Semiconductor inspection equipment and semiconductor manufacturing equipment

Abstract

To provide a semiconductor inspection device that is particularly suitable for visual inspection of power semiconductors capable of eliminating products with poor appearance while detecting defects even when there are irregularities such as wires on the surface of an object to be inspected in a series of appearance inspection processing, and a semiconductor manufacturing system.SOLUTION: A disclosed semiconductor inspection device is a semiconductor inspection device for visual inspection of a semiconductor module mounted with multiple semiconductor elements connected by wires on the surface as the inspection object. The semiconductor inspection device includes: a first light source unit that is placed in a first housing and emits a specific wavelength band or white light constituting a coaxial epi-illumination system for the inspection target; and a second light source unit that irradiates the inspection object with light in at least one wavelength range in the red band, blue band, or infrared range diagonally from light sources arranged in a ring shape around the optical axis of the incident light of the coaxial epi-illumination system.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a semiconductor inspection device and a semiconductor manufacturing device, and more particularly to a semiconductor inspection device and a semiconductor manufacturing device suitable for visual inspection of power semiconductors. [Background technology]

[0002] In an optical appearance inspection device for inspecting the appearance of semiconductor wafers and the like, Patent Document 1 discloses a method for inspecting the surface by changing the wavelength of the coaxial epi-illumination light irradiated onto the inspection target using a wavelength filter, which makes it possible to detect defects such as foreign matter or scratches present on the surface.

[0003] Due to the demand for higher performance in power semiconductors, several types of semiconductor elements such as ICs (Integrated Circuits), IGBTs (Insulated Gate Bipolar Transistors), FwDi (Free Wheeling Diodes), and Conv.-Di (Converter Diodes) are electrically connected by wires and modularized. Visual inspection of the surfaces of these semiconductor elements requires coaxial epi-illumination with multiple colors depending on the film quality.

[0004] Regarding the relationship between camera imaging and illumination color, Non-Patent Document 1, for example, shows a schematic diagram of imaging when white, red, green, and blue illumination are used. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-212431 [Non-patent literature]

[0006] [Non-Patent Document 1] "Basic knowledge of LED lighting for image processing: Improving inspection images through lighting selection," Optex FA Co., Ltd., p. 47, https: / / www.optex-fa.jp / online_learning2021 / textbox / d1_text.pdf Summary of the Invention [Problem to be solved by the invention]

[0007] Conventional optical visual inspection systems are capable of detecting defects in flat inspection targets such as semiconductor wafers. However, for inspection targets such as power semiconductor modules that have irregularities on the surface due to wires or other components, simply changing the illumination color of the coaxial epi-illumination system is insufficient to detect defects, making it difficult to completely eliminate products with defective appearances.

[0008] The present disclosure has been made to solve the above-mentioned problems, and its primary object is to provide a semiconductor inspection device that can detect defects and reject visually defective products even when there are irregularities such as wires on the surface of the object being inspected during the visual inspection process.

[0009] Furthermore, a second object of the present disclosure is to provide a semiconductor manufacturing apparatus that can detect defects and reject visually defective products even when there are irregularities such as wires on the surface of the object being inspected during the visual inspection process. [Means for solving the problem]

[0010] A first aspect of the present disclosure is a semiconductor inspection device that performs a visual inspection of a semiconductor module, which is an object to be inspected, and which has a plurality of semiconductor elements connected by wires mounted on a surface thereof, the semiconductor module comprising: a first light source unit disposed in the first housing and emitting light in a specific wavelength band or white light; a half mirror that is disposed in a second housing coupled to the first housing, and that reflects a portion of the light that is emitted from the first light source unit and passes through the first housing, and generates incident light that is perpendicularly incident on the inspection object; a camera that is arranged coaxially with an optical axis of the incident light and an optical axis of reflected light generated by reflection of the incident light from the inspection object, and captures an image of transmitted light that has passed through the half mirror; a second light source unit that obliquely irradiates the inspection object with light of at least one wavelength range of a red band, a blue band, or an infrared band from light sources arranged in a ring shape around the optical axis of the incident light; Equipped with 、 The first light source unit is an optical disc in which a plurality of LED lights with different wavelength ranges are arranged radially, and switching between the wavelength ranges does not involve rotation. It is preferable.

[0011] A second aspect of the present disclosure provides a semiconductor module manufacturing method, comprising: a first unit that performs a manufacturing process of bonding a back surface of a semiconductor element to a semiconductor module body; a second unit for performing a manufacturing process of electrically connecting electrodes exposed from another device to the surface of the semiconductor element; It is preferable that the semiconductor inspection apparatus further comprises a third unit that is equipped with the semiconductor inspection apparatus according to claim 1 and that performs a visual inspection of the semiconductor modules manufactured in the first unit and the second unit. [Effects of the Invention]

[0012] According to the first and second aspects of the present disclosure, it is possible to provide a semiconductor inspection device and a semiconductor manufacturing device that can detect defects and reject visually defective products even when there are irregularities such as wires on the surface of the object being inspected during the visual inspection process. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a diagram illustrating an example of the configuration of a semiconductor inspection device according to a first embodiment of the present disclosure. [Figure 2] 1 is a diagram illustrating a configuration example of a bandpass filter disk according to a first embodiment of the present disclosure. [Figure 3] 1 is a diagram illustrating a configuration example of a ring illumination according to a first embodiment of the present disclosure. [Figure 4] 3 illustrates an example of a functional configuration of an image processing unit according to the first embodiment of the present disclosure. [Figure 5] 1A and 1B show configuration examples of a case where the functions of an image processing unit according to the first embodiment of the present disclosure are realized by (a) hardware and (b) software. [Figure 6] FIG. 3 is a diagram illustrating a first role of a filter according to the first embodiment of the present disclosure. [Figure 7] FIG. 4 is a diagram illustrating a second role of a filter according to the first embodiment of the present disclosure. [Figure 8] FIG. 10 is a diagram illustrating a configuration example of a semiconductor inspection device according to a second embodiment of the present disclosure. [Figure 9] FIG. 10 is a diagram illustrating an example configuration of an optical board according to a second embodiment of the present disclosure. [Figure 10] FIG. 10 is a diagram illustrating a configuration example of a semiconductor inspection device according to a third embodiment of the present disclosure. [Figure 11] FIG. 10 is a diagram illustrating a configuration example of a semiconductor inspection device according to a fourth embodiment of the present disclosure. [Figure 12] FIG. 10 is a diagram illustrating an example of the configuration of a second optical disc according to a fourth embodiment of the present disclosure. [Figure 13] FIG. 10 is a diagram illustrating a configuration example of a semiconductor manufacturing apparatus according to a fifth embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0014] Embodiment 1 FIG. 1 is a diagram illustrating an example configuration of a semiconductor inspection device according to a first embodiment of the present disclosure. In the semiconductor inspection device 100, a first cylinder 101 includes a light source 102 having continuous wavelengths in the visible light range. The light source 102 is, for example, a halogen lamp. The light emitted from the light source 102 (hereinafter referred to as broad light 103) passes through the first cylinder 101 and passes through one of a plurality of bandpass filters (hereinafter referred to as filters) arranged on a bandpass filter disk 120. The light that passes through the filter is wavelength-selected and converted into monochromatic light 104 having a wavelength spectrum centered around a specific wavelength in the visible light range.

[0015] After passing through the first cylinder 101, the monochromatic light 104 is incident on a half mirror 106 inside a second cylinder 105 that is connected to the first cylinder 101. The half mirror 106 is positioned so that the monochromatic light 104 is incident at an angle, and reflects a portion of the incident monochromatic light 104 vertically downward. The monochromatic light 104 reflected vertically downward becomes normal incident light 108 that is incident normal to an inspection object 107.

[0016] The normal incident light 108 is specularly reflected by an inspection object 107 placed on a stage 109, and becomes return light 110 that returns into the second cylinder 105. When the return light 110 enters the half mirror 106, a portion of it is transmitted, and the transmitted light is focused on a camera 111. The camera 111 is disposed coaxially with the optical axes of the normal incident light 108 and the return light. The camera 111 is an image sensor having an imaging element such as a CCD (Charge Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor) that has a detection wavelength range in the visible light region.

[0017] In this way, the light emitted from the light source 102 provided in the first cylinder 101 constitutes a coaxial epi-illumination system 112 in which the optical axes of the perpendicular incident light 108 incident on the inspection object 107 and the returned light 110 reflected from the inspection object 107 coincide with the optical axis of the camera 111. The coaxial epi-illumination system 112 is an optical system including the light source 102, the broad light 103, the monochromatic light 104, the half mirror 106, the perpendicular incident light 108, the returned light 110, and the bandpass filter disk 120.

[0018] Meanwhile, ring illumination 130 provided at the vertically lower end of second cylinder 105 irradiates inspection object 107 with oblique light 113 that is incident at an angle. The angle of incidence of oblique light 113 is different from that of perpendicularly incident light 108. Oblique light 113 is reflected by inspection object 107, but most of it is specularly reflected and does not reach camera 111 in the vertically upward direction. However, among the diffusely reflected light that occurs simultaneously with specular reflection, there is reflected light (hereinafter referred to as diffused return light 114) that travels vertically upward and reaches camera 111.

[0019] In this way, the light emitted from ring illumination 130 constitutes ring illumination system 115. Ring illumination system 115 is an optical system including ring illumination 130, oblique light 113, and diffused returning light 114.

[0020] The return light 110 and the diffuse return light 114 that reach the camera 111 are captured by an imaging element and output as an image signal to the image processing unit 140. Based on the input image signal, the image processing unit 140 detects defects such as foreign matter or scratches present on the surface and performs an appearance inspection to determine the appearance quality.

[0021] As described above with reference to FIG. 1, the semiconductor inspection device 100 is equipped with two types of illumination systems and performs a visual inspection of an object to be inspected.

[0022] It should be noted that the image processing unit 140 does not necessarily have to be included as a component in the semiconductor inspection apparatus 100. In this embodiment and the following embodiments, unless otherwise specified, the semiconductor inspection apparatus does not include an image processing unit.

[0023] Continuing with reference to FIG. 1, the following describes inspection targets suitable for the coaxial epi-illumination system 112 and the ring illumination system 115.

[0024] The coaxial epi-illumination system 112 is suitable for an inspection object 107 with a flat surface. In the coaxial epi-illumination system 112, a sufficient amount of specularly reflected light from the flat portion reaches the camera 111, which can create a large difference in reflectance with respect to portions that are not specularly reflected due to defects, etc. This allows the flat portion and other portions to be distinguished and observed with high contrast.

[0025] On the other hand, the coaxial epi-illumination system 112 causes diffused reflection for the inspection object 107 having an uneven surface, and is unable to produce a difference in surface reflectance. Because it is difficult to focus the diffused light onto the camera 111, the image obtained is low in contrast, making it difficult to detect minute defects or foreign matter in the uneven surface.

[0026] In contrast, the ring illumination system 115 is suitable for an inspection object 107 that has an uneven surface. When oblique light 113 emitted from the ring illumination system 130 is incident on the uneven portion of the surface, it is diffusely reflected, and the diffused returning light 114 reaches the camera, allowing the appearance of the uneven portion to be observed. This makes it possible to detect defects such as unevenness or foreign matter that cannot be detected with the coaxial epi-illumination system 112.

[0027] In the semiconductor inspection device 100 of this embodiment, the light source 102 provided in the first cylinder 101 and the ring illumination system 130 provided in the second cylinder 105 are unitized. This allows the coaxial epi-illumination system 112 and the ring illumination system 115 to be switched and used within one unit.

[0028] By using the coaxial epi-illumination system 112, it is possible to obtain a clear image with a high contrast of specular reflection. On the other hand, by using the ring illumination system 115, it is possible to obtain an image of the surface irregularities. By combining these two types of illumination systems, it is possible to inspect the inspection target 107 in more detail during visual inspection and detect defects such as foreign particles or scratches on the surface.

[0029] FIG. 2 is a diagram illustrating an example configuration of a bandpass filter disk according to the first embodiment of the present disclosure. Bandpass filter disk 120 includes multiple filters that selectively transmit only light of specific wavelength bands in the visible light range. For example, in the example of FIG. 2, bandpass filter disk 120 includes red filter 121, green filter 122, and blue filter 123, which transmit wavelengths in the red, green, and blue bands, respectively. Bandpass filter disk 120 also includes colorless filter 124, which has no wavelength selectivity. Hereinafter, when there is no need to specify a specific color filter and the same designation is used for all color filters, a new reference symbol will be used, referring to filter 125.

[0030] The filters 125 of each color are arranged in a ring shape on the bandpass filter disk 120. Furthermore, the bandpass filter disk 120 has a rotation axis parallel to the central axis of the first cylinder 101 and rotates around the rotation axis. As the bandpass filter disk 120 rotates, each filter 125 passes in turn through the optical path of the broad light 103 emitted from the light source 102. By fixing the filter 125 that transmits only the desired wavelength band on the optical path, the light from the light source 102 can be converted into the desired monochromatic light 104.

[0031] 2, the bandpass filter disk 120 is described as having all of the red, green, blue, and white filters. However, it is not necessary to have all of these colors at the same time. Furthermore, the wavelengths selected by the filters are not limited to the red, green, blue, and white bands, and may be other colors. An appropriate selection may be made depending on the characteristics of the object to be inspected by the semiconductor inspection equipment 100, the sensitivity performance of the camera 111, etc.

[0032] 3 is a diagram illustrating an example of the configuration of a ring illumination according to the first embodiment of the present disclosure. The ring illumination 130 includes a plurality of illumination light sources 131 evenly arranged in a ring shape. The illumination light sources 131 use LEDs (Light Emitting Diodes) with high ON / OFF response to reduce the waiting time for switching between the coaxial epi-illumination system 112 and the ring illumination system 115.

[0033] The wavelength range of the illumination light source 131 is basically the red band (high wavelength band) which shows high reflectivity in the visible light range so as to obtain good reflection characteristics for gold, silver, and copper, which are the main materials for wires in semiconductor modules. However, a low wavelength blue band or the infrared range may be used in order to intentionally image gold as dark. Furthermore, the intensity of the illumination light source 131 can be adjusted to obtain a clear contrast image.

[0034] The arrangement of the plurality of illumination light sources 131 is not limited to the example shown in FIG. 3, but may be arranged in accordance with the size of the housing of the ring illumination 130 and the illumination light sources 131.

[0035] 4 shows an example of the functional configuration of an image processing unit according to the first embodiment of the present disclosure. Input unit 141 is an interface to which an image signal from camera 111 is input. Image processing unit 142 is an inspection pre-processing unit that performs image editing such as binarization processing on the image signal. Appearance inspection unit 143 is a unit that judges the appearance quality of inspection object 107 based on image-processed data. Result output unit 144 is a unit that outputs the judgment result.

[0036] 5 shows configuration examples in which the functions of the image processing unit according to the first embodiment of the present disclosure are realized (a) by hardware and (b) by software. The input unit 141 described in FIG. 4 is a receiving device 145, and the result output unit 144 is a display 147. Furthermore, the functions of the image processing unit 142 and the appearance inspection unit 143 are realized by a processing circuit. The processing circuit may be implemented using dedicated hardware as shown in FIG. 5(a). Alternatively, the processing circuit may be implemented by software using a CPU (Central Processing Unit, also referred to as a processor) that executes a program stored in memory as shown in FIG. 5(b).

[0037] When the processing circuit is dedicated hardware, the processing circuit 146 may be, for example, a single circuit, a decoding circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or a combination thereof. The functions of the image processing unit 142 and the appearance inspection unit 143 may be performed by the processing circuit 146 individually, or the functions of each unit may be performed by the processing circuit 146 collectively.

[0038] When the processing circuit is a CPU, the functions of the image processing unit 142 and the appearance inspection unit 143 are realized by software, firmware, or a combination of these. The software or firmware is written as a program and stored in memory 149. The processing circuit realizes the functions of each unit by reading and executing the program recorded in memory 149. It can also be said that these programs cause a computer to execute the procedures or methods of the image processing unit 142 and the appearance inspection unit 143. Here, memory 149 corresponds to, for example, a volatile or non-volatile semiconductor memory such as RAM, ROM, or flash memory, or a magnetic disk, flexible disk, optical disk, DVD, etc.

[0039] 6 is a diagram illustrating a first role of a filter according to the first embodiment of the present disclosure. Non-Patent Document 1 provides a schematic diagram showing the relationship between the contrast of an image captured by a camera and the color of the illumination. In FIG. 6, the upper diagram shows an image captured by a color camera, and the lower diagram shows an image captured by a monochrome camera.

[0040] First, in the image captured by the color camera under white light (panel P10 in FIG. 6), differences in color can be distinguished as with the naked eye. For example, red area 160(1), green area 160(2), and blue area 160(3) can be distinguished.

[0041] On the other hand, in the image captured by a monochrome camera under white light (panel P11), the differences between each color area 160 are expressed by the contrast between black and white. As such, in the visual inspection process of semiconductor manufacturing, it is not uncommon for images to be captured using a monochrome camera, or for images captured by a color camera to be converted to black and white through image processing for visual quality inspection. In such cases, if the image has low black and white contrast, it becomes difficult to detect defects through binarization processing.

[0042] This problem can be addressed by selecting the appropriate illumination color. For example, in the monochrome camera image acquired under blue illumination (panel P12), the difference between the red area 160(1) and the blue area 160(3) is more pronounced than in the image acquired under white illumination (panel P11).

[0043] In the semiconductor inspection device 100, by using a filter 125 of an appropriate color, the wavelength of the light source 102 can be changed and a clearer contrast image can be obtained in the camera 111. This can improve the accuracy of defect detection in the appearance inspection process.

[0044] 7 is a diagram illustrating a second role of a filter according to the first embodiment of the present disclosure. First, assume that, when observed visually, a color gradation due to uneven film thickness exists on the surface of the inspection object 107 (panel P20). Here, assume that blue increases toward the upper left end of the inspection object 107 and green increases toward the lower right end. An image (panel P21) of this inspection object 107 captured by a color camera using illumination transmitted through a colorless filter 124 is similar to the image observed visually (panel P20).

[0045] On the other hand, even under the same white illumination, the image captured by the monochrome camera (panel P22) shows no contrast across the surface of the inspection object 107, resulting in an image with uniform brightness. This is due to the fact that, based on the principle explained in FIG. 6, there is no significant difference in contrast between the green area 160(2) and the blue area 160(3) under white illumination (panel P11 in FIG. 6). This effect is advantageous in the appearance inspection process of semiconductor manufacturing, as it prevents brightness shading caused by film thickness unevenness and makes it easier to distinguish between flat and other surface areas through binarization processing. In this way, by using white illumination and capturing a monochrome image, it is possible to capture an image with uniform brightness across the surface, even if the inspection object 107 has film thickness unevenness.

[0046] On the other hand, an image (panel P23) of the same inspection object 107 as panel P20 captured with a monochrome camera under blue illumination transmitted through a blue filter 123 exhibits a stronger gradation than that captured under white illumination (panel P22). This is due to the large difference in contrast between the green area 160(2) and the blue area 160(3) under blue illumination, as explained in FIG. 6 (panel P12 in FIG. 6). In the appearance inspection process, this effect causes brightness shading due to film thickness unevenness, which creates contrast differences even on a flat surface, and is therefore detrimental to binarization processing.

[0047] As described above, by using an appropriate filter 125, it is possible to change the wavelength of the light source 102, prevent brightness shading caused by uneven film thickness in the camera 111, and obtain an image with uniform brightness. This improves the accuracy of defect detection in the semiconductor inspection equipment 100.

[0048] As described above with reference to FIGS. 1 to 7 , the semiconductor inspection apparatus 100 of this embodiment performs visual inspection by switching between the coaxial epi-illumination system 112 and the ring illumination system 115. Furthermore, in the coaxial epi-illumination system 112, wavelength selection is performed using the bandpass filter disk 120. Additionally, in the ring illumination system 115, a wavelength is selected so as to obtain the desired reflection characteristics for the material constituting the object to be inspected. In this way, by using two types of illumination systems and appropriately selecting the wavelengths of each illumination system, it is possible to obtain an image in which flat and uneven portions, differences in material, etc. of the inspection object 107 can be distinguished with high contrast. In this way, the semiconductor inspection apparatus 100 can detect defects and reject visually defective products even when the surface of the inspection object is uneven during the visual inspection process.

[0049] The semiconductor inspection device 100 described in this embodiment is particularly effective in visual inspection of a semiconductor module having a surface on which a plurality of semiconductor elements electrically connected by wires are mounted as the inspection object 107. For example, in a power semiconductor module used for power control, the inspection object is suitable for inspecting flat chips and uneven wires, as well as defects formed on these, such as scratches, foreign matter, abnormal wire bonding shapes, and abnormal wire loop shapes.

[0050] By using two types of illumination systems provided in the semiconductor inspection apparatus 100 of the present disclosure and appropriately selecting the wavelength of each illumination system, it is possible to obtain effects beyond simply capturing images of the edge of the lead frame in a power semiconductor module. For example, it is possible to obtain clear images of the edges of semiconductor chips mounted on the lead frame. Furthermore, it is possible to obtain images of defect edges or wire edges on the order of several microns formed on the chip.

[0051] [Variations] In the example of Fig. 1, a halogen lamp is used as the light source 102. However, a white LED may also be used. Use of a white LED enables high-intensity light emission, making it possible to acquire higher-contrast images in the coaxial epi-illumination system 112. Furthermore, since an LED has a faster on / off response than a halogen lamp, it is possible to reduce the waiting time when switching to the ring illumination system 115, thereby shortening the inspection takt time.

[0052] The semiconductor elements included in the semiconductor module inspected by the semiconductor inspection apparatus 100 of this embodiment are not limited to those made of silicon, but may also be made of wide-bandgap semiconductors with a wider bandgap than silicon. Examples of wide-bandgap semiconductors include silicon carbide, gallium nitride-based materials, and diamond. Semiconductor elements made of such wide-bandgap semiconductors have high voltage resistance and allowable current density, allowing for miniaturization. By using these miniaturized semiconductor elements, semiconductor modules incorporating these semiconductor elements can also be miniaturized and highly integrated. Furthermore, the high heat resistance of the semiconductor elements allows for miniaturization of the heat sink's heat dissipation fins, enabling air-cooling instead of water-cooling, further miniaturizing the semiconductor module. Furthermore, the low power loss and high efficiency of the semiconductor elements allow for high efficiency semiconductor modules. While it is desirable for all semiconductor elements to be made of wide-bandgap semiconductors, any one of the semiconductor elements may be made of a wide-bandgap semiconductor, and the effects described in this embodiment can still be achieved. This point is common to all of the following embodiments.

[0053] In this embodiment, a case has been described in which the housing in which the light source 102 and the bandpass filter disk 120 are disposed is a cylindrical first cylinder 101, and the housing in which the ring illumination 130 is disposed is a cylindrical second cylinder 105. However, the shape of the housing does not have to be limited to a cylindrical shape, and it may be designed appropriately according to the conditions of use of the semiconductor inspection apparatus 100. This point is common to all of the following embodiments.

[0054] Furthermore, the semiconductor inspection device 100 in this embodiment is not limited to the example shown in Fig. 1, and various modifications can be made in the implementation stage without departing from the spirit of the invention. For example, the semiconductor inspection device 100 may include multiple optical elements such as lenses for adjusting the optical axis and focus. This point is also common to the following embodiments.

[0055] Embodiment 2 8 is a diagram showing an example of the configuration of a semiconductor inspection apparatus according to the second embodiment of the present disclosure. The semiconductor inspection apparatus 200 has a structure in which the light source 102 and the bandpass filter disk 120 of the coaxial epi-illumination system 112 in the semiconductor inspection apparatus 100 according to the first embodiment are replaced with an optical disk 220.

[0056] The optical disk 220 is provided on the first cylinder 101 and functions as a light source for the coaxial epi-illumination system 112. The optical disk 220 has a plurality of light sources having different wavelengths in the visible light range, and by selecting one of them, it is possible to generate the monochromatic light 104 for the coaxial epi-illumination system 112. Unlike the wavelength selection using the filter 125 described in the first embodiment, there is no attenuation of the light amount, so that high-intensity light can be irradiated onto the inspection object 107, and an image with higher contrast can be acquired compared to the first embodiment.

[0057] 9 is a diagram illustrating an example configuration of an optical board according to the second embodiment of the present disclosure. The optical board 220 includes multiple colors of LED lighting, each consisting of multiple LED light sources of the same color. For example, in the example of FIG. 4, the optical board includes a red LED lighting 221 consisting of multiple red LED light sources. Similarly, the optical board includes a green LED lighting 222, a blue LED lighting 223, and a white LED lighting 224. Note that, hereinafter, when there is no need to specify a specific color of LED lighting and the same designation is used for all colors of LED lighting, a new reference symbol will be used, describing the LED lighting 225.

[0058] The LED lights 225 of each color are arranged in a ring shape on the optical plate 220. Furthermore, similar to the bandpass filter plate 120 of the first embodiment, the optical plate 220 has a rotation axis parallel to the central axis of the first cylinder 101. Also, similar to the first embodiment, the rotation of the optical plate 220 causes each of the LED lights 225 to face the reflective surface of the half mirror in turn.

[0059] In this way, by using the LED illumination 225 composed of multiple LEDs of the same color, it is possible to generate monochromatic light 104 with a sufficient light intensity and illumination area in the coaxial epi-illumination system 112. This makes it possible to obtain a high-contrast image while ensuring a sufficient observation field of view.

[0060] As described above, in the semiconductor inspection device 200 of this embodiment, the coaxial epi-illumination system 112 uses the optical disc 220 equipped with multiple colors of LED illumination 225, which is made up of multiple LED light sources of the same color, as a light source. This prevents light from attenuating when selecting wavelengths, making it possible to acquire images with higher contrast.

[0061] It should be noted that the coaxial epi-illumination system 112 in this embodiment is an optical system including the monochromatic light 104 , the half mirror 106 , the perpendicular incident light 108 , the return light 110 , and the optical disk 220 .

[0062] Embodiment 3 10 is a diagram showing an example of the configuration of a semiconductor inspection device according to the third embodiment of the present disclosure. The semiconductor inspection device 300 has a structure in which a stepping motor 320 is connected to the optical board 220 by a shaft 310 in the semiconductor inspection device 200 according to the second embodiment. The shaft 310 of the stepping motor 320 is fixed to the center of rotation of the optical board 220, and the optical board 220 can be rotated automatically by motor control.

[0063] In the semiconductor inspection device 300, the timing of capturing the image of the inspection object 107 by the camera 111 and the timing of rotating the optical disc 220 by the stepping motor 320 are synchronized, so that the LED lights 225 of each color can be automatically illuminated in sequence and the image can be captured. This eliminates the need to manually switch the LED lights 225 for inspection objects 107 with various structures and colors, making it possible to automate the inspection process.

[0064] Embodiment 4 11 is a diagram showing an example of the configuration of a semiconductor inspection device according to the fourth embodiment of the present disclosure. The semiconductor inspection device 400 has a second optical board 420 that is different in size and arrangement of LED lights 225 from the optical board 220 of the semiconductor inspection device 200 according to the second embodiment.

[0065] The second optical plate 420 is provided on the first cylinder 101, but unlike the above-mentioned optical plate 220, it does not rotate. The size of the second optical plate 420 is approximately the same as the cross-sectional size of the first cylinder 101. In the second optical plate 420, the LED lights 225 of each color are arranged so that the light emitted from each passes through the first cylinder.

[0066] Moreover, semiconductor inspection apparatus 400 further includes an LED control unit 430 connected to camera 111 and second optical board 420. LED control unit 430 selects and turns on one of LED lights 225 in synchronization with the timing of image capture by camera 111. This not only makes it possible to irradiate monochromatic light 104 with a wavelength selected in synchronization with the timing of image capture by camera 111, as in the third embodiment, but also obviates the need for large optical board 220 with a rotation axis and stepping motor 320. This allows the size of the units of coaxial epi-illumination system 112 and ring illumination system 115 attached to the head of camera 111 to be reduced.

[0067] It should be noted that the LED control unit 430 does not necessarily have to be included as a component of the semiconductor inspection device 400.

[0068] It should be noted that the coaxial epi-illumination system 112 in this embodiment is an optical system including monochromatic light 104 , half mirror 106 , perpendicularly incident light 108 , returning light 110 , and second optical plate 420 .

[0069] 12 is a diagram illustrating an example configuration of a second optical board according to the fourth embodiment of the present disclosure. Second optical board 420 has a structure in which LED lights 225, each composed of a plurality of LEDs of the same color, are arranged radially. For example, in the example of FIG. 7, red LED light 221, composed of a plurality of red LEDs, is provided. Next to it, green LED light 222, blue LED light 223, and white LED light 224 are provided in this order, and these are arranged repeatedly.

[0070] In this way, by repeatedly arranging the LED lights 225 of each color radially, it is possible to equalize the intensity of the monochromatic light 104 of each color emitted from the second optical board 420. Furthermore, in the coaxial epi-illumination system 112, it is possible to generate perpendicularly incident light 108 with a uniform in-plane intensity distribution.

[0071] 11 and 12, the semiconductor inspection equipment 400 of this embodiment uses a second optical board 420 in which LED lights 225 of each color are repeatedly arranged radially. Furthermore, the selection of the illumination color of the coaxial epi-illumination system 112 and the timing of image capture by the camera 111 are controlled by an LED control unit 430. This makes it possible to simultaneously achieve miniaturization and automation of the equipment.

[0072] In this embodiment, the LED lights 225 of each color are repeatedly arranged radially on the second optical board 420. However, the arrangement of the LED lights 225 of each color is not limited to this, and they may be arranged in a suitable manner according to the conditions of use of the semiconductor inspection device 400.

[0073] The functions of the LED control unit 430 in this embodiment may be realized by software using a computer equipped with a CPU and memory and storing a program in the memory, or may be realized by hardware using a dedicated circuit such as an FPGA or ASIC.

[0074] Fifth embodiment 13 is a diagram showing an example of the configuration of a semiconductor manufacturing apparatus according to a fifth embodiment of the present disclosure. Semiconductor manufacturing apparatus 500 includes a die bond station 501, a wire bond station 502, and an appearance inspection station 503. Die bond station 501 is a portion within semiconductor manufacturing apparatus 500 that performs a manufacturing process of bonding the back surface of a semiconductor element to a mother body of a power semiconductor module. Similarly, wire bond station 502 is a portion that performs a manufacturing process of electrically connecting electrodes exposed from an external device to the front surface of a semiconductor element mounted on a power semiconductor module. Furthermore, appearance inspection station 503 includes any of the semiconductor inspection devices described in the first to fourth embodiments and performs an appearance inspection process.

[0075] In this way, by fabricating semiconductor manufacturing equipment 500 that performs the manufacturing process and the inspection process all at once, it is possible to reduce the installation area and realize a miniaturized footprint.

[0076] As described above, according to the first to fifth embodiments of the present disclosure, it is possible to provide a semiconductor inspection device and a semiconductor manufacturing device that can detect defects and reject visually defective products even when there are irregularities such as wires on the surface of the object being inspected during the visual inspection process.

[0077] [Explanation of terms used in claims] The components of the coaxial epi-illumination system 112 that generate the monochromatic light 104 described in the first to fourth embodiments are referred to as a first light source unit. For example, in the first embodiment, the first light source unit refers to the light source 102 and the bandpass filter disk 120. Similarly, in the second embodiment, the first light source unit refers to the optical disk 220. In the third embodiment, the first light source unit refers to the optical disk 220, the shaft 310, and the stepping motor 320. In the fourth embodiment, the first light source unit refers to the second optical disk 420.

[0078] Similarly, the light source of ring illumination system 115 described in the first to fourth embodiments is called a second light source unit. The second light source unit is ring illumination .

[0079] First cylinder 101 and second cylinder 105 described in the first to fourth embodiments are referred to as a first housing and a second housing, respectively.

[0080] The die bonding station 501 described in the fifth embodiment is called the first unit. Similarly, the wire bonding station 502 is called the second unit, and the appearance inspection station 503 is called the third unit. [Explanation of symbols]

[0081] 100, 200, 300, 400 Semiconductor inspection equipment 101 First Cylinder 102 Light source 103 Broad Light 104 Monochromatic Light 105 Second Cylinder 106 Half Mirror 107 Inspection object 108 Normally incident light 109 Stages 110 Return light 111 Camera 112 Coaxial epi-illumination system 113 Oblique Light 114 Diffused return light 115 Ring lighting system 120 Bandpass filter board 121 Red Filter 122 Green Filter 123 Blue Filter 124 Colorless Filter 125 filters 130 Ring Light 131 Lighting source 140 Image Processing Unit 141 Input section 142 Image processing section 143 Visual Inspection Department 144 Result output section 145 Receiving device 146 Processing Circuit 147 Display 148 processors 149 memory 160 Red Area, Green Area, Blue Area 220 Optical disc 221 Red LED lighting 222 Green LED lighting 223 Blue LED lighting 224 White LED lighting 225 LED lighting 310 shaft 320 stepper motor 420 Second optical disc 430 LED control unit 500 Semiconductor manufacturing equipment 501 Die Bond Station 502 Wire Bond Station 503 Visual Inspection Station

Claims

1. A semiconductor inspection device that performs a visual inspection of a semiconductor module, which is an object to be inspected and which has a plurality of semiconductor elements connected by wires mounted on its surface, comprising: a first light source unit disposed in the first housing and emitting light in a specific wavelength band or white light; a half mirror that is disposed in a second housing coupled to the first housing, and that reflects a portion of the light that is emitted from the first light source unit and passes through the first housing, and generates incident light that is perpendicularly incident on the inspection object; a camera that is arranged coaxially with an optical axis of the incident light and an optical axis of reflected light generated by reflection of the incident light from the inspection object, and captures an image of transmitted light that has passed through the half mirror; a second light source unit that obliquely irradiates the inspection object with light of at least one wavelength range of a red band, a blue band, or an infrared band from light sources arranged in a ring shape around the optical axis of the incident light; Equipped with The first light source unit is an optical disc in which a plurality of LED lights having different wavelength ranges are radially arranged, and the switching of the wavelength ranges does not involve rotation. Semiconductor inspection equipment.

2. 2. The semiconductor inspection device according to claim 1, wherein the wires connecting the semiconductor elements are made primarily of at least one of gold, silver, and copper.

3. 2. The semiconductor inspection device according to claim 1, wherein the plurality of LED lights having different wavelength ranges are repeatedly arranged radially on the optical board.

4. further comprising an LED control unit connected to the optical board and the camera; 4. The semiconductor inspection device according to claim 1, wherein the LED control unit selects and lights up at least one of the plurality of LED lights in synchronization with the timing of imaging by the camera.

5. 2. The semiconductor inspection device according to claim 1, wherein the first housing and the second housing are cylindrical.

6. further comprising an image processing unit; The image processing unit A process in which an image signal is input; image processing for editing an image on the image signal; A process of performing an appearance inspection of the inspection object based on the image-processed data; a process of outputting a determination result of the appearance inspection; The semiconductor inspection device of claim 1 , configured to perform the following:

7. 2. The semiconductor inspection device according to claim 1, wherein said semiconductor element is formed of a wide band gap semiconductor.

8. a first unit for performing a manufacturing process of bonding a back surface of a semiconductor element to a mother body of a power semiconductor module; a second unit for performing a manufacturing process of electrically connecting electrodes exposed from another device to the surface of the semiconductor element; A semiconductor manufacturing apparatus comprising: the semiconductor inspection apparatus according to claim 1; and a third unit for performing a visual inspection of power semiconductor modules manufactured in the first unit and the second unit.

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