Cutting device and method of manufacturing a cut product

Abstract

A cutting device (1) that forms a groove in a second face (41b) of a lead frame (41) of a cutting object (4) includes a cutting table (22), a light source (33) that irradiates light to the second face (41b) of the cutting object (4) placed on the cutting table (22), a shielding member (34) that shields a part of the light emitted from the light source (33), a photographing mechanism (31) that acquires a photographed image of the second face (41b), a height changing mechanism (32) that can change the height of the photographing mechanism (31), and a calculation unit (35) that can perform analysis processing of the photographed image. The photographing mechanism (31) includes a lens (31b) that condenses the light to the second face (41b) and a photographing unit (31a) that can acquire the photographed image of the second face (41b). The photographing unit (31a) acquires the photographed image at a plurality of different heights, and the calculation unit (35) calculates the height position of the second face (41b) based on the focus state of the shielding member (34) in the plurality of photographed images (31d).

Description

Technical Field

[0001] This invention relates to a cutting device and a method for manufacturing a cut product. Background Technology

[0002] Conventionally, lead frames, which hold semiconductor chips or the like, are sealed in resin and then cut into single-piece form using a dicing device. This allows for the manufacture of multiple electronic components. These electronic components are electrically connected to external wiring via lead frames extending from the semiconductor chips. Depending on the type of electronic component, sometimes the lead frame is not completely cut along its thickness. Instead, a groove is formed by cutting to approximately half the thickness of the lead frame with a wider cutter, and then the lead frame is completely cut off with a narrower cutter (see, for example, Patent Document 1). When the lead frame is cut in this way, a step is formed at the end of the lead frame.

[0003] Patent Document 1 discloses a QFN (QuadFlat Non-leaded package) with steps on the lead frame (electrodes in Patent Document 1). The steps on the lead frame are formed by the method described above.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2019-036660 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] In manufacturing a QFN of the wettable flank type with steps on the lead frame, as disclosed in Patent Document 1, it is not necessary to completely cut the lead frame when forming a groove to approximately half the thickness of the lead frame. Therefore, before forming the groove, it is necessary to measure the height position of the lead frame and set the cutting amount of the lead frame based on the measurement result. However, Patent Document 1 does not disclose a method for measuring the height position of the lead frame, leaving room for improvement.

[0009] Therefore, a cutting device capable of determining the height position of the lead frame and a method for manufacturing the cut product are desired.

[0010] Solution for solving the problem

[0011] One embodiment of the cutting apparatus of the present invention is a cutting apparatus in which a resin layer is formed on the first surface of a cutting object, and a groove is formed on the second surface opposite to the first surface. The apparatus includes: a cutting worktable for holding the cutting object; a light source for irradiating light onto one side of the second surface of the cutting object held on the cutting worktable; a shielding member disposed along the path of the light propagating from the light source to the cutting object, for shielding a portion of the light emitted from the light source; an imaging mechanism for acquiring an image of one side of the second surface of the cutting object; and a height changing mechanism for changing the height of the imaging mechanism. The imaging mechanism includes: a lens disposed on the path of light on a side closer to the object to be cut than the shielding member, so that the light from the light source is focused onto the second surface; and an imaging unit disposed opposite to the cutting table relative to the object to be cut, capable of acquiring the image by incident light reflected from the object to be cut, the imaging unit acquiring the image at multiple different heights changed by the height changing mechanism, and the computing unit calculating the height position of the second surface based on the focus state of the shielding member in multiple images of the image.

[0012] One embodiment of the method for manufacturing cut articles of the present invention includes: a groove forming step, in which the groove is formed on the object to be cut using the cutting device described above; and a single-piece cutting step, in which the object to be cut having the groove is cut to single-piece into a plurality of cut articles.

[0013] Invention Effects

[0014] According to embodiments of the present invention, a cutting device capable of measuring the height position of a lead frame and a method for manufacturing a cut product can be provided. Attached Figure Description

[0015] Figure 1 This is a top view of the packaging substrate.

[0016] Figure 2 yes Figure 1 Sectional view along line II-II.

[0017] Figure 3 This is a top view of the cutting device.

[0018] Figure 4 This is the front view of the cutting device.

[0019] Figure 5A This is a cross-sectional view showing the groove forming process of the packaging substrate using a cutting device.

[0020] Figure 5BThis is a cross-sectional view showing the monolithization process of the packaging substrate using a cutting device.

[0021] Figure 5C It is a three-dimensional diagram showing the electronic components after being cut into single pieces using a cutting device.

[0022] Figure 6 This is a schematic diagram showing the configuration of a measuring unit that indicates the unfocused state of the shielding component.

[0023] Figure 7 This is a partial top view showing the substrate with the cross mark.

[0024] Figure 8 This is a diagram illustrating the process of calculating the peak contrast value using a measurement unit.

[0025] Figure 9 It is a graph representing the peak contrast value relative to the distance between the retaining column and the second surface.

[0026] Figure 10 This is a flowchart illustrating the process of calculating the distance between the retaining column and the second surface.

[0027] Figure 11 This is a schematic diagram showing the structure of the measuring unit that indicates the focusing state of the shielding component. Detailed Implementation

[0028] Hereinafter, embodiments of the cutting apparatus and the method for manufacturing the cut article of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the embodiments described below are examples for illustrating the method for manufacturing the cutting apparatus and the cut article, and are not intended to limit the method for manufacturing the cutting apparatus and the cut article to these embodiments. Therefore, the method for manufacturing the cutting apparatus and the cut article of the present invention can be implemented in various ways as long as it does not depart from its spirit.

[0029] A substrate containing semiconductor chips and other components is sealed with resin to become a package substrate, and then cut to create individual wafers. This process produces multiple electronic components. A specialized cutting device is used to cut the resin-sealed package substrate.

[0030] Resin sealing of a substrate is performed by placing the substrate in a molding die of a resin molding apparatus and supplying molten liquid resin into the mold. The molten resin can be either a thermoplastic resin or a thermosetting resin. Thermosetting resins decrease in viscosity upon heating and polymerize and solidify upon reheating, becoming cured resins. In the case of resin sealing a substrate to which components such as semiconductor chips are fixed, it is desirable to use a thermosetting resin. The sealing resin protects the components fixed to the substrate.

[0031] A dicing apparatus manufactures multiple electronic components by dicing a packaged substrate. Here, the term "dicing" encompasses both separating the object to be diced into multiple individual pieces and removing a portion of the object to be diced to form a groove in the thickness direction. Hereinafter, a dicing that separates the object to be diced into multiple individual pieces is sometimes referred to as a full cut, while a dicing that removes a portion of the object to be diced without separating it and forms a groove in the thickness direction is sometimes referred to as a half cut. The packaged substrate will be described first, followed by the dicing apparatus for dicing the packaged substrate.

[0032] [Structure of the packaging substrate]

[0033] Figure 1 This is a top view of the packaging substrate 4 (an example of a cut object) in this embodiment. Figure 2 yes Figure 1 A sectional view along line II-II. In this embodiment, the type of packaging substrate 4 is not particularly limited. The packaging substrate 4 is, for example, a QFN with wettable sides. Figure 1 and Figure 2 As shown, the packaging substrate 4 has a rectangular plate-shaped substrate 41 (an example of a lead frame) formed of a metal such as a copper plate and a rectangular resin layer 42 that seals one side of the substrate 41 with resin. Hereinafter, the side of the substrate 41 on which the resin layer 42 is formed will be referred to as the first side 41a, and the side opposite to the first side 41a will be referred to as the second side 41b. A lead frame can be used as the substrate 41.

[0034] In this embodiment, a plurality of semiconductor chip mounting portions (die pads, not shown) are arranged in a matrix on the first surface 41a of the lead frame (substrate 41). Semiconductor chips, resistors, capacitors, and other electronic components 43 are fixed to each semiconductor chip mounting portion. In this embodiment, two electronic components 43 are fixed in the short dimension direction and six in the long dimension direction, for a total of 12 electronic components 43. The substrate 41 is made of metals such as copper (Cu) or Fe-Ni alloy and is conductive. A lead-free metal plating layer or a lead-free solder plating layer (not shown) is pre-formed on most of the surface of the substrate 41. A plurality of leads, serving as terminals for connection to the outside, are arranged around each die pad. These leads are connected to metal frames, i.e., tie bars, arranged in a grid pattern in the substrate 41. Furthermore, a plurality of electrodes (not shown) provided on each electronic component 43 are electrically connected to the leads arranged around the die pads via bonding wires made of gold or copper wires.

[0035] In this embodiment, the substrate 41 is composed of a rectangular usable area 411 and a non-usable area 412 surrounding the usable area 411. The non-usable area 412 is the area including the outer edge of the substrate 41, which is not used as a product and is removed after cutting. On the other hand, the usable area 411 is the area used as a product, which includes the chip pads, leads, and connectors of the lead frame described above. The resin layer 42 is formed into a rectangle to cover the usable area 411 of the substrate 41 and a portion of the non-usable area 412 outside the usable area 411. That is, the electronic components 43 and bonding wires disposed in the usable area 411 are sealed by the resin layer 42. By forming a resin layer 42 like this, the first surface 41a of the substrate 41 and the end face of the resin layer 42 ( Figure 2 Between the upper and lower surfaces, a step of resin layer 42 thickness is formed. It should be noted that the substrate 41 constituting the packaging substrate 4 is not limited to the lead frame.

[0036] [Composition of the cutting device]

[0037] Figure 3 , Figure 4 This describes the cutting apparatus 1 of this embodiment. The cutting apparatus 1 mainly includes a cutting unit 10 (an example of a first cutting mechanism and a second cutting mechanism), a holding unit 20, a measuring unit 30, and a control unit 50. Specifically, in this cutting apparatus 1, the packaging substrate 4 held in the holding unit 20 is cut by the cutting unit 10. Before cutting, the measuring unit 30 measures the height position of the second surface 41b of the substrate 41 used for cutting the packaging substrate 4. Furthermore, the control unit 50 controls a series of cutting processes.

[0038] The cutting apparatus 1 may also include units other than those described above. For example, the cutting apparatus 1 may also include: a substrate supply unit for supplying the packaging substrate 4, an inspection unit for inspecting the packaging substrate 4 and / or electronic components 40 (an example of a cut product), a cleaning unit for cleaning and / or drying the cut electronic components 40, and a transport unit for transporting the cut electronic components 40 to the receiving portion, etc. Hereinafter, the configuration of the cutting unit 10, the holding unit 20, the measuring unit 30, and the control unit 50 will be described in detail. It should be noted that, in this embodiment, as... Figure 3 , Figure 4 As shown, the direction perpendicular to the plate surface of the tool 11 described later is defined as the X-axis direction. Furthermore, the direction perpendicular to the X-axis direction and parallel to the mounting surface 22a of the worktable 22 (an example of a cutting worktable) is called the Y-axis direction, and the direction perpendicular to the mounting surface 22a, that is, the direction perpendicular to both the X-axis and Y-axis directions, is called the Z-axis direction.

[0039] like Figure 3 , Figure 4As shown, the cutting unit 10 is configured to cut the packaging substrate 4, positioned above the holding unit 20. The cutting unit 10 includes a cutter 11, a spindle 13, and a spindle moving mechanism (not shown) that moves the spindle 13 to a desired position within the cutting apparatus 1. The spindle 13 includes a rotating shaft 13a, described later, that rotates the cutter 11. The rotating shaft 13a of the spindle 13 extends along the X-axis. That is, the rotating shaft 13a and the cutter 11 rotate about the X-axis. The spindle 13 is configured such that the spindle moving mechanism (not shown) allows for... Figure 3 and Figure 4 The spindle moves along the X and Z axes. The operation of the spindle moving mechanism, i.e., the movement of the spindle 13, and its position in the X and Z axes are controlled by the control unit 50, which will be described later. Hereinafter, it will sometimes be referred to as... Figure 3 and Figure 4 The Z-axis direction is referred to as the height direction of the spindle 13 or the tool 11. It should be noted that the control unit 50 can determine the position of the spindle 13 in the X-axis and Z-axis directions based on information from the spindle moving mechanism.

[0040] The cutting tool 11 has a circular plate shape and a cutting edge formed on its outer periphery. The cutting tool 11 is detachably mounted on the shaft 13a of the spindle section 13. The cutting tool 11 is configured to move together with the spindle section 13 on which it is mounted. Figure 3 and Figure 4 It moves along the X-axis and Z-axis.

[0041] The cutting tool 11 mounted on the rotating shaft 13a of the spindle section 13 is configured such that it rotates at high speed by transmitting rotation from the spindle section 13 via the rotating shaft 13a, and its outer peripheral cutting edge performs half-cutting and full-cutting on the package substrate 4. Hereinafter, the cutting tool 11 for half-cutting is referred to as the first cutting tool 11a (an example of a cutting tool), and the cutting tool 11 for full-cutting is referred to as the second cutting tool 11b, and the cutting tool 11 is used as a collective term for the first cutting tool 11a and the second cutting tool 11b. The first cutting tool 11a has a first thickness, and the second cutting tool 11b has a second thickness that is less than the first thickness. That is, the thickness of the second cutting tool 11b is thinner than the thickness of the first cutting tool 11a (see reference). Figure 5A , Figure 5B In this embodiment, either the first tool 11a or the second tool 11b is mounted relative to the spindle portion 13 for cutting. The first tool 11a and the second tool 11b can be mounted, detached, and exchanged relative to the spindle portion 13.

[0042] The holding unit 20 is configured to include a worktable 22 and a worktable moving mechanism 24. The encapsulation substrate 4 is placed with the resin layer 42 in contact with the mounting surface 22a of the worktable 22 and is held by means of air adsorption or the like. The worktable moving mechanism 24 can move the worktable 22 along the Y-axis and rotate it 90 degrees around the Z-axis. While held in the holding unit 20, the encapsulation substrate 4 can be cut along its long and short dimensions by moving the worktable 22 relative to the cutter 11 in the Y-axis direction and rotating it around the Z-axis.

[0043] It should be noted that as long as the spindle 13 can move relative to the worktable 22, there is no problem. Therefore, it is also possible to move the worktable 22 in the X-axis direction instead of moving the spindle 13 in the X-axis direction. Furthermore, it is also possible to move the worktable 22 in the Z-axis direction instead of moving the spindle 13 in the Z-axis direction. Moreover, it is also possible to move the spindle 13 in the Y-axis direction instead of moving the worktable 22 in the Y-axis direction.

[0044] like Figures 5A to 5C As shown, in the case of manufacturing electronic components 40 by cutting the packaging substrate 4, the packaging substrate 4 is cut in the order of half-cutting and full-cutting. That is, the manufacturing method of electronic components 40 includes: a groove forming process in which the substrate 41 of the packaging substrate 4 is half-cut using the cutting device 1 to form a half-cut groove 44 (an example of a groove) of a desired depth, and a monolithicization process in which the packaging substrate 4 with the groove is fully cut to monolithize the packaging substrate 4 into multiple electronic components 40. It should be noted that... Figures 5A to 5C The cross-section of the packaging substrate 4 shown is a cross-section along the length direction.

[0045] exist Figure 5A In the groove forming process shown, a first tool 11a is mounted on the rotating shaft 13a of the main spindle 13. Then, the packaging substrate 4 is placed on the worktable 22 with its longitudinal direction parallel to the surface of the first tool 11a. While the packaging substrate 4 is held on the worktable 22, the first tool 11a is positioned between adjacent electronic components 43 (see reference 11a) among a plurality of electronic components 43 fixed to the packaging substrate 4. Figure 1Between the components 43 and the substrate 43. Then, while rotating the first cutter 11a at that location, the stage 22 is moved along the Y-axis, thereby half-cutting the long dimension of the packaging substrate 4 along the Y-axis by the first cutter 11a, forming a (row of) half-cut grooves 44 on the substrate 41 of the packaging substrate 4. Specifically, in the groove forming process, a portion of the substrate 41 (e.g., about half the thickness of the substrate 41 (lead frame)) is removed in the thickness direction of the packaging substrate 4. After forming one half-cut groove 44, the first cutter 11a is moved in the X-axis direction, positioning the first cutter 11a between other adjacent electronic components 43. Then, the stage 22 is moved again along the Y-axis to form new half-cut grooves 44 on the packaging substrate 4. This operation is repeated to form multiple (e.g., three in the long dimension direction of the packaging substrate 4) half-cut grooves 44.

[0046] Next, while holding the packaging substrate 4, the worktable 22 is rotated 90 degrees around the Z-axis so that the short dimension direction of the packaging substrate 4 is parallel to the surface of the first cutter 11a. Then, similarly as described above, while rotating the first cutter 11a at this location, the worktable 22 is moved along the Y-axis, forming a semi-cut groove 44 in the short dimension direction of the packaging substrate 4 using the first cutter 11a. This operation is repeated to form multiple semi-cut grooves 44 (for example, seven in the short dimension direction of the packaging substrate 4). Thus, the groove forming process is completed by forming a grid-like semi-cut groove 44 extending in both the long and short dimension directions of the packaging substrate 4.

[0047] exist Figure 5B In the monolithic process shown, firstly, the first tool 11a is removed from the spindle 13, and the second tool 11b is installed. Then, a full cut is performed using the second tool 11b. Specifically, approximately at the center of the extending direction of the half-cut groove 44, the second tool 11b cuts along the half-cut groove 44 to remove the remaining portion of the substrate 41 and the resin layer 42. Since the cutting sequence is the same as in the half-cut case, detailed descriptions are omitted. Thus, the grid-like half-cut groove 44 is cut and separated, as... Figure 5C As shown, the packaging substrate 4 is monolithically divided into multiple (12 in this embodiment) electronic components 40.

[0048] The measuring unit 30 measures the height position of the second surface 41b of the substrate 41 of the packaging substrate 4. By accurately measuring the height position of the second surface 41b, a semi-cut groove 44 of the desired depth can be formed in the substrate 41 using the first tool 11a. Figure 6As shown, the measuring unit 30 includes: a shooting mechanism 31, a height changing mechanism 32, a light source 33, a shielding member 34, a computing unit 35, a semi-reflective mirror 36 (an example of a reflective mirror), and a CCS (Contact Cutter Setup) block 37 (an example of a reference block).

[0049] The imaging mechanism 31 has the function of imaging the second surface 41b of the substrate 41 of the packaged substrate 4, and includes a camera 31a (an example of an imaging unit), a lens 31b, and a square-shaped first tube 31c connecting the camera 31a and the lens 31b. The camera 31a images the second surface 41b using an imaging element (not shown) such as a built-in CCD or CMOS and captures an image 31d (see reference 31d). Figure 8 (a) Therefore, the light-receiving surface of the imaging element of camera 31a is configured to face the second surface 41b. Lens 31b focuses the light reflected from the second surface 41b and causes it to pass through (propagate) inside the first tube 31c, forming an image on the imaging element of camera 31a. Therefore, lens 31b is positioned between camera 31a and the second surface 41b. Camera 31a is mounted at one end of the first tube 31c, and lens 31b is mounted at the other end of the first tube 31c. That is, the imaging mechanism 31 is integrated.

[0050] The height adjustment mechanism 32 includes a main column 32a extending along the Z-axis and a retaining column 32b extending from the main column 32a along the X-axis. The retaining column 32b is configured to move relative to the main column 32a along the Z-axis. The retaining column 32b holds the first cylinder 31c, and the shooting mechanism 31 also moves along the Z-axis due to the movement of the retaining column 32b. The movement of the retaining column 32b is, for example, performed by a motor (not shown). The control unit 50 can determine the height position of the retaining column 32b, i.e., the height position of the camera 31a, by controlling the number of rotations of the motor when the retaining column 32b moves up and down.

[0051] Light source 33 illuminates the second surface 41b of substrate 41 of the encapsulation substrate 4, which is composed of LEDs or the like. Light source 33 is mounted at one end of a rectangular cylindrical second cylinder 33a, and the light emitted from light source 33 travels inside the second cylinder 33a. The other end of the second cylinder 33a is connected to the side of the first cylinder 31c, and the light from light source 33 enters the internal space of the first cylinder 31c. That is, a hole is formed on the side of the first cylinder 31c, and the second cylinder 33a closes this hole. The second cylinder 33a extends along the X-axis.

[0052] The first cylinder 31c has a semi-reflective mirror 36 inside. This semi-reflective mirror 36 reflects light that has passed through the interior of the second cylinder 33a along the X-axis and propagates it along the Z-axis toward the second surface 41b. The semi-reflective mirror 36 allows light reflected from the second surface 41b and focused by the lens 31b to pass directly through and enter the imaging element of the camera 31a. That is, light emitted from the light source 33 passes through the interior of the second cylinder 33a and enters the first cylinder 31c, where it is reflected by the semi-reflective mirror 36 toward the second surface 41b. Then, after reflection from the second surface 41b, it passes through the lens 31b and the semi-reflective mirror 36 and enters the camera 31a. Thus, the imaging element of the camera 31a can acquire an image 31d of the second surface 41b.

[0053] A shielding member 34 is disposed inside the second cylinder 33a. The shielding member 34 is a rectangular frame. That is, the inner side (center) of the shielding member 34 forms an opening 34a with a similar shape (i.e., rectangular). When light from the light source 33 enters the second cylinder 33a, the light passing through the central region of the second cylinder 33a and incident on the portion adjacent to the shielding member 34, i.e., the opening 34a disposed on the inner side of the shielding member 34, passes through (propagates) through the opening 34a and proceeds towards the first cylinder 31c inside the second cylinder 33a. On the other hand, light incident on the shielding member 34 through the outer edge region of the second cylinder 33a cannot pass through the shielding member 34 and is reflected or absorbed. That is, the shielding member 34 blocks the light incident from the light source 33 through the outer edge region. The outer edge region is the region of the surface constituting the second cylinder 33a that is closer to the inner side. The shielding member 34 is mounted on a sliding cylinder 34c that is slidably disposed inside the second cylinder 33a. Thus, the shielding member 34 is configured to move along the X-axis direction by moving the sliding cylinder 34c along the X-axis direction.

[0054] Thus, the shooting mechanism 31, the light source 33, the second tube 33a, the shielding member 34, and the semi-reflective mirror 36 are integrated. All of these are held by the holding column 32b of the height changing mechanism 32, and move along the Z-axis direction as the holding column 32b moves along the Z-axis direction.

[0055] The arithmetic unit 35 is configured to be included in the control unit 50. The control unit 50 includes a processor such as a CPU (Central Processing Unit) and a storage device such as RAM (Random Access Memory) or ROM (Read Only Memory). The arithmetic unit 35 is the processor. The control unit 50 controls the operation of the cutting unit 10, the holding unit 20, and the measuring unit 30 of the cutting apparatus 1 by executing a control program stored in the storage device. Unless otherwise specified, the operation of the cutting apparatus 1 is based on the operating commands of the control unit 50. In the following description, the operating commands of the control unit 50 are generally omitted, but will be described as needed. The control unit 50 can be integrally configured with each unit or separately configured with each unit.

[0056] The calculation unit 35 calculates the height position (absolute position and / or relative position) of the second surface 41b of the substrate 41 of the packaging substrate 4, as measured by the measurement unit 30. In this embodiment, the height position of the second surface 41b of the substrate 41 refers to the height from the reference position to the second surface 41b when any point is taken as the reference position in the height direction (hereinafter referred to as the reference height P). In this embodiment, the reference height P is between the upper surface 37a of the CCS block 37 and the upper surface of the worktable moving mechanism 24.

[0057] CCS block 37 is installed on the side of workbench 22 and can move together with workbench 22.

[0058] [Method for determining the height position of the second surface of the substrate]

[0059] Next, use Figures 6 to 11 The method for determining the height position of the second surface 41b of the substrate 41 of the packaging substrate 4 will be described. Before starting the measurement, the positions of the shielding member 34, the semi-reflective mirror 36, and the lens 31b are adjusted so that when the second surface 41b of the substrate 41 is photographed using the camera 31a, the second surface 41b and the shielding member 34 are found to be in the same focal point in the captured image 31d. It should be noted that... Figure 6 This indicates that the shielding member 34 is not focused on the second surface 41b of the substrate 41. Figure 11 This indicates the state in which the shielding member 34 is focused on the second surface 41b of the substrate 41.

[0060] First, the packaging substrate 4 is placed on the worktable 22 and held in place by means of air adsorption or the like. Then, the imaging mechanism 31, including the camera 31a, is moved above the packaging substrate 4 by the height changing mechanism 32, and then moved along the Z-axis to a predetermined height position (hereinafter also referred to as the predetermined height position) (step S1). The predetermined height position may be, for example, a height position at which the lens 31b is close to the substrate 41 without contacting it. Alternatively, it may be a height position at which the lens 31b separates from the substrate 41 until the camera 31a can photograph the second surface 41b to determine the height position.

[0061] The height position of camera 31a is configured to be known as its height relative to a reference height P. This height position of camera 31a is input to the arithmetic unit 35. Furthermore, the focal distance L of camera 31a in the imaging mechanism 31 is pre-stored in a storage device.

[0062] Light from the light source 33 is shone onto the second surface 41b of the substrate 41 of the packaging substrate 4, and the second surface 41b is photographed using the camera 31a (step S2). At this time, the photograph is taken as shown... Figure 7 A cross mark 41c (an example of a cutting mark) formed on the second surface 41b as shown is acceptable. The cross mark 41c is formed on the edge portion of the second surface 41b, indicating the half-cut and full-cut sections of the substrate 41, i.e., the sections where the tool 11 cuts the encapsulation substrate 4. The cross mark 41c is formed along at least two adjacent sides of the second surface 41b of the rectangular substrate 41 by methods such as printing. The area where the camera 31a takes a picture to determine the height position of the second surface 41b of the substrate 41 can be any part of the second surface 41b. However, it is preferable to obtain the image 31d by photographing the half-cut and full-cut sections of the substrate 41, i.e., the cross mark 41c, because the height position of the cut section of the second surface 41b of the substrate 41 can be determined and the cut section of the encapsulation substrate 4 can be grasped. As a result, a half-cut groove 44 of a desired depth can be formed at the desired cut section of the substrate 41.

[0063] The image acquisition element of camera 31a is as follows Figure 8The captured image 31d is shown in (a). In this embodiment, the shielding member 34 is disposed between the light source 33 and the second surface 41b of the substrate 41, and the light incident on the shielding member 34 is shielded and does not reach the second surface 41b. Therefore, the edge 31e (the part shielded by the shielding member 34) of the captured image 31d taken by the camera 31a becomes dark, and the central part 31f (the part through which light passes through the opening 34a adjacent to the shielding member 34) becomes bright, reflecting the cross mark 41c. That is, in the captured image 31d, the edge 31e is the dark part, and the central part 31f is the bright part. The data of the captured image 31d obtained by taking a picture of the second surface 41b using the camera 31a, and the distance D between the camera 31a and the reference height P (refer to Figure 6 The output is sent to the control unit 50.

[0064] In the control unit 50, the arithmetic unit 35 processes the data of the input captured image 31d, which is configured as follows: Figure 8 As shown in (b), there are multiple columns near the boundary between the edge 31e and the central part 31f (in Figure 8 The pixel values ​​(brightness values) of each pixel in a vertically arranged array (multiple pixels) are summed for each column to calculate the total pixel values ​​for each column. Because... Figure 8 (b) shows the state of the shielding member 34 after it has been focused, therefore as Figure 8 As shown in (c), the total pixel value has two values. Next, as... Figure 8 As shown in (d), the arithmetic unit 35 generates an approximate curve for the sum of pixel values, and further differentiates the approximate curve to generate a curve as shown in (d). Figure 8 The differential curve is shown by the solid line (e). In the differential curve, the differential value is the change in pixel value. Therefore, the differential value represents the contrast between the edge 31e and the center 31f of the captured image 31d, i.e., the contrast value. That is, the generation of the differential curve is synonymous with the calculation of the contrast value. Since the part that becomes the maximum value in the calculated contrast value (differential value) is the part where the pixel value changes the most, the part where the contrast value becomes the maximum value is the boundary between the edge 31e (dark part) and the center 31f (bright part) of the captured image 31d. Hereinafter, the maximum value of the contrast value is sometimes referred to as the peak contrast value. Next, the arithmetic unit 35 extracts the peak contrast value from the contrast value and stores it in the storage device (step S3). It should be noted that the imaging of the second surface 41b of the substrate 41 by the camera 31a at a specified height position, the calculation of the contrast value by the arithmetic unit 35, and the extraction and storage of the peak contrast value can be performed on one cross mark 41c or on multiple cross marks 41c. When multiple cross markers 41c are processed, the arithmetic unit 35 stores the average value of multiple peak contrast values ​​in the storage device.

[0065] After the camera 31a at a predetermined height position captures an image of the second surface 41b of the substrate 41, the arithmetic unit 35 calculates the contrast value, and the peak contrast value is extracted and stored, the camera 31a (holding post 32b) is moved a predetermined distance (No in step S4, step S6). At the moved height position, the capture of the second surface 41b and the extraction of the peak contrast value are performed (steps S2 and S3). This is performed a predetermined number of times, or within a predetermined range at a predetermined height position in the Z-axis direction. After completion (Yes in step S4), the measurement is stopped.

[0066] Because in Figure 8 The image shows the state of the shielding member 34 after it has been focused, therefore Figure 8 The differential curve represented by the solid line in (e) rises sharply towards the peak contrast value, and the peak contrast value itself also increases. That is, the dark and bright areas are clearly separated. However, when the masking member 34 is not in focus (not shown), the area near the boundary between the edge 31e and the center 31f in the image 31d captured by the camera 31a is gray, and the boundary between the edge 31e (dark area) and the center 31f (bright area) cannot be clearly separated. Therefore, the sum of the pixel values ​​in each column parallel to the boundary between the edge 31e and the center 31f rises gently from the dark area to the bright area. The differential curve in this case is as follows: Figure 8 As shown by the dashed line in (e), compared to the solid line (focus state of the masking member 34), the differential curve rises gently toward the peak contrast value, and the peak contrast value itself also decreases. Figure 9 This indicates the relationship between the distance D between the camera 31a and the second surface 41b of the substrate 41 and the peak contrast value.

[0067] according to Figure 9 The peak contrast value changes as the distance D changes. The distance D1 at which the peak contrast value is at its maximum, i.e., the distance at which the contrast is highest, is the distance at which the masking component 34 is focused. Figure 11 As shown, distance D1 is the distance D from the reference height P to the camera 31a when the shielding member 34 is focused on the second surface 41b of the substrate 41 (step S5). At this time, the distance between the camera 31a and the second surface 41b of the substrate 41 is the same as the focal distance L. Therefore, by subtracting the focal distance L from distance D1, the distance D2 (the height position of the second surface 41b) from the reference height P to the second surface 41b is calculated (D2==D1-L).

[0068] Next, the arithmetic unit 35 illuminates the upper surface 37a of the CCS block 37 with light from the light source 33 and acquires an image of the upper surface 37a (not shown; an example of a block image). Then, using the same method as calculating distance D2 (the height position of the second surface 41b) described above, the arithmetic unit 35 calculates the distance D3 from the reference height P to the upper surface 37a of the CCS block 37. Then, based on the difference between distance D2 and distance D3, the arithmetic unit 35 calculates the distance D4 (D4 = D2 - D3) from the upper surface 37a of the CCS block 37 to the second surface 41b of the substrate 41.

[0069] Measurements and distance D4 are performed on multiple locations of the packaging substrate 4, such as the four corners of a rectangular substrate (four locations), or the center of the long side of the rectangular substrate in addition to the four corners (a total of six locations). When the distance D4 values ​​are uneven across multiple locations due to warping or other reasons on the packaging substrate 4, a distance D4 is set such that the depth of the half-cut groove 44 falls within the allowable tolerance regardless of where the cut is made. If a single distance D4 does not result in the depth of the half-cut groove 44 falling within the allowable tolerance at any cut location, two or more distance D4 settings are used to ensure that the depth of the half-cut groove 44 falls within the allowable tolerance at all cut locations.

[0070] Next, the spindle section 13 is moved by the spindle section moving mechanism (not shown) to bring the first tool 11a into contact with the upper surface 37a of the CCS block 37. The contact between the first tool 11a and the CCS block 37 can be detected by any method, such as detecting the continuity between the first tool 11a and the CCS block 37. The method for detecting the continuity between the first tool 11a and the CCS block 37 is described below. The CCS block 37 and the spindle section 13 are made of a conductive material such as metal; for example, the CCS block 37 and the spindle section 13 are pre-connected electrically. Furthermore, since the spindle section 13, the shaft 13a, and the first tool 11a are all made of metal, the spindle section 13 is conductive to the first tool 11a. Therefore, by moving the spindle section 13 along the Z-axis direction via the spindle section moving mechanism, the first tool 11a is brought close to the upper surface 37a of the CCS block 37. When the CCS block 37 is not in contact with the first tool 11a, no electrical connection exists between the CCS block 37, the spindle portion 13, and the first tool 11a. However, at the instant the CCS block 37 contacts the first tool 11a, electrical connection exists between the CCS block 37, the spindle portion 13, and the first tool 11a. This electrical connection is detected using a known method. Detection of electrical connection means that the lowest point of the first tool 11a is located on the upper surface 37a of the CCS block 37.

[0071] From the point where the first cutter 11a contacts the upper surface 37a of the CCS block 37, the spindle section 13 is raised a distance D4 by the spindle section moving mechanism. This brings the first cutter 11a to the same height as the second surface 41b of the substrate 41. Specifically, the height of the first cutter 11a is the height of its lowest point, i.e., the height of the contact point between the first cutter 11a and the upper surface 37a of the CCS block 37. Finally, the spindle section 13 is lowered only by the depth of the half-cut groove 44. At this height, the first cutter 11a is rotated, and the worktable 22 is moved along the Y-axis. This allows a half-cut groove 44 of the desired depth to be formed on the substrate 41. It should be noted that, alternatively, the spindle section 13 can be moved directly from the point where the first cutter 11a contacts the upper surface 37a of the CCS block 37 to the height at which the half-cut groove 44 is formed relative to the substrate 41.

[0072] Thus, by changing the height of the camera 31a (the height of the holding post 32b of the height changing mechanism 32) to capture images of the second surface 41b of the substrate 41, calculate the contrast value of the differential curve, and extract the peak contrast value, the height position of the second surface 41b of the substrate 41 (lead frame) can be calculated based on the reference height P without using expensive devices such as laser sensors, ensuring that the height position of the first cutter 11a is consistent with that of the second surface 41b of the substrate 41. Therefore, the cutting device 1 can be used to half-cut the substrate 41 of the packaged substrate 4 to form a half-cut groove 44 of the desired depth.

[0073] It should be noted that the first tool 11a will wear slightly when forming the half-cut groove 44. Therefore, it is preferable that whenever the half-cut groove 44 is formed, the first tool 11a is brought into contact with the upper surface 37a of the CCS block 37, and the height difference between the second surface 41b of the substrate 41 and the lowest point of the first tool 11a is adjusted to a value that is the distance D4 minus the depth of the half-cut groove 44 before half-cutting.

[0074] Alternatively, the height of the first tool 11a may not be calculated based on the upper surface 37a of the CCS block 37. For example, the height of the shaft 13a of the spindle 13 when the first tool 11a is moved to its lowest point by the spindle moving mechanism may be set as the reference height. Alternatively, the reference height of the first tool 11a may not be consistent with the reference height of the camera 31a and the substrate 41.

[0075] [Other Implementation Methods]

[0076] Other embodiments of the above-described embodiments will be described below. It should be noted that, for ease of understanding, the same terms and reference numerals are used to describe the same components as in the above embodiments.

[0077] (1) In the above embodiment, the first tool 11a and the second tool 11b are interchanged relative to one spindle part 13, but the spindle part 13 used for the first tool 11a and the spindle part 13 used for the second tool 11b may also be separate.

[0078] (2) In the above embodiments, the second side 41b is photographed and the peak contrast value is extracted a predetermined number of times or within a predetermined range, but is not limited thereto. For example, it may be stopped at the stage where the peak contrast value changes from increasing to decreasing. Even so, the distance D1 at which the peak contrast value is the maximum can be obtained.

[0079] (3) In the above embodiment, a sliding cylinder 34c is arranged in the second cylinder 33a, but the second cylinder 33a can also be divided into two, and the sliding cylinder 34c can be slidably arranged in between.

[0080] (4) In the above embodiments, the shielding member 34 is a rectangular frame, but is not limited to this. The shielding member 34 can be any shape as long as the boundary between the part that shields the light source 33 and the part that allows the light to pass through is straight.

[0081] (5) In the above embodiment, the sum of pixel values ​​for each column near the boundary between the edge portion 31e and the central portion 31f in the masking member 34 is calculated in a vertical arrangement, but is not limited thereto. For example, a column near the boundary between the edge portion 31e and the central portion 31f is selected. Figure 8 In the case of (a) being on the upper side of the center of the left and right sides, the total value of the pixel values ​​of each column can also be calculated in a horizontal arrangement.

[0082] (6) In the above embodiment, the camera 31a captures the cross mark 41c, but it can also capture images other than the cross mark 41c.

[0083] (7) In the above embodiment, the cut portions of the half-cut and full-cut substrate 41 are formed with cross marks 41c, but they may be any marks other than cross marks 41c.

[0084] (8) In the above embodiments, the lens 31b is disposed between the semi-reflective mirror 36 and the substrate 41, but it can also be disposed between the semi-reflective mirror 36 and the camera 31a, not only in this part.

[0085] [Summary of the above embodiments]

[0086] Hereinafter, the cutting method, the method for manufacturing the cut product, and the outline of the cutting apparatus 1 described in the above embodiments will be explained.

[0087] <1> A cutting device (1) has a groove (44) formed on a second side (41b) opposite to the first side (41a) of a cutting object (4) on a first side (41a) of a plate-shaped lead frame (41). The cutting device (1) includes: a cutting worktable (22) for holding the cutting object (4); a light source (33) for irradiating light onto one side of the second side (41b) of the cutting object (4) placed on the cutting worktable (22); a shielding member (34) disposed in the path of light propagating from the light source (33) to the cutting object (4) to shield a portion of the light emitted from the light source (33); an imaging mechanism (31) for acquiring an image (31d) of one side of the second side (41b) of the cutting object (4); and a height changing mechanism (32) for changing the image size. The imaging mechanism (31) has a lens (31b) positioned on the side of the object to be cut (4) closer to the shielding member (34) than the object to be cut (4) in the path of light, so that the light from the light source (33) is focused on the second surface (41b); and an imaging unit (31a) positioned opposite the cutting worktable (22) relative to the object to be cut (4), so that the imaging image (31d) can be acquired by incident light reflected from the object to be cut (4). The imaging unit (31a) acquires the imaging image (31d) at multiple different heights changed by the height changing mechanism (32). The calculation unit (35) calculates the height position of the second surface (41b) based on the focusing state of the shielding member (34) in the multiple imaging images (31d).

[0088] In this embodiment, since the height position of the second surface (41b) is calculated based on the focusing state of the masking member (34) in the captured image (31d), the height position of the second surface (41b) can be accurately determined. Therefore, based on the calculated height position, a cutting device (1) can be obtained to form a groove (44) of the desired depth on the second surface (41b) of the object to be cut (4).

[0089] <2> The above <1> In the cutting device (1), the shielding member (34) may be a frame that shields the outer edge region of the light emitted from the light source (33).

[0090] In this embodiment, by blocking a portion of the light emitted from the light source (33) by the shielding member (34), a high-contrast image (31d) can be obtained. Thus, an image (31d) in focus by the shielding member (34) can be obtained accurately.

[0091] <3> The above <1> or <2> In the cutting device (1), the calculation unit (35) may calculate the contrast between the masking member (34) and the part adjacent to the masking member (34) in each of the plurality of captured images (31d), and calculate the height position of the second surface (41b) based on the height of the capturing unit (31a) when the captured image (31d) with the highest contrast among the plurality of calculated contrasts is obtained.

[0092] When the contrast of the captured image (31d) increases, the boundary between the bright and dark areas becomes clear, and the masking member (34) approaches the focusing state. In this embodiment, since the height position of the second surface (41b) is calculated based on the height of the capturing part (31a) when the captured image (31d) with the highest contrast is obtained, the captured image (31d) with the masking member (34) in focus can be accurately obtained.

[0093] <4> The above <1> to <3> In any of the cutting devices (1) described above, the shielding member (34) may be configured to be movable between the light source (33) and the object to be cut (4).

[0094] According to this embodiment, the common focal point of the second surface (41b) and the shielding member (34) in the captured image (31d) can be easily obtained.

[0095] <5> The above <1> to <4> In any of the cutting devices (1) described above, the height of the light source (33) and the shielding member (34) may be changed in conjunction with the change of the height of the shooting unit (31a) carried out by the height changing mechanism (32).

[0096] According to this embodiment, by simply changing the height of the imaging unit (31a), an image (31d) of the second side (41b) can be obtained.

[0097] <6> The above <1> to <5> In any of the cutting devices (1) described above, there may also be a reflector (36) disposed between the shielding member (34) and the lens (31b) in the path of light, so that light is reflected toward the second surface (41b), and the height of the reflector (36) is changed in conjunction with the change of the height of the shooting unit (31a) by the height changing mechanism (32).

[0098] According to this embodiment, by simply changing the height of the imaging unit (31a), an image (31d) of the second side (41b) can be obtained.

[0099] <7> The above <1> to <6> In any of the cutting devices (1) described above, the imaging unit (31a) may also acquire an image (31d) of the cutting mark (41c) used when cutting the object (4) into individual pieces.

[0100] According to this embodiment, the imaging unit (31a) can accurately determine the height position of the cut portion of the second surface (41b) of the object being cut by photographing the cutting mark (41c) used during the cutting of the object being cut (4) and acquiring the photographed image (31d). As a result, a groove (44) of the desired depth can be formed.

[0101] <8> The above <1> to <7> In any of the cutting devices (1) described above, the imaging unit (31a) may acquire a block imaging image of a reference block (37) that serves as a reference height for calculating the height position of the second surface (41b).

[0102] According to this embodiment, the height position of the cutting part of the second side (41b) of the object to be cut can be determined as a relative value based on the block image captured by the reference block (37).

[0103] <9> The above <1> to <8> The cutting device (1) described in any one of the above may also include: a cutting tool (11a) forming a groove (44) on the second surface (41b) of the object to be cut (4); and a spindle (13) that rotates the cutting tool (11a) and, based on the height position of the second surface (41b) calculated by the calculation unit (35), adjusts the height of the cutting tool (11a) to form a groove (44) on the second surface (41b).

[0104] In this embodiment, after adjusting the height of the cutting tool (11a) based on the height position of the second surface (41b) calculated by the calculation unit (35), the cutting tool (11a) forms a groove (44) on the second surface (41b), thus forming a groove (44) of the desired depth on the second surface (41b) of the object to be cut (4).

[0105] <10> A method for manufacturing a cut article (40) includes: a groove forming process, using the method described above. <1> to <9> The cutting device (1) described in any one of the following describes forming a groove (44) in the object to be cut (4); and a single-piece process, which cuts the object to be cut (4) with the groove (44) to single-piece into a plurality of cut pieces (40).

[0106] Using this embodiment, cut products (40) having a wettable side-type substrate (41) can be reliably manufactured.

[0107] Industrial availability

[0108] This invention can be applied to cutting devices and methods for manufacturing cut products.

[0109] Explanation of reference numerals in the attached figures

[0110] 1: Cutting device;

[0111] 4: Packaging substrate (object to be cut);

[0112] 11a: First cutting tool (cutting tool);

[0113] 13: Main spindle section;

[0114] 22: Workbench (cutting workbench);

[0115] 31: Filming location;

[0116] 31a: Camera (Filming Department);

[0117] 31b: Lens;

[0118] 31d: Captured image;

[0119] 32: High-level change mechanism;

[0120] 33: Light source;

[0121] 34: Shielding components;

[0122] 35: Arithmetic unit;

[0123] 36: Semi-reflective mirror (reflector);

[0124] 37: CCS Block (Baseline Block);

[0125] 40: Electronic components (cut parts);

[0126] 41: Substrate (d);

[0127] 41a: First page;

[0128] 41b: Second page;

[0129] 41c: Cross mark (cutting mark);

[0130] 42: Resin layer;

[0131] 44: Half-cut groove (groove).

Claims

1. A cutting apparatus wherein a groove is formed on a second surface of a cutting object opposite to the first surface, on a first surface of a plate-shaped lead frame having a resin layer formed thereon, the cutting apparatus comprising: The cutting worktable is capable of holding the object to be cut; A light source illuminates one side of the second surface of the object to be cut, which is placed on the cutting table. A shielding member is disposed along the path of the light propagating from the light source to the object being cut, and shields a portion of the light emitted from the light source; The imaging mechanism acquires an image of one side of the second face of the object being cut; A height-changing mechanism is available to change the height of the shooting mechanism; and The computing unit is capable of performing analysis and processing of the captured images. The shooting mechanism has the following features: A lens is positioned on the side of the object to be cut, closer to the object than the shielding member, along the path of the light, so that the light from the light source is focused onto the second surface; as well as The imaging unit is positioned on the opposite side of the cutting table relative to the object being cut, and can acquire the image by incident light reflected from the object being cut. The imaging unit acquires the captured images at multiple different heights changed by the height-changing mechanism. The calculation unit calculates the height position of the second surface based on the focus state of the occlusion member in the multiple captured images.

2. The cutting device according to claim 1, wherein, The shielding member is a frame that shields the outer edge region of the light emitted from the light source.

3. The cutting device according to claim 1 or 2, wherein, In each of the plurality of captured images, the computing unit calculates the contrast between the masking member and the portion adjacent to the masking member. The height position of the second surface is calculated based on the height of the capturing part when the captured image has the highest contrast among the calculated multiple contrast ratios.

4. The cutting device according to any one of claims 1 to 3, wherein, The shielding member is configured to move between the light source and the object to be cut.

5. The cutting device according to any one of claims 1 to 4, wherein, The heights of the light source and the shielding member are changed in conjunction with the height change of the shooting unit via the height changing mechanism.

6. The cutting apparatus according to any one of claims 1 to 5, further comprising: A reflector, positioned between the shielding member and the lens along the path of light, reflects the light toward the second surface. The height of the reflector is changed in conjunction with the height change of the imaging unit via the height changing mechanism.

7. The cutting device according to any one of claims 1 to 6, wherein, The imaging unit acquires the image of the cutting marks used when cutting the object into individual pieces.

8. The cutting device according to any one of claims 1 to 7, wherein, The imaging unit acquires a block image of a reference block, which serves as the reference height, for calculating the height position of the second surface.

9. The cutting apparatus according to any one of claims 1 to 8, further comprising: The cutting tool forms the groove on the second surface of the object being cut; and The spindle section rotates the cutting tool. Based on the height position of the second surface calculated by the calculation unit, after adjusting the height of the cutting tool, the cutting tool forms the groove on the second surface.

10. A method for manufacturing a cut article, comprising: The groove forming process involves forming the groove on the object to be cut using the cutting device as described in any one of claims 1 to 9. as well as The single-piece process involves cutting the object to be cut, which has the groove formed thereon, into multiple pieces.

Images