Recognition and detection device and method for pin-fin heat dissipation substrate of power module

Abstract

The invention discloses an identification and detection device and method for a pin-fin heat dissipation substrate of a power module, the device comprises three parts: a four-station annular index plate, a pin-fin heat dissipation substrate jig and a pin-fin heat dissipation substrate sorting and conveying mechanism, and the identification and detection method based on the device comprises the following steps: putting the pin-fin heat dissipation substrate into the jig on a first station; and the four-station annular index plate is driven to rotate anticlockwise, traceability code scanning for pin-fin heat dissipation substrate identification is carried out at the second station, pin-fin heat dissipation substrate product appearance detection is carried out at the third station, and pin-fin heat dissipation substrate warping degree detection is carried out at the fourth station. And the detection information is associated with a product traceability code, an alarm prompt is given for unqualified products, and the unqualified products are sorted and screened out through the sorting and conveying mechanism. Annular multi-station operation is adopted, the appearance quality and the warping degree of a power module pin fin heat dissipation substrate product needing to be fully detected are automatically detected, the occupied space of equipment is saved, meanwhile, the labor cost is reduced, and the detection efficiency and accuracy are improved.

Description

Technical Field

[0001] The present invention specifically relates to the technical field of power semiconductor heat dissipation substrate detection, and particularly to an identification and detection device and method for a power module pin-fin heat dissipation substrate. Background Art

[0002] With the rapid development of new energy vehicles, photovoltaic power generation, wind power generation and other fields, the market demand for power semiconductor modules is increasing. The development trend of its high power level and high integration brings very strict requirements for its thermal management. Therefore, power semiconductor modules need to be equipped with suitable heat dissipation substrates for use. Taking the main drive inverter module of new energy vehicles as an example, the current mainstream heat dissipation substrate product is a copper pin-fin structure, which is welded to the bottom surface of the liner of the power module. The close fit between the two is crucial for the effective heat dissipation when the power semiconductor module is working.

[0003] Power module pin-fin heat dissipation substrate products usually need to be pre-bent to relieve the thermal stress during welding and cooling. The warpage degree of its pre-processing is a key index of the product. At the same time, the appearance quality of the heat dissipation substrate has a direct impact on the heat conduction characteristics during its use after being installed in the power module. Therefore, all inspections of the above indicators need to be carried out when the heat dissipation substrate leaves the factory, which undoubtedly causes great pressure on the identification and detection of the product.

[0004] At present, the identification and detection method of pin-fin heat dissipation substrate products is an in-line production process. In order for users to identify and trace product information, first, the pin-fin heat dissipation substrate is placed manually according to the anti-fooling mark, and then the two-dimensional code or character code made at the specified position of the product is read, and then it is delivered to the subsequent stations in turn for a series of inspections of the warpage degree and product appearance quality. A large amount of manual labor is required. Moreover, for the situation where there are many product specifications and types but small differences, and the production volume of products is large, such an in-line production process is prone to problems such as misloading of different specifications of products and misloading of qualified products and unqualified products, and it is not conducive to the timely repair of unqualified products, and the detection efficiency is low. Summary of the Invention

[0005] The purpose of the present invention is to provide an identification and detection device and method for a power module pin-fin heat dissipation substrate to solve or partially solve the problems raised in the above background art.

[0006] To achieve the above purpose, the present invention provides the following technical solutions:

[0007] The present invention provides an identification and detection device for a power module pin-fin heat dissipation substrate, including a four-station circular indexing table, a pin-fin heat dissipation substrate fixture and a sorting and conveying mechanism;

[0008] Four needle fin heat sink substrate fixtures are respectively arranged at the four stations of the four-station ring indexing table. The center of the four-station ring indexing table is connected to the main shaft of the rotating motor and is driven to rotate, so that the needle fin heat sink substrate fixtures stay at the first to fourth stations respectively;

[0009] The sorting and conveying mechanism includes a manipulator and three conveyor belts. The bracket of the manipulator is installed between the third station and the fourth station. The first and third conveyor belts are respectively connected to the third station and the fourth station for conveying unqualified products detected. The second conveyor belt is located between the third station and the fourth station for conveying qualified products;

[0010] A barcode scanner is installed above the second station for scanning the product traceability code on the welding surface of the needle fin heat sink substrate and inputting the product information into the detection system;

[0011] A camera is installed above the third station for taking pictures of the welding surface of the needle fin heat sink substrate and transmitting them to the detection system. The detection system performs appearance quality detection on the product welding surface through image analysis. The detection information is stored corresponding to the product traceability code. Products with unqualified appearance quality are separated from the needle fin heat sink substrate fixture onto the first conveyor belt. Products with qualified appearance quality are rotated with the indexing table to the fourth station;

[0012] A laser displacement sensor is installed above the fourth station for detecting the warpage of the welding surface of the needle fin heat sink substrate. The detection information is stored corresponding to the product traceability code. Products with unqualified warpage detection are separated from the needle fin heat sink substrate fixture onto the third conveyor belt. Products with qualified warpage detection are picked up, lifted, and flipped by the manipulator, moved to a specified position below the camera at the third station, and pictures are taken of the needle fin area and the sealing ring area of the heat sink substrate and transmitted to the detection system. The detection system judges whether the appearance quality of the product needle fin area and the sealing ring area is qualified through image analysis. The detection information is stored corresponding to the product traceability code. Unqualified products are sent to the first conveyor belt by the manipulator, and qualified products are sent to the second conveyor belt for subsequent product packaging;

[0013] Specifically, four needle fin heat sink substrate fixtures are arranged in a circular pattern on the outer periphery of the upper end surface of the four-station ring indexing table, spaced 90° from each other. The four-station ring indexing table rotates counterclockwise at equal angles under the drive of the rotating motor and stays at the four stations in turn.

[0014] The size of the needle fin heat sink substrate fixture can be adjusted according to the size of the needle fin heat sink substrate product. Positioning pins are provided at the installation hole positions corresponding to the needle fin heat sink substrate. When the needle fin heat sink substrate is placed on the fixture, the needle fin surface faces downwards, and the needle fins have no contact with the four-station ring indexing table.

[0015] The present invention also provides a method for identifying and detecting a power module needle fin heat sink substrate, including the following steps:

[0016] Step 1, Loading: On the first station of the four-station ring indexing table, adjust the finned heat sink substrate fixture to the corresponding size of the finned heat sink substrate product. Place the finned heat sink substrate product face down with the finned side according to the anti-fooling mark in a directional manner. Subsequently, the indexing table automatically rotates counterclockwise by 90°, and transfers the product to the second station;

[0017] Step 2, Product Traceability Code Reading: A product traceability code is made at a designated position on the welding surface of the finned heat sink substrate. Use the barcode scanner above the second station to read the product traceability code, and input the product information into the storage system for product identification. Subsequently, the indexing table rotates counterclockwise by 90°, and transfers the product to the third station;

[0018] Step 3, First Appearance Quality Inspection: Use the camera above the third station to take a picture of the welding surface of the finned heat sink substrate, perform image analysis through the background program, check whether there are unqualified appearance quality conditions on the product welding surface, store the inspection information in the database, and associate it with the product traceability code; For products with unqualified inspections, an alarm is prompted, and they are separated from the finned heat sink substrate fixture to the first conveyor belt, and the unqualified products are sent out of the inspection system; Subsequently, the indexing table rotates counterclockwise by 90°, and transfers the qualified products or empty fixtures to the fourth station;

[0019] Step 4, Warpage Detection: Use the laser displacement sensor above the fourth station to detect the warpage of the welding surface of the finned heat sink substrate, store the inspection information in the database, and associate it with the product traceability code; For products with unqualified inspections, an alarm is prompted, and they are separated from the finned heat sink substrate fixture to the third conveyor belt, and the unqualified products are sent out of the inspection system. Subsequently, the indexing table rotates counterclockwise by 90°, and transfers the empty fixture back to the first station;

[0020] Step 5, Second Appearance Quality Inspection: The qualified products detected in Step 4 are flipped and moved by the robot between the third station and the fourth station to below the camera of the third station, and pictures are taken of the fin area and the seal ring area of the heat sink substrate. Perform image analysis through the background program to conduct appearance quality inspection on the fin area and the seal ring area of the product. Store the inspection information in the database and associate it with the product traceability code; For products with unqualified inspections, an alarm is prompted, and they are sent to the first conveyor belt by the robot, and the unqualified products are sent out of the inspection system; The qualified products are sent to the second conveyor belt for subsequent product packaging.

[0021] Specifically, the first appearance quality inspection and the second appearance quality inspection are used to judge whether there are unqualified appearance quality conditions on the surface of the finned heat sink substrate, including exposed copper, pits, protrusions, and stains. The warpage detection is used to judge whether the warpage caused by the pre-bending process of the finned heat sink substrate meets the product requirements.

[0022] Specifically, the unqualified appearance quality of the welding surface in the first appearance quality inspection in step 3 includes: the phenomenon of exposed copper, or the existence of pits with a diameter greater than 1.5 mm, or the existence of stains with a diameter greater than 0.5 mm, or the existence of protrusions with a height greater than 0.2 mm.

[0023] Specifically, the unqualified appearance quality of the pin fin area in the second appearance quality inspection in step 5 includes: the phenomenon of exposed copper, or the existence of pits with a diameter greater than 3 mm, or the existence of stains with a diameter greater than 0.5 mm, or the protrusion phenomenon at the top of the pin, or the protrusion height at the root of the pin greater than 0.5 mm.

[0024] Specifically, the unqualified appearance quality of the sealing ring area in the second appearance quality inspection in step 5 includes: the phenomenon of exposed copper, or the existence of pit phenomenon, or the existence of stains with a diameter greater than 0.5 mm, or the existence of protrusions with a height greater than 0.2 mm, or the existence of felt scratches.

[0025] Specifically, in step 4, the warpage detection is carried out by the method of taking points to measure the height. Based on two mutually perpendicular centerlines of the heat dissipation substrate, two lines parallel to the long side and the short side of the heat dissipation substrate are respectively taken, and two endpoints with the same distance from the centerline are taken on each line. The height value of the center point is subtracted from the average height value of the two endpoints, and the warpage values of the long side and the short side of the heat dissipation substrate are calculated according to this method.

[0026] Compared with the prior art, the beneficial effects of the present invention are:

[0027] The present invention adopts a circular multi-station operation, designs an automatic detection device and a supporting program, and automatically detects the appearance quality and warpage of the pin fin heat dissipation substrate products that need to be fully inspected, saving the floor space of the equipment, reducing the labor cost, and improving the detection efficiency and accuracy. Brief Description of the Drawings

[0028] Figure 1 It is a schematic diagram of the circular working stations of the identification and detection device proposed by the present invention.

[0029] Figure 2 It is a schematic front view of the pin fin heat dissipation substrate.

[0030] Figure 3 It is a schematic back view of the pin fin heat dissipation substrate.

[0031] Figure 4 It is a schematic diagram of the warpage detection method. Detailed Embodiment

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

[0033] In an embodiment of the present invention, an identification and detection device for a pin-fin heat dissipation substrate of a power module includes a four-station circular indexing table 1, a pin-fin heat dissipation substrate fixture 2, and a pin-fin heat dissipation substrate sorting and conveying mechanism. As Figure 1 shown, four pin-fin heat dissipation substrate fixtures 2 for placing the pin-fin heat dissipation substrate 7 are arranged in a circular array on the outer periphery of the upper end surface of the four-station circular indexing table 1, spaced 90° from each other. The center of the indexing table is connected to the main shaft 8 of the rotating motor and is driven to rotate counterclockwise at equal angles, and can stay at the first to fourth stations in sequence.

[0034] The size of the pin-fin heat dissipation substrate fixture 2 can be adjusted according to the product size, and positioning pins are provided at the positions of the mounting holes corresponding to the pin-fin heat dissipation substrate. As Figure 2 and Figure 3 shown, the pin-fin heat dissipation substrate 7 includes a welding area 14, a pin-fin area, and a sealing ring area. The pin-fin array 11 and the sealing ring 12 are located on the front side, and the welding area 14 is located on the reverse side (welding surface). Sometimes, a plurality of small bosses 15 are processed in the welding area 14 according to requirements to limit the flow of solder. When the pin-fin heat dissipation substrate 7 is placed on the pin-fin heat dissipation substrate fixture 2, the pin-fin surface (front side) faces downwards, and the pins 11 are not in contact with the four-station circular indexing table 1, so as to ensure that the pins 11 will not be damaged during the identification and detection process.

[0035] The functions of the identification and detection device mainly include the appearance quality detection and warpage detection of the pin-fin heat dissipation substrate. The appearance quality detection is to judge whether there are unqualified appearance quality conditions such as exposed copper, pits, protrusions, stains, etc. on the surface of the pin-fin heat dissipation substrate. The warpage detection is to judge whether the warpage caused by the pre-bending process of the pin-fin heat dissipation substrate meets the product requirements.

[0036] The sorting and conveying mechanism includes a manipulator and three conveyor belts. The bracket 6 of the manipulator is installed between the third station and the fourth station. The first conveyor belt 3 and the third conveyor belt 5 are respectively connected to the third station and the fourth station for screening out products with unqualified appearance quality detection and warpage detection. The second conveyor belt 4 is located between the third station and the fourth station for conveying qualified products.

[0037] To better understand the specific solution of the present application, the present application also provides a method for identifying and detecting a pin-fin heat dissipation substrate of a power module based on the above system. The identification and detection method includes the following steps:

[0038] Step 1: Loading.

[0039] At the first station of the four-station circular indexing table 1, the pin-fin heat dissipation substrate fixture 2 is adjusted to the corresponding size of the pin-fin heat dissipation substrate product 7. According to the anti-fooling mark, the pin-fin heat dissipation substrate product 7 is placed face down in a directional manner. Subsequently, the indexing table 1 will automatically rotate counterclockwise by 90°, and the product will be conveyed to the second station.

[0040] Step 2: Read the product traceability code.

[0041] The product traceability code is made at the designated position on the welding surface (i.e., the reverse side) of the pin-fin heat dissipation substrate according to the product requirements. A barcode scanner fixed above the second station is used to input the product information into the storage system for product identification. Subsequently, the indexing table 1 rotates counterclockwise by 90°, and the product is transferred to the third station.

[0042] Step 3: Take a photo.

[0043] A camera fixed above the third station is used to take a photo of the welding surface of the pin-fin heat dissipation substrate. Through the background program design, check whether there are unqualified appearance quality conditions on the product welding surface, including: the phenomenon of exposed copper, or the existence of pits with a diameter greater than 1.5 mm, or the existence of stains with a diameter greater than 0.5 mm, or the existence of protrusions with a height greater than 0.2 mm, etc.

[0044] The detection information is stored in the database corresponding to the product traceability code. For products with unqualified detection, an alarm is prompted, and they are separated from the pin-fin heat dissipation substrate fixture 2 to the first conveyor belt 3 connected to the third station, and the unqualified products are sent out of the detection system. Subsequently, the indexing table 1 rotates counterclockwise by 90°, and the qualified products or empty fixtures are transferred to the fourth station.

[0045] Step 4: Detect the warpage of the product.

[0046] A laser displacement sensor fixed above the fourth station is used to detect the warpage of the welding surface of the pin-fin heat dissipation substrate. The detection method is as Figure 4 shown. The method of taking point measurements of height is adopted. Taking two mutually perpendicular centerlines of the pin-fin heat dissipation substrate 7 as the reference, two lines parallel to the long side 41 and the short side 42 of the pin-fin heat dissipation substrate are respectively taken, and two lines with the same distance from the centerline are taken on each line. On each line, a center point and two end points with the same distance from the center point are taken. Taking the long side 41 as an example, subtracting the height value of the middle point 50 from the average height value of the two end points 51 and 52 can obtain the warpage of the long side 41. According to this method, the warpage values of the long side 41 and the short side 42 can be calculated based on the height values of the detection points.

[0047] The detection information is stored in the database corresponding to the product traceability code. For products with unqualified detection, an alarm is prompted, and they are separated from the pin-fin heat dissipation substrate fixture 2 to the third conveyor belt 5 connected to the fourth station, and the unqualified products are sent out of the detection system. Subsequently, the indexing table 1 rotates counterclockwise by 90°, and the empty fixture is transferred back to the first station.

[0048] Step 5: Second appearance quality inspection.

[0049] The qualified products in Step 4 are picked up, lifted, and flipped by the robot 66 set between the third station and the fourth station, and moved to the designated position under the camera at the third station to photograph the pin fin area 11 and the sealing ring area 12 of the heat dissipation substrate. Through the background program design, the appearance quality of the product's pin fin area 11 and sealing ring area 12 is detected.

[0050] In the embodiment, the unqualified appearance quality conditions of the pin fin area 11 include: the presence of exposed copper, or the presence of pits with a diameter greater than 3 mm, or the presence of stains with a diameter greater than 0.5 mm, or the presence of protrusions at the top of the pins, or the protrusion height at the root of the pins is greater than 0.5 mm, etc. The unqualified appearance quality conditions of the sealing ring area 12 include the presence of exposed copper, or the presence of pits, or the presence of stains with a diameter greater than 0.5 mm, or the presence of protrusions with a height greater than 0.2 mm, or the presence of obvious depressions that damage deeper layers, that is, sensitive scratches, etc.

[0051] The detection information is stored in the database, corresponding to the product traceability code. For products with unqualified detection, an alarm is given, and the products are sent to the first conveyor belt 3 connected to the third station by the robot to send the unqualified products out of the detection system; the qualified products are sent to the second conveyor belt 4 between the third station and the fourth station for subsequent product packaging.

[0052] The above unqualified detection standards all refer to industry standards or are designed according to the product quality standards of the demander.

[0053] The identification and detection device and detection method proposed by the present invention perform automated detection of the appearance quality and warpage of products that need to be fully inspected through a circular multi-station operation, and at the same time realize product sorting and conveying. Not only does the equipment occupy a small space, but also the labor cost is greatly reduced.

[0054] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting, and the protection scope of the present invention is defined by the appended claims rather than the above description.

Claims

1. A device for identifying and detecting a pin-fin heat dissipation substrate of a power module, comprising: Four-station annular indexing plate, pin-fin heat dissipation substrate fixture and sorting and conveying mechanism; its characteristics are: The four stations on the four-station annular indexing plate are respectively provided with pin-fin heat dissipation substrate fixtures, and the center of the four-station annular indexing plate is connected to the main shaft of the rotating motor and is driven to rotate, so that the pin-fin heat dissipation substrate fixtures stay at stations No. 1 to No. 4 respectively; The sorting and conveying mechanism includes a manipulator and three conveyor belts. The support of the manipulator is installed between the third station and the fourth station. The first and third conveyor belts are respectively connected to the third station and the fourth station for conveying unqualified products. The second conveyor belt is located between the third station and the fourth station for conveying qualified products. A barcode scanner is installed above the second workstation for scanning the product traceability code on the welding surface of the pin-fin heat dissipation substrate and inputting the product information into the detection system; A camera is installed above the No. 3 station for taking pictures of the welding surface of the pin-fin heat dissipation substrate and transmitting them to the detection system. The detection system performs appearance quality detection on the welding surface of the product through image analysis. The detection information is stored in the corresponding product traceability code. Products with unqualified appearance quality are separated from the pin-fin heat dissipation substrate fixture to the first conveyor belt, and products with qualified appearance quality are brought to the No. 4 station along with the rotating index plate. A laser displacement sensor is installed above the fourth station for detecting the warpage of the welding surface of the pin-fin heat dissipation substrate. The detection information is stored in the corresponding product traceability code. Products that fail the warpage detection are separated from the pin-fin heat dissipation substrate fixture to the third conveyor belt. Products that pass the warpage detection are picked up, moved up, and flipped by a robot to a designated position under the camera of the third station. Pictures of the pin-fin area and the sealing ring area of ​​the heat dissipation substrate are taken and transmitted to the detection system. The detection system determines whether the appearance quality of the pin-fin area and the sealing ring area of ​​the product is qualified through image analysis. The detection information is stored in the corresponding product traceability code. Unqualified products are sent to the first conveyor belt by the robot, and qualified products are sent to the second conveyor belt for subsequent product packaging.

2. The identification and detection device for a pin-fin heat dissipation substrate of a power module according to claim 1, characterized in that: Four pin-fin heat dissipation substrate fixtures are arranged in a ring around the outer periphery of the upper end surface of the four-station annular indexing plate, which are 90° apart from each other. The four-station annular indexing plate rotates counterclockwise at equal angles driven by a rotating motor and stays at four stations in turn.

3. The identification and detection device for a pin-fin heat dissipation substrate of a power module according to claim 1, characterized in that: The size of the pin-fin heat sink fixture can be adjusted according to the product size of the pin-fin heat sink. Positioning pins are provided at the mounting hole positions corresponding to the pin-fin heat sink. When the pin-fin heat sink is placed on the fixture, the pin fins face downward and the pin fins have no contact with the four-station annular dividing plate.

4. An identification and detection method using the identification and detection device for a power module pin-fin heat dissipation substrate according to claim 1, characterized in that: The following steps are involved: Step 1, loading: At the No. 1 station of the four-station annular indexing plate, adjust the pin-fin heat sink substrate fixture to the size corresponding to the pin-fin heat sink substrate product, and place the pin-fin heat sink substrate product with the pin-fin side facing down according to the anti-fool mark, and then the indexing plate automatically rotates 90° counterclockwise to transfer the product to the No. 2 station; Step 2, product traceability code reading: a product traceability code is made at a designated position on the welding surface of the pin-fin heat sink substrate. The product traceability code is read by a barcode scanner above the No. 2 station, and the product information is input into the storage system for product identification. Then the indexing plate is rotated 90° counterclockwise to transfer the product to the No. 3 station. Step 3, first appearance quality inspection: Use the camera above the No. 3 station to take a picture of the welding surface of the pin-fin heat dissipation substrate, and perform image analysis through the background program to check whether the product welding surface has unqualified appearance quality. The inspection information is stored in the database and associated with the product traceability code; an alarm is triggered for unqualified products, and they are separated from the pin-fin heat dissipation substrate fixture to the first conveyor belt, and the unqualified products are sent out of the inspection system; then the indexing plate is rotated 90° counterclockwise to convey the qualified products or empty fixtures to the No. 4 station; Step 4, warpage detection: Use the laser displacement sensor above the fourth station to detect the warpage of the welding surface of the pin-fin heat dissipation substrate, store the detection information in the database, and associate the product traceability code; detect unqualified products and alarm, and separate them from the pin-fin heat dissipation substrate fixture to the third conveyor belt, send the unqualified products out of the detection system, then rotate the indexing plate 90° counterclockwise, and send the empty fixture back to the first station; Step 5, second appearance quality inspection: the qualified products in step 4 are flipped by the robot between station 3 and station 4 and moved to the bottom of the camera at station 3, and the pin-fin area and sealing ring area of ​​the heat dissipation substrate are photographed. The image is analyzed by the background program, and the appearance quality of the pin-fin area and sealing ring area of ​​the product is inspected. The inspection information is stored in the database and associated with the product traceability code; an alarm is triggered for unqualified products, and the products are sent to the first conveyor belt by the robot to send the unqualified products out of the inspection system; qualified products are sent to the second conveyor belt for subsequent product packaging.

5. The identification and detection method according to claim 4, characterized in that: The first appearance quality inspection and the second appearance quality inspection are used to judge whether there are unqualified appearance quality conditions including exposed copper, pits, protrusions, and stains on the surface of the pin-fin heat dissipation substrate.

6. The identification and detection method according to claim 4, characterized in that: The warpage detection is to judge whether the warpage caused by the pre-bending process of the pin-fin heat dissipation substrate meets the product requirements.

7. The identification and detection method according to claim 4, characterized in that: In step 3, the unqualified appearance quality of the welding surface in the first appearance quality inspection includes: the presence of exposed copper, or the presence of pits with a diameter greater than 1.5 mm, or the presence of stains with a diameter greater than 0.5 mm, or the presence of protrusions with a height greater than 0.2 mm.

8. The identification and detection method according to claim 4, characterized in that: In step 5, the unqualified appearance quality of the needle wing area in the second appearance quality inspection includes: the presence of exposed copper, or the presence of pits with a diameter greater than 3mm, or the presence of stains with a diameter greater than 0.5mm, or the presence of a bulge on the top of the needle, or the height of the bulge at the root of the needle is greater than 0.5mm.

9. The identification and detection method according to claim 4, characterized in that: In step 5, the unqualified appearance quality of the sealing ring area in the second appearance quality inspection includes: the presence of exposed copper, or the presence of pits, or the presence of stains with a diameter greater than 0.5mm, or the presence of protrusions with a height greater than 0.2mm, or the presence of perceptible scratches.

10. The identification and detection method according to claim 4, characterized in that: The warpage detection in step 4 adopts the method of measuring the height by taking points, with two mutually perpendicular center lines of the heat dissipation substrate as the reference, and two lines parallel to the long side and short side of the heat dissipation substrate are taken respectively with the same distance from the center line. The center point and two endpoints with the same distance from the center point are taken on each line, and the height value of the middle point is subtracted from the average height of the two end points. The warpage value of the long side and short side of the heat dissipation substrate is calculated according to this method.

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