use the four-point positioning method to check four points in each sub-area to determine the character glyph corresponding to the marking code, and compare the character glyph corresponding to the marking code with the set character glyph, and at the same time use the reading result corresponding to the character glyph in the reading result of the optical character recognition system to verify the comparison result between the character glyph corresponding to the marking code and the set character glyph; When the reading result corresponding to the character glyph in the reading result of the optical character recognition system is consistent with the comparison result between the character glyph corresponding to the marking code and the set character glyph, a circle with a set diameter is used to detect the aperture and morphology of the laser pit corresponding to the marking code; When the detection of the aperture and morphology of the laser pit corresponding to the marking code passes, determine the scratch at the position of the marking code; Output the actual abnormal type corresponding to the marking code.

8. A storage medium, characterized in that, The storage medium stores a program for detecting laser marking on the wafer surface. When the program for detecting laser marking on the wafer surface is executed by at least one processor, the steps of the method for detecting laser marking on the wafer surface according to any one of claims 1 to 5 are implemented.

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