Inspection device and inspection method

Abstract

The invention provides an inspection apparatus and an inspection method, which can easily confirm whether the adjustment of an inspection threshold value is appropriate. The inspection data set indicates position information of a plurality of inspection areas on the substrate, and indicates inspection types and inspection thresholds for each inspection area. The inspection data storage unit stores a plurality of inspection data sets for a plurality of substrate types. The serious defect image storage unit stores a serious defect image associated with each of the plurality of inspection data sets. When one manufacturing lot is inspected, the test inspection control unit acquires, for the substrate type of the manufacturing lot, an adjusted object inspection data set in which the inspection threshold is adjusted. The confirmation inspection control unit applies the adjusted inspection threshold indicated by the inspection data set to be adjusted as a corresponding inspection threshold in the other inspection data set, acquires an applied inspection data set, and causes the inspection unit to execute inspection processing for the severely defective image in the other inspection data set using the applied inspection data set.

Description

[0001] [Cross - reference to related applications]

[0002] This application claims priority from Japanese Patent Application JP2023 - 208367 filed on December 11, 2023, and incorporates the entire disclosure of that application herein. Technical Field

[0003] The present invention relates to a technique for inspecting a substrate. Background Art

[0004] Conventionally, an inspection apparatus has been used that captures an image of a patterned printed substrate and uses the image to detect defects. In addition, in the inspection apparatus disclosed in Japanese Unexamined Patent Application Publication No. 2009 - 210309, a method for easily adjusting (reducing) complex inspection parameters for defect detection is disclosed. On the other hand, when inspecting printed substrates of a manufacturing lot, it is also possible to perform a trial inspection using some of the printed substrates of the manufacturing lot to adjust the inspection threshold. In this case, by inspecting all the printed substrates of the manufacturing lot using the adjusted inspection threshold, false alarms specific to the manufacturing lot can be reduced.

[0005] However, during the process of adjusting the inspection threshold, generally, the inspection threshold is relaxed to reduce false alarms. In this case, it is necessary to confirm whether the adjusted inspection threshold can be used to detect serious defects that must not be missed, that is, it is necessary to confirm whether the adjustment of the inspection threshold is appropriate. It is conceivable to prepare a serious - defect confirmation substrate provided with serious defects and inspect the serious - defect confirmation substrate using the adjusted inspection threshold. However, preparing a serious - defect confirmation substrate requires cost and time, and there is also a problem that the serious - defect confirmation substrate deteriorates over time. Therefore, a method for easily confirming whether the adjustment of the inspection threshold is appropriate is needed. Summary of the Invention

[0006] An object of the present invention is to easily confirm whether the adjustment of the inspection threshold is appropriate.

[0007] A first aspect of the present invention is an inspection apparatus for inspecting a substrate, which includes: an inspection unit that performs an inspection process on a captured image of the substrate using an inspection data set representing position information of a plurality of inspection regions on the substrate and representing the type of inspection and inspection threshold for each inspection region, thereby detecting a defect of the substrate; an inspection data storage unit that stores a plurality of inspection data sets used in the inspection process for a plurality of substrate types; a critical defect image storage unit that stores a plurality of critical defect images respectively associated with any one of the plurality of inspection data sets; an input unit that accepts an input for changing the inspection threshold; a trial inspection control unit that, when inspecting a manufacturing lot, causes the inspection unit to perform the inspection process on a captured image of a partial substrate of the manufacturing lot using an object inspection data set for the substrate type of the manufacturing lot as a trial inspection, and if the input unit has accepted an input for changing the inspection threshold based on the result of the trial inspection, causes the inspection unit to perform a new trial inspection using the object inspection data set with the changed inspection threshold, thereby obtaining an adjusted object inspection data set with the adjusted inspection threshold; and a confirmation inspection control unit that applies the adjusted inspection threshold represented by the adjusted object inspection data set as the inspection threshold corresponding to the adjusted inspection threshold in other inspection data sets for other substrate types, obtains an applied inspection data set, and causes the inspection unit to perform the inspection process on the critical defect image associated with the other inspection data set stored in the critical defect image storage unit using the applied inspection data set as a confirmation inspection.

[0008] According to the present invention, it is possible to easily confirm whether the adjustment of the inspection threshold in the object inspection data set is appropriate.

[0009] A second aspect of the present invention is the inspection apparatus according to the first aspect, wherein the inspection unit performs the inspection process on the captured images of a plurality of substrates included in the manufacturing lot using the adjusted object inspection data set as a mass production inspection.

[0010] A third aspect of the present invention is the inspection apparatus according to the second aspect, wherein if there is a critical defect image not detected by the confirmation inspection, the confirmation inspection control unit does not allow the inspection unit to perform the mass production inspection.

[0011] A fourth aspect of the present invention is the inspection apparatus according to the second aspect (which may also be the second or third aspect), wherein if there is a critical defect image not detected by the confirmation inspection, the confirmation inspection control unit gives the following notice: urging to readjust the adjusted inspection threshold in the adjusted object inspection data set.

[0012] In the fifth mode of the present invention, based on the inspection device of the second mode (which can also be any one of the second to fourth modes), if the input unit has accepted the input of a defect detected by the mass production inspection as a serious defect, the image of the defect is stored in the serious defect image storage unit as a serious defect image in a state associated with the adjusted object inspection data set.

[0013] In the sixth mode of the present invention, based on the inspection device of the first mode (which can also be any one of the first to fifth modes), if the input unit has accepted the input of a defect detected by the test inspection as a serious defect, the image of the defect is stored in the serious defect image storage unit as a serious defect image in a state associated with the object inspection data set.

[0014] In the seventh mode of the present invention, based on the inspection device according to any one of the first to sixth modes, the plurality of inspection data sets are classified into a plurality of groups according to the type of surface treatment and / or the color of the solder resist of the corresponding substrate type, and the other inspection data sets for the confirmation inspection are limited to belong to the same group as the object inspection data set.

[0015] In the eighth mode of the present invention, there is an inspection method for inspecting a substrate using an inspection unit. The inspection unit uses an inspection data set representing the position information of a plurality of inspection regions on the substrate and representing the type of inspection and the inspection threshold for each inspection region to perform an inspection process on the captured image of the substrate, thereby detecting defects of the substrate. The inspection method includes: a) a process of preparing a plurality of inspection data sets respectively used in the inspection processes for a plurality of substrate types; b) a process of preparing a plurality of serious defect images respectively associated with any one of the plurality of inspection data sets; c) a process of, when inspecting a manufacturing lot, causing the inspection unit to perform the inspection process on the captured images of some substrates of the manufacturing lot using the object inspection data set for the substrate type of the manufacturing lot as a test inspection; d) a process of, if the inspection threshold of the object inspection data set is changed according to the result of the test inspection, causing the inspection unit to perform a new test inspection using the object inspection data set with the changed inspection threshold, thereby obtaining an adjusted object inspection data set with the adjusted inspection threshold; e) a process of applying the adjusted inspection threshold represented by the adjusted object inspection data set as the inspection threshold corresponding to the adjusted inspection threshold in other inspection data sets for other substrate types, thereby obtaining an applied inspection data set; and f) a process of causing the inspection unit to perform the inspection process on the serious defect images associated with the other inspection data sets using the applied inspection data set as a confirmation inspection.

[0016] The above objects and other objects, features, aspects and advantages will become more apparent from the following detailed description of the present invention with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a block diagram showing the structure of the inspection device.

[0018] Figure 2 It is a diagram showing the structure of a computer.

[0019] Figure 3A It is a diagram showing a plurality of inspection areas on a printed circuit board of substrate type A.

[0020] Figure 3B It is a diagram showing a plurality of inspection areas on a printed circuit board of substrate type B.

[0021] Figure 3C It is a diagram showing a plurality of inspection areas on a printed circuit board of substrate type C.

[0022] Figure 4 It is a diagram showing a plurality of serious defect images stored in the serious defect image storage unit.

[0023] Figure 5A It is a diagram showing the inspection process of a printed circuit board performed by the inspection device.

[0024] Figure 5B It is a diagram showing the inspection process of a printed circuit board performed by the inspection device.

[0025] Figure 6 It is a diagram showing a plurality of inspection areas on a printed circuit board of substrate type D.

[0026] Figure 7 It is a diagram showing the grouped inspection data set. DESCRIPTION OF THE REFERENCE NUMERALS

[0027] 1 Inspection device

[0028] 9 Printed circuit board

[0029] 23 Main body inspection unit

[0030] 36 Input unit

[0031] 41 Test inspection control unit

[0032] 42 Confirmation inspection control unit

[0033] 43 Auxiliary inspection unit

[0034] 44 Inspection data storage unit

[0035] 44a, 44b Groups

[0036] 45 Serious defect image storage unit

[0037] 92 Inspection area

[0038] 441 Inspection data set

[0039] 451 Serious defect image

[0040] Steps S10 to S26 Detailed implementation manner

[0041] Figure 1 FIG. is a block diagram showing the structure of an inspection apparatus 1 according to an embodiment of the present invention. The inspection apparatus 1 is an apparatus for inspecting a printed circuit board, and in one example, it is used for the final appearance inspection of the printed circuit board. The inspection apparatus 1 can also be used for inspections other than the final appearance inspection. The inspection apparatus 1 includes a device main body 2 and an auxiliary unit 4. The device main body 2 and the auxiliary unit 4 are communicably connected via a network 8 such as a LAN (Local Area Network) or the Internet.

[0042] The device main body 2 includes an imaging unit 21, a moving mechanism 22, a main body inspection unit 23, and a main body control unit 24. The imaging unit 21 has an imaging element such as a CCD (Charge Coupled Device) sensor or a CMOS (Complementary Metal Oxide Semiconductor) sensor, and images the printed circuit board. In this processing example, the captured image obtained by the imaging unit 21 is a color image. The captured image can also be a grayscale image. The moving mechanism 22 has, for example, a motor, a ball screw, etc., and relatively moves the printed circuit board with respect to the imaging unit 21. The main body inspection unit 23 performs an inspection process on the captured image output from the imaging unit 21 using the inspection data set 441 described later, and detects defects from the captured image. The main body control unit 24 is responsible for the overall control of the device main body 2. The main body inspection unit 23 and the main body control unit 24 are implemented by, for example, a computer and / or a circuit.

[0043] The auxiliary unit 4 is implemented by a computer. Figure 2This is a diagram showing the structure of computer 3. Computer 3 has the structure of a general computer system, which includes a CPU (Central Processing Unit), a central processor 31, a ROM (Read-Only Memory) 32, a RAM (Random Access Memory) 33, a storage device 34, a display unit (display) 35, an input unit 36, a reading device 37, a communication unit 38, a GPU (Graphics Processing Unit) 39, and a bus 30. The CPU 31 performs various arithmetic processes. The GPU 39 performs various arithmetic processes related to image processing and the like. The ROM 32 stores basic programs. The RAM 33 and the storage device 34 store various information. The display unit 35 displays various information such as images. The input unit 36 has a keyboard 36a and a mouse 36b that accept input from an operator. The reading device 37 reads information from a computer-readable recording medium 81 such as an optical disc, a magnetic disk, a magneto-optical disc, a memory card, etc. The communication unit 38 transmits and receives signals to and from the device main body 2 and the like. The bus 30 is a signal circuit that connects the CPU 31, the GPU 39, the ROM 32, the RAM 33, the storage device 34, the display unit 35, the input unit 36, the reading device 37, and the communication unit 38. In computer 3, a touch panel can be provided, and the input unit 36 and the display unit 35 can be realized through this touch panel.

[0044] In computer 3, the program 811 is read out from the recording medium 81 in advance via the reading device 37 and stored in the storage device 34. The program 811 can be stored in the storage device 34 via the network 8. The CPU 31 and the GPU 39 execute arithmetic processes while using the RAM 33 or the storage device 34 according to the program 811. The CPU 31 and the GPU 39 function as arithmetic units in computer 3. In addition to the CPU 31 and the GPU 39, other structures can also be used as arithmetic units to function.

[0045] In the auxiliary unit 4, computer 3 executes arithmetic processes and the like according to the program 811, whereby the Figure 1 function structure shown can be realized. That is, the CPU 31, the GPU 39, the ROM 32, the RAM 33, the storage device 34 of computer 3, and their peripheral structures realize the auxiliary unit 4. All or part of the functions of the auxiliary unit 4 can be realized by dedicated circuits, and each function can also be realized by separate programs. In addition, the auxiliary unit 4 can also be realized by using a plurality of computers. In this processing example, the auxiliary inspection unit 43 described later includes a dedicated image processing circuit (image processing board).

[0046] The auxiliary unit 4 includes a test inspection control section 41, a confirmation inspection control section 42, an auxiliary inspection section 43, an inspection data storage section 44, a serious defect image storage section 45, a display section 35, and an input section 36. Similar to the main inspection section 23, the auxiliary inspection section 43 performs an inspection process on a captured image representing a printed circuit board using an inspection data set 441, and detects defects from the captured image. The test inspection control section 41 controls the auxiliary inspection section 43 to perform a test inspection described later. The confirmation inspection control section 42 controls the auxiliary inspection section 43 to perform a confirmation inspection described later. The test inspection control section 41 and the confirmation inspection control section 42 are part of the unit control section 40, and the unit control section 40 is also responsible for the overall control of the auxiliary unit 4. The inspection data storage section 44 stores a plurality of inspection data sets 441 used in the inspection process. The serious defect image storage section 45 stores a plurality of serious defect images (data) 451 used in the confirmation inspection.

[0047] Figures 3A to 3C It is a diagram for explaining the inspection data set 441, showing a plurality of inspection regions 92 on the printed circuit board 9. Figure 3A It represents the printed circuit board 9 of substrate type A. Figure 3B It represents the printed circuit board 9 of substrate type B. Figure 3C It represents the printed circuit board 9 of substrate type C. The substrate type is the type of printed circuit board product, and for example, it is distinguished by a product number. Each inspection data set 441 represents the position information (including the size of the inspection region 92) of a plurality of inspection regions 92 on the printed circuit board 9, and represents the type of inspection and the inspection threshold for each inspection region 92. The plurality of inspection data sets 441 are respectively used in the inspection processes for printed circuit boards 9 with different substrate types. As Figures 3A to 3C shown, in the printed circuit board 9, the substrate size, the position and size of the inspection region 92, etc. vary depending on the substrate type.

[0048] Each inspection region 92 belongs to any one of a plurality of region categories. As the plurality of region categories, examples can be given such as a pad region where a metal such as copper is exposed, a solder resist region (hereinafter, also referred to as an "SR region") where the substrate of the printed circuit board 9 is the base material under the solder resist, a wiring region where wiring is provided under the solder resist, a screen region such as characters or marks printed on the solder resist, a via hole region that is the opening of a through hole, etc.

[0049] In each inspection area 92, the type corresponding to the area category is inspected. In the inspection area 92 where the area category is a pad area, for example, the minimum distance of the area between two adjacent pads is obtained. If the minimum distance is less than the inspection threshold, an inspection is performed to detect this area as a defect. In the inspection area 92 where the area category is an SR area, for example, the gray-scale value of each position is obtained for each color component, and an inspection is performed to detect the set of positions where the gray-scale value deviates from the normal range defined by the inspection threshold (upper limit value and lower limit value) as a defect. In the inspection area 92 where the area category is a via hole area, for example, the minimum width of the land around the via hole is obtained. If the minimum width is less than the inspection threshold, an inspection is performed to detect this land as a defect. In practice, various well-known inspections can be performed according to each area category.

[0050] As described above, the inspection data set 441 represents the position information of each inspection area 92, as well as the type and inspection threshold of the inspection for the inspection area 92. The values of various parameters in each inspection (for example, the size of the mask area when a mask area is set, etc.) can also be included in the inspection data set 441. In the following description, it is assumed that the inspection data sets 441 of substrate types A to C are stored in the inspection data storage unit 44. Among these substrate types A to C, the design rules and the like are the same. Of course, the inspection data sets 441 of two substrate types or four or more substrate types can also be stored. In addition, in the following description, it is assumed that each inspection area 92 belongs to any one of the first area category, the second area category, and the third area category. The inspection data sets 441 of each substrate type A to C include at least one inspection area 92 of the first area category, at least one inspection area 92 of the second area category, and at least one inspection area 92 of the third area category. The inspection data set 441 can also represent the position information of the inspection areas 92 on the two main surfaces of the printed circuit board 9.

[0051] Figure 4 It is a diagram showing a plurality of serious defect images 451 stored in the serious defect image storage unit 45. Each serious defect image 451 is associated with any one of the plurality of inspection data sets 441. In Figure 4In the example, a serious defect image 451 associated with the inspection data set 441 of substrate type A is surrounded by a dotted rectangle marked with reference numeral A, a serious defect image 451 associated with the inspection data set 441 of substrate type B is surrounded by a dotted rectangle marked with reference numeral B, and a serious defect image 451 associated with the inspection data set 441 of substrate type C is surrounded by a dotted rectangle marked with reference numeral C. Each serious defect image 451 associated with the inspection data set 441 of substrate type A is detected by performing an inspection process on the printed substrate 9 of substrate type A using the inspection data set 441. In fact, the inspection area 92 where the serious defect image 451 is detected is also determined. The same is true for the serious defect image 451 associated with the inspection data set 441 of substrate type B and the serious defect image 451 associated with the inspection data set 441 of substrate type C.

[0052] However, usually, the printed circuit board 9 is manufactured in units of manufacturing batches. A manufacturing batch is a collection of multiple printed circuit boards 9 of the same substrate type manufactured under the same conditions. One manufacturing batch includes, for example, 1,000 printed circuit boards 9. In the manufacturing process of the printed circuit board 9, due to the deviation of materials between batches, the influence of temperature or humidity, etc., each manufacturing batch will produce unique changes. For example, sometimes due to the deviation of solder resist or screen ink, the color of the SR area or the screen area will change with each manufacturing batch. In addition, due to the influence of temperature and humidity when the solder resist layer is formed, the size of the exposed pad will sometimes change with each manufacturing batch. In this way, in the case of unique changes in each manufacturing batch, even if the same inspection area 92 is inspected in the same type using the same inspection threshold, there is a possibility of increasing false alarms (detection of pseudo defects) due to different manufacturing batches. Therefore, it is preferred to adjust the inspection threshold according to the unique changes of each manufacturing batch. The following describes the process of adjusting the inspection threshold according to the manufacturing batch and inspecting the printed circuit board 9.

[0053] Figure 5A and 5B 4 is a diagram showing the inspection process of the printed circuit board 9 performed by the inspection device 1. Here, the process of inspecting the printed circuit boards 9 included in the initial manufacturing lot of a new substrate type D for which the inspection data set 441 has not yet been prepared (hereinafter referred to as the "target manufacturing lot") is described.

[0054] During the inspection process of the printed circuit board 9, a plurality of inspection data sets 441 used in the inspection processes for a plurality of board types are stored in advance in the inspection data storage unit 44 in preparation (step S10). Here, the inspection data set 441 for board type A, the inspection data set 441 for board type B, and the inspection data set 441 for board type C are stored in the inspection data storage unit 44.

[0055] In addition, in Figure 4 the severe defect image storage unit 45 shown, the severe defect images 451 associated with the inspection data set 441 for board type A, the severe defect images 451 associated with the inspection data set 441 for board type B, and the severe defect images 451 associated with the inspection data set 441 for board type C are stored in preparation (step S11). The severe defect image 451 corresponding to board type A is an image determined to be a true defect by an operator during the inspection of the manufacturing lot of board type A before the inspection of the target manufacturing lot. Similarly, the severe defect image 451 corresponding to board type B is an image determined to be a true defect by an operator during the inspection of the manufacturing lot of board type B, and the severe defect image 451 corresponding to board type C is an image determined to be a true defect by an operator during the inspection of the manufacturing lot of board type C.

[0056] In Figure 1 the inspection apparatus 1, a part of the printed circuit boards 9 (for example, 20 to 30 printed circuit boards 9) included in the target manufacturing lot are carried into the apparatus main body 2, and a plurality of captured images representing this part of the printed circuit boards 9 are acquired by the imaging unit 21. Although each captured image in this processing example is an image representing the whole (the whole of both sides or one side) of the printed circuit board 9, it can also be an image representing a part of the printed circuit board 9. As will be described later, since these plurality of captured images are respectively used for trial inspections, they are hereinafter referred to as "trial inspection images". The plurality of trial inspection images are sent from the apparatus main body 2 to the auxiliary unit 4 via the network 8 and are stored in an inspection image storage unit (not shown).

[0057] Next, the control of the control unit 41 is checked through experiments. In the auxiliary inspection unit 43, inspection processing of a plurality of test inspection images is performed as a test inspection (step S12). During the test inspection, an inspection data set for the substrate type D of the target manufacturing lot (hereinafter referred to as the "target inspection data set") is used. In this processing example, the target manufacturing lot is the first manufacturing lot of the substrate type D, and there is currently no inspection data set for the substrate type D (that is, the target inspection data set). For example, the operator designates a plurality of inspection regions 92 on the printed circuit board 9 using the input unit 36, determines the region categories of the respective inspection regions 92, and thus creates the target inspection data set. At this time, the types of inspections for each region category have been previously determined. In addition, for each region category, an inspection threshold for detecting a serious defect image 451 as a defect is also prepared in advance as an inspection threshold scheme. The created target inspection data set is stored in the inspection data storage unit 44.

[0058] Figure 6 It is a diagram showing a plurality of inspection regions 92 on the printed circuit board 9 represented by the target inspection data set for the substrate type D. The target inspection data set includes at least one inspection region 92 of the first region category, at least one inspection region 92 of the second region category, and at least one inspection region 92 of the third region category. The test inspection control unit 41 may also automatically create the target inspection data set by determining the region categories of the respective regions of the test inspection image according to a prescribed algorithm. When creating the target inspection data set, an image obtained by averaging a plurality of captured images may be used as the main image.

[0059] During the test inspection of a plurality of test inspection images using the target inspection data set, inspections of the types corresponding to the region categories of the respective inspection regions 92 (corresponding regions) in the test inspection images are performed, and defects are detected based on the inspection thresholds. For example, if the inspection region 92 is a pad region, the minimum distance between the pads is compared with the inspection threshold. In this way, in the inspection region 92 of the first region category, the inspection for the first region category is performed using the inspection threshold of the first region category. Similarly, in the inspection region 92 of the second region category, the inspection for the second region category is performed using the inspection threshold of the second region category, and in the inspection region 92 of the third region category, the inspection for the third region category is performed using the inspection threshold of the third region category.

[0060] If the test inspection is completed, the result of the test inspection is displayed on the display unit 35 (step S13). The result of the test inspection includes, for example, an image of a defect detected by the test inspection. An area in the main image representing the same range as the detected defect may be displayed together with the image of the defect. Preferably, the image of the defect is displayed in a state where the area category can be determined, or the image of the defect may be displayed separately by area category. As a result of the test inspection, the number of defects detected for each area category may also be displayed.

[0061] The result of the test inspection displayed on the display unit 35 is confirmed by the operator. If there is a defect among the defects displayed on the display unit 35 that the operator determines to be a true defect, the operator performs an input indicating that the defect is a true defect through the input unit 36 (step S14). For example, by the operator selecting the defect on the display unit 35 and clicking the right button of the mouse 36b and selecting the registration of a true defect from the displayed menu, the defect can be easily registered as a true defect. In this way, if the input unit 36 has accepted the input of setting a defect as a true defect, the image of the defect (true defect) is stored in the serious defect image storage unit 45 as a new serious defect image 451 by the test inspection control unit 41 (step S15). The object inspection data set (that is, the inspection data set of the substrate type D) and the detected inspection area 92 are associated with the serious defect image 451. If there is no defect determined by the operator to be a true defect, the above input is not performed (step S14).

[0062] In addition, if the operator determines that it is necessary to change the inspection threshold based on the result of the test inspection, the operator changes the inspection threshold using the input unit 36 (step S16). For example, if many defects displayed on the display unit 35 exist in the inspection area 92 of the first area category and are false alarms, the inspection threshold is changed to relax the inspection criterion for the inspection area 92 of the first area category (that is, the range determined to be normal is expanded). In the example where the inspection area 92 is a pad area, the inspection threshold for the minimum distance between pads is decreased. For the inspection area 92 of the second area category and the inspection area 92 of the third area category, if there are many false alarms, the inspection threshold is changed in the same way. If the input unit 36 has accepted the input of changing the inspection threshold, the inspection process of a plurality of test inspection images using the object inspection data set with the changed inspection threshold is performed as a new test inspection, and the result of the test inspection is displayed on the display unit 35 (steps S12, S13).

[0063] If there are defects in the results of the test inspection that the operator determines to be true defects, then, similarly to the above, the images of these defects are stored as new serious defect images 451 in the serious defect image storage unit 45 (steps S14, S15). Additionally, if the operator determines that the inspection threshold needs to be changed again because false alarms are not sufficiently reduced in the results of the test inspection, etc., then the inspection threshold is further changed (step S16). Then, a new test inspection using the object inspection data set with the changed inspection threshold is further performed, and the results of this test inspection are displayed on the display unit 35 (steps S12, S13). Changing the inspection threshold and repeating the new test inspection, etc., are repeated until the operator determines that the inspection threshold does not need to be changed (steps S12 to S16). Thus, an adjusted object inspection data set with the adjusted inspection threshold is obtained to be able to reduce false alarms. In fact, an input indicating that the inspection threshold does not need to be changed is received by the input unit 36, and the object inspection data set at this time is the adjusted object inspection data set. Hereinafter, the inspection threshold represented by the adjusted object inspection data set is referred to as the "adjusted inspection threshold".

[0064] If the adjusted object inspection data set for substrate type D is obtained, then in the confirmation inspection control unit 42, the adjusted inspection threshold represented by the adjusted object inspection data set is applied as the inspection threshold corresponding to the adjusted inspection threshold in the other inspection data sets 441 for the other substrate types A to C. For example, the inspection threshold for the inspection area 92 of the first region category in the inspection data set 441 for substrate type A is converted to the adjusted inspection threshold of the first region category in the adjusted object inspection data set. Similarly, the inspection threshold for the inspection area 92 of the second region category is converted to the adjusted inspection threshold of the second region category, and the inspection threshold for the inspection area 92 of the third region category is converted to the adjusted inspection threshold of the third region category. Thus, the applied inspection data set for substrate type A is obtained (step S17). Similarly, the applied inspection data set for substrate type B and the applied inspection data set for substrate type C are obtained.

[0065] If the applied inspection data sets for substrate types A to C are obtained, then an inspection process using the applied inspection data sets for serious defect images 451 associated with the other inspection data sets 441 other than the object inspection data set is performed as the confirmation inspection (step S18). For example, for Figure 4Each severe defect image 451 of the substrate type A shown is inspected using the applied inspection dataset of the substrate type A. At this time, if the severe defect image 451 is associated with the inspection area 92 of the first area category, for example, the severe defect image 451 is inspected for the first area category, and it is determined whether it is a defect using the adjusted inspection threshold of the first area category. For the severe defect image 451 associated with the inspection area 92 of the second area category, the second area category inspection is performed using the adjusted inspection threshold of the second area category. For the severe defect image 451 associated with the inspection area 92 of the third area category, the third area category inspection is performed using the adjusted inspection threshold of the third area category. Similarly, for each severe defect image 451 of the substrate type B, the inspection process is performed using the applied inspection dataset of the substrate type B, and for each severe defect image 451 of the substrate type C, the inspection process is performed using the applied inspection dataset of the substrate type C.

[0066] When it is confirmed that the inspection is completed, the result of the confirmation inspection is displayed on the display unit 35 (step S19). For example, the severe defect images 451 that are not detected as defects among the plurality of severe defect images 451 after the confirmation inspection (hereinafter, referred to as "undetected severe defect images 451") are displayed on the display unit 35. The undetected severe defect images 451 are preferably displayed in a state where their area category (that is, the area category of the inspection area 92 associated with the severe defect image 451) can be determined. All the severe defect images 451 can be arranged and displayed, and the undetected severe defect images 451 can be emphasized by surrounding them with a thick line, etc. If there are undetected severe defect images 451 (step S20), the confirmation inspection control unit 42 issues the following notification: urging the re-adjustment of the adjusted inspection threshold (step S21). In one example, a message urging the re-adjustment of the adjusted inspection threshold is displayed on the display unit 35. The following notification can also be made by sound, etc.: urging the re-adjustment of the adjusted inspection threshold.

[0067] When the notification for urging the re-adjustment of the adjusted inspection threshold is issued, the operator changes the adjusted inspection threshold in the adjusted object inspection dataset using the input unit 36 (step S22). That is, the input unit 36 accepts the input of the change of the adjusted inspection threshold. For example, the adjusted inspection threshold is changed so that the inspection standard for the inspection area 92 of the area category of the undetected severe defect image 451 becomes stricter (that is, the range determined to be normal is narrowed).

[0068] If the adjusted inspection threshold in the adjusted object inspection dataset is changed to a new adjusted inspection threshold, then this new adjusted inspection threshold is applied as the inspection threshold corresponding to this adjusted inspection threshold in the applied inspection datasets for substrate types A to C. That is, in the applied inspection datasets for substrate types A to C, the inspection threshold for the inspection area 92 of each area category is converted to the new adjusted inspection threshold of this area category in the adjusted object inspection dataset. Then, an inspection process for the severe defect image 451 using the new applied inspection dataset is performed as a new confirmation inspection (step S18), and the result of the confirmation inspection is displayed on the display unit 35 (step S19).

[0069] The change of the adjusted inspection threshold and the execution of the confirmation inspection using the new applied inspection dataset are repeated until there are no undetected severe defect images 451 in the result of the confirmation inspection (steps S18 to S22). Thus, an adjusted object inspection dataset capable of detecting all the severe defect images 451 after the confirmation inspection as defects is obtained. This adjusted object inspection dataset becomes the inspection dataset for mass production inspection for the target manufacturing lot described later, and the object inspection dataset in the inspection data storage unit 44 is updated to this inspection dataset.

[0070] On the other hand, if there are no undetected severe defect images 451 in the result of the initial confirmation inspection (step S20), the adjusted inspection threshold is not readjusted, and the adjusted object inspection dataset directly becomes the inspection dataset for mass production inspection for the target manufacturing lot. As described above, the inspection dataset for mass production inspection for the target manufacturing lot is obtained only when there are no undetected severe defect images 451 in the confirmation inspection. In other words, if there are undetected severe defect images 451 in the confirmation inspection, the confirmation inspection control unit 42 does not allow the execution of mass production inspection, and if there are no undetected severe defect images 451 in the confirmation inspection, the confirmation inspection control unit 42 allows the execution of mass production inspection.

[0071] The inspection dataset for mass production inspection is sent to Figure 1 the device main body 2 and stored in the main body inspection unit 23. In the device main body 2, a plurality of captured images representing a plurality of printed circuit boards 9 included in the target manufacturing lot are sequentially obtained by the imaging unit 21. In the main body inspection unit 23, an inspection process is performed on the plurality of captured images as mass production inspection (step S23). During the mass production inspection, the inspection dataset for mass production inspection is used. Preferably, the mass production inspection is partially performed in parallel with the acquisition of the plurality of captured images. In addition, for the printed circuit board 9 that has obtained the test inspection image among the plurality of printed circuit boards 9 included in the target manufacturing lot, the test inspection image can be directly used for mass production inspection.

[0072] The results of mass production inspection are sent to the auxiliary unit 4 and displayed on the display unit 35 (step S24). The results of mass production inspection include, for example, images of defects detected through mass production inspection. The area in the main image representing the same range as the detected defect can be displayed together with the image of the defect. The operator confirms the results of mass production inspection displayed on the display unit 35. If there is a defect among the defects displayed on the display unit 35 that the operator determines to be a true defect, then, similarly to step S14, the operator uses the input unit 36 to input that the defect is a true defect (step S25). Thereby, the image of this defect is stored as a new serious defect image 451 in the serious defect image storage unit 45 (step S26). The inspection data set and the detected inspection area 92 are associated with the serious defect image 451. If there is no defect that the operator determines to be a true defect, the above input is not performed (step S25). When the inspection process for the captured images of all the printed circuit boards 9 included in the target manufacturing lot is completed, the inspection of the printed circuit boards 9 performed by the inspection device 1 is completed.

[0073] In the inspection device 1, steps S24 to S26 are omitted Figure 5B and the information of the defects detected through mass production inspection can be output to an external defect confirmation device, for example. The information of the defects includes, for example, the image of the defect, the identification information of the printed circuit board 9 including the defect, and the position information of the defect on the printed circuit board 9, etc. In the defect confirmation device, the area of the defect on the printed circuit board 9 is photographed with reference to the information of the defect and displayed on the display unit. The operator determines whether the defect is a true defect or a false alarm by confirming the defect included in the displayed image.

[0074] In the above processing example, since the first manufacturing lot of the new substrate type D is the inspection target, during the confirmation inspection, there are almost no serious defect images 451 of substrate type D, and the inspection process for the serious defect images 451 of other substrate types A to C is performed. On the other hand, if the inspection data set 441 for the substrate type of the target manufacturing lot has been created and there are serious defect images 451 of this substrate type, then during the confirmation inspection, in addition to the inspection process for the serious defect images 451 of other substrate types, the inspection process for the serious defect images 451 of this substrate type can also be performed.

[0075] In Figure 1 the inspection device 1, the device main body 2 and the auxiliary unit 4 are respectively provided. For example, the structure of the auxiliary unit 4 can be implemented by the computer possessed by the device main body 2. In this case, the main body inspection unit 23 and the auxiliary inspection unit 43 are implemented by one inspection unit. In other words, in the case where the device main body 2 and the auxiliary unit 4 are respectively provided Figure 1In the inspection device 1, it can be said that the inspection unit has a first inspection unit (auxiliary inspection unit 43) that performs trial inspection and confirmation inspection, and a second inspection unit (main body inspection unit 23) that performs mass production inspection.

[0076] As in the above example, if the device main body 2 and the auxiliary unit 4 are provided separately, the device main body 2 includes a photographing unit 21 and a second inspection unit, and the auxiliary unit 4 includes a trial inspection control unit 41, a confirmation inspection control unit 42, a first inspection unit, an inspection data storage unit 44, and a serious defect image storage unit 45. Then, it is possible to perform photographing (acquisition of a photographed image for mass production inspection) of a plurality of printed circuit boards 9 in the device main body 2 in parallel with the processing of the above steps S12 to S22 in the auxiliary unit 4. As a result, the operation rate of the device main body 2 is improved, and the inspection efficiency of the printed circuit board 9 is improved.

[0077] As described above, Figure 1 The inspection unit of the inspection device 1 uses an inspection data set 441 that represents the position information of a plurality of inspection regions 92 on the printed circuit board 9 and represents the type of inspection and the inspection threshold for each inspection region 92, and performs an inspection process on the photographed image of the printed circuit board 9, thereby detecting defects of the printed circuit board 9. The inspection data storage unit 44 stores a plurality of inspection data sets 441 used in the inspection processes for a plurality of substrate types. When inspecting one manufacturing lot, the trial inspection control unit 41 causes the inspection unit ( Figure 1 in this case, the auxiliary inspection unit 43) to perform an inspection process on the photographed image of a part of the printed circuit boards 9 of the manufacturing lot using the target inspection data set for the substrate type of the manufacturing lot as a trial inspection. In addition, if the input unit 36 has received an input for changing the inspection threshold based on the result of the trial inspection, the inspection unit is caused to perform a new trial inspection using the target inspection data set in which the inspection threshold has been changed. Thus, in the inspection device 1, by adjusting the inspection threshold according to the result of the trial inspection, it is possible to suppress an increase in false alarms caused by unique variations generated in each manufacturing lot.

[0078] In addition, the serious defect image storage unit 45 stores a plurality of serious defect images 451 respectively associated with any one of the plurality of inspection data sets 441. The confirmation inspection control unit 42 applies the adjusted inspection threshold represented by the above adjusted target inspection data set as the inspection threshold corresponding to the adjusted inspection threshold in other inspection data sets 441 for other substrate types, and obtains an applied inspection data set. Then, the inspection unit ( Figure 1In this case, the auxiliary inspection unit 43) performs an inspection process on the serious defect image 451 associated with the other inspection data set 441 stored in the serious defect image storage unit 45 using the applied inspection data set as a confirmation inspection. Thus, in the inspection apparatus 1, it is possible to easily confirm whether serious defects can be detected using the adjusted inspection threshold in the object inspection data set, that is, it is possible to easily confirm whether the adjustment of the inspection threshold is appropriate. In addition, since there is no need to prepare a substrate for serious defect confirmation, it is possible to reduce the production cost and management cost of the substrate for serious defect confirmation, etc.

[0079] Preferably, in the inspection unit ( Figure 1 In this case, the main inspection unit 23) performs an inspection process on the captured images of the plurality of printed circuit boards 9 included in the manufacturing lot using the above-mentioned adjusted object inspection data set as a mass production inspection. By using the adjusted object inspection data set that has been confirmed to detect serious defects through the confirmation inspection for the mass production inspection, it is possible to reduce false alarms and detect serious defects during the mass production inspection.

[0080] Preferably, if there is a serious defect image that has not been detected through the confirmation inspection, the confirmation inspection control unit 42 does not allow the inspection unit to perform the mass production inspection. Thus, it is possible to prevent the omission of serious defects from occurring during the mass production inspection using an inappropriate adjusted object inspection data set.

[0081] Preferably, if there is a serious defect image that has not been detected through the confirmation inspection, the confirmation inspection control unit 42 issues the following notification: urging the re-adjustment of the adjusted inspection threshold in the adjusted object inspection data set. Thus, it is possible to obtain an adjusted object inspection data set that can detect serious defects and reduce false alarms, and it is possible to more reliably achieve an appropriate mass production inspection.

[0082] Preferably, if the input unit 36 has accepted the input of a defect detected through the trial inspection as a true defect, the image of the defect is stored in the serious defect image storage unit 45 as the serious defect image 451 in a state associated with the object inspection data set. Similarly, if the input unit 36 has accepted the input of a defect detected through the mass production inspection as a true defect, the image of the defect is stored in the serious defect image storage unit 45 as the serious defect image 451 in a state associated with the adjusted object inspection data set. In either case, it is possible to easily prepare an appropriate serious defect image 451 for the operator to confirm.

[0083] In the above processing example, among a plurality of substrate types corresponding to a plurality of inspection data sets 441, the types of surface treatment (copper flux, gold, solder, tin, etc.) of the pad regions and the colors of the solder masks (green, black, blue, white, etc.) are the same. Therefore, the severe defect images 451 of all inspection data sets 441 other than the target inspection data set can be used for confirmation inspection. On the other hand, if a substrate type in which at least one of the type of surface treatment of the pad region and the color of the solder mask is different from those of other substrate types is mixed in the plurality of substrate types, preferably, the severe defect images 451 used for confirmation inspection are restricted according to the substrate type of the target inspection data set.

[0084] In Figure 7 the example of, a plurality of inspection data sets 441 for a plurality of substrate types A to D are divided into a first group 44a and a second group 44b. The first group 44a includes the inspection data sets 441 of substrate types A and C (in Figure 7 it, denoted as "inspection data set A" and "inspection data set C"). In substrate types A and C, the types of surface treatment and the colors of the solder masks are the same as each other. The second group 44b includes the inspection data sets 441 of substrate types B and D (in Figure 7 it, denoted as "inspection data set B" and "inspection data set D"). In substrate types B and D, the types of surface treatment and the colors of the solder masks are the same as each other, but are different from those of substrate types A and C.

[0085] For example, if the inspection data set 441 of substrate type D is the target inspection data set, then in Figure 5A step S17 of, the applied inspection data set is obtained only from other inspection data sets 441 belonging to the same second group 44b as the target inspection data set, that is, the inspection data set 441 of substrate type B. In other words, the applied inspection data set is not obtained from the inspection data sets 441 of substrate types A and C belonging to the first group 44a. Then, an inspection process using the applied inspection data set of substrate type B for the severe defect image 451 of substrate type B is performed as a confirmation inspection (step S18). In step S18, the severe defect images 451 of substrate types A and C are not subjected to confirmation inspection. The following processing is the same as the above processing.

[0086] As described above, in this processing example, a plurality of inspection data sets 441 are classified into a plurality of groups 44a and 44b according to the types of surface treatment and the colors of solder masks corresponding to the substrate types. Moreover, the inspection data sets 441 for confirmation inspection are restricted to belong to the same group as the object inspection data set. Thus, only the severe defect images 451 of the inspection data sets 441 belonging to the same group as the object inspection data set are used in the confirmation inspection. As a result, it is possible to prevent the differences in the types of surface treatment and the colors of solder masks from affecting the results of the confirmation inspection, and it is possible to appropriately confirm whether the adjustment of the inspection threshold in the object inspection data set is appropriate. In addition, depending on the type of inspection used in the inspection apparatus 1 or the like, it is also possible to focus only on either the type of surface treatment or the color of the solder mask corresponding to the substrate type, and classify the plurality of inspection data sets 441 into a plurality of groups. The number of groups may also be three or more.

[0087] Various modifications can be made to the above-described inspection apparatus 1 and inspection method.

[0088] In the above-described embodiment, although all the images determined by the operator to be true defects are processed as severe defect images, for example, the operator may also select images with a higher degree of importance among the true defects and store them as severe defect images in the severe defect image storage unit 45. As described above, if the input unit 36 has received an input of a defect detected in the trial inspection or mass production inspection as a severe defect, the image of the defect may also be stored as a severe defect image 451 in the severe defect image storage unit 45. The severe defect images 451 can also be obtained other than in the trial inspection and mass production inspection.

[0089] If there are severe defect images that have not been detected by the confirmation inspection, the operator can determine whether the mass production inspection can be performed by the inspection unit. In addition, a notification urging readjustment of the adjusted inspection threshold can also be made according to other conditions such as the case where a specific severe defect image has not been detected.

[0090] The object to be inspected in the inspection apparatus 1 may be a substrate such as a semiconductor substrate or a glass substrate in addition to the printed circuit board 9.

[0091] The structures in the above-described embodiment and each modification can be appropriately combined as long as they do not contradict each other.

[0092] Although the invention has been described and explained in detail, the above description is exemplary and not restrictive. Therefore, it can be said that there are various modifications and ways as long as the scope of the present invention is not departed from.

Claims

1. An inspection device for inspecting a substrate, wherein: The inspection device comprises: An inspection unit that performs inspection processing on a captured image of the substrate using an inspection data set that indicates position information of a plurality of inspection areas on the substrate and indicates a type of inspection and an inspection threshold for each inspection area, thereby detecting defects of the substrate; An inspection data storage unit storing a plurality of inspection data sets respectively used in the inspection process for a plurality of substrate types; A severe defect image storage unit, storing a plurality of severe defect images respectively associated with any one of the plurality of inspection data sets; An input unit that receives an input of a change in the inspection threshold; a test inspection control section, which, when inspecting a manufacturing lot, causes the inspection section to execute the inspection process performed on the captured images of some substrates of the manufacturing lot using the object inspection data set for the substrate type of the manufacturing lot as a test inspection, and, if the input section has accepted an input of a change of the inspection threshold value based on a result of the test inspection, causes the inspection section to execute a new test inspection using the object inspection data set after the inspection threshold value has been changed, thereby acquiring an adjusted object inspection data set after the inspection threshold value has been adjusted; as well as A confirmation inspection control unit applies the adjusted inspection threshold represented by the adjusted object inspection data set as the inspection threshold corresponding to the adjusted inspection threshold in other inspection data sets for other substrate types, obtains the applied inspection data set, and enables the inspection unit to perform the inspection processing using the applied inspection data set on the severe defect image associated with the other inspection data set stored in the severe defect image storage unit as a confirmation inspection.

2. The inspection device according to claim 1, wherein: The inspection section performs the inspection process on captured images of a plurality of substrates included in the manufacturing lot using the adjusted object inspection data set as a mass production inspection.

3. The inspection device according to claim 2, wherein: The confirmation inspection control section does not allow the inspection section to perform the mass production inspection if there is a serious defective image that is not detected by the confirmation inspection.

4. The inspection device according to claim 2, wherein: If there is a serious defect image that has not been detected by the confirmation inspection, the confirmation inspection control section makes a notification to urge re-adjustment of the adjusted inspection threshold in the adjusted object inspection data set.

5. The inspection device according to claim 2, wherein: If the input unit has accepted an input of a defect detected by the mass production inspection as a serious defect, an image of the defect is stored in the serious defect image storage unit as a serious defect image in a state of being associated with the adjusted object inspection data set.

6. The inspection device according to claim 1, wherein: If the input unit has accepted an input of a defect detected by the test inspection as a serious defect, an image of the defect is stored in the serious defect image storage unit as a serious defect image in a state of being associated with the object inspection data set.

7. The inspection device according to any one of claims 1 to 6, wherein: The plurality of inspection data sets are classified into a plurality of groups according to the type of surface treatment and / or the color of solder resist of the corresponding substrate type. The other inspection data sets used for the confirmation inspection are restricted to belong to the same group as the object inspection data set.

8. An inspection method, comprising inspecting a substrate using an inspection unit, wherein: The inspection unit performs inspection processing on the captured image of the substrate using an inspection data set indicating position information of a plurality of inspection areas on the substrate and indicating the type of inspection and an inspection threshold for each inspection area, thereby detecting defects of the substrate. The inspection method comprises: a) step of preparing a plurality of inspection data sets used in the inspection process for a plurality of substrate types respectively; b) step of preparing a plurality of severe defect images respectively associated with any one of the plurality of inspection data sets; c) a step of causing the inspection unit to perform the inspection process on captured images of some substrates of the manufacturing batch as a test inspection using an object inspection data set for a substrate type of the manufacturing batch when inspecting a manufacturing batch; d) if the inspection threshold of the object inspection data set is changed according to the result of the test inspection, the inspection unit is caused to perform a new test inspection using the object inspection data set after the inspection threshold is changed, thereby obtaining an adjusted object inspection data set after the inspection threshold is adjusted; e) a step of applying the adjusted inspection threshold represented by the adjusted object inspection data set as the inspection threshold corresponding to the adjusted inspection threshold in other inspection data sets for other substrate types, to obtain an applied inspection data set; and f) Step of causing the inspection section to perform the inspection process on the serious defect image associated with the other inspection dataset using the applied inspection dataset as a confirmation inspection.

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