Method for manufacturing electronic components and method for detecting foreign objects

Abstract

To provide a foreign matter detection method with which it is possible to detect foreign matter on the wiring of electronic components.SOLUTION: The foreign matter detection method comprises steps for: preparing an electronic component that includes a wiring board having a wiring; and detecting foreign matter on the surface of the wiring. The step for detecting the foreign matter includes: (1) irradiating the surface of the wiring with first light having an emission peak wavelength in the range of wavelengths of 350 nm to 495 nm inclusive, in the emission spectrum of which the emission intensity of light in wavelength of 500 nm or greater is 5% or less with respect to emission intensity in the emission peak wavelength, and imaging the surface of the wiring to acquire first image information; (2) irradiating the surface of the wiring with second light that includes light in wavelength of 500 nm or greater and imaging the surface of the wiring to acquire second image information; (3) performing difference processing on the first and second image information to acquire third image information; (4) determining a portion of the third image information that indicates lower brightness than the preset reference value of brightness as the foreign matter, thereby detecting the foreign matter.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a method for manufacturing an electronic component and a method for detecting foreign matter.

Background Art

[0002] As an example of an electronic component, for example, Patent Document 1 discloses a small light source device used in a mobile phone.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] An electronic component has wiring for connecting to other elements such as a mounting substrate. If foreign matter exists in such wiring, for example, there may be a problem of poor connection with the mounting substrate or the like.

[0005] An embodiment according to the present disclosure aims to provide a method for manufacturing an electronic component and a method for detecting foreign matter that can detect foreign matter on the wiring of the electronic component.

Means for Solving the Problems

[0006] The method for manufacturing an electronic component according to the present disclosure includes: a step of preparing an electronic component including a wiring board having wiring; a step of detecting foreign matter on the surface of the wiring, and includes: the step of detecting the foreign matter is: (1) Irradiate the surface of the wiring with first light having an emission peak wavelength in the range of 350 nm to 495 nm, and the emission intensity of light with a wavelength of 500 nm or more in the emission spectrum being 5% or less of the emission intensity at the emission peak wavelength, and acquire first image information by imaging the surface of the wiring. (2) Irradiate the surface of the wiring with a second light containing light with a wavelength of 500 nm or more, and acquire second image information by imaging the surface of the wiring. (3) Perform a difference processing on the first image information and the second image information to obtain the third image information. (4) In the third image information, the portion showing a brightness lower than a preset brightness reference value is determined to be the foreign object, and the foreign object is detected. Includes.

[0007] The method for detecting foreign matter relating to this disclosure is: A detection method for detecting foreign matter on the surface of wiring on a wiring board, (1) Irradiate the surface of the wiring with first light having an emission peak wavelength in the range of 350 nm to 495 nm, and the emission intensity of light with a wavelength of 500 nm or more in the emission spectrum being 5% or less of the emission intensity at the emission peak wavelength, and acquire first image information by imaging the surface of the wiring. (2) Irradiate the surface of the wiring with a second light containing light with a wavelength of 500 nm or more, and acquire second image information by imaging the surface of the wiring. (3) Perform a difference processing on the first image information and the second image information to obtain the third image information. (4) In the third image information, the portion showing a brightness lower than a preset brightness reference value is determined to be the foreign object, and the foreign object is detected. Includes. [Effects of the Invention]

[0008] According to embodiments of this disclosure, it is possible to provide a method for manufacturing an electronic component and a method for detecting foreign matter on the wiring of an electronic component. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic perspective view of an electronic component manufactured by the manufacturing method disclosed herein. [Figure 2] Figure 1 is a schematic plan view of an electronic component. [Figure 3] Figure 1 is a schematic bottom view of the electronic component. [Figure 4] Figure 2 is a schematic cross-sectional view of an electronic component along the IV-IV line. [Figure 5] Figure 1 is a schematic cross-sectional view of a light-emitting device in an electronic component. [Figure 6] This is a schematic cross-sectional view illustrating the method for acquiring the first and second image information. [Modes for carrying out the invention]

[0010] The embodiments for carrying out the invention of this disclosure will be described below with reference to the drawings. The manufacturing method of electronic components and the method for detecting foreign matter described below are intended to embody the technical concept of the invention of this disclosure, and unless otherwise specified, the invention of this disclosure is not limited to the following. In each drawing, components having the same function may be denoted by the same reference numeral. For convenience, the embodiments may be shown separately for the purpose of explaining the key points or for ease of understanding, but it is possible to partially substitute or combine the configurations shown in different embodiments. In the embodiments described later, descriptions of matters common to the preceding will be omitted, and only the differences will be explained. In particular, similar effects and advantages due to similar configurations will not be mentioned sequentially for each embodiment. The size and positional relationships of the components shown in each drawing may be exaggerated to clarify the explanation. In addition, end view diagrams showing only the cut surface may be used as cross-sectional views.

[0011] (Electronic components) The electronic component manufactured by the manufacturing method of the present disclosure will be described while referring to FIGS. 1 to 4. FIG. 1 is a schematic perspective view of an electronic component 101 manufactured by the manufacturing method of the present disclosure. FIG. 2 is a schematic plan view of the electronic component 101. FIG. 3 is a schematic bottom view of the electronic component 101. FIG. 4 is a schematic cross-sectional view of the electronic component 101.

[0012] The electronic component 101 is, for example, an IC, a thermistor, a transistor, a capacitor, a light-emitting element, or a light-receiving element. Further, the electronic component 101 may be, for example, a light-emitting device including a light-emitting element and a substrate on which the light-emitting element is arranged, or a light source device including a light-emitting device and a mounting substrate on which the light-emitting device is arranged. In the present embodiment, as an example, the case where the electronic component is a light source device including a light-emitting device will be described. FIG. 5 is a schematic cross-sectional view of the light-emitting device 5 included in the electronic component 101 (light source device).

[0013] The electronic component 101 manufactured by the manufacturing method of the present disclosure includes a wiring board 3. The wiring board 3 includes a board base material 2 and wirings 1 arranged on its surface. In the present embodiment, the electronic component 101 further includes a light-emitting device 5. The light-emitting device 5 is arranged on the upper surface of the wiring board 3. The electronic component 101 may have a lens 11 arranged on the wiring board 3 above the light-emitting device 5. The lens 11 has a lens portion 13 arranged above the light-emitting device 5 and a holding portion 14 for holding the lens portion 13. The lens 11 is arranged on the wiring board 3 via an adhesive 12 by the holding portion 14.

[0014] As shown in FIG. 5, the light-emitting device 5 has a light-emitting surface on its upper surface and is disposed on the wiring board 3 with the lower surface opposite to the upper surface as the mounting surface. The light-emitting device 5 has a light-emitting element 23. Further, the light-emitting device 5 may further include a light-transmissive member 24 disposed above the light-emitting element 23. The light-transmissive member 24 is, for example, a plate-like member having a substantially rectangular shape in a top view and is provided so as to cover the upper surface of the light-emitting element 23. The light-transmissive member 24 includes, for example, at least one selected from the group consisting of a wavelength conversion layer containing a wavelength conversion substance, a light diffusion layer containing a light diffusion member, and a transparent layer not containing a wavelength conversion substance and a light diffusion member. In the present embodiment, the light-transmissive member 24 includes a wavelength conversion layer 26 disposed on the upper surface of the light-emitting element 23 via an adhesive layer 27 and a light diffusion layer 25 disposed on the upper surface of the wavelength conversion layer 26. When the electronic component 101 includes a plurality of light-emitting devices 5, each of them may be individually lit, or they may be lit in groups. By individually lighting or lighting in groups each of the plurality of light-emitting devices 5, each light-emitting device 5 can be lit with a desired brightness.

[0015] In the present embodiment, the electronic component 101 includes two light-emitting devices 5, and each of the two light-emitting devices 5 includes a light-emitting element 23. Note that the electronic component 101 of the present disclosure is not limited to this, and for example, it may include one light-emitting device 5, and one light-emitting device 5 may include a plurality of light-emitting elements 23. When one light-emitting device 5 includes a plurality of light-emitting elements 23, the plurality of light-emitting elements 23 may be arranged at equal intervals, for example, in a first direction and a second direction intersecting the first direction in a top view. The plurality of light-emitting elements 23 are arranged, for example, in a 3×3, 5×5 or 7×9 pattern in a top view. The plurality of light-emitting elements 23 can be individually or grouped and lit by a control unit such as an IC driver.

[0016] The light-emitting element 23 has a semiconductor structure 22 and electrodes 21. The electrodes 21 have at least two electrodes, each functioning as either an anode or a cathode electrode. In the light-emitting device 5 shown in Figure 5, the electrodes 21 are located below the semiconductor structure 22. The semiconductor structure 22 may include a support substrate and a semiconductor layer placed on the support substrate. In this case, the support substrate, semiconductor layer, and electrodes 21 are arranged in that order.

[0017] The semiconductor structure 22 includes an n-side semiconductor layer, a p-side semiconductor layer, and an active layer sandwiched between the n-side and p-side semiconductor layers. The active layer may be a single quantum well (SQW) structure or a multiple quantum well (MQW) structure including multiple well layers. The semiconductor structure 22 includes multiple semiconductor layers made of nitride semiconductors. The nitride semiconductor is In x Al y Ga 1-x-y The semiconductor comprises all compositions in which the composition ratios x and y are varied within their respective ranges in the chemical formula N (0 ≤ x, 0 ≤ y, x + y ≤ 1). The emission peak wavelength of the active layer can be appropriately selected depending on the purpose. The active layer is configured to emit, for example, visible light or ultraviolet light.

[0018] The semiconductor structure 22 may include multiple light-emitting sections, each containing an n-side semiconductor layer, an active layer, and a p-side semiconductor layer. When the semiconductor structure 22 includes multiple light-emitting sections, each light-emitting section may include well layers with different emission peak wavelengths, or well layers with the same emission peak wavelength. Note that "same emission peak wavelength" includes cases where there is a variation of a few nanometers.

[0019] The wavelength conversion layer 26 converts the wavelength of at least a portion of the light from the light-emitting element 23. The wavelength conversion layer 26 is a plate-shaped member with a substantially rectangular shape when viewed from above. The wavelength conversion member included in the wavelength conversion layer 26 is, for example, a yttrium aluminum garnet-based phosphor (e.g., (Y,Gd)3(Al,Ga)5O 12 Ce), lutetium-aluminum-garnet phosphors (e.g., Lu3(Al,Ga)5O 12(Ce), CASN-based phosphors (e.g., CaAlSiN3:Eu), or SCASN-based phosphors (e.g., (Sr,Ca)AlSiN3:Eu) can be used.

[0020] The wavelength conversion layer 26 may be a resin material, ceramics, glass, etc., containing the above-mentioned wavelength conversion member, or a sintered body of the wavelength conversion member. Alternatively, the wavelength conversion layer 26 may be a resin layer containing the wavelength conversion member arranged on one surface of a molded body made of resin material, ceramics, glass, etc.

[0021] When the light-emitting device 5 emits white light, for example, a light-emitting element 23 that emits blue light and a wavelength conversion layer 26 that includes a wavelength conversion member that emits yellow light due to the light from the light-emitting element 23 can be combined.

[0022] The light diffusion layer 25 diffuses light that enters its interior. The light diffusion layer 25 is a plate-shaped member with a substantially rectangular shape when viewed from above. The light diffusion layer 25 is provided so as to cover the upper surface of the wavelength conversion layer 26. For example, the light diffusion layer 25 can be made of a resin material containing light-diffusing elements such as titanium oxide, barium titanate, aluminum oxide, or silicon oxide. In this embodiment, the planar shape of the light diffusion layer 25 is the same as the planar shape of the wavelength conversion layer 26. The planar shape of the light diffusion layer 25 may be larger or smaller than the planar shape of the wavelength conversion layer 26.

[0023] The outer edge of the light-transmitting member 24 may coincide with the outer edge of the light-emitting element 23 when viewed from above, or it may be located outside the outer edge of the light-emitting element 23. This reduces the amount of light emitted from the light-emitting element 23 that is taken out to the outside without passing through the light-transmitting member 24. The outer edge of the light-transmitting member 24 may also be located inside the outer edge of the light-emitting element 23 when viewed from above.

[0024] The adhesive layer 27 is positioned between the light-emitting element 23 and the light-transmitting member 24, and adheres the light-emitting element 23 and the light-transmitting member 24 together. The adhesive layer 27 is translucent to light emitted by the light-emitting element 23. As the material for the adhesive layer 27, for example, epoxy resin, acrylic resin, or cyclic polyolefin resin can be used. The adhesive layer 27 may also contain a light-scattering material.

[0025] The light-reflective member 28 has light-reflecting properties and reflects the light emitted by the light-emitting element 23. The light-reflective member 28 covers the sides of the light-emitting element 23 so that the upper surface of the light-emitting element 23 is exposed. In this embodiment, the light-reflective member 28 covers the sides of the light-emitting element 23, the sides of the wavelength conversion layer 26, and the sides of the light diffusion layer 25. The upper surface of the light diffusion layer 25 is exposed from the light-reflective member 28. The light-reflective member 28 also covers the sides and bottom surfaces of the semiconductor structure 22 of the light-emitting element 23. The light-reflective member 28 covers the sides of the electrodes 21 of the light-emitting element 23. The bottom surface of the electrodes 21 is exposed from the light-reflective member 28.

[0026] The light-reflective member 28 can be made of a resin material containing a light-reflective substance such as a white pigment. Examples of light-reflective substances include titanium dioxide, zinc oxide, magnesium oxide, magnesium carbonate, magnesium hydroxide, calcium carbonate, calcium hydroxide, calcium silicate, magnesium silicate, barium titanate, barium sulfate, aluminum hydroxide, aluminum oxide, zirconium oxide, silicon oxide, etc. It is preferable to use one of these alone or two or more of these in combination. Furthermore, it is preferable to use a resin material mainly composed of thermosetting resins such as epoxy resin, silicone resin, silicone-modified resin, and phenolic resin, or a resin material mainly composed of thermoplastic resins such as polyphthalamide resin, polybutylene terephthalate, and unsaturated polyester as the base material.

[0027] It should be noted that the light-emitting device in this disclosure is not limited to the light-emitting device 5 described above. For example, the light-emitting device may consist only of light-emitting elements. Furthermore, the light-emitting elements may include LEDs (light-emitting diodes) or LDs (semiconductor lasers).

[0028] The electronic component 101 may include a lens 11. The lens 11 includes a lens portion 13 and a holding portion 14 that holds the lens portion 13. The lens 11 is arranged on the wiring board 3 such that the lens portion 13 is positioned above the light-emitting device 5. The lens portion 13 is, for example, a Fresnel lens. The Fresnel lens is arranged such that, for example, the lower surface with irregularities faces the light-emitting device 5, allowing light emitted from the light-emitting device 5 to enter and exit from the flat upper surface. By using a Fresnel lens, the thickness of the lens 11 can be reduced. The lens 11 is preferably made of a light-transmitting resin such as polycarbonate resin, acrylic resin, silicone resin, or epoxy resin. The shape of the lens 11 is preferably circular or elliptical in plan view, but it may also be a polygon such as a square or hexagon.

[0029] For example, epoxy resin, acrylic resin, or cyclic polyolefin resin can be used as the adhesive 12 that connects the lens 11 holding portion 14 to the wiring board 3.

[0030] The wiring board 3 is a substrate on which the light-emitting device 5 can be arranged. The wiring board 3 comprises, for example, a substrate base material 2 containing an insulating material, and wiring 1 arranged on the surface of the substrate base material 2. The wiring board 3 may further arrange some of the wiring inside. In the wiring board 3, the wiring board 3 and the light-emitting device 5 are electrically connected by connecting the wiring 1 and the positive and negative electrodes 21 of the light-emitting device 5, for example, via a conductive adhesive.

[0031] The wiring 1 arranged on the surface of the substrate material 2 includes an external connection part that supplies current from the outside. The external connection part may be located on the top surface, bottom surface, or side surface connecting the top and bottom surfaces of the substrate material 2. In this embodiment, as shown in Figure 3, the external connection part is located on the bottom surface of the substrate material 2 (the bottom side of the light-emitting device 5). In the foreign matter detection process described later, it is preferable to detect foreign matter in the external connection part of the wiring 1. If there is foreign matter in the external connection part of the wiring board 3, for example, when placing the electronic component 101 on the mounting board via a bonding member, the wettability of the bonding member at the external connection part may decrease, and the electronic component 101 and the mounting board may not be sufficiently fixed. In this disclosure, the reliability of the electronic component 101 can be improved by performing a process to detect foreign matter in the external connection part.

[0032] As described above, in the electronic component 101 of this disclosure, multiple light-emitting devices 5 or multiple light-emitting elements 23 can be lit individually or in groups. When the size of the electronic component 101 is the same, the size of the external connection part (wiring 1) tends to decrease as the number of individually lit light-emitting devices 5 or light-emitting elements 23 increases. Furthermore, when the size of the external connection part (wiring 1) decreases, the influence of foreign matter at each external connection part tends to increase. The process or method for detecting foreign matter of this disclosure is particularly suitable for electronic component 101 equipped with multiple individually lit light-emitting devices 5 or light-emitting elements 23.

[0033] It is preferable to use an insulating material as the base material for the substrate base material 2. Furthermore, it is preferable to use a material for the substrate base material 2 that does not easily transmit light emitted from the light-emitting device 5 or ambient light, and has a certain level of mechanical strength. For example, the substrate base material 2 can be made from ceramics such as aluminum oxide, aluminum nitride, and mullite, or resins such as phenolic resin, epoxy resin, polyimide resin, BT resin (bismaleimidotriazine resin), and polyphthalamide.

[0034] Wiring 1 can be made of copper, iron, nickel, tungsten, chromium, aluminum, silver, gold, titanium, palladium, rhodium, or alloys thereof. Furthermore, the surface of wiring 1 may be provided with layers of silver, platinum, nickel, palladium, aluminum, rhodium, gold, or alloys thereof, from the viewpoint of wettability and / or light reflectivity of the conductive adhesive member. Wiring 1 preferably includes nickel plating on its surface. Including nickel plating on the surface of wiring 1 improves its corrosion resistance. Preferably, nickel plating, palladium plating, and gold plating are arranged on the surface of wiring 1 in this order.

[0035] (Method for manufacturing electronic components, and method for detecting foreign objects) The manufacturing method of the electronic component and the method for detecting foreign matter described herein will be explained below.

[0036] The method for manufacturing an electronic component according to this disclosure comprises the steps of preparing an electronic component 101 having a wiring board 3 with wiring 1, and detecting foreign matter on the surface of the wiring 1. The process for detecting foreign objects is, (1) Irradiate the surface of the wiring with a first light having an emission peak wavelength in the range of 350 nm to 495 nm, and the emission intensity of light with a wavelength of 500 nm or more in the emission spectrum being 5% or less of the emission intensity at the emission peak wavelength, and simultaneously acquire first image information by imaging the surface of the wiring. (2) Irradiate the surface of the wiring with a second light containing light with a wavelength of 500 nm or more, and acquire second image information by imaging the surface of the wiring. (3) Perform difference processing between the first image information and the second image information to obtain the third image information. (4) In the third image information, areas showing a brightness lower than a predetermined brightness reference value are determined to be foreign objects, and foreign objects are detected. including

[0037] The method for detecting foreign matter described herein is a detection method for detecting foreign matter on the surface of wiring on a wiring board. A detection method for detecting foreign matter on the surface of wiring on a wiring board is: (1) Irradiate the surface of the wiring with a first light having an emission peak wavelength in the range of 350 nm to 495 nm, and the emission intensity of light with a wavelength of 500 nm or more in the emission spectrum being 5% or less of the emission intensity at the emission peak wavelength, and simultaneously acquire first image information by imaging the surface of the wiring. (2) Irradiate the surface of the wiring with a second light containing light with a wavelength of 500 nm or more, and acquire second image information by imaging the surface of the wiring. (3) Perform difference processing between the first image information and the second image information to obtain the third image information. (4) In the third image information, areas showing a brightness lower than a predetermined brightness reference value are determined to be foreign objects, and foreign objects are detected. Includes.

[0038] The process for detecting foreign objects in this disclosure is carried out, for example, within a visual inspection device. The visual inspection device acquires image data corresponding to the captured image of the object and the image data after differential processing as image information, and performs detection of foreign objects from the image data. Preferably, the visual inspection device is capable of outputting the captured image of the object and the captured image after differential processing. This allows the presence or absence of foreign objects to be confirmed from the captured image by the human eye, making foreign object detection easier.

[0039] Foreign matter refers to substances that are unintentionally present in or on the surface of wiring 1. Examples include substances unintentionally included in the raw materials of wiring 1, substances unintentionally incorporated during the formation of wiring 1, and substances unintentionally adhering to the surface of wiring 1 after its formation. Foreign matter can also include components in other components besides wiring 1, such as resin components and metal components. For example, foreign matter may be nickel contained in plating, etc., adhering to the surface of wiring 1, or liquid components such as oil contained in the adhesive used to bond lens 11 and wiring substrate 3. Examples of adhesives include resin materials such as thermosetting resins, thermoplastic resins, and UV-curing resins. Specifically, examples include acrylic resins, polycarbonate resins, epoxy resins, modified epoxy resins, silicone resins, modified silicone resins, and hybrid silicone resins.

[0040] ·Process (1) Step (1) includes irradiating the surface of wiring 1 with first light having an emission peak wavelength in the range of 350 nm to 495 nm, and the emission intensity of light with a wavelength of 500 nm or more in the emission spectrum being 5% or less of the emission intensity at the emission peak wavelength, and acquiring first image information by imaging the surface of wiring 1.

[0041] "The emission intensity of light with a wavelength of 500 nm or more in the emission spectrum is 5% or less of the emission intensity at the emission peak wavelength" means that all light with a wavelength of 500 nm or more has an emission intensity of 5% or less of the emission intensity at the emission peak wavelength.

[0042] The first light has an emission intensity of light with a wavelength of 500 nm or more in its emission spectrum that is 5% or less, preferably 3% or less, and more preferably 1% or less, compared to the emission intensity at the emission peak wavelength.

[0043] The first light may have an emission intensity of light with a wavelength of 580 nm to 780 nm that is 3% or less, preferably 1% or less, and more preferably 0.1% or less, relative to the emission intensity at the emission peak wavelength. It is particularly preferable that the first light does not contain light with a wavelength of 580 nm to 780 nm.

[0044] The first light has an emission intensity of light with a wavelength of 330 nm or less in its emission spectrum, which is preferably 10% or less, more preferably 5% or less, and even more preferably 1% or less, compared to the emission intensity at the emission peak wavelength.

[0045] The first light is preferably blue light. Blue light is light having a wavelength mainly between 420 nm and 490 nm. More specifically, blue light is light having an emission peak wavelength in the range of 430 nm to 480 nm. The emission peak wavelength of the blue light is preferably between 440 nm and 470 nm, and more preferably between 445 nm and 460 nm. The emission intensity of light other than the light with a wavelength of 420 nm to 490 nm may be preferably 10% or less, more preferably 5% or less, and even more preferably 1% or less, relative to the emission intensity of the emission peak wavelength.

[0046] The light source emitting the first light is not particularly limited as long as it can emit light having the specified characteristics. Examples of the light source for the first light include light-emitting elements, mercury lamps, metal halide lamps, xenon lamps, excimer lamps, etc. Among these, it is preferable to use an LED.

[0047] The first light may be light directly emitted by a light source, or it may be light obtained by combining it with a wavelength conversion material such as a filter or a phosphor. For example, a blue first light may be obtained by combining a light source that emits ultraviolet light with a phosphor. Alternatively, a blue first light may be obtained by combining a light source that emits light containing blue light with a filter that transmits substantially only blue light. A light source that emits light containing blue light may be, for example, a light source that emits white light containing light with a wavelength of 500 nm or more. By combining such white light with a filter, both the first and second light can be irradiated with only one type of light source. That is, the first light is obtained when a filter is used, and the second light is obtained when a filter is not used.

[0048] The first image information can be obtained by photographing the wiring 1 on the underside of the wiring board 3 while the first light is irradiated onto the wiring 1.

[0049] ·Process (2) Step (2) includes irradiating the surface of wiring 1 with a second light containing light with a wavelength of 500 nm or more, and acquiring second image information by imaging the surface of wiring 1.

[0050] The second light may preferably include light with a wavelength of 580 nm to 780 nm, and more preferably with a wavelength of 630 nm to 760 nm.

[0051] The second light may include light outside the wavelength range of 580 nm to 780 nm. For example, the second light may include light in the wavelength range of 380 nm to less than 580 nm, and light in the wavelength range of over 780 nm and up to 900 nm.

[0052] In one embodiment, the second light may have an emission peak wavelength in the range of 580 nm to 780 nm, for example, in the range of 680 nm to 760 nm.

[0053] In another embodiment, the second light may have an emission peak wavelength outside the range of 580 nm to 780 nm.

[0054] If the second light has an emission peak wavelength outside the wavelength range of 580 nm to 780 nm, the second light may include light in the emission spectrum within the wavelength range of 580 nm to 780 nm that has an emission intensity of preferably 10% or more, more preferably 20% or more, and even more preferably 30% or more, relative to the emission intensity at the emission peak wavelength.

[0055] The second light source is preferably white light. White light refers to light that contains multiple wavelengths and exhibits a white color. White light is not strictly limited to light that contains all wavelength components of visible light, but may also contain light in a specific wavelength range. For example, white light may contain wavelength components from green to red. Examples of white light include daylight, neutral white, white, warm white, and incandescent light as defined in JIS Z 9112, as well as sunlight.

[0056] The light source emitting the second light is not particularly limited as long as it can emit light having the characteristics described above. Examples of the light source for the second light include light-emitting elements, fluorescent lamps, and sunlight. Among these, it is preferable to use an LED.

[0057] The light source emitting the second light may be light directly emitted by the light source, or it may be light obtained by combining a filter and wavelength conversion material such as a phosphor. For example, the second light may be obtained by combining a light source that emits light with a wavelength of less than 500 nm, such as ultraviolet light, with a phosphor.

[0058] The second image information can be obtained by photographing the underside of the wiring board 3 while irradiating the wiring 1 on the underside of the wiring board 3 with the second light.

[0059] The illumination of the first and second lights is preferably performed using ring illumination, which includes a light source for emitting the first light and a light source for emitting the second light. Ring illumination may be a ring-shaped light source or a configuration in which multiple light sources are arranged in a ring shape. By using a ring light source, uneven illumination can be reduced when illuminating the wiring.

[0060] The irradiation angles of the first and second light sources are preferably 45° to 90°, more preferably 60° to 90°, and even more preferably 70° to 90°. By bringing the irradiation angle closer to 90°, the wiring 1 can efficiently irradiate the light. Here, the irradiation angles of the first and second light sources refer to the angle formed by the straight line connecting the geometric centers of the light-emitting surfaces of the first and second light sources, the wiring 1, and the lower surface of the wiring board 3.

[0061] The combination of the first and second light sources is not particularly limited, but for example, the first light source in the process of acquiring the first image information may be blue light, and the second light source in the process of acquiring the second image information may be white light.

[0062] When acquiring the first and second image information, the optical axis of the camera may be preferably 45° to 90°, more preferably 60° to 90°, and even more preferably 70° to 90° with respect to the lower surface of the wiring board 3. By bringing the angle of the camera's optical axis with respect to the lower surface of the wiring board 3 closer to 90°, clearer image information can be obtained.

[0063] Steps (1) for acquiring first image information and step (2) for acquiring second image information are, for example, The upper surface of the lens 11 is held by suction, and the electronic component 101 is held so that the wiring 1 of the wiring board 3 is exposed downwards. In the process of acquiring the first image information, the first image information is acquired by irradiating the wiring 1 with first light from below the electronic component 101, In the process of acquiring second image information, the second image information is acquired by irradiating the wiring 1 with second light from below the electronic component 101, It may include.

[0064] For example, as shown in Figure 6, steps (1) and (2) may include: holding the electronic component 101 with the suction device 31 by adsorbing the upper surface of the lens 11 so that the wiring 1 of the wiring board 3 is exposed downwards; irradiating the held electronic component 101 with a first light using the illumination 32 and camera 33 positioned below it to acquire first image information; and irradiating with a second light to acquire second image information. In addition to using the suction device, a through hole may be provided in the inspection table on which the electronic component 101 is placed within the visual inspection apparatus, and the wiring 1 of the wiring board 3 may be imaged from below through the through hole. Alternatively, the electronic component 1 may be inverted so that the lens 11 is positioned downwards and the wiring 1 of the wiring board 3 is positioned upwards, and the wiring 1 may be imaged from above in the inverted state.

[0065] ·Process (3) Step (3) includes performing difference processing on the first image information and the second image information to obtain the third image information.

[0066] The differential processing can be performed, for example, using known image processing software included in the visual inspection device.

[0067] ·Process (4) Step (4) includes detecting foreign matter by determining that a portion of the third image information obtained above that shows a brightness lower than a preset brightness reference value is a foreign matter.

[0068] In the first image information, areas where foreign matter is present appear with relatively low brightness. Also, areas where the surface of wiring 1 is rough, such as areas where plating is rough, also appear with relatively low brightness. In other words, it is difficult to determine from the first image information whether the areas appearing with low brightness are due to foreign matter or surface roughness. On the other hand, in the second image information, areas where the surface of wiring 1 is rough appear with relatively low brightness, but areas where foreign matter is present appear with a brightness similar to areas where foreign matter is absent.

[0069] In the third image information obtained as a result of the difference processing between the first and second image information, no brightness difference appears in areas where the surface of wiring 1 is rough, and a brightness difference appears only in areas where foreign matter is present. Therefore, in the third image information, areas showing low brightness can be identified as foreign matter.

[0070] In one embodiment, the pre-set reference value for brightness may be, for example, a brightness 5% lower than the brightness corresponding to the median brightness when the brightness of the entire surface of the wiring 1 is represented in predetermined grayscale levels. That is, in the process of detecting foreign matter, a brightness 5% lower than the brightness corresponding to the median brightness when the brightness of the entire surface of the wiring 1 is represented in predetermined grayscale levels can be used as the reference value, and any part showing a brightness lower than this reference value can be determined to be foreign matter.

[0071] The reference value may be a brightness that is 10% lower or 15% lower than the brightness that corresponds to the median brightness when the brightness of the entire surface of wiring 1 is expressed in a predetermined number of gradations.

[0072] The predetermined number of gradations can be, for example, 128 or 256, with 256 being preferred.

[0073] In another embodiment, the preset reference value for brightness may be, for example, a brightness 20 levels lower than the brightness corresponding to the median brightness when the brightness of the entire surface of the wiring 1 is represented in 256 levels of brightness. That is, in the process of detecting foreign matter, when the brightness of the entire surface of the wiring 1 is represented in 256 levels of brightness, a brightness 20 levels lower than the brightness corresponding to the median brightness can be used as the reference value, and any part showing a brightness lower than this reference value can be determined to be foreign matter.

[0074] The reference value may be a gradation 30 steps lower or 40 steps lower than the gradation corresponding to the median value of the brightness when the brightness of the entire surface of wiring 1 is expressed in predetermined gradations.

[0075] The method for manufacturing electronic components according to this disclosure is particularly suitable for electronic components having a gold plating layer on the surface of wiring, where the foreign matter is nickel or an adhesive component, especially nickel.

[0076] The method for detecting foreign matter according to this disclosure is particularly suitable for detecting foreign matter, such as nickel or adhesive components, especially nickel, in wiring having a gold plating layer on its surface. [Examples]

[0077] (Fabrication of a light source device) Five types of light source devices, each including a wiring board and a light-emitting device, were fabricated. Specifically, multiple light-emitting devices were arranged in separate sections on a large wiring board as shown in the table below. Next, lenses were fixed to the wiring board using adhesive so as to cover each light-emitting device. Then, the large wiring board was cut into individual pieces using a dicing blade while applying water to the cutting area. This resulted in the light source devices shown in Figures 1 to 5.

[0078] (Foreign object detection test) As shown in Figure 6, the light source device obtained above was held by a suction device, and first image information was obtained by irradiating it with first light from the wiring board side, and then second image information was obtained by irradiating it with second light. The difference processing between the obtained first image information and second image information was performed using known image processing software within the visual inspection device. For the wiring portions in the obtained differential image information, the brightness was represented using 256 gradations. A gradation 20 gradations lower than the median brightness was used as a reference, and portions with a brightness lower than this reference were judged as foreign objects. If the total area of ​​the portions judged as foreign objects was 0.5% or more of the total area of ​​the wiring, it was judged as defective. The results are shown in the table below. First light: Blue light with an emission peak wavelength of approximately 455 nm. Second light: White light with an emission peak wavelength of approximately 450 nm, containing light with wavelengths of 500 nm to 700 nm.

[0079] As a comparative example, the first image obtained by irradiating with the first light was used to perform foreign body detection in the same manner as described above. The results are shown in the table below.

[0080] [Table 1]

[0081] From the results above, the defect rate was 27.48% when judged from the first image information, but it was 0.03% when judged from the difference image information. In order to check the cause of the difference in the defect rate, the wiring of the comparative example sample was examined, and it was confirmed that when judged from the first image information, areas with roughness on the wiring surface, such as plating roughness, were also judged as foreign matter. In other words, it was confirmed that the comparative example method judged samples that did not have foreign matter that could cause connection failure with the mounting board, etc., as defective, and defective samples were over-detected. On the other hand, in the example judged from the difference image information, there was no over-detection of plating roughness, etc., and it was confirmed that the presence of foreign matter was detected with high accuracy.

[0082] This disclosure includes the following aspects: [Section 1] A process for preparing an electronic component that includes a wiring board with wiring, The process includes detecting foreign matter on the surface of the wiring, The process for detecting the foreign object is: (1) Irradiate the surface of the wiring with first light having an emission peak wavelength in the range of 350 nm to 495 nm, and the emission intensity of light with a wavelength of 500 nm or more in the emission spectrum being 5% or less of the emission intensity at the emission peak wavelength, and acquire first image information by imaging the surface of the wiring. (2) Irradiate the surface of the wiring with a second light containing light with a wavelength of 500 nm or more, and acquire second image information by imaging the surface of the wiring. (3) Perform a difference processing on the first image information and the second image information to obtain the third image information. (4) In the third image information, the portion showing a brightness lower than a preset brightness reference value is determined to be the foreign object, and the foreign object is detected. A method for manufacturing electronic components, including [Section 2] The method for manufacturing an electronic component according to item 1, wherein in the step of acquiring the second image information, the light with a wavelength of 500 nm or more included in the second light is light with a wavelength of 580 nm or more and 780 nm or less. [Section 3] In the process of acquiring the first image information, the first light is blue light, A method for manufacturing an electronic component according to item 1 or 2, wherein in the step of acquiring the second image information, the second light is white light. [Section 4] A method for manufacturing an electronic component according to any one of items 1 to 3, wherein in the step of acquiring the first image information and the step of acquiring the second image information, the irradiation with the first light and the second light is performed using a ring illumination including a light source for irradiating the first light and a light source for irradiating the second light. [Section 5] A method for manufacturing an electronic component according to any one of items 1 to 4, wherein, in the step of detecting the foreign matter, when the brightness of the entire surface of the wiring is expressed in predetermined gradations, the brightness 5% lower than the brightness corresponding to the median brightness is set as the reference value, and any portion showing a brightness lower than the reference value is determined to be the foreign matter. [Section 6] A method for manufacturing an electronic component according to any one of items 1 to 4, wherein, in the step of detecting the foreign matter, when the brightness of the entire surface of the wiring is expressed in 256 levels, the level 20 levels lower in brightness from the level corresponding to the median brightness is set as the reference value, and any part showing a brightness lower than the reference value is determined to be the foreign matter. [Section 7] The method for manufacturing an electronic component according to any one of items 1 to 6, wherein the surface of the wiring is a gold plating layer. [Section 8] The aforementioned wiring board comprises a base material and the wiring arranged on the surface of the base material, including nickel plating. A method for manufacturing an electronic component according to any one of items 1 to 7, wherein in the step of detecting the foreign matter, the detected foreign matter is nickel. [Section 9] In the process of preparing the aforementioned electronic components, The aforementioned electronic component further comprises a lens having a lens portion and a holding portion for holding the lens portion. The method for manufacturing an electronic component according to any one of claims 1 to 8, wherein the holding portion of the lens is arranged on the wiring board via an adhesive. [Section 10] The method for manufacturing an electronic component according to item 9, wherein, in the step of detecting the foreign matter, the detected foreign matter is a substance contained in the adhesive. [Section 11] The steps for acquiring the first image information and acquiring the second image information are as follows: The upper surface of the lens is attracted, and the electronic component is held so that the wiring of the wiring board is exposed downwards. In the step of acquiring the first image information, the first image information is acquired by irradiating the wiring with first light from below the electronic component, In the process of acquiring the second image information, the second image information is acquired by irradiating the wiring with a second light from below the electronic component, A method for manufacturing an electronic component as described in item 9 or 10, including: [Section 12] A detection method for detecting foreign matter on the surface of wiring on a wiring board, (1) Irradiate the surface of the wiring with first light having an emission peak wavelength in the range of 350 nm to 495 nm, and the emission intensity of light with a wavelength of 500 nm or more in the emission spectrum being 5% or less of the emission intensity at the emission peak wavelength, and acquire first image information by imaging the surface of the wiring. (2) Irradiate the surface of the wiring with a second light containing light with a wavelength of 500 nm or more, and acquire second image information by imaging the surface of the wiring. (3) Perform a difference processing on the first image information and the second image information to obtain the third image information. (4) In the third image information, the portion showing a brightness lower than a preset brightness reference value is determined to be the foreign object, and the foreign object is detected. A detection method that includes this. [Section 13] The detection method according to item 12, wherein in the step of acquiring the second image information, the light with a wavelength of 500 nm or more contained in the second light is light with a wavelength of 580 nm or more and 780 nm or less. [Section 14] In the process of acquiring the first image information, the first light is blue light, The detection method according to item 12 or 13, wherein in the step of acquiring the second image information, the second light is white light. [Section 15] The detection method according to any one of items 12 to 14, wherein, in the step of detecting the foreign matter, when the brightness of the entire surface of the wiring is expressed in predetermined gradations, the brightness 5% lower than the brightness corresponding to the median brightness is set as the reference value, and any part showing a brightness lower than the reference value is determined to be the foreign matter. [Section 16] The detection method according to any one of items 12 to 14, wherein, in the step of detecting the foreign matter, when the brightness of the entire surface of the wiring is expressed in 256 gradations, the gradation 20 gradations lower in brightness from the gradation corresponding to the median brightness is set as the reference value, and any portion showing a brightness lower than the reference value is determined to be the foreign matter. [Explanation of Symbols]

[0083] 101…Electronic components 1…Wiring 2…Substrate material 3…Wiring board 5…Light-emitting device 11... Lens 12… Adhesive 13…Lens part 14...Holding part 21...Electrode 22… Semiconductor structures 23…Light-emitting element 24...Translucent member 25…Light Diffusion Layer 26...Wavelength conversion layer 27...adhesive layer 28…Light-reflective material 31...Adsorption device 32…Lighting 33... Camera

Claims

1. A process for preparing an electronic component that includes a wiring board with wiring, The process includes detecting foreign matter on the surface of the wiring, The process for detecting the foreign object is: (1) Irradiate the surface of the wiring with first light having an emission peak wavelength in the range of 350 nm to 495 nm, and the emission intensity of light with a wavelength of 500 nm or more in the emission spectrum being 5% or less of the emission intensity at the emission peak wavelength, and simultaneously acquire first image information by imaging the surface of the wiring. (2) Irradiate the surface of the wiring with a second light containing light with a wavelength of 500 nm or more, and acquire second image information by imaging the surface of the wiring. (3) Perform difference processing between the first image information and the second image information to obtain the third image information. (4) In the third image information, a portion showing a brightness lower than a preset brightness reference value is determined to be the foreign object, and the foreign object is detected. A method for manufacturing electronic components, including

2. The method for manufacturing an electronic component according to claim 1, wherein in the step of acquiring the second image information, the light with a wavelength of 500 nm or more included in the second light is light with a wavelength of 580 nm or more and 780 nm or less.

3. In the process of acquiring the first image information, the first light is blue light, The method for manufacturing an electronic component according to claim 1, wherein in the step of acquiring the second image information, the second light is white light.

4. The method for manufacturing an electronic component according to claim 1, wherein in the steps of acquiring the first image information and acquiring the second image information, the irradiation with the first light and the second light is performed using ring illumination including a light source for irradiating the first light and a light source for irradiating the second light.

5. The method for manufacturing an electronic component according to claim 1, wherein in the step of detecting the foreign matter, when the brightness of the entire surface of the wiring is expressed in predetermined gradations, the brightness 5% lower than the brightness corresponding to the median brightness is set as the reference value, and any portion showing a brightness lower than the reference value is determined to be the foreign matter.

6. The method for manufacturing an electronic component according to claim 1, wherein, in the step of detecting the foreign matter, when the brightness of the entire surface of the wiring is expressed in 256 levels, the level 20 levels lower in brightness from the level corresponding to the median brightness is set as the reference value, and any part showing a brightness lower than the reference value is determined to be the foreign matter.

7. The method for manufacturing an electronic component according to claim 1, wherein the surface of the wiring is a gold plating layer.

8. The aforementioned wiring board comprises a base material and the wiring, which is arranged on the surface of the base material and contains nickel. The method for manufacturing an electronic component according to claim 1, wherein the foreign matter detected in the step of detecting the foreign matter is nickel.

9. In the process of preparing the aforementioned electronic components, The aforementioned electronic component further comprises a lens having a lens portion and a holding portion for holding the lens portion. The method for manufacturing an electronic component according to any one of claims 1 to 8, wherein the holding portion of the lens is arranged on the wiring board via an adhesive.

10. The method for manufacturing an electronic component according to claim 9, wherein, in the step of detecting the foreign matter, the detected foreign matter is a substance contained in the adhesive.

11. The steps for acquiring the first image information and the second image information are as follows: The upper surface of the lens is attracted, and the electronic component is held so that the wiring of the wiring board is exposed downwards. In the step of acquiring the first image information, the first image information is acquired by irradiating the wiring with first light from below the electronic component, In the process of acquiring the second image information, the second image information is acquired by irradiating the wiring with a second light from below the electronic component, A method for manufacturing an electronic component according to claim 9, including the method described in claim 9.

12. A detection method for detecting foreign matter on the surface of wiring on a wiring board, (1) Irradiate the surface of the wiring with first light having an emission peak wavelength in the range of 350 nm to 495 nm, and the emission intensity of light with a wavelength of 500 nm or more in the emission spectrum being 5% or less of the emission intensity at the emission peak wavelength, and simultaneously acquire first image information by imaging the surface of the wiring. (2) Irradiate the surface of the wiring with a second light containing light with a wavelength of 500 nm or more, and acquire second image information by imaging the surface of the wiring. (3) Perform difference processing between the first image information and the second image information to obtain the third image information. (4) In the third image information, a portion showing a brightness lower than a preset brightness reference value is determined to be the foreign object, and the foreign object is detected. A detection method that includes this.

13. The detection method according to claim 12, wherein in the step of acquiring the second image information, the light with a wavelength of 500 nm or more included in the second light is light with a wavelength of 580 nm or more and 780 nm or less.

14. In the process of acquiring the first image information, the first light is blue light, The detection method according to claim 12, wherein in the step of acquiring the second image information, the second light is white light.

15. The detection method according to claim 12, wherein, in the step of detecting the foreign matter, when the brightness of the entire surface of the wiring is expressed in predetermined gradations, the brightness 5% lower than the brightness corresponding to the median brightness is set as the reference value, and any portion showing a brightness lower than the reference value is determined to be the foreign matter.

16. The detection method according to claim 12, wherein in the step of detecting the foreign matter, when the brightness of the entire surface of the wiring is expressed in 256 levels, the level 20 levels lower in brightness from the level corresponding to the median brightness is set as the reference value, and the portion showing a brightness lower than the reference value is determined to be the foreign matter.

Images