Calibration method and manufacturing method of electronic components

Abstract

To provide a calibration method for performing calibration of a camera included in a cutting device with relatively high accuracy, and a method for manufacturing an electronic component.SOLUTION: A calibration method is a method for calibrating a camera included in a cutting device. The cutting device is configured to cut a package substrate to manufacture an electronic component and perform inspection of the appearance of the electronic component based on first image data. The first image data is generated by picking up an image of the electronic component arranged on a table with the camera. The calibration method includes the steps of: picking up an image of a plate for calibration arranged on the table with the camera to generate second image data; calculating, before performing calibration of the camera, the relative inclination between the plate for calibration and the camera based on the second image data; and performing the calibration after the calculation of the relative inclination.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a calibration method and a manufacturing method for electronic components. [Background technology]

[0002] Japanese Patent Laid-Open Publication No. 2019-201143 (Patent Document 1) discloses an inspection method for measuring the pixel size of an imaging means included in a processing device. In this inspection method, an inspection jig is used to measure the pixel size. A pattern and a two-dimensional barcode recording the width of the pattern are formed on the surface of the inspection jig. In this inspection method, an image of the pattern formed on the surface of the inspection jig is captured, and the number of pixels corresponding to the width of the pattern is measured. The pixel size is then calculated by dividing the width of the pattern read from the two-dimensional barcode by the number of pixels corresponding to the width of the pattern (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-201143 Summary of the Invention [Problem to be solved by the invention]

[0004] Visual inspection of electronic components may be performed in a cutting device that manufactures electronic components by cutting package substrates. Visual inspection of electronic components is performed, for example, by capturing images of electronic components placed on an inspection table with a camera. To improve the quality of the visual inspection, it is necessary to improve the accuracy of camera calibration. One example of camera calibration is calculating the pixel size of the camera. However, the technology disclosed in Patent Document 1 does not sufficiently improve the accuracy of camera calibration.

[0005] The present invention has been made to solve such problems, and its object is to provide a calibration method for calibrating a camera included in a cutting device with relatively high precision, and a method for manufacturing electronic components. [Means for solving the problem]

[0006] A calibration method according to one aspect of the present invention is a method for calibrating a camera included in a cutting machine. The cutting machine is configured to manufacture electronic components by cutting package substrates and to perform visual inspection of the electronic components based on first image data. The first image data is generated by capturing an image of the electronic components placed on a table with a camera. The calibration method includes the steps of capturing an image of a calibration plate placed on the table with the camera and generating second image data, calculating a relative tilt between the calibration plate and the camera based on the second image data before calibrating the camera, and performing the calibration after calculating the relative tilt.

[0007] A method for manufacturing an electronic component according to another aspect of the present invention is a method for manufacturing an electronic component using the above-described calibration method, and includes the step of manufacturing the electronic component by cutting the package substrate when the result of the camera calibration satisfies a predetermined condition. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a calibration method for calibrating a camera included in a cutting device with relatively high accuracy, and a method for manufacturing electronic components. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 2 is a plan view schematically showing the cutting device. [Figure 2] FIG. 2 is a side view schematically showing a spindle portion. [Figure 3] FIG. 10 is a diagram schematically illustrating an inspection performed by a second optical inspection camera. [Figure 4]FIG. 1 is a diagram schematically illustrating a hardware configuration of a computer. [Figure 5] FIG. 10 is a diagram illustrating a second optical inspection camera when capturing an image of a calibration plate. [Figure 6] FIG. 1 is a perspective view schematically illustrating an example of a calibration jig. [Figure 7] FIG. 2 is a diagram schematically illustrating a plane of a calibration plate. [Figure 8] FIG. 10 is a diagram illustrating a second optical inspection camera when capturing an image of a standard test piece. [Figure 9] FIG. 1 is a perspective view schematically illustrating an example of a jig for maintenance. [Figure 10] FIG. 2 is a diagram schematically illustrating an example of a pattern portion. [Figure 11] FIG. 2 is a diagram schematically illustrating an example of a pattern on a lead surface of a QFN package. [Figure 12] FIG. 10 is a diagram schematically illustrating an example of a pattern on the ball surface of a BGA package. [Figure 13] FIG. 10 is a diagram schematically illustrating an example of a pattern on a molded surface of a package. [Figure 14] 10 is a flowchart showing an operation procedure performed after the cutting device is assembled. [Figure 15] 10 is a flowchart showing an operation procedure performed at the timing of maintenance of the cutting device. DETAILED DESCRIPTION OF THE INVENTION

[0010] An embodiment according to one aspect of the present invention (hereinafter also referred to as "the present embodiment") will be described in detail below with reference to the drawings. Note that the same or corresponding parts in the drawings are designated by the same reference numerals, and their description will not be repeated. Furthermore, for ease of understanding, each drawing is drawn schematically with objects appropriately omitted or exaggerated.

[0011] [1. Configuration] <1-1. Overall configuration of the cutting device> 1 is a plan view schematically showing a cutting apparatus 1 used in a calibration method according to the present embodiment. The cutting apparatus 1 is configured to cut a package substrate (an object to be cut) to separate the package substrate into a plurality of electronic components (package components). In the package substrate, a substrate or lead frame on which a semiconductor chip is mounted is sealed with resin.

[0012] Examples of package substrates include BGA (Ball Grid Array) package substrates, LGA (Land Grid Array) package substrates, CSP (Chip Size Package) package substrates, LED (Light Emitting Diode) package substrates, and QFN (Quad Flat No-leaded) package substrates.

[0013] The cutting device 1 is configured to inspect each of the plurality of individual electronic components. In the cutting device 1, an image of each electronic component is captured and each electronic component is inspected based on the image. Inspection data is generated through the inspection, and each electronic component is classified as either a "good product" or a "defective product."

[0014] In this example, a package substrate P1 is used as the object to be cut, and the package substrate P1 is divided into a plurality of electronic components S1 by a cutting device 1. Hereinafter, of the two surfaces of the package substrate P1, the surface that is sealed with resin will be referred to as the mold surface, and the surface opposite to the mold surface will be referred to as the ball / lead surface.

[0015] As shown in FIG. 1, the cutting apparatus 1 includes, as its components, a cutting module A1 and an inspection and storage module B1. The cutting module A1 is configured to manufacture a plurality of electronic components S1 by cutting a package substrate P1. The inspection and storage module B1 is configured to inspect each of the manufactured plurality of electronic components S1 and then store the electronic components S1 in a tray. In the cutting apparatus 1, each component is detachable and replaceable with respect to the other components.

[0016] The cutting module A1 mainly includes a substrate supply unit 3, a positioning unit 4, a cutting table 5, a spindle unit 6, and a transport unit .

[0017] The substrate supply unit 3 pushes out the package substrates P1 one by one from a magazine M1 that accommodates a plurality of package substrates P1, thereby supplying the package substrates P1 one by one to the positioning unit 4. At this time, the package substrate P1 is positioned with the ball / lead surface facing upward.

[0018] The positioning unit 4 positions the package substrate P1 by placing the package substrate P1 pushed out from the substrate supply unit 3 on the rail portion 4a. Thereafter, the positioning unit 4 transports the positioned package substrate P1 to the cutting table 5.

[0019] The cutting table 5 holds the package substrate P to be cut. In this example, a cutting device 1 having a twin-cut table configuration with two cutting tables 5 is illustrated. The cutting table 5 includes a holding member 5a, a rotation mechanism 5b, and a movement mechanism 5c. The holding member 5a holds the package substrate P1 transported by the positioning unit 4 by suction from below. The rotation mechanism 5b can rotate the holding member 5a in the θ1 direction in the figure. The movement mechanism 5c can move the holding member 5a along the Y axis in the figure.

[0020] The spindle unit 6 cuts the package substrate P1 to separate the package substrate P1 into a plurality of electronic components S1. In this example, a cutting device 1 having a twin-spindle configuration with two spindle units 6 is shown. The spindle units 6 are movable along the X-axis and Z-axis in the figure. However, the cutting device 1 may also have a single-spindle configuration with one spindle unit 6.

[0021] Fig. 2 is a side view schematically showing the spindle portion 6. As shown in Fig. 2, the spindle portion 6 includes a blade 6a, a rotating shaft 6c, a first flange 6d, a second flange 6e, and a fastening member 6f.

[0022] The blade 6a rotates at high speed to cut the package substrate P1 and separate the package substrate P1 into a plurality of electronic components S1. The blade 6a is attached to a rotating shaft 6c while being sandwiched between one flange (first flange) 6d and the other flange (second flange) 6e. The first flange 6d and the second flange 6e are fixed to the rotating shaft 6c by fastening members 6f such as nuts. The first flange 6d is also referred to as a rear flange, and the second flange 6e is also referred to as an outer flange.

[0023] The spindle portion 6 is provided with a cutting water nozzle that sprays cutting water toward the blade 6a rotating at high speed, a cooling water nozzle that sprays cooling water, and a cleaning water nozzle that sprays cleaning water to wash away cutting chips, etc. (none of which are shown).

[0024] 1, after the cutting table 5 picks up the package substrate P1, the first position confirmation camera 5d captures an image of the package substrate P1 and confirms the position of the package substrate P1. The confirmation using the first position confirmation camera 5d is, for example, confirmation of the position of a mark provided on the package substrate P1. The mark indicates, for example, the cutting position of the package substrate P1.

[0025] The cutting table 5 then moves toward the spindle unit 6 along the Y-axis in the figure. After the cutting table 5 moves below the spindle unit 6, the cutting table 5 and the spindle unit 6 are moved relative to each other to cut the package substrate P1. Thereafter, the package substrate P1 is imaged by the second position confirmation camera 6b as needed, and the position of the package substrate P1, etc., is confirmed. Confirmation using the second position confirmation camera 6b includes, for example, confirmation of the cutting position and cutting width of the package substrate P1.

[0026] After cutting of the package substrate P1 is completed, the cutting table 5, with the plurality of singulated electronic components S1 held by suction, moves along the Y axis in the direction away from the spindle unit 6. During this movement, the first cleaner 5e cleans and dries the top surfaces (ball / lead surfaces) of the electronic components S1.

[0027] The transport unit 7 picks up the electronic component S1 held on the cutting table 5 from above and transports the electronic component S1 to the inspection table 11 of the inspection and storage module B1. During this transport process, the second cleaner 7a cleans and dries the lower surface (molded surface) of the electronic component S1.

[0028] The inspection and storage module B1 mainly includes an inspection table 11, a first optical inspection camera 12, a second optical inspection camera 13, a placement unit 14, and an extraction unit 15. The first optical inspection camera 12 may be provided in the cutting module A1.

[0029] The inspection table 11 holds the electronic component S1 for optical inspection of the electronic component S1. The inspection table 11 is movable along the X-axis in the figure. The inspection table 11 can also be turned upside down. The inspection table 11 is provided with a holding member that holds the electronic component S1 by suction.

[0030] The first optical inspection camera 12 and the second optical inspection camera 13 capture images of both surfaces (ball / lead surface and mold surface) of the electronic component S1. Various inspections of the electronic component S1 are performed based on the image data generated by the first optical inspection camera 12 and the second optical inspection camera 13. The first optical inspection camera 12 and the second optical inspection camera 13 are each positioned near the inspection table 11 so as to capture images above.

[0031] The first optical inspection camera 12 is provided with an illumination device 12a, and the second optical inspection camera 13 is provided with an illumination device 13a. The illumination device 12a is configured to irradiate light onto the inspection table 11 during inspection by the first optical inspection camera 12. The illumination device 13a is configured to irradiate light onto the inspection table 11 during inspection by the second optical inspection camera 13.

[0032] The first optical inspection camera 12 captures an image of the mold surface of the electronic component S1 being transported to the inspection table 11 by the transport unit 7. The transport unit 7 then places the electronic component S1 on a holding member of the inspection table 11. After the holding member picks up the electronic component S1, the inspection table 11 is turned upside down. The inspection table 11 moves above the second optical inspection camera 13, and the ball / lead surface of the electronic component S1 is imaged by the second optical inspection camera 13. As an example, inspection using the second optical inspection camera 13 will be described below.

[0033] 3 is a diagram schematically illustrating an inspection performed by the second optical inspection camera 13. As shown in FIG. 3, the inspection by the second optical inspection camera 13 is performed with the inspection table 11, which holds the electronic component S1 on its underside, positioned above the second optical inspection camera 13. Specifically, the electronic component S1 held on the inspection table 11 is imaged by the second optical inspection camera 13 to generate image data, and an appearance inspection of the ball / lead surface of the electronic component S1 is performed based on the generated image data. As described above, the appearance inspection of the mold surface of the electronic component S1 is performed by the first optical inspection camera 12.

[0034] 1, a post-inspection electronic component S1 is placed on the placement unit 14. The placement unit 14 is movable along the Y axis in the figure. The inspection table 11 places the post-inspection electronic component S1 on the placement unit 14.

[0035] The extraction unit 15 transfers the electronic components S1 placed in the placement unit 14 to a tray. The electronic components S1 are sorted into "good products" or "defective products" based on the results of inspection using the first optical inspection camera 12 and the second optical inspection camera 13. The extraction unit 15 transfers each electronic component S1 to a good product tray 15a or a defective product tray 15b based on the results of the sorting. That is, good products are stored in the good product tray 15a, and defective products are stored in the defective product tray 15b. When the good product tray 15a and the defective product tray 15b are each filled with electronic components S1, they are replaced with new trays.

[0036] The cutting device 1 further includes a computer 50 and a monitor 20. The monitor 20 is configured to display an image. The monitor 20 is configured with a display device such as a liquid crystal monitor or an organic EL (Electro Luminescence) monitor, for example.

[0037] The computer 50 controls the operation of each part of the cutting module A1 and the inspection and storage module B1, for example, the board supply unit 3, the positioning unit 4, the cutting table 5, the spindle unit 6, the transport unit 7, the inspection table 11, the first optical inspection camera 12, the second optical inspection camera 13, the placement unit 14, the extraction unit 15, and the monitor 20.

[0038] Furthermore, the computer 50 performs various inspections of the electronic component S1 based on, for example, image data generated by the first optical inspection camera 12 and the second optical inspection camera 13. Next, the computer 50 will be described in detail.

[0039] <1-2. Computer hardware configuration> Fig. 4 is a diagram schematically illustrating the hardware configuration of computer 50. As shown in Fig. 4, computer 50 includes a calculation unit 70, an input / output I / F (interface) 90, and a storage unit 80, and each component is electrically connected via a bus.

[0040] The calculation unit 70 includes a CPU (Central Processing Unit) 72, a RAM (Random Access Memory) 74, and a ROM (Read Only Memory) 76. The calculation unit 70 is configured to control each component in the computer 50 and each component in the cutting device 1 in accordance with information processing.

[0041] The input / output I / F 90 is configured to communicate via signal lines with each component included in the cutting device 1. The input / output I / F 90 is used to send data from the computer 50 to each component in the cutting device 1 and to receive data sent from each component in the cutting device 1 to the computer 50.

[0042] Storage unit 80 is, for example, an auxiliary storage device such as a hard disk drive or a solid state drive. Storage unit 80 is configured to store, for example, control program 81. Storage unit 80 may store inspection data generated through inspection using first optical inspection camera 12 and second optical inspection camera 13.

[0043] [2. Quality assurance of visual inspection] As described above, in the cutting device 1, a visual inspection of the mold surface of the electronic component S1 (hereinafter also referred to as the "first visual inspection") is performed based on the image captured by the first optical inspection camera 12, and a visual inspection of the ball / lead surface of the electronic component S1 (hereinafter also referred to as the "second visual inspection") is performed based on the image captured by the second optical inspection camera 13. In each visual inspection, for example, information on the pixel size of each camera (hereinafter also referred to as the "pixel size information") is used. The pixel size (image resolution) refers to the actual length of the object to be imaged that corresponds to one side of each pixel of the camera. For example, if the length of one side of the object imaged by one pixel of the camera is 1 mm, the pixel size is 1 mm.

[0044] The pixel size of each camera is calculated when the camera is calibrated. The calibration of each camera is performed, for example, after the cutting device 1 is installed. The calibration of the first optical inspection camera 12 is performed by using the first optical inspection camera 12 to capture an image of a calibration plate 130 (described later) held in the conveying unit 7. The calibration of the second optical inspection camera 13 is performed by using the second optical inspection camera 13 to capture an image of the calibration plate 130 held on the inspection table 11. The calibration of the cameras will be described in detail later.

[0045] The quality of the first visual inspection is affected by the accuracy of the pixel size information of first optical inspection camera 12. The higher the accuracy of the pixel size information of first optical inspection camera 12, the higher the quality of the first visual inspection. Furthermore, the quality of the second visual inspection is affected by the accuracy of the pixel size information of second optical inspection camera 13. The higher the accuracy of the pixel size information of second optical inspection camera 13, the higher the quality of the second visual inspection.

[0046] The accuracy of the pixel size information of first optical inspection camera 12 is affected by the relative tilt between first optical inspection camera 12 and calibration plate 130 (transport section 7) when calibrating first optical inspection camera 12. The closer the optical axis of first optical inspection camera 12 is to being perpendicular to calibration plate 130 when calibrating first optical inspection camera 12, the higher the accuracy of the pixel size information of first optical inspection camera 12.

[0047] Furthermore, the accuracy of the pixel size information of the second optical inspection camera 13 is affected by the relative tilt between the second optical inspection camera 13 and the calibration plate 130 (inspection table 11) during calibration of the second optical inspection camera 13. The closer the optical axis of the second optical inspection camera 13 is to being perpendicular to the calibration plate 130 during calibration of the second optical inspection camera 13, the higher the accuracy of the pixel size information of the second optical inspection camera 13.

[0048] Furthermore, the quality of the first visual inspection is affected by, for example, the relative tilt between the first optical inspection camera 12 and the electronic component S1 (transport unit 7) during the first visual inspection of the electronic component S1. The closer the optical axis of the first optical inspection camera 12 is to being perpendicular to the electronic component S1 during the first visual inspection, the higher the quality of the first visual inspection. Furthermore, the quality of the second visual inspection is affected by, for example, the relative tilt between the second optical inspection camera 13 and the electronic component S1 (inspection table 11) during the second visual inspection of the electronic component S1. The closer the optical axis of the second optical inspection camera 13 is to being perpendicular to the electronic component S1 during the second visual inspection, the higher the quality of the second visual inspection.

[0049] Thus, in order to ensure the quality of the first visual inspection, it is necessary to manage the relative tilt between the first optical inspection camera 12 and the transport unit 7. Also, in order to ensure the quality of the second visual inspection, it is necessary to manage the relative tilt between the second optical inspection camera 13 and the inspection table 11.

[0050] In the cutting apparatus 1, before calibrating the first optical inspection camera 12, the relative tilt between the first optical inspection camera 12 and the calibration plate 130 (transport unit 7) is calculated. Furthermore, before calibrating the second optical inspection camera 13, the relative tilt between the second optical inspection camera 13 and the calibration plate 130 (inspection table 11) is calculated. The calculation of the relative tilt between the first optical inspection camera 12 and the calibration plate 130 and the calculation of the relative tilt between the second optical inspection camera 13 and the calibration plate 130 are performed using substantially the same method. Here, a method for calculating the relative tilt between the second optical inspection camera 13 and the calibration plate 130 will be described as a representative example.

[0051] FIG. 5 is a diagram schematically illustrating the second optical inspection camera 13 when capturing an image of the calibration plate 130. As shown in FIG. 5, when the second optical inspection camera 13 captures an image of the calibration plate 130, the inspection table 11 is located above the second optical inspection camera 13. A jig 100 is placed on the underside of the inspection table 11. The jig 100 is fixed to a predetermined position on the underside of the inspection table 11 by a fixing member such as a screw. Because the jig 100 is fixed to the inspection table 11 by the fixing member, the position of the jig 100 on the inspection table 11 is a predetermined position. For example, at the predetermined position, the center position of the jig 100 and the center position of the inspection table 11 coincide with each other.

[0052] Fig. 6 is a perspective view that schematically shows an example of a calibration jig 100. As shown in Fig. 6, the jig 100 includes a base 110, a holding plate 120, and a calibration plate 130. Each of the base 110, the holding plate 120, and the calibration plate 130 is a plate-like member that is rectangular in a plan view. The calibration plate 130 is placed in a recess 124 formed in the holding plate 120, and is fixed to the holding plate 120 by the head bearing surfaces of screws 122 pressing against the vicinity of each of the four corners of the calibration plate 130.

[0053] FIG. 7 is a diagram schematically illustrating a plane of the calibration plate 130. As shown in FIG. 7, a predetermined pattern is formed on the calibration plate 130. The predetermined pattern is formed on the calibration plate 130 by, for example, printing or cutting. In this example, a plurality of dots D1 are printed on the calibration plate 130. Information about the predetermined pattern is stored in advance in, for example, the memory unit 80 (FIG. 4). Examples of information about the predetermined pattern include the diameter of the dots D1 and the distance between the dots D1.

[0054] Referring again to FIG. 6 , the holding plate 120 is fixed to the base 110 by pressing the vicinity of each of the four corners of the holding plate 120 with pressing members 114. Each pressing member 114 includes a first surface 114a, a bent portion 114b, and a second surface 114c. The bent portion 114b is bent toward each of the first surface 114a and the second surface 114c. In a plan view of the holding member 114, the first surface 114a and the second surface 114c extend in opposite directions from the bent portion 114b. The second surface 114c is fixed to the base 110 with screws 116, and the first surface 114a presses the holding plate 120 toward the base 110. This fixes the holding plate 120 to the base 110. The base 110 has a plurality of screw holes 112 formed therein. By passing a screw through the screw hole 112, the jig 100 is fixed to a predetermined position on the inspection table 11. When the jig 100 is fixed to the predetermined position on the inspection table 11, the center position of the calibration plate 130 is the same as the center position of the electronic component S1 during the second visual inspection, for example.

[0055] 5, the second optical inspection camera 13 captures an image of the calibration plate 130 included in the jig 100 and generates image data. The cutting device 1 calculates the relative tilt between the second optical inspection camera 13 and the calibration plate 130 based on the generated image data. The cutting device 1 calculates, for example, the relative tilt in each of the θ1 direction, the θ2 direction, and the θ3 direction in the figure. The relative tilt between the second optical inspection camera 13 and the calibration plate 130 is calculated based on, for example, the degree of distortion of the pattern (e.g., multiple dots D1) of the calibration plate 130 in the captured image.

[0056] In this way, in the cutting apparatus 1, the relative tilt between the first optical inspection camera 12 and the calibration plate 130 (transport unit 7) is calculated before calibrating the first optical inspection camera 12. Furthermore, the relative tilt between the second optical inspection camera 13 and the calibration plate 130 (inspection table 11) is calculated before calibrating the second optical inspection camera 13. According to the cutting apparatus 1, the calibration of each camera is performed after confirming that there is no problem with the relative tilt between each camera and the calibration plate 130, so the accuracy of the calibration of each camera can be guaranteed. As a result, the cutting apparatus 1 can guarantee the quality of each appearance inspection.

[0057] After a long period of use of the cutting device 1, for example, the relative tilt between each camera and the conveying unit 7 or the inspection table 11 may change. In such cases, the quality of the visual inspection may deteriorate. Various other factors may also cause the quality of the visual inspection to deteriorate. The cutting device 1 undergoes maintenance to prevent deterioration in the quality of the visual inspection. If it is determined through maintenance that various adjustments for the visual inspection are necessary, the necessary adjustments are made. The maintenance is performed by capturing images of a standard test piece 210 (described below) with each camera. Since the maintenance methods using the first optical inspection camera 12 and the second optical inspection camera 13 are substantially the same, the maintenance method using the second optical inspection camera 13 will be described here as a representative example.

[0058] FIG. 8 is a schematic diagram showing the second optical inspection camera 13 when capturing an image of a standard test piece 210. As shown in FIG. 8, when the second optical inspection camera 13 captures an image of the standard test piece 210, the inspection table 11 is positioned above the second optical inspection camera 13. A jig 200 is placed on the underside of the inspection table 11. The jig 200 is fixed to a predetermined position on the underside of the inspection table 11 by a fixing member such as a screw. Because the jig 200 is fixed to the inspection table 11 by the fixing member, the position of the jig 200 on the inspection table 11 is a predetermined position. For example, at the predetermined position, the center position of the jig 200 and the center position of the inspection table 11 coincide with each other.

[0059] FIG. 9 is a perspective view schematically showing an example of a maintenance jig 200. As shown in FIG. 9, the jig 200 includes a base 110 and a standard test piece 210. The standard test piece 210 is a plate-like member that is rectangular in a plan view. A pattern portion 220 is formed on the standard test piece 210. The pattern portion 220 is formed on the standard test piece 210 by, for example, printing or cutting.

[0060] The standard test piece 210 is fixed to the base 110 by being pressed by the pressing members 114 at two locations near each long side (four locations in total) and by being fastened by the screws 212 at three locations near each long side (six locations in total). As described above, a plurality of screw holes 112 are formed in the base 110. By passing screws through the screw holes 112, the jig 200 is fixed to a predetermined position on the inspection table 11.

[0061] FIG. 10 is a diagram schematically illustrating an example of the pattern unit 220. As shown in FIG. 10, the pattern unit 220 includes QFN patterns 221-225, BGA patterns 231-235, and mark patterns 241-244. Each of the QFN patterns 221-225, BGA patterns 231-235, and mark patterns 241-244 includes patterns of multiple packages of the same type. Each package pattern indicates, for example, a package without visual defects. Furthermore, the size of each of the QFN patterns 221-225, BGA patterns 231-235, and mark patterns 241-244 is equal to or larger than the imaging range of each of the first optical inspection camera 12 and the second optical inspection camera 13.

[0062] Each of the QFN patterns 221-225 includes a pattern of a plurality of QFN packages. The pattern of the QFN packages included in each of the QFN patterns 221-225 indicates the lead surface of the QFN package.

[0063] 11 is a diagram schematically showing an example of a pattern on the lead surface of a QFN package. As shown in FIG. 11, a pattern 229 indicates the lead surface of the QFN package.

[0064] 10, each of QFN patterns 221-225 includes designs for multiple QFN packages of the same size. QFN patterns 221, 222, 223, 224, and 225 include designs for 2 mm square, 3 mm square, 5 mm square, 7 mm square, and 9 mm square QFN packages, respectively. Information regarding the length of each side of each design is stored in advance in, for example, storage unit 80 (FIG. 4).

[0065] Each of the BGA patterns 231-235 includes a plurality of BGA package designs, each of which represents the ball surfaces of the BGA packages.

[0066] 12 is a diagram schematically showing an example of a pattern on the ball surface of a BGA package. As shown in FIG. 12, a pattern 239 indicates the ball surface of the BGA package.

[0067] 10, each of BGA patterns 231-235 includes designs of multiple BGA packages of the same size. BGA patterns 231, 232, 233, 234, and 235 include designs of BGA packages, for example, 2 mm square, 4 mm square, 8 mm square, 10 mm square, and 12 mm square, respectively. Information regarding the length of each side of each design is stored in advance in, for example, storage unit 80.

[0068] Each of the mark patterns 241-244 includes a plurality of package designs. The package designs included in each of the mark patterns 241-244 indicate the molded surface of the package. Each package design includes marks including characters and the like.

[0069] Fig. 13 is a diagram showing an example of a pattern on the molded surface of a package. As shown in Fig. 13, pattern 249 shows the molded surface of the package. A mark including the letters "ABC," for example, is formed on the molded surface.

[0070] 10, each of the mark patterns 241-244 includes a plurality of package designs of the same size. For example, the mark patterns 241, 242, 243, and 244 include package designs of 3 mm square, 4 mm square, 7 mm square, and 12 mm square, respectively. Information regarding the length of each side of each pattern is stored in advance in, for example, the storage unit 80.

[0071] 8, the second optical inspection camera 13 is positioned below the pattern to be imaged among the multiple patterns included in the standard test piece 210. For example, if the electronic component manufactured by the cutting apparatus 1 is a 2 mm square QFN package, the second optical inspection camera 13 is positioned below the QFN pattern 221 of the standard test piece 210. In this state, the second optical inspection camera 13 images the standard test piece 210 and generates image data.

[0072] In cutting device 1, for example, the length of one side of the pattern of the captured QFN package is calculated based on the generated image data. Specifically, the length of one side of the pattern of the QFN package is calculated by multiplying the number of pixels corresponding to one side of the pattern of the QFN package in the captured image by the pixel size calculated during calibration of second optical inspection camera 13. Based on the difference between the calculated length of one side and the length of one side (reference value) stored in memory unit 80, it is determined whether various adjustments for the appearance inspection are necessary.

[0073] In this way, the accuracy of pixel size information is confirmed during maintenance in the cutting device 1. According to the cutting device 1, the appearance inspection of the electronic component S1 is performed after it is confirmed that there is no problem with the accuracy of the pixel size information during maintenance, so that the quality of the appearance inspection of the electronic component S1 can be continuously guaranteed. The operation of the cutting device 1 will be described in detail below.

[0074] [3. Electronic component manufacturing operations] <3-1. Operation after assembling the cutting device> 14 is a flowchart showing an operation procedure performed after assembling the cutting device 1. Referring to FIG. 14, an operator assembles the calibration plate 130 (jig 100) at a predetermined position on the inspection table 11 (step S100). The computer 50 controls the second optical inspection camera 13 to capture an image of the calibration plate 130 fixed to the inspection table 11 (step S105). The computer 50 calculates the relative tilt between the second optical inspection camera 13 and the calibration plate 130 based on the image data generated by the second optical inspection camera 13 (step S110).

[0075] The computer 50 controls the monitor 20 to display the calculated tilt information (step S115). Thereafter, it is determined whether the relative tilt between the second optical inspection camera 13 and the calibration plate 130 falls within a predetermined range. This determination is made, for example, by an operator.

[0076] If it is determined that the relative tilt is not within the predetermined range (NO in step S120), the tilt of at least one of the second optical inspection camera 13 and the calibration plate 130 (inspection table 11) is adjusted (step S125). This tilt adjustment is performed manually by an operator, for example.

[0077] On the other hand, if it is determined that the relative tilt is within the predetermined range (YES in step S120), the computer 50 controls the second optical inspection camera 13 to capture an image of the calibration plate 130 fixed to the inspection table 11 (step S130). The computer 50 performs a calibration process for the second optical inspection camera 13 based on the image data generated by the second optical inspection camera 13 (step S135). For example, the computer 50 calculates the pixel size of the second optical inspection camera 13 based on the image data generated by the second optical inspection camera 13 and information about the predetermined pattern of the calibration plate 130 stored in the memory unit 80. In this way, the second optical inspection camera 13 is calibrated.

[0078] Computer 50 controls monitor 20 to display the calibration result (e.g., the pixel size of second optical inspection camera 13) (step S140). Then, a determination is made as to whether recalibration of second optical inspection camera 13 is necessary (step S145). For example, if the calculated pixel size does not meet the standard, it is determined that recalibration is necessary, and if the calculated pixel size meets the standard, it is determined that recalibration is not necessary. This determination is made, for example, by an operator.

[0079] If it is determined that recalibration of the second optical inspection camera 13 is necessary (YES in step S145), the cutting device 1 is reassembled (step S150) because the cause may lie in the assembly of the cutting device 1. The reassembly of the cutting device 1 is performed, for example, by an operator.

[0080] If it is determined that recalibration of the second optical inspection camera 13 is not necessary (NO in step S145), and if the calibration of the first optical inspection camera 12 has also been completed, the manufacturing of the electronic component S1 in the cutting apparatus 1 is started (step S155). Note that, like the second optical inspection camera 13, the first optical inspection camera 12 also performs the operations corresponding to steps S100-S150.

[0081] In this way, in the cutting apparatus 1, the relative tilt between the first optical inspection camera 12 and the calibration plate 130 (transport unit 7) is calculated before calibrating the first optical inspection camera 12. Furthermore, the relative tilt between the second optical inspection camera 13 and the calibration plate 130 (inspection table 11) is calculated before calibrating the second optical inspection camera 13. According to the cutting apparatus 1, the calibration of each camera is performed after confirming that there is no problem with the relative tilt between each camera and the calibration plate 130, so the accuracy of the calibration of each camera can be guaranteed. As a result, the cutting apparatus 1 can guarantee the quality of each appearance inspection.

[0082] <3-2. Operation during maintenance> Fig. 15 is a flowchart showing an operation procedure performed at the timing of maintenance of the cutting device 1. Referring to Fig. 15, an operator assembles the standard test piece 210 (jig 200) at a predetermined position on the inspection table 11 (step S200). The computer 50 controls the second optical inspection camera 13 to capture an image of the standard test piece 210 fixed to the inspection table 11 (step S205).

[0083] The computer 50 calculates the length of the target area of ​​the standard test piece 210 based on the image data generated by the second optical inspection camera 13 (step S210). The computer 50 calculates, for example, the length of one side of the pattern to be imaged (pattern on the package). The computer 50 compares the calculated length of one side with the length (reference value) of one side of the pattern to be imaged that is stored in advance in the storage unit 80 (step S215).

[0084] The computer 50 determines whether or not adjustment for the visual inspection is necessary based on the comparison result (step S220). For example, if the difference between the calculated length of one side and the reference value is equal to or greater than a first predetermined value, it is determined that adjustment for the visual inspection is necessary, and if the difference between the calculated length of one side and the reference value is less than the first predetermined value, it is determined that adjustment for the visual inspection is not necessary.

[0085] If it is determined that no adjustment for the appearance inspection is required (NO in step S220), and if adjustments related to the first optical inspection camera 12 have also been completed, the manufacturing of the electronic component S1 in the cutting device 1 is started (step S250). Note that, like the second optical inspection camera 13, the first optical inspection camera 12 also performs the operations corresponding to steps S200-S240.

[0086] On the other hand, if it is determined that adjustment for the appearance inspection is necessary (YES in step S220), computer 50 determines whether calibration of second optical inspection camera 13 is necessary (step S225). For example, if the difference between the calculated length of one side and the reference value is equal to or greater than a second predetermined value (second predetermined value > first predetermined value), it is determined that calibration of second optical inspection camera 13 is necessary, and if the difference between the calculated length of one side and the reference value is less than the second predetermined value, it is determined that calibration of second optical inspection camera 13 is not necessary.

[0087] If it is determined that calibration of the second optical inspection camera 13 is necessary (YES in step S225), for example, the operation (calibration flow) shown in the flowchart of FIG. 14 is performed (step S230). On the other hand, if it is determined that calibration of the second optical inspection camera 13 is not necessary (NO in step S225), various parameters that affect the appearance inspection are adjusted. One example of the various parameters is a parameter related to the illuminance of the lighting device 13a. The adjustment of the various parameters is performed, for example, by an operator.

[0088] Thereafter, a determination is made as to whether further adjustment for the visual inspection is necessary (step S240). This determination is made, for example, by an operator. If it is determined that further adjustment is necessary (YES in step S240), the operation of step S200 is performed again. On the other hand, if it is determined that further adjustment is not necessary (NO in step S240) and adjustments related to the first optical inspection camera 12 have also been completed, the manufacturing of the electronic component S1 in the cutting apparatus 1 is started (step S250).

[0089] In this way, in the cutting device 1, the accuracy of the pixel size information is confirmed during maintenance, and the need for recalibration of each camera is determined. According to the cutting device 1, the appearance inspection of the electronic component S1 is performed after it is confirmed that there is no problem with the accuracy of the pixel size information during maintenance, so the quality of the appearance inspection of the electronic component S1 can be continuously guaranteed. [4. Features]

[0090] As described above, in the cutting apparatus 1, the relative tilt between the first optical inspection camera 12 and the calibration plate 130 (transport unit 7) is calculated before calibrating the first optical inspection camera 12. Furthermore, the relative tilt between the second optical inspection camera 13 and the calibration plate 130 (inspection table 11) is calculated before calibrating the second optical inspection camera 13. According to the cutting apparatus 1, the calibration of each camera is performed after confirming that there is no problem with the relative tilt between each camera and the calibration plate 130, so the accuracy of the calibration of each camera can be guaranteed. As a result, the cutting apparatus 1 can guarantee the quality of each appearance inspection.

[0091] The cutting device 1 is an example of a "cutting device" in the present invention. Each of the first optical inspection camera 12 and the second optical inspection camera 13 is an example of a "camera" in the present invention. The package substrate P1 is an example of a "package substrate" in the present invention. The electronic component S1 is an example of an "electronic component" in the present invention. Each of the transport unit 7 and the inspection table 11 is an example of a "table" in the present invention. The calibration plate 130 is an example of a "calibration plate" in the present invention.

[0092] 5. Other Embodiments The concept of the above embodiment is not limited to the embodiment described above. An example of another embodiment to which the concept of the above embodiment can be applied will be described below.

[0093] <5-1> In the above embodiment, the necessity of adjustment for visual inspection is determined during maintenance of the cutting device 1. However, such a determination does not necessarily have to be made. At least, it is sufficient that the relative tilts between the calibration plate 130 and each camera are calculated based on the captured images after the cutting device 1 is installed and before the cameras are calibrated.

[0094] <5-2> Furthermore, in the above embodiment, the relative tilt between calibration plate 130 and first optical inspection camera 12 was calculated before the calibration of first optical inspection camera 12, and the relative tilt between calibration plate 130 and second optical inspection camera 13 was calculated before the calibration of second optical inspection camera 13. However, it is not necessary to calculate the relative tilt between the camera and calibration plate 130 before the calibration of each camera. It is sufficient that the relative tilt between the camera and calibration plate 130 for at least one of the cameras is calculated before the calibration of the camera.

[0095] <5-3> Furthermore, in the above embodiment, the accuracy of the pixel size information for each of the first optical inspection camera 12 and the second optical inspection camera 13 was confirmed during maintenance of the cutting device 1. However, it is not necessary to confirm the accuracy of the pixel size information for both the first optical inspection camera 12 and the second optical inspection camera 13. For example, a configuration may be adopted in which the accuracy of the pixel size information for either the first optical inspection camera 12 or the second optical inspection camera 13 is confirmed.

[0096] <5-4> Furthermore, the calibration of each camera may include calculating the size of the imaging range (field of view size) of each camera.

[0097] <5-5> Furthermore, in the visual inspection of the electronic component S1, corners of the electronic component S1 may be detected. In this case, the corners of the electronic component S1 may be detected based on the amount of change in luminance in the captured image. The parameters adjusted in step S235 of FIG. 15 may include a threshold value for the amount of change in luminance for detecting the corners of the electronic component S1.

[0098] <5-6> 14 and 15 are performed by an operator (person). However, each operation may be performed automatically by the cutting device 1. For example, each decision may be made by the computer 50 instead of by an operator.

[0099] <5-7> Furthermore, a rectangular package pattern was formed on the standard test piece 210. However, the shape of the pattern formed on the standard test piece 210 is not limited to a rectangle. For example, a pattern of a special shape such as a microSD (registered trademark) may be formed on the standard test piece 210. Furthermore, a pattern of a package other than a QFN package or a BGA package (such as an LGA package or a CSP package) may be formed on the standard test piece 210.

[0100] The above describes exemplary embodiments of the present invention. That is, the detailed description and the accompanying drawings are disclosed for the purpose of illustrative explanation. Therefore, some of the components described in the detailed description and the accompanying drawings may be non-essential components for solving the problems. Therefore, just because these non-essential components are described in the detailed description and the accompanying drawings, it should not be immediately recognized that these non-essential components are essential.

[0101] Furthermore, the above-described embodiment is merely an example of the present invention in all respects. Various improvements and modifications can be made to the above-described embodiment within the scope of the present invention. In other words, when implementing the present invention, specific configurations can be appropriately adopted depending on the embodiment. [Explanation of symbols]

[0102] 1 cutting device, 3 substrate supply unit, 4 positioning unit, 4a rail unit, 5 cutting table, 5a holding member, 5b rotation mechanism, 5c moving mechanism, 5d first position confirmation camera, 5e first cleaner, 6 spindle unit, 6a blade, 6b second position confirmation camera, 6c rotation axis, 6d first flange, 6e second flange, 6f fastening member, 7 conveying unit, 7a second cleaner, 11 inspection table, 12 first optical inspection camera, 12a, 13a lighting device, 13 second optical inspection camera, 14 placement unit, 15 extraction unit, 15a tray for good products, 15b tray for defective products, 20 monitor, 50 computer, 70 calculation unit, 72 CPU, 74 RAM, 76 ROM, 80 memory unit, 81 control program, 90 input / output I / F, 100, 200 jig, 110 Base, 120 holding plate, 124 recess, 130 calibration plate, 112 screw hole, 114 holding member, 114a first surface portion, 114b bending portion, 114c second surface portion, 116, 122, 212 screws, 210 standard test piece, 220 pattern portion, 221, 222, 223, 224, 225 QFN patterns, 231, 232, 233, 234, 235 BGA patterns, 241, 242, 243, 244 mark patterns, 229, 239, 249 patterns, A1 cutting module, B1 inspection and storage module, D1 dot, M1 magazine, P1 package substrate, S1 electronic component.

Claims

1. 1. A method for calibrating a camera included in a cutting device, comprising: the cutting device is configured to manufacture electronic components by cutting a package substrate, and to perform a visual inspection of the electronic components based on first image data; the first image data is generated by capturing an image of the electronic component placed on a table with the camera; The calibration method includes: capturing an image of a calibration plate placed on the table with the camera to generate second image data; calculating a relative tilt between the calibration plate and the camera based on the second image data before calibrating the camera; performing the calibration after calculating the relative tilt; and adjusting the tilt of at least one of the calibration plate and the camera when the relative tilt is not within a predetermined range; In the step of performing the calibration, When the relative tilt is within the predetermined range, third image data is generated by capturing an image of the calibration plate with the camera; The calibration method, wherein the calibration is performed based on the third image data.

2. The calibration method of claim 1 , wherein the calibration includes calculating a pixel size of the camera.

3. A method for manufacturing an electronic component using the calibration method according to claim 1 or 2, comprising: A method for manufacturing an electronic component, comprising: manufacturing the electronic component by cutting the package substrate when a result of the calibration satisfies a predetermined condition.

4. The method for manufacturing an electronic component according to claim 3 , further comprising the step of reassembling the cutting device when the result of the calibration does not satisfy the predetermined condition.

Images