Inspection device and inspection method

Abstract

The invention relates to an inspection apparatus and an inspection method. The purpose of the present invention is to provide a technique capable of detecting an abnormality of a wire including a wire bonding portion at a high speed. An inspection device (100) is provided with: an imaging device (105) which is disposed above an aluminum conductor (1) and captures an image of the aluminum conductor (1) in order to acquire two-dimensional position information of the aluminum conductor (1); a coaxial illumination device (103) which is disposed coaxially with the imaging device (105) and which irradiates coaxial illumination light to the aluminum conductor (1); and a control device (301) that acquires, from the image, two-dimensional position information of a region that is present at the apex (3) of the aluminum conductor (1) and that is brighter than the surroundings, and a region that is present at the bonding site of the aluminum conductor (1) and that is brighter than the surroundings.

Description

Technical Field

[0001] The present invention relates to an inspection device and an inspection method. Background Art

[0002] Currently, techniques for inspecting abnormalities in wire bonding formed as wiring between electrodes have been widely proposed.

[0003] For example, Patent Document 1 discloses a method in which coaxial illumination is performed from above a wire, a photographing device disposed above the wire is moved in the height direction while photographing the wire, and the height position of the wire is measured based on the brightness distribution of bright spots at the vertex portion of the photographed wire.

[0004] In addition, for example, Patent Document 2 discloses a method in which coaxial illumination is performed from above a wire, bright spots at the vertex portion of the wire are detected, two-dimensional coordinates of the vertex portion are calculated, and the height of the calculated position is measured by a laser displacement meter.

[0005] Patent Document 1: Japanese Patent Laid-Open No. 7-63530

[0006] Patent Document 2: Japanese Patent Laid-Open No. 2010-62324

[0007] However, in the method described in Patent Document 1, the height position of the vertex portion of the wire can be measured, but abnormalities in the bonding portion of the wire, that is, the wire bonding portion, cannot be detected. In addition, even when measuring the height position of the vertex portion of the wire, in order to measure one wire, it is necessary to photograph a plurality of images while moving the photographing device in the height direction, and there is a problem that the measurement time is long when inspecting a plurality of wires.

[0008] Similarly, in the method described in Patent Document 2, the height position of the vertex portion of the wire can also be measured, but abnormalities in the bonding portion of the wire, that is, the wire bonding portion, cannot be detected. Summary of the Invention

[0009] Therefore, an object of the present invention is to provide a technique capable of detecting abnormalities in a wire including a wire bonding portion at high speed.

[0010] The inspection device according to the present invention detects abnormalities in a workpiece to be inspected after both ends thereof are wire-bonded to a portion to be joined of a semiconductor device by a wedge bonding method. The workpiece to be inspected is a wire having a diameter of 100 μm or more. The inspection device includes: an imaging device disposed above the wire for imaging the wire to obtain two-dimensional position information of the wire; a coaxial illumination coaxially disposed with the imaging device for irradiating the wire with coaxial illumination light; and a control device for obtaining, from the image, two-dimensional position information of a region where the brightness at the vertex of the wire is brighter than the surroundings and a region where the brightness at the bonding portion of the wire, i.e., the wire bonding portion, is brighter than the surroundings.

[0011] Effect of the Invention

[0012] According to the present invention, the inspection device can obtain two-dimensional position information of the vertex of the wire and the wire bonding portion by a single imaging. Therefore, it is possible to detect abnormalities in the wire including the wire bonding portion at high speed using the two-dimensional position information. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a side view of the inspection device according to Embodiment 1.

[0014] Figure 2 is a side view showing the bonding state of the workpiece to be inspected, i.e., an aluminum wire, and the bonding portion, i.e., the wire connection terminal portion and the electrode, in Embodiment 1.

[0015] Figure 3 is a view of an image obtained by imaging a semiconductor device from above by the imaging device included in the inspection device according to Embodiment 1.

[0016] Figure 4 is Figure 3 a view taken in the direction of A of

[0017] Figure 5 is a flowchart of the inspection method according to Embodiment 1.

[0018] Figure 6 is a side view of the inspection device according to Embodiment 2.

[0019] Figure 7 is a side view showing the state in which the workpiece to be inspected, i.e., an aluminum wire, floats in the inspection device according to Embodiment 2.

[0020] Figure 8 is a flowchart of the inspection method according to Embodiment 2.

[0021] Figure 9 is a side view of the inspection device according to Embodiment 3.

[0022] Figure 10 This is a side view showing the bonding state of the workpiece to be inspected, i.e., the aluminum wire, and the bonded portions, i.e., the wire connection terminal portion and the electrode, in Embodiment 4.

[0023] Figure 11 This is a top view showing the bonding state of the workpiece to be inspected, i.e., the aluminum wire, and the bonded portions, i.e., the wire connection terminal portion and the electrode, in Embodiment 4.

[0024] Figure 12 This is a flowchart of the inspection method according to Embodiment 4.

[0025] Figure 13 This is an explanatory diagram for explaining the inspection method according to Embodiment 4. Detailed Embodiment

[0026] <Embodiment 1>

[0027] Next, Embodiment 1 will be described with reference to the drawings. Figure 1 This is a side view of the inspection apparatus 100 according to Embodiment 1. Figure 2 This is a side view showing the bonding state of the aluminum wire 1, the wire connection terminal portion 4, and the electrode 6 in Embodiment 1.

[0028] In Figure 1 , the X direction, the Y direction, and the Z direction are orthogonal to each other. The X direction, the Y direction, and the Z direction shown in the following figures are also orthogonal to each other. Next, the direction including the X direction and the opposite direction of the X direction, i.e., the -X direction, will also be referred to as the "X-axis direction". In addition, next, the direction including the Y direction and the opposite direction of the Y direction, i.e., the -Y direction, will also be referred to as the "Y

[0029] axis direction". In addition, next, the direction including the Z direction and the opposite direction of the Z direction, i.e., the -Z direction, will also be referred to as the "Z-axis direction".

[0030] As Figure 1 shown, the inspection apparatus 100 detects abnormalities in the workpiece to be inspected after the two ends are wire-bonded to the bonded portion of the semiconductor device 10 by the wedge bonding method. The inspection apparatus 100 includes an inspection table 201, a motor 202, a ball screw 203, an imaging device 105, a coaxial illumination 103, and a control device 301.

[0031] On the upper surface (the surface in the Z direction) of the inspection table 201, the semiconductor device 10 including the workpiece to be inspected, i.e., the aluminum wire 1 (corresponding to the wire), is placed. In addition, in Figure 1A part of the semiconductor device 10 is shown. The inspection stage 201 is connected to the motor 202 and the ball screw 203, and can move in the X-axis direction by driving the motor 202. In addition, although not shown, the inspection stage 201 is also connected to the motor and the ball screw for Y-axis drive, and can also move in the Y-axis direction by driving the motor for Y-axis drive. Here, the inspection stage 201, the motor 202, and the ball screw 203 correspond to a moving mechanism that moves the semiconductor device 10 in two-dimensional directions (X-axis direction and Y-axis direction).

[0032] Next, the semiconductor device 10 will be described. As Figure 1 and Figure 2 shown, the semiconductor device 10 includes a substrate 5, an electrode 6, a semiconductor chip 7, and an aluminum wire 1 with a diameter greater than or equal to 100 μm. The semiconductor chip 7 is mounted on the upper surface (the surface in the Z direction) of the substrate 5 via solder 50. One end of the aluminum wire 1 is wire-bonded to the wire connection terminal portion 4 formed on the semiconductor chip 7 above (in the Z direction) by the wedge bonding method. The other end of the aluminum wire 1 is wire-bonded to the electrode 6 above (in the Z direction) by the wedge bonding method.

[0033] Here, the substrate 5 can be a metal substrate mainly made of copper or aluminum, etc., or a metal plate can be adhered to one or both sides of an insulator substrate. Similarly, the electrode 6 can also be a metal substrate mainly made of copper or aluminum, etc., or a metal plate can be adhered to one or both sides of an insulator substrate.

[0034] In the wedge bonding method, the aluminum wire 1 has a bonding portion, i.e., a wire bonding portion 2, with the bonded portion of the semiconductor device 10, and a vertex in the Z direction, i.e., a vertex portion 3. The bonded portion of the semiconductor device 10 refers to the wire connection terminal portion 4 of the semiconductor chip 7 or the electrode 6.

[0035] Returning to the description of the inspection device 100. As Figure 1 shown, the imaging device 105 is arranged above (in the Z direction) the aluminum wire 1. The imaging device 105 has an optical lens 104 that images the image of the semiconductor device 10 including the aluminum wire 1, and captures the image imaged through the optical lens 104 in order to obtain the two-dimensional position information of the aluminum wire 1. Here, the two-dimensional position information is the position information of two-dimensional coordinates (XY coordinates).

[0036] The coaxial illumination 103 is arranged between the aluminum wire 1 and the imaging device 105 and is arranged coaxially with the imaging device 105. The coaxial illumination 103 has a half mirror 102 and an illumination light source 101, and uses the half mirror 102 and the illumination light source 101 to vertically irradiate coaxial illumination light on the semiconductor device 10 including the aluminum wire 1 from above (in the Z direction).

[0037] The control device 301 acquires the images captured by the imaging device 105 and appropriately performs arithmetic processing. More specifically, the control device 301 performs arithmetic processing to obtain two-dimensional position information of regions that are brighter than the surroundings at the vertex portion 3 of the aluminum wire 1 and regions that are brighter than the surroundings at the bonding portion of the aluminum wire 1, i.e., the wire bonding portion 2, from the images. In addition, the control device 301 controls each part of the inspection device 100. Furthermore, the inspection device 100 may separately include a control device that controls each part of the inspection device 100 from the control device 301.

[0038] The control device 301 includes a processor (not shown) and a memory (not shown). The above functions of the control device 301 are described as a program, and the processor executes this program, thereby implementing the functions of the control device 301.

[0039] As Figure 1 shown, in the case of performing wire bonding by the wedge bonding method using an aluminum wire 1 having a diameter greater than or equal to 100 μm, ultrasonic bonding is performed while pressing from above (Z direction) in a state where the aluminum wire 1 is laid flat. Therefore, a state is formed in which a flat region exists on the surface (the surface in the Z direction) of the wire bonding portion 2.

[0040] If the coaxial illumination light (hereinafter, also simply referred to as "illumination light") irradiated by the coaxial illumination 103 irradiates the aluminum wire 1, there are portions perpendicular to the irradiation direction of the illumination light on the surfaces (the surfaces in the Z direction) of the vertex portion 3 and the wire bonding portion 2. Therefore, the light is reflected in the direction opposite to the irradiation direction, i.e., in the direction toward the imaging device 105. Therefore, if the aluminum wire 1 is imaged by the imaging device 105, the overall brightness of the aluminum wire 1 becomes darker, and the vertex portion 3 and the wire bonding portion 2 are observed as regions that are brighter than the surroundings in this dark region.

[0041] On the other hand, in the case of performing wire bonding using an aluminum wire 1 having a diameter less than 100 μm, there are many deformed portions on the surface (the surface in the Z direction) of the aluminum wire 1. Therefore, there are few regions perpendicular to the irradiation direction of the light, and accordingly, the bright regions become narrower. Therefore, it is difficult to detect the wire bonding portion 2 through the image. Therefore, it is preferable that the diameter of the aluminum wire 1 is greater than or equal to 100 μm.

[0042] Figure 3 FIG. is an image obtained by imaging the semiconductor device 10 from above (Z direction) by the imaging device 105 included in the inspection device 100 according to Embodiment 1.

[0043] As Figure 3As shown, two aluminum wires 1a and 1b are arranged on the upper surface (the surface in the Z direction) of the substrate 5. The aluminum wire 1a has wire bonding portions 2 at both ends where wire bonding is performed by the wedge bonding method, and both ends of the aluminum wire 1a are joined to the wire connection terminal portion 4a and the electrode 6a respectively.

[0044] Similarly to the aluminum wire 1a, the aluminum wire 1b also has wire bonding portions 2 at both ends where wire bonding is performed by the wedge bonding method, and both ends of the aluminum wire 1b are joined to the wire connection terminal portion 4b and the electrode 6b respectively. After wire bonding of the aluminum wire 1b, it is subjected to an external force, and the loop portion of the aluminum wire 1b falls down.

[0045] Illumination light is irradiated vertically from directly above (in the Z direction) of the aluminum wires 1a and 1b by the coaxial illumination 103. Therefore, the vertex portions 3 and the wire bonding portions 2 of the two aluminum wires 1a and 1b are observed as bright regions in the captured image. On the other hand, since there is almost no horizontal region in the whole of the aluminum wires 1a and 1b, the whole except for the vertex portions 3 and the wire bonding portions 2 is observed as a dark region.

[0046] Generally, when connecting two points by an aluminum wire, in the case where the aluminum wire is in a straight shape like the aluminum wire 1a, the wire bonding portion 2 and the vertex portion 3 are in a positional relationship arranged in a straight line. On the other hand, in the case where an external force is applied as in the aluminum wire 1b and the loop portion falls down, the wire bonding portion 2 and the vertex portion 3 are not arranged in a straight line, and a positional relationship is formed in which the position of the vertex portion 3 is offset with respect to the straight line connecting between the two wire bonding portions 2.

[0047] Figure 4 is Figure 3 View A. Here, for the sake of convenience of explanation, the illustration of the electrodes 6a and 6b is omitted.

[0048] As Figure 4 shown, it can be seen that the aluminum wire 1a vertically forms a loop from the wire bonding portion 2 to the vertex portion 3. In contrast, the aluminum wire 1b forms it obliquely from the wire bonding portion 2 to the vertex portion 3, that is, it has a shape in which the loop falls down obliquely.

[0049] In addition, in the case where the aluminum wire falls down obliquely, as Figure 3 and Figure 4 shown, the distance between the vertex portion 3 of the aluminum wire 1a and the vertex portion 3 of the aluminum wire 1b becomes shorter. Therefore, by measuring the two-dimensional distance of the bright regions existing at the vertex portion 3 of the aluminum wire 1a and the vertex portion 3 of the aluminum wire 1b, the approach between the aluminum wire 1a and the aluminum wire 1b can be detected. Since inspection can be performed from a wide-range image captured by the imaging device 105, inspection can be concentrated on a plurality of aluminum wires 1a and 1b in a short time.

[0050] Next, the inspection method related to Embodiment 1 will be described. Figure 5 It is a flowchart of the inspection method related to Embodiment 1.

[0051] As Figure 5 shown, first, the control device 301 positions the inspection table 201 at a determined position (step S1), and the aluminum wire 1 is photographed by the photographing device 105 (step S2). The control device 301 obtains two-dimensional position information of the bright regions existing at the wire bonding portion 2 and the bright regions existing at the vertex portion 3 from the image photographed by the photographing device 105 (step S3).

[0052] Next, the control device 301 compares the obtained two-dimensional position information with the two-dimensional position information preset in the memory of the control device 301. If there is a difference greater than or equal to a certain value, it is determined that there is an abnormality in the wire deformation or the bonding position (step S4).

[0053] Here, the determination method related to the wire deformation or the abnormality of the bonding position will be described in detail. The control device 301 calculates the centroids of the bright regions existing at the wire bonding portion 2 and the centroids of the bright regions existing at the vertex portion 3 based on the obtained image, and calculates the two-dimensional distance between the two centroids. The control device 301 compares the calculated two-dimensional distance with the two-dimensional distance between the wire bonding portion 2 and the vertex portion 3 preset in the memory of the control device 301. If there is a difference greater than or equal to a certain value, it is determined that there is an abnormality in the wire deformation or the bonding position.

[0054] Alternatively, the bright regions existing at the wire bonding portion 2 and the vertex portion 3 can be surrounded by rectangles with the smallest areas, and the centers of the rectangles are set as the wire bonding portion 2 and the vertex portion 3 respectively, and the two-dimensional distance between the two is compared with the two-dimensional distance between the wire bonding portion 2 and the vertex portion 3 preset in the memory of the control device 301.

[0055] Alternatively, the distance between the closest pixels of the bright regions existing at the wire bonding portion 2 and the vertex portion 3 can be compared with the two-dimensional distance between the wire bonding portion 2 and the vertex portion 3 preset in the memory of the control device 301.

[0056] As described above, the inspection device 100 according to Embodiment 1 includes: an imaging device 105 disposed above the aluminum wire 1 (in the Z direction) for imaging the aluminum wire 1 to obtain two-dimensional position information of the aluminum wire 1; a coaxial illumination 103 coaxially disposed with the imaging device 105 for irradiating the aluminum wire 1 with coaxial illumination light; and a control device 301 for obtaining two-dimensional position information of regions where the brightness is brighter than the surroundings at the vertex portion 3 of the aluminum wire 1 and at the bonding portion of the aluminum wire 1, i.e., the wire bonding portion 2, from the image.

[0057] Specifically, the control device 301 compares the two-dimensional position information of the regions where the brightness is brighter than the surroundings at the vertex portion 3 and at the wire bonding portion 2 obtained from the image with the two-dimensional position information of the vertex portion 3 and the wire bonding portion 2 set in advance, and determines that there is an abnormality in the wire deformation or the bonding position when the difference is greater than or equal to a certain value.

[0058] Therefore, the inspection device 100 can obtain the two-dimensional position information of the vertex portion 3 and the wire bonding portion 2 of the aluminum wire 1 by one imaging, and thus can use the two-dimensional position information to detect the abnormality of the aluminum wire 1 including the wire bonding portion 2 at high speed.

[0059] In addition, as Figure 3 and Figure 4 shown, the control device 301 obtains two-dimensional position information of regions where the brightness is brighter than the surroundings at the vertex portions 3 of the plurality of aluminum wires 1a, 1b from the image, measures the distances between the plurality of vertex portions 3 of the plurality of aluminum wires 1a, 1b according to the obtained two-dimensional position information, and compares the measured distances between the vertex portions 3 with the distances between the plurality of vertex portions 3 set in advance, thereby being able to detect the approach between the aluminum wire 1a and the aluminum wire 1b. Thus, the possibility of contact between adjacent aluminum wires 1a, 1b can be detected. In addition, when inspecting a plurality of aluminum wires 1a, 1b, since the inspection can be performed based on a wide-range image captured by the imaging device 105, the inspection of the plurality of aluminum wires 1a, 1b can be concentrated and performed in a short time.

[0060] <Modification Example of Embodiment 1>

[0061] In addition to aluminum, the aluminum wire 1 may be a fine metal wire made mainly of copper, gold, silver, etc. that can be wire-bonded by the wedge bonding method.

[0062] In addition, the position of the captured image is determined by moving the inspection stage 201 in two-dimensional directions. However, the structure may also be such that the imaging device 105 and the coaxial illumination 103 move in two-dimensional directions, and the imaging position is determined by moving the imaging device 105 and the coaxial illumination 103 in two-dimensional directions.

[0063] In addition, the inspection stage 201 is configured to be movable by the motor 202 and the ball screw 203, but the structure using a linear motor may also be employed.

[0064] In addition, in order to adjust the focus of the imaging device 105, the inspection stage 201 may be configured to move in the height direction (Z-axis direction), or the imaging device 105 may be configured to move in the height direction (Z-axis direction).

[0065] In addition, one end of the aluminum wire 1 is joined to the wire connection terminal portion 4 above (in the Z direction) the semiconductor chip 7, and the other end is joined to the electrode 6. However, the joined portion of the semiconductor device 10 is not limited thereto, and any material that can be wire-bonded by the wedge bonding method may be used.

[0066] <Embodiment 2>

[0067] Next, the inspection device 100 according to Embodiment 2 will be described. Figure 6 FIG. is a side view of the inspection device 100 according to Embodiment 2. In addition, in Embodiment 2, the same reference numerals are given to the structural elements that are the same as those described in Embodiment 1, and the description thereof is omitted.

[0068] In Embodiment 2, the inspection device 100 has, in addition to the structure of Embodiment 1, as Figure 6 shown, a laser displacement meter 302. The laser displacement meter 302 is disposed above (in the Z direction) the aluminum wire 1.

[0069] The control device 301 (see Figure 1 ) moves the inspection stage 201 in two-dimensional directions with respect to the position of the two-dimensional coordinates of the detected wire bonding portion 2 so that the wire bonding portion 2 is irradiated with the laser 303 emitted from the laser displacement meter 302. Information on the height position of the wire bonding portion 2 is obtained by this operation. In addition, in Figure 6 , the laser displacement meter 302 measures the position of the wire bonding portion 2 above (in the Z direction) the wire connection terminal portion 4, but the position of the wire bonding portion 2 above (in the Z direction) the electrode 6 can also be measured in the same manner.

[0070] Figure 7 FIG. is a side view showing a state in which the aluminum wire 1 floats in the inspection device 100 according to Embodiment 2. AsFigure 7 As shown, one end side (-X side) of the wire bonding portion 2 of the aluminum wire 1 is slightly lifted from the wire connection terminal portion 4. The amount of lift is, for example, greater than or equal to 10 μm to about several tens of μm. If it becomes such a state, it is difficult to determine whether the wire bonding portion 2 is in a lifted state when observing only from above (Z direction).

[0071] As a reason for such a state, it is considered that the surface (Z-direction surface) of the wire connection terminal portion 4 is contaminated during wire bonding, or wire bonding is performed with a foreign object sandwiched therebetween. As a result, the aluminum wire 1 and the wire connection terminal portion 4 are not physically joined or peeled off after wire bonding, etc., and the wire bonding portion 2 and the wire connection terminal portion 4 are slightly separated and lifted.

[0072] As described above, the height position of the wire bonding portion 2 in the state where the wire bonding portion 2 is lifted is higher than the height position in the case where wire bonding is normally performed. Therefore, by measuring the height position of the wire bonding portion 2 using the laser displacement meter 302, it is possible to detect an abnormality in the bonding between the aluminum wire 1 and the wire connection terminal portion 4.

[0073] In addition, if set in absolute coordinates, the reference of the height position of the wire bonding portion 2 is affected by the tilt of the inspection table 201, the thickness fluctuation of the substrate 5, and the warpage of the substrate 5. Therefore, it is preferable to use the height position of the surface (Z-direction surface) of the wire connection terminal portion 4 as close as possible to the wire bonding portion 2 as a reference.

[0074] In addition, although not shown, in the case where the laser displacement meter 302 measures the distance of the position irradiated with the laser 303 by triangulation, it sometimes measures multiple reflections from the surrounding metal surfaces, and the possibility of mismeasurement is high. Therefore, it is preferable to use a confocal method type laser displacement meter that measures the distance according to the color (wavelength) of the reflected light.

[0075] In addition, the laser 303 of the laser displacement meter 302 can be of a type that has a spot shape and measures a local point, or can be of a type that has a linear shape and measures the height position in a linear region.

[0076] Next, the inspection method according to Embodiment 2 will be described. Figure 8 It is a flowchart of the inspection method according to Embodiment 2.

[0077] As Figure 8As shown, first, the control device 301 positions the inspection table 201 at the determined position (step S11), and the aluminum wire 1 is photographed by the photographing device 105 (step S12). The control device 301 obtains two-dimensional position information of the bright regions existing at the wire bonding portion 2 and the bright regions existing at the vertex portion 3 from the image photographed by the photographing device 105 (step S13).

[0078] The control device 301 positions the laser displacement meter 302 so that the laser 303 of the laser displacement meter 302 irradiates the position of the obtained two-dimensional position information of the wire bonding portion 2 (step S14). Specifically, the control device 301 positions the laser displacement meter 302 by moving the inspection table 201 in the two-dimensional direction.

[0079] Next, the laser displacement meter 302 irradiates the laser 303 to the bright region existing at the wire bonding portion 2 and measures the height position of the wire bonding portion 2 (step S15).

[0080] Next, the control device 301 determines the floating of the wire bonding portion 2 (step S16). Specifically, the control device 301 compares the measured height position of the wire bonding portion 2 with the height position of the wire bonding portion 2 preset in the memory of the control device 301. If the comparison result is within the specified range, it is determined that the wire bonding portion 2 does not float and is normal. If the comparison result is outside the specified range, it is determined that the wire bonding portion 2 has floating and is abnormal.

[0081] As described above, the inspection device 100 according to the second embodiment further includes: a laser displacement meter 302 disposed above the aluminum wire 1 (in the Z direction) to measure the height position of the aluminum wire 1; and a moving mechanism that moves the semiconductor device 10 in the two-dimensional direction. The moving mechanism moves the semiconductor device 10 so that the laser displacement meter 302 is located above the wire bonding portion 2 (in the Z direction), and the laser displacement meter 302 irradiates the laser 303 to the region where the brightness of the wire bonding portion 2 is brighter than the surroundings to measure the height position of the wire bonding portion 2.

[0082] Therefore, it is possible to detect the floating of the wire bonding portion 2 that is difficult to determine only by observing the appearance.

[0083] <Modification Example of Embodiment 2>

[0084] In Embodiment 2, the inspection table 201 is moved in two-dimensional directions to position the laser displacement meter 302. However, the laser displacement meter 302 may be configured to be movable in two-dimensional directions, and its own positioning may be performed by moving the laser displacement meter 302 in two-dimensional directions. In addition, in order to adjust the measurement distance of the laser displacement meter 302, the inspection table 201 may be configured to be movable in the height direction (Z-axis direction), or the laser displacement meter 302 may be configured to be movable in the height direction (Z-axis direction).

[0085] <Embodiment 3>

[0086] Next, the inspection device 100 according to Embodiment 3 will be described. Figure 9 It is a side view of the inspection device 100 according to Embodiment 3. In addition, in Embodiment 3, the same reference numerals are assigned to the structural elements that are the same as those described in Embodiments 1 and 2, and the description thereof is omitted.

[0087] In Embodiment 3, the inspection device 100 has, in addition to the structure of Embodiment 2, as Figure 9 shown, a laser displacement meter 312. That is, the inspection device 100 has two laser displacement meters 302 and 312. The two laser displacement meters 302 and 312 are arranged and disposed in the X-axis direction. The laser displacement meter 302 is disposed above the aluminum wire 1 (in the Z direction), and the laser displacement meter 312 is disposed above a portion of the semiconductor device 10 near the wire bonding portion 2 (in the Z direction). The portion of the semiconductor device 10 near the wire bonding portion 2 refers to the electrode 6, the semiconductor chip 7, or the substrate 5 of the semiconductor device 10. In addition, in Figure 9 the laser displacement meter 312 is disposed above the semiconductor chip 7 (in the Z direction).

[0088] By moving the inspection table 201 in two-dimensional directions with respect to the position of the two-dimensional coordinates of the wire bonding portion 2 detected by the coaxial illumination 103, positioning is performed such that the wire bonding portion 2 is irradiated with the laser 303 emitted from the laser displacement meter 302.

[0089] At the same time, the laser 313 emitted from the laser displacement meter 312 irradiates the surface of the semiconductor chip 7, which is a portion of the semiconductor device 10 near the wire bonding portion 2, and it is possible to simultaneously measure the height position of the wire bonding portion 2 and the height position of the semiconductor chip 7 near it.

[0090] In addition, the inspection method according to Embodiment 3 is the same as that of Embodiment 2 except that the wire bonding portion 2 and the portion of the semiconductor device 10 near the wire bonding portion 2 are measured simultaneously, and thus the description thereof is omitted.

[0091] In Embodiment 2, in order to measure the height position of the wire bonding portion 2 and the height position of the portion of the semiconductor device 10 near the wire bonding portion 2 that serves as a reference height position, it is necessary to move the inspection stage 201.

[0092] In contrast, the inspection device 100 according to Embodiment 3 includes laser displacement meters 302 and 312. For the two laser displacement meters 302 and 312, the laser 303 of one laser displacement meter 302 is irradiated onto the region where the brightness of the wire bonding portion 2 is brighter than the surroundings to measure the height position of the wire bonding portion 2. At the same time, the laser 313 of the other laser displacement meter 312 is irradiated onto the portion of the semiconductor device 10 near the wire bonding portion 2 to measure the height position of the bonded portion. Thus, the difference between the height position of the wire bonding portion 2 and the height position of the portion of the semiconductor device 10 is measured.

[0093] Therefore, it is possible to measure the height position of the wire bonding portion 2 and the reference height position simultaneously without moving the inspection stage 201. As a result, the inspection time for the floating of the wire bonding portion 2 can be shortened.

[0094] <Modification Example of Embodiment 3>

[0095] In Embodiment 3, the inspection stage 201 is moved in the two-dimensional direction to position the laser displacement meters 302 and 312. However, the laser displacement meters 302 and 312 may be configured to be movable in the two-dimensional direction, and the laser displacement meters 302 and 312 may be positioned by moving them in the two-dimensional direction. In addition, in order to adjust the measurement distance of the laser displacement meters 302 and 312, the inspection stage 201 may be configured to be movable in the height direction (Z-axis direction), or the laser displacement meters 302 and 312 may be configured to be movable in the height direction (Z-axis direction).

[0096] <Embodiment 4>

[0097] Next, the inspection device 100 according to Embodiment 4 will be described. Figure 10 It is a side view showing the bonding state of the aluminum wire 1 with the wire connection terminal portion 4 and the electrode 6 in Embodiment 4. Figure 11 It is a top view showing the bonding state of the aluminum wire 1 with the wire connection terminal portion 4 and the electrode 6 in Embodiment 4. In addition, in Embodiment 4, the same reference numerals are given to the structural elements that are the same as those described in Embodiments 1 to 3, and the description thereof is omitted.

[0098] In Embodiment 1, the two-dimensional position information of the region where the brightness at the vertex portion 3 is brighter than the surroundings and the region where the brightness at the wire bonding portion 2 is brighter than the surroundings is compared with the two-dimensional position information of the vertex portion 3 and the wire bonding portion 2 preset in the memory of the control device 301. When there is a difference greater than or equal to a certain value, it is determined that there is an abnormality in the wire deformation or the bonding position.

[0099] In contrast, in Embodiment 4, for the purpose of performing inspection with higher accuracy compared to the case of Embodiment 1 and accurately grasping the overall shape of the aluminum wire 1. The structure of the inspection device 100 according to Embodiment 4 is the same as that in the case of Embodiment 1.

[0100] The necessity of accurately grasping the overall shape of the aluminum wire 1 will be described. As Figure 10 shown, a semiconductor chip 7 is mounted on the upper surface (the surface in the Z direction) of the substrate 5 via solder 50. One end of the aluminum wire 1 is wire-bonded to the wire connection terminal portion 4 formed on the semiconductor chip 7 (in the Z direction) by the wedge bonding method. The other end of the aluminum wire 1 is wire-bonded to the electrode 6 (in the Z direction) by the wedge bonding method.

[0101] As Figure 11 shown, similar to the Figure 3 case, the wire bonding portion 2 and the vertex portion 3 reflect the illumination light emitted from the coaxial illumination 103 (refer to Figure 1 ), so there are bright regions in the dark regions, and the two-dimensional position information of each can be measured from the image.

[0102] Regarding the entire aluminum wire 1, similar to the Figure 3 case, it is observed as a region with a dark overall brightness from the image. However, regarding the solder 50 that overflows to the periphery of the semiconductor chip 7 and the contour 51 of the three-dimensional object, they are also observed as dark regions from the image, and it is difficult to grasp the overall shape of the aluminum wire 1 only by the degree of brightness. Here, the three-dimensional object refers to the substrate 5 and the electrode 6.

[0103] Therefore, in Embodiment 4, the overall shape of the aluminum wire 1 is grasped by tracing the dark region that continues from the region where the brightness at both ends of the aluminum wire 1 is brighter than the surroundings, that is, the wire bonding portion 2, to the region where the brightness at the vertex portion 3 is brighter than the surroundings.

[0104] For example, the dark region existing in the solder 50 extends in the arrow directions of C and D in Figure 11 , but there is no vertex portion 3 at the front end of this dark region. On the other hand, the dark region is in Figure 11extends in the arrow direction of B, but there is a vertex portion 3 at the front end of the dark - luminance region. Additionally, for example, in Figure 11 the arrow directions of F and G, the contour 51 of the electrode 6 becomes a dark - luminance region due to the shadow of illumination, but there is no vertex portion 3 at the front end of this dark - luminance region. On the other hand, there is a vertex portion 3 at the front end in the arrow direction of E.

[0105] In this way, when tracing the dark - luminance region starting from the bright - luminance region existing in the wire bonding portion 2, if there is a vertex portion 3 at the front end of the dark - luminance region, it is determined that the dark - luminance region is the aluminum wire 1; if there is no vertex portion 3 at the front end of the dark - luminance region, it is determined that the dark - luminance region is not the aluminum wire 1. Through these determinations, the overall shape of the accurate aluminum wire 1 can be grasped.

[0106] Next, the inspection method according to Embodiment 4 will be described. Figure 12 is a flowchart of the inspection method according to Embodiment 4.

[0107] As Figure 12 shown, first, the control device 301 positions the inspection table 201 at a determined position (step S21), and the aluminum wire 1 is photographed by the photographing device 105 (step S22). The control device 301 obtains the two - dimensional position information of the bright - luminance region existing at the wire bonding portion 2 and the bright - luminance region existing at the vertex portion 3 from the image photographed by the photographing device 105 (step S23).

[0108] The control device 301 traces the dark - luminance region in the image from the position of the wire bonding portion 2 towards the position of the vertex portion 3 (step S24). If there is a vertex portion 3 at the front end of the trace (Yes in step S25), the control device 301 determines that the traced dark - luminance region is the aluminum wire 1.

[0109] On the other hand, if there is no vertex portion 3 at the front end of the trace and the dark - luminance region is interrupted (No in step S25), the control device 301 determines that the traced dark - luminance region is not the aluminum wire 1.

[0110] Finally, the control device 301 determines whether there is wire deformation based on the shape of the dark - luminance region determined to be the aluminum wire 1 (step S26). The control device 301, for example, compares the obtained shape of the aluminum wire 1 with the shape of the aluminum wire 1 preset in the memory of the control device 301. If there is a difference greater than or equal to a certain value, it is determined that there is wire deformation; if there is no difference greater than or equal to a certain value, it is determined that there is no wire deformation.

[0111] In Embodiment 1, the presence or absence of wire deformation was determined for the shape of the aluminum wire 1 using only the two-dimensional position information of the wire bonding part 2 and the vertex part 3. However, in Embodiment 4, by accurately grasping the shape of the part of the aluminum wire 1 other than the wire bonding part 2 and the vertex part 3, the wire deformation can be determined with higher accuracy.

[0112] Here, details of the method for tracking the dark region performed by the control device 301 in step S24 will be described. Figure 13 It is an explanatory diagram for explaining the inspection method according to Embodiment 4.

[0113] The control device 301 obtains the luminance data of the pixels in addition to the two-dimensional coordinate information from the image. The image includes numerical data of luminance in the number of pixels of the number of vertical pixels × the number of horizontal pixels. The smaller the value of the luminance data, the darker the luminance, and the larger the value, the brighter the luminance. For example, in the 8-bit luminance data, the luminance of each pixel is represented by a value from 0 to 255.

[0114] When the control device 301 has obtained Figure 11 the image shown, a straight line extending from the wire bonding part 2 to the vertex part 3 is calculated. If the origin is the wire bonding part 2 and it overlaps with Figure 11 the image, it is as shown in Figure 13 . With the pixels overlapping the obtained straight line (y = ax) as a reference, the shape of the aluminum wire 1 is retrieved within the range of -Δ to +Δ in the Y-axis direction preset in the Y-axis direction (within the frame of Figure 13 ).

[0115] First, the control device 301 starts from the origin (wire bonding part 2) at the left end and first searches for the upper side of the aluminum wire 1. In the upper side search, the luminance change is investigated in the -Y direction within the range of the frame starting from the position of +Δ in the Y-axis direction of the origin. When investigating the luminance change in the upper side search direction, if a point where the luminance changes by an amount greater than or equal to a preset luminance is found at a point where the luminance changes from white to black, that point is determined as the position of the upper side of the aluminum wire 1.

[0116] Next, the control device 301 performs a search for the lower side of the aluminum wire 1. In the lower side search, the luminance change is investigated in the Y direction within the range of the frame starting from the position of -Δ in the Y-axis direction of the origin. When investigating the luminance change in the lower side search direction, if a point where the luminance changes by an amount greater than or equal to a preset luminance is found at a point where the luminance changes from white to black, that point is determined as the position of the lower side of the aluminum wire 1.

[0117] Calculate the distance between the point determined to be at the upper position of the aluminum wire 1 and the point determined to be at the lower position. If it falls within the range of the thickness of the aluminum wire 1 preset in the memory of the control device 301, it is determined that the upper and lower sides of the detected aluminum wire 1 are correctly detected.

[0118] Repeat these processes between the wire bonding portion 2 and the vertex portion 3. The upper and lower sides of the detected aluminum wire 1 represent the shape of the aluminum wire 1. If the distance between the upper and lower sides of the aluminum wire 1 falls outside the range of the thickness of the aluminum wire 1 preset in the memory of the control device 301, it is regarded as data loss.

[0119] As described above, in the inspection device according to the fourth embodiment, the control device 301 detects the two-dimensional shape of the aluminum wire 1 by tracking the region where the brightness is darker than the surroundings from the position of the wire bonding portion 2 to the position of the vertex portion 3 in the image.

[0120] Therefore, the overall shape of the aluminum wire 1 can be accurately grasped, and thus the inspection accuracy regarding the deformation of the aluminum wire 1 is improved compared with the case of the first embodiment.

[0121] In addition, the respective embodiments can be freely combined, and the respective embodiments can be appropriately deformed and omitted.

[0122] Hereinafter, the aspects of the present invention will be summarized and described as appended notes.

[0123] (Appended Note 1)

[0124] An inspection device that detects an abnormality of a workpiece after both ends are wire-bonded to a bonded portion of a semiconductor device by a wedge bonding method,

[0125] wherein the workpiece to be inspected is a wire having a diameter greater than or equal to 100 μm,

[0126] The inspection device includes: a photographing device that is disposed above the wire and photographs an image of the wire in order to obtain two-dimensional position information of the wire;

[0127] Coaxial illumination that is coaxially disposed with the photographing device and irradiates coaxial illumination light to the wire; and

[0128] A control device that obtains the two-dimensional position information of the region where the brightness is brighter than the surroundings at the vertex portion of the wire and the region where the brightness is brighter than the surroundings at the bonding portion of the wire, that is, the wire bonding portion, from the image.

[0129] (Appended Note 2)

[0130] The inspection device according to Appended Note 1, wherein,

[0131] The control device compares the two-dimensional position information of the regions where the brightness is brighter than the surroundings at the vertex portion and the wire bonding portion with the two-dimensional position information of the vertex portion and the wire bonding portion set in advance, and determines that there is an abnormality in the wire deformation or the bonding position when there is a difference greater than or equal to a certain value.

[0132] (Supplementary Note 3)

[0133] The inspection device according to Supplementary Note 1 further includes:

[0134] A laser displacement meter, which is arranged above the wire to measure the height position of the wire; and

[0135] A moving mechanism, which moves the semiconductor device in a two-dimensional direction,

[0136] The moving mechanism moves the semiconductor device in such a way that the laser displacement meter is located above the wire bonding portion,

[0137] The laser displacement meter irradiates the region where the brightness is brighter than the surroundings at the wire bonding portion with laser to measure the height position of the wire bonding portion.

[0138] (Supplementary Note 4)

[0139] The inspection device according to Supplementary Note 3, wherein,

[0140] There are two laser displacement meters,

[0141] For the two laser displacement meters, the laser of one laser displacement meter irradiates the region where the brightness is brighter than the surroundings at the wire bonding portion to measure the height position of the wire bonding portion. At the same time, the laser of the other laser displacement meter irradiates the part of the semiconductor device near the wire bonding portion to measure the height position of the part of the semiconductor device, thereby measuring the difference between the height position of the wire bonding portion and the height position of the part of the semiconductor device.

[0142] (Supplementary Note 5)

[0143] The inspection device according to Supplementary Note 1, wherein,

[0144] The workpiece to be inspected is a plurality of wires with a diameter greater than or equal to 100 μm,

[0145] The control device obtains two-dimensional position information of an area where the brightness is brighter than the surroundings at the vertex portions of the plurality of wires from the image, measures the distances between the plurality of vertex portions of the plurality of wires according to the obtained two-dimensional position information, and compares the measured distances between the vertex portions with the distances between the plurality of vertex portions set in advance.

[0146] (Supplementary Note 6)

[0147] The inspection device according to Supplementary Note 1, wherein

[0148] The control device detects the two-dimensional shape of the wire by tracing an area where the brightness is darker than the surroundings from the position of the wire bonding portion to the position of the vertex portion in the image.

[0149] (Supplementary Note 7)

[0150] An inspection method for detecting an abnormality of a workpiece to be inspected after both ends are wire-bonded to a joint portion of a semiconductor device by a wedge bonding method,

[0151] wherein the workpiece to be inspected is a wire having a diameter greater than or equal to 100 μm,

[0152] This inspection method has the following steps:

[0153] In order to obtain two-dimensional position information of the wire, an image of the wire is taken from above the wire by an imaging device;

[0154] Coaxial illumination light is irradiated to the wire coaxially with the imaging device; and

[0155] Two-dimensional position information of an area where the brightness is brighter than the surroundings at the vertex portion of the wire and an area where the brightness is brighter than the surroundings at the bonding portion of the wire, i.e., the wire bonding portion, is obtained from the image.

[0156] (Supplementary Note 8)

[0157] The inspection method according to Supplementary Note 7, wherein

[0158] After the step of obtaining the two-dimensional position information, the two-dimensional position information of the area where the brightness is brighter than the surroundings at the vertex portion and the area where the brightness is brighter than the surroundings at the wire bonding portion obtained is compared with the two-dimensional position information of the vertex portion and the wire bonding portion set in advance, and when there is a difference greater than or equal to a certain value, it is determined that there is an abnormality in the wire deformation or the bonding position.

[0159] (Supplementary Note 9)

[0160] The inspection method according to Note 7, wherein,

[0161] After the process of obtaining the two-dimensional position information, there is also the following process:

[0162] Measuring the height position of the wire from above the wire by a laser displacement meter; and

[0163] Moving the semiconductor device in two-dimensional directions,

[0164] In the process of moving the semiconductor device in two-dimensional directions, moving the semiconductor device in such a manner that the laser displacement meter is located above the wire bonding portion,

[0165] In the process of measuring the height position of the wire, irradiating the laser to the region where the brightness is brighter than the surrounding area existing in the wire bonding portion, and measuring the height position of the wire bonding portion.

[0166] (Note 10)

[0167] The inspection method according to Note 9, wherein,

[0168] The process of measuring the height position of the wire is implemented by two of the laser displacement meters,

[0169] Regarding the two laser displacement meters, irradiating the laser of one of the laser displacement meters to the region where the brightness is brighter than the surrounding area existing in the wire bonding portion, and measuring the height position of the wire bonding portion. At the same time, irradiating the laser of the other laser displacement meter to the portion of the semiconductor device near the wire bonding portion, and measuring the height position of the portion of the semiconductor device, thereby measuring the difference in height position between the wire bonding portion and the portion of the semiconductor device.

[0170] (Note 11)

[0171] The inspection method according to Note 7, wherein,

[0172] The workpiece to be inspected is a plurality of wires with a diameter greater than or equal to 100 μm,

[0173] In the process of obtaining the two-dimensional position information, obtaining the two-dimensional position information of the region where the brightness is brighter than the surrounding area existing at the vertex portions of the plurality of wires from the image, measuring the distance between the plurality of vertex portions of the plurality of wires according to the obtained two-dimensional position information, and comparing the measured distance between the vertex portions with the distance between the plurality of vertex portions preset in advance.

[0174] (Supplementary Note 12)

[0175] The inspection method according to Supplementary Note 7, wherein,

[0176] After the step of obtaining the two-dimensional position information, there is also the following step: detecting the two-dimensional shape of the wire by tracking the region darker than the surrounding in terms of brightness from the position of the wire bonding part to the position of the vertex part in the image.

[0177] Description of reference numerals

[0178] 1, 1a, 1b Aluminum wires, 2 Wire bonding part, 3 Vertex part, 4, 4a, 4b Wire connection terminal parts, 6, 6a, 6b Electrodes, 10 Semiconductor device, 100 Inspection device, 103 Coaxial illumination, 105 Imaging device, 201 Inspection table, 202 Motor, 203 Ball screw, 301 Control device, 302 Laser displacement meter.

Claims

1. An inspection device for detecting abnormality of an inspection workpiece after both ends are wire-bonded to a joining portion of a semiconductor device by a wedge bonding method, in, The workpiece to be inspected is a wire with a diameter greater than or equal to 100 μm, The inspection device comprises: a photographing device, which is arranged above the conductor and photographs an image of the conductor in order to obtain two-dimensional position information of the conductor; Coaxial lighting, which is coaxially arranged with the photographing device and irradiates the wire with coaxial lighting light; as well as A control device acquires the two-dimensional position information of a region brighter than surroundings at a vertex of the wire and a region brighter than surroundings at a wire bonding portion which is a joining portion of the wire from the image.

2. The inspection device according to claim 1, wherein: The control device compares the obtained two-dimensional position information of the area at the vertex portion whose brightness is brighter than the surrounding area and the area at the wire bonding portion whose brightness is brighter than the surrounding area with the pre-set two-dimensional position information of the vertex portion and the wire bonding portion, and determines that there is wire deformation or abnormality in the bonding position when there is a difference greater than or equal to a certain value.

3. The inspection device according to claim 1, further comprising: a laser displacement meter, which is disposed above the conductor and measures the height position of the conductor; and a moving mechanism that moves the semiconductor device in two dimensions, The moving mechanism moves the semiconductor device so that the laser displacement meter is located above the wire bonding portion. The laser displacement meter irradiates the area of ​​the wire bonding portion where the brightness is brighter than the surrounding area with laser light, and measures the height position of the wire bonding portion.

4. The inspection device according to claim 3, wherein: There are two laser displacement meters, With respect to the two laser displacement meters, the laser of one of the laser displacement meters is irradiated onto the area of ​​the wire bonding portion that is brighter than the surrounding area to measure the height position of the wire bonding portion, and at the same time, the laser of the other laser displacement meter is irradiated onto the portion of the semiconductor device located near the wire bonding portion to measure the height position of the portion of the semiconductor device, thereby measuring the difference between the height position of the wire bonding portion and the height position of the portion of the semiconductor device.

5. The inspection device according to claim 1, wherein: The inspected workpiece is a plurality of wires having a diameter greater than or equal to 100 μm, The control device obtains the two-dimensional position information of the area whose brightness is brighter than the surrounding area at the vertices of the plurality of wires from the image, measures the distance between the plurality of vertices of the plurality of wires based on the obtained two-dimensional position information, and compares the measured distance between the vertices with the pre-set distance between the plurality of vertices.

6. The inspection device according to claim 1, wherein: The control device detects the two-dimensional shape of the wire by tracking the region having a brightness darker than surrounding areas from the position of the wire bonding portion toward the position of the vertex portion in the image.

7. An inspection method for detecting abnormality of an inspection workpiece after both ends are wire-bonded to a joining portion of a semiconductor device by a wedge bonding method, in, The workpiece to be inspected is a wire with a diameter greater than or equal to 100 μm, The inspection method has the following steps: In order to obtain the two-dimensional position information of the conductor, an image of the conductor is photographed from above the conductor by a photographing device; irradiating the wire with coaxial illumination light coaxially with the camera; as well as The two-dimensional position information of a region at the top of the wire whose brightness is brighter than the surrounding area and a region at a wire bonding portion which is a joining part of the wire whose brightness is brighter than the surrounding area is acquired from the image.

8. The inspection method according to claim 7, wherein: After the process of obtaining the two-dimensional position information, the obtained two-dimensional position information of the area at the vertex portion whose brightness is brighter than the surrounding area and the area at the wire bonding portion whose brightness is brighter than the surrounding area are compared with the pre-set two-dimensional position information of the vertex portion and the wire bonding portion, and when there is a difference greater than or equal to a certain value, it is determined that there is wire deformation or abnormality in the bonding position.

9. The inspection method according to claim 7, wherein: After the step of obtaining the two-dimensional position information, the following steps are also performed: Measuring the height position of the conductor from above the conductor using a laser displacement meter; and moving the semiconductor device in two dimensions, In the step of moving the semiconductor device in two-dimensional directions, the semiconductor device is moved so that the laser displacement meter is located above the wire bonding portion. In the step of measuring the height position of the wire, a laser beam is irradiated onto the region of the wire bonding portion where the brightness is brighter than surrounding areas, and the height position of the wire bonding portion is measured.

10. The inspection method according to claim 9, wherein: The process of measuring the height position of the conductor is performed by two laser displacement meters. With respect to the two laser displacement meters, the laser light of one of the laser displacement meters is irradiated onto the area of ​​the wire bonding portion whose brightness is brighter than the surrounding area, and the height position of the wire bonding portion is measured. At the same time, the laser light of the other laser displacement meter is irradiated onto the portion of the semiconductor device located near the wire bonding portion, and the height position of the portion of the semiconductor device is measured, thereby measuring the difference between the height position of the wire bonding portion and the height position of the portion of the semiconductor device.

11. The inspection method according to claim 7, wherein: The inspected workpiece is a plurality of wires having a diameter greater than or equal to 100 μm, In the process of obtaining the two-dimensional position information, the two-dimensional position information of the area whose brightness is brighter than the surrounding area and exists at the vertices of the plurality of the wires is obtained from the image, the distances between the plurality of the vertices of the plurality of the wires are measured based on the obtained two-dimensional position information, and the measured distances between the vertices are compared with the pre-set distances between the plurality of vertices.

12. The inspection method according to claim 7, wherein: After the step of acquiring the two-dimensional position information, the method further includes the step of detecting the two-dimensional shape of the wire by tracing the region having a brightness darker than surrounding areas from the position of the wire bonding portion toward the position of the vertex portion in the image.

Images