LED module and LED module mounting structure

An LED module includes a substrate having a main surface and a rear surface located opposite the main surface, a main surface electrode located on the main surface, a plurality of penetration electrodes connected to the main surface electrode and extending through the substrate, three or more LED chips arranged on the main surface electrode along a first direction, and a case arranged on the main surface to surround the main surface electrode. The LED chips include at least one LED chip that can emit red light, at least one LED chip that can emit green light and at least one LED chip that can emit blue light.

CROSS-REFERENCE TO RELATED APPLICATION

This application is based upon and claims the benefit of priority from Japanese Patent Application(s) No. 2011-161090, filed on Jul. 22, 2011, the entire contents of which are incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to an LED module and an LED module mounting structure.

BACKGROUND

FIG. 32shows one example of an LED module. The LED module900shown inFIG. 32has a structure in which three LED chips931,932and933are mounted on an elongated rectangular substrate910. A plurality of electrodes921,922,923and924are formed in the substrate910. The LED chips931,932and933are wire-bonded to the electrodes921,922and923, respectively. The electrode924is a so-called common electrode and is electrically connected to the LED chips931,932and933through a wire. The three LED chips931,932and933are surrounded by a case950. The case950has a substantially frame-like shape and is made of an opaque resin. The internal space of the case950is filled with a transparent resin (not shown). The LED module900is often referred to as a side view type LED module, which is mounted to a mounting substrate or the like by using a lower surface (shown inFIG. 32) extending in the longitudinal direction of the substrate910as a mounting surface. The LED chips931,932and933are configured to emit red light, green light and blue light, respectively. These three types of light emitted from the LED chips931,932and933are mixed with one another so that the LED module900can emit white light.

However, in recent years, there is an ever increasing demand for reduction in the size of the LED module900. For example, the width of the substrate910needs to be made smaller in order to reduce the projection height of the substrate910from the mounting substrate to which the LED module900is mounted. As a consequence, a space for accommodating the LED chips931,932and933becomes narrower. The space for accommodating the LED chips931,932and933includes not only an installation space of the LED chips931,932and933per se but also a space for arrangement of the wires bonded to the LED chips931,932and933and for arrangement of the portion of the common electrode924to which the wires are connected. Thus, the area allocated for the electrodes922and923in the substrate910is not considered insignificant at all. It is therefore not easy to reduce the width of the substrate910.

Alternatives to the side view type LED module as described above may include a top view type LED module, for which there is also a demand for reduction in the size of the top view type LED module.

SUMMARY

The present disclosure provides in some embodiments, an LED module having a reduced size.

According to a first aspect of the present disclosure, there is provided an LED module including: a substrate having a main surface and a rear surface located opposite the main surface; a main surface electrode formed on the main surface; a plurality of penetration electrodes connected to the main surface electrode and extending through the substrate; three or more LED chips arranged on the main surface electrode along a first direction; and a case arranged on the main surface to surround the main surface electrode, wherein the LED chips include at least one LED chip that can emit red light, at least one LED chip that can emit green light and at least one LED chip that can emit blue light.

In some embodiments, the main surface electrode has a portion located between the main surface and the case.

In some embodiments, the LED module further includes a plurality of wires, each of the wires being bonded to one of the LED chips and the main surface electrode.

In some embodiments, the LED module further includes: a rear surface electrode formed on the rear surface and connected to each of the penetration electrodes; and an insulating film formed on the rear surface.

In some embodiments, the wires have end portions overlapping with the rear surface electrode or the insulating film when viewed in a thickness direction of the substrate.

In some embodiments, when viewed in the thickness direction of the substrate, the insulating film is formed in a region of the rear surface other than a region where the rear surface electrode is formed.

In some embodiments, the rear surface electrode includes a plurality of mutually spaced-apart mounting pad portions, the insulating film includes a first band-like insulating portion extending in an elongated shape, and the first band-like insulating portion is located between two of the mounting pad portions.

In some embodiments, the rear surface includes an exposed portion exposed from the insulating film, the exposed portion being positioned in a marginal area of the rear surface along an extension direction of the first band-like insulating portion and the first band-like insulating portion being contiguous to the exposed portion when viewed in the thickness direction of the substrate.

In some embodiments, the insulating film includes a second band-like insulating portion extending in an elongated shape along a direction intersecting the extension direction of the first band-like insulating portion, the second band-like insulating portion being located between two of the mounting pad portions.

In some embodiments, the second band-like insulating portion reaches a peripheral end of the rear surface.

In some embodiments, the main surface electrode includes a first conductive portion and a plurality of second conductive portions insulated from the first conductive portion, and at least one of the LED chips is arranged on the first conductive portion.

In some embodiments, the first conductive portion includes a first die pad and a first wire bonding pad electrically connected to the first die pad, the first die pad and the first wire bonding pad being spaced apart from each other with a gap left therebetween, at least one of the LED chips is arranged on the first die pad, and at least one of the wires is bonded to the first wire bonding pad.

In some embodiments, the first wire bonding pad is spaced apart from the first die pad in a second direction intersecting the first direction.

In some embodiments, the first die pad is positioned between the second conductive portions and the first wire bonding pad.

In some embodiments, the first conductive portion includes a first circular pad electrically connected to the first wire bonding pad and overlapping with one of the penetration electrodes when viewed in the thickness direction of the substrate.

In some embodiments, the first circular pad has a portion located between the case and the substrate.

In some embodiments, the first conductive portion includes a band-like portion electrically connected to the first die pad.

In some embodiments, each of the second conductive portions includes a wire bonding wiring section to which one of the wires is bonded.

In some embodiments, one of the wires is bonded to each of the second conductive portions.

In some embodiments, each of the second conductive portions includes a circular wiring section electrically connected to the wire bonding wiring section and overlapping with one of the penetration electrodes when viewed in the thickness direction of the substrate.

In some embodiments, the circular wiring section is connected to the wire bonding wiring section.

In some embodiments, the circular wiring section has a portion located between the case and the substrate.

In some embodiments, the LED module further includes: a plurality of bonding layers located between each of the LED chips and the main surface electrode.

In some embodiments, at least one of the bonding layers is electrically conductive.

In some embodiments, at least one of the bonding layers has an insulation property.

In some embodiments, the LED module further includes: an adhesion layer located between the case and the substrate.

In some embodiments, one of the penetration electrodes overlaps with the case when viewed in the thickness direction of the substrate.

In some embodiments, the case has a surrounding surface surrounding the LED chips.

In some embodiments, the case has a case side surface facing the opposite side of a region surrounded by the surrounding surface.

In some embodiments, the substrate has a substrate side surface flush with the case side surface.

In some embodiments, the case has a bottom surface facing the main surface and connected to the surrounding surface and the case side surface.

In some embodiments, the bottom surface has a frame-like shape and extends flat from the surrounding surface to the case side surface.

In some embodiments, the surrounding surface is inclined with respect to the thickness direction of the substrate such that the surrounding surface makes an acute angle with the bottom surface.

In some embodiments, the LED chips are arranged on the first die pad.

In some embodiments, when viewed in the thickness direction of the substrate, at least one of the wires extends in a direction inclined with respect to the first direction and a direction orthogonal to the first direction.

In some embodiments, the first conductive portion includes a second die pad spaced apart from the first die pad and a third die pad spaced apart from the first die pad and the second die pad, and only one of the LED chips is arranged on each of the first to third die pad.

According to a second aspect of the present disclosure, there is provided an LED module mounting structure including: the LED module of the first aspect of the present disclosure; a mounting substrate; and a solder layer located between the mounting substrate and the rear surface.

According to a third aspect of the present disclosure, there is provided an LED module including: a substrate having a main surface; a main surface electrode formed on the main surface; a plurality of penetration electrodes connected to the main surface electrode and extending through the substrate; and a plurality of LED chips arranged on the main surface electrode along one direction, wherein distances between the LED chips range from 100 μm to 150 μm.

According to a fourth aspect of the present disclosure, there is provided an LED module including: a substrate including a main surface, a rear surface and a bottom surface, the main surface and the rear surface facing opposite sides of each other and being elongated rectangular in shape, and the bottom surface interconnecting long sides of the main surface and the rear surface and serving as a mounting surface of the LED module; at least one LED chip supported on the main surface of the substrate; and a wiring line formed on the substrate and electrically connected to the LED chip, wherein the substrate includes at least one through-hole extending from the main surface to the rear surface, and wherein the wiring line includes at least one pad formed on the main surface and electrically connected to the LED chip, a rear surface electrode formed on the rear surface and at least one penetration electrode formed on the inner surface of the through-hole to electrically interconnect the pad and the rear surface electrode.

In some embodiments, the wiring line is not formed on the bottom surface of the substrate.

In some embodiments, the number of said at least one LED chip is three and the three LED chips are arranged along a longitudinal direction of the main surface and spaced apart from one another.

In some embodiments, the number of said at least one through-hole is three and the number of said at least one penetration electrode is three.

In some embodiments, the LED module further includes: a first wire, wherein said at least one pad of the wiring line includes a bonding pad and one of the three LED chips and the bonding pad are interconnected via the first wire, and wherein one of the three through-holes and the bonding pad overlap with each other when viewed in a thickness direction of the substrate and one of the three penetration electrodes and the bonding pad are electrically connected to each other.

In some embodiments, said at least one pad of the wiring line includes two die bonding pads to which two of the three LED chips are die-bonded, the two die bonding pads overlapping with two of the three through-holes when viewed in the thickness direction of the substrate.

In some embodiments, the rear surface electrode includes two individual electrodes electrically connected to the two die bonding pads through two of the three penetration electrodes.

In some embodiments, the substrate includes a pair of side surfaces interconnecting both ends of the main surface in the longitudinal direction and both ends of the rear surface in the longitudinal direction, wherein two corner grooves extending in the thickness direction of the substrate to reach from the main surface to the rear surface are formed between the side surfaces and the bottom surface, and wherein the wiring line includes two corner groove wiring lines formed in the inner surfaces of the two corner grooves.

In some embodiments, the rear surface electrode includes an end portion common electrode connected to one of the two corner groove wiring lines and electrically connected to the three LED chips and an end portion individual electrode connected to the other of the two corner groove wiring lines and electrically connected to one of the three LED chips.

In some embodiments, the wiring line includes a rear surface junction wiring line formed in the rear surface to interconnect one of the three penetration electrodes, which is not electrically connected to the two individual electrodes, and the end portion common electrode.

In some embodiments, each of the corner grooves has a quarter-circular cross section.

In some embodiments, the LED module further includes: a reflector formed on the main surface and having a reflecting surface configured to surround the three LED chips; and a transparent resin portion filled in a region surrounded by the reflecting surface to cover the three LED chips.

In some embodiments, the LED module further includes: a second wire configured to interconnect one of the three LED chips and the bonding pad, wherein the second wire having a portion overlapping, when viewed in the thickness direction of the substrate, with one of the three LED chips to which the first wire is connected.

In some embodiments, the center of one of the three LED chips to which the first wire is connected is misaligned, when viewed in a transverse direction of the main surface, with the center of one of the three LED chips to which the second wire is connected.

In some embodiments, when viewed in the thickness direction of the substrate, one of the three through-holes includes a portion overlapping with one of the three LED chips to which the second wire is connected and a portion protruding from said one of the three LED chips.

In some embodiments, the LED module further includes: an insulating film covering the rear surface electrode.

In some embodiments, the insulating film covers the rear surface junction wiring line.

In some embodiments, the insulating film exposes at least a portion of each of the individual electrodes.

In some embodiments, the insulating film covers portions of the individual electrodes adjoining the rear surface junction wiring line.

In some embodiments, the insulating film exposes the end portion common electrode and the end portion individual electrode.

Other features and advantages of the present disclosure will become more apparent from the following description of embodiments given in conjunction with the accompanying drawings.

DETAILED DESCRIPTION

A first embodiment of the present disclosure will be described with reference toFIGS. 1 through 14.

An LED module mounting structure B1shown inFIG. 1includes an LED module A1, a mounting substrate871and a solder layer872.

The mounting substrate871is, e.g., a printed wiring substrate. The mounting substrate871includes, e.g., an insulating substrate and pattern electrodes (not shown) formed in the insulating substrate. The LED module A1is placed on the mounting substrate871. The solder layer872is located between the LED module A1and the mounting substrate871. The solder layer872bonds the LED module A1and the mounting substrate871together.

FIG. 2is a plan view of the LED module A1according to the present embodiment.FIG. 3is a plan view of the LED module A1ofFIG. 2with a case and an adhesion layer omitted.FIG. 4is a bottom view of the LED module A1according to the present embodiment.FIG. 5is a section view taken along line V-V inFIG. 2.FIG. 6is a section view taken along line VI-VI inFIG. 2.

The LED module A1shown in these figures is a top view type LED module. In other words, the LED module A1irradiates light in the thickness direction of the mounting substrate871. The LED module A1includes a substrate1, a main surface electrode2, a plurality of penetration electrodes31, a rear surface electrode4, a plurality of LED chips511,512and513, a plurality of bonding layers521,522and523, an sealing resin portion59, a case6, an adhesion layer71, an insulating film74and a plurality of wires81. InFIG. 2, the sealing resin portion59is omitted for the sake of understanding.FIG. 5corresponds to an enlarged view of the LED module A1shown inFIG. 1. InFIG. 1, the bonding layers521,522and523and the adhesion layer71are omitted for the sake of understanding. InFIGS. 2 and 3, the bonding layers522and523are omitted. The dimension of the LED module A1in the X and Y directions is, e.g., approximately 1.6 mm to 1.8 mm.

The LED chips511,512and513are light sources of the LED module A1. Each of the LED chips511,512and513has a structure in which a p-type semiconductor layer, an n-type semiconductor layer and an active layer are laminated one above another. The active layer is located between the p-type semiconductor layer and the n-type semiconductor layer. In the present embodiment, the LED chip511emits red light, the LED chip512emits green light and LED chip513emits blue light. The LED chips511,512and513are arranged along the X direction. The distances between the LED chips511and512and between the LED chips512and513may range from 100 μm to 150 μm.

The substrate1has a rectangular shape in a plan view. The substrate1is made of, e.g., a glass epoxy resin. The substrate1includes a main surface11, substrate side surfaces12and a rear surface13. The main surface11and the rear surface13are located opposite one another and face opposite directions. The substrate side surfaces12face one side in the X direction or one side in the Y direction. The substrate side surfaces12are connected to both the main surface11and the rear surface13. The main surface11, the substrate side surfaces12and the rear surface13are flat. The solder layer872is located between the rear surface13and the mounting substrate871.

The main surface electrode2is formed on the main surface11. The main surface electrode2includes a first conductive portion24and a plurality of second conductive portions25. The main surface electrode2is formed by laminating copper, nickel and gold one above another. This holds true for the penetration electrodes31and the rear surface electrode4to be described later.

At least one of the LED chips511,512and513is arranged in the first conductive portion24. The first conductive portion24includes a die pad241, a wire bonding pad242, a circular pad243and band-like portions244and245.

The die pad241has a rectangular shape. At least one of the LED chips511,512and513is arranged in the die pad241. In the present embodiment, all the LED chips511,512and513are arranged in the die pad241.

The wire bonding pad242has a rectangular shape. In the present embodiment, the wire bonding pad242is formed into a rectangular shape such that the long side thereof extends in the X direction. At least one of the wires81is bonded to the wire bonding pad242. In the present embodiment, two of the wires81are bonded to the wire bonding pad242. The die pad241is spaced apart from the wire bonding pad242with a gap left therebetween. More specifically, the wire bonding pad242is spaced apart from the die pad241in the Y direction. When viewed in the direction Z, the lengths of the wires81range, e.g., from 0.4 mm to 0.6 mm.

The circular pad243has a circular shape when viewed in the Z direction. In the present embodiment, the circular pad243is located on the same side as the wire bonding pad242with respect to the die pad241. The circular pad243is located on one side in the X direction with respect to the wire bonding pad242. The circular pad243is electrically connected to the die pad241and the wire bonding pad242.

The band-like portion244extends in a band shape along the Y direction. The band-like portion244is electrically connected to the die pad241. In the present embodiment, the band-like portion244is electrically connected to the circular pad243. The band-like portion244is connected to the die pad241and the circular pad243.

The band-like portion245extends in a band shape along the X direction. The band-like portion245is electrically connected to the wire bonding pad242. In the present embodiment, the band-like portion245is electrically connected to the circular pad243. The band-like portion245is connected to the wire bonding pad242and the circular pad243. As the band-like portion245becomes thinner, the exposed area of the main surface11grows larger. If the reflectance of the main surface11is higher than that of the band-like portion245, the increase in the exposed area of the main surface11assists in increasing the intensity of light traveling in the Z direction of the LED module A1.

As set forth above, the die pad241, the wire bonding pad242, the circular pad243and the band-like portions244and245are electrically connected to one another.

The plurality of (three, in the present embodiment) second conductive portions25are insulated from the first conductive portion24. One of the wires81is bonded to each of the second conductive portions25. The die pad241is positioned between two of the second conductive portions25. The die pad241is positioned between the rest of the second conductive portions25and the wire bonding pad242.

Each of the second conductive portions25includes a wire bonding wiring section251and a circular wiring section252.

The wire bonding wiring section251has a rectangular shape. One of the wires81is bonded to the wire bonding wiring section251. The die pad241is spaced apart from the wire bonding wiring section251with a gap left therebetween. More specifically, the wire bonding wiring section251is spaced apart from the die pad241in the Y direction.

The circular wiring section252has a circular shape when viewed in the Z direction. The circular wiring section252is arranged at one side in the X direction with respect to the wire bonding wiring section251. The circular wiring section252is electrically connected to the wire bonding wiring section251.

Each of the plurality of (five, in the present embodiment) wires81is bonded to one of the LED chips511,512and513and the main surface electrode2. Each of the wires81is made of gold, silver or copper. In the present embodiment, each of the wires81is made of gold. When viewed in the thickness Z direction of the substrate1, the respective wires81extend in the directions inclined with respect to the X direction and the Y direction. The height of each of the wires81from the LED chips511,512and513ranges, e.g., from 110 μm to 130 μm.

The bonding layer521is located between the LED chip511and the main surface electrode2. In the present embodiment, the bonding layer521is located between the LED chip511and the die pad241(the first conductive portion24). The bonding layer521serves to bond the LED chip511to the main surface electrode2(the die pad241or the first conductive portion24in the present embodiment). The bonding layer521is electrically conductive. For example, silver paste is used in forming the electrically conductive bonding layer521. Since the bonding layer521is electrically conductive, the LED chip511and the main surface electrode2(the die pad241or the first conductive portion24in the present embodiment) are electrically connected to each other through the bonding layer521. When viewed in the direction Z, the bonding layer521occupies a wider area than the LED chip511occupies. If the bonding layer521has a circular shape when viewed in the Z direction, the diameter of the circle is, e.g., approximately 1.5 to 2 times as large as the length of one side of the tetragon defining the LED chip511.

The bonding layer522is located between the LED chip512and the main surface electrode2. In the present embodiment, the bonding layer522is located between the LED chip512and the die pad241(the first conductive portion24). The bonding layer522serves to bond the LED chip512to the main surface electrode2(the die pad241or the first conductive portion24in the present embodiment). In the present embodiment, the bonding layer522has an insulation property.

The bonding layer523is located between the LED chip513and the main surface electrode2. In the present embodiment, the bonding layer523is located between the LED chip513and the die pad241(the first conductive portion24). The bonding layer523serves to bond the LED chip513to the main surface electrode2(the die pad241or the first conductive portion24in the present embodiment). In the present embodiment, the bonding layer523has an insulation property.

The rear surface electrode4is formed on the rear surface13. The rear surface electrode4is a mounting electrode. The solder layer872(seeFIG. 1) is located between the rear surface electrode4and the mounting substrate871. The rear surface electrode4includes a plurality of (four, in the present embodiment) mounting pad portions41.

The mounting pad portions41have a rectangular shape. Needless to say, the shape of the mounting pad portions41is not limited to a rectangular shape. The mounting pad portions41are spaced apart from one another.

The penetration electrodes31extend through the substrate1. More specifically, each of the penetration electrodes31extends from the main surface11to the rear surface13through the substrate1. The penetration electrodes31cover the inner surfaces of through-holes formed in the substrate1. In the present embodiment, each of the penetration electrodes31has a film-like shape. Therefore, each of the penetration electrodes31has a cylindrical shape extending in the Z direction. In the present embodiment, a resin is filled in the space surrounded by each of the penetration electrodes31. Each of the penetration electrodes31is connected to the main surface electrode2and the rear surface electrode4. More specifically, the circular pad243is connected to one of the penetration electrodes31and overlaps with one of the penetration electrodes31when viewed in the direction Z. Each of the circular wiring sections252is connected to one of the penetration electrodes31. When viewed in the direction Z, the circular wiring sections252overlap with the penetration electrodes31.

The insulating film74is formed on the rear surface13. The insulating film74is a resist layer and referred to as a solder resist. The insulating film74serves to prevent the solder layer872from adhering to the rear surface13. In the present embodiment, when viewed in the thickness direction Z of the substrate1, the insulating film74is formed in the region on the rear surface13other than the region where the rear surface electrode4is formed. When viewed in the thickness direction Z of the substrate1, the end portion of each of the wires81overlaps with the insulating film74or the rear surface electrode4.

The insulating film74includes a plurality of (two, in the present embodiment) first band-like insulating portions741and a plurality of (two, in the present embodiment) second band-like insulating portions742.

Each of the first band-like insulating portions741extends in an elongated shape. In the present embodiment, each of the first band-like insulating portions741extends in the X direction. Each of the first band-like insulating portions741is located between two of the mounting pad portions41. More specifically, the first band-like insulating portion741arranged at the left side inFIG. 4is located between the left two mounting pad portions41. On the other hand, the first band-like insulating portion741arranged at the right side inFIG. 4is located between the right two mounting pad portions41. None of the first band-like insulating portions741reaches the peripheral end17of the rear surface13. In other words, an exposed portion15is positioned in the marginal area of the rear surface13in the extension direction (the X direction in the present embodiment) of the first band-like insulating portion741arranged at the left side inFIG. 4. The first band-like insulating portion741arranged at the left side inFIG. 4is contiguous to the exposed portion15. The reason for forming the exposed portion15in the substrate1is that an insulating film elongated in the X direction is not formed in the substrate1′ to be described later in order to prevent the substrate1′ from being bent. Similarly, an exposed portion15is positioned in the marginal area of the rear surface13along the extension direction (the X direction in the present embodiment) of the first band-like insulating portion741arranged at the right side inFIG. 4. The first band-like insulating portion741arranged at the right side inFIG. 4is contiguous to the exposed portion15. The reason for forming the exposed portion15in the substrate1is that an insulating film elongated in the direction X is not formed in the substrate1′. If the insulating film elongated in the direction X is not formed in the substrate1′, the substrate1′ can be prevented from being bent.

Each of the second band-like insulating portions742extends in an elongated shape. Each of the second band-like insulating portions742extends in the direction intersecting the extension direction of each of the first band-like insulating portions741. In the present embodiment, each of the second band-like insulating portions742extends in the direction Y. Each of the second band-like insulating portions742located between two of the mounting pad portions41. More specifically, the second band-like insulating portion742arranged at the upper side inFIG. 4located between the upper two mounting pad portions41. On the other hand, the second band-like insulating portion742arranged at the lower side inFIG. 4is located between the lower two mounting pad portions41. Each of the second band-like insulating portions742reaches the peripheral end17of the rear surface13.

The case6is arranged on the main surface11. The case6surrounds the LED chips511,512and513. In the present embodiment, the case6has a frame-like shape. The case6is made of an insulating material. Examples of the insulating material include polyphthalamide (PPA), liquid crystal polymer (LCP), silicon resin and epoxy resin. The case6may have a white color, a black color or a color other than white or black. The main surface electrode2is located between the case6and the main surface11. More specifically, the circular pad243is interposed between the case6and the main surface11. Moreover, the circular wiring sections252are located between the case6and the main surface11. If the main surface electrode2is reliably interposed between the case6and the main surface11, the case6can be prevented from being inclined with respect to the main surface11. When viewed in the Z direction, the case6overlaps with one of the penetration electrodes31.

The case6includes a surrounding surface61, a case side surface62and a bottom surface63.

The surrounding surface61surrounds the LED chips511,512and513. The surrounding surface61is inclined with respect to the thickness direction (Z direction) of the substrate1so as to make an acute angle with the bottom surface63. The inclination angle of the surrounding surface61with respect to the bottom surface63ranges, e.g., from 80 degrees to 85 degrees.

The case side surface62faces away from the region surrounded by the surrounding surface61. The shortest distance between the case side surface62and the surrounding surface61ranges, e.g., from 50 μm to 100 μm. The case side surface62and the substrate side surface12are flush with each other.

The bottom surface63faces the main surface11. The bottom surface63has a frame-like shape. The bottom surface63extends flat from the surrounding surface61to the case side surface62. The main surface electrode2is located between the bottom surface63and the main surface11. More specifically, the circular pad243is located between the bottom surface63and the main surface11. In addition, the circular wiring sections252are located between the bottom surface63and the main surface11.

The adhesion layer71attaches the case6to the main surface11. The adhesion layer71serves to fix the case6to the substrate1. The adhesion layer71is located between the case6and the substrate1. More specifically, the adhesion layer71is located between the main surface11and the bottom surface63. The adhesion layer71is formed by, e.g., curing a liquid adhesive agent. Examples of the liquid adhesive agent include a UV-based adhesive agent and an acryl-based adhesive agent.

The sealing resin portion59is arranged in the region surrounded by the case6. The sealing resin portion59covers the main surface11, the main surface electrode2, the LED chips511,512and513, the bonding layers521,522and523, the surrounding surface61and the adhesion layer71. The sealing resin portion59is made of a transparent resin or a resin transmitting the light emitted from the LED chips511,512and513.

Next, a brief description will be made on a manufacturing method of the LED module A1. Components similar to or identical with those described above will be designated by similar reference symbols.

FIG. 7is a plan view illustrating one step of a manufacturing process of manufacturing the LED module A1.FIG. 8is a sectional view taken along line VIII-VIII inFIG. 7. In these figures, there is shown an intermediate product881manufactured in the manufacturing process of the LED module A1. The substrate1′ of the intermediate product881is diced later into a plurality of substrates1. In the intermediate product881, the LED chips511,512and513stated above are previously arranged on the substrate1′.

FIG. 9is a sectional view illustrating one step of a method for forming a case6′. The case6′ is diced later into a plurality of cases6. As shown inFIG. 9, a first mold891and a second mold892are used in forming the case6′. A resin material is poured into a space between the first mold891and the second mold892in a state where the first mold891and the second mold892are combined together. The case6′ is obtained by curing the resin material.

Next, as shown inFIGS. 10 and 11, the case6′ is bonded to the substrate1′ through the use of the adhesion layer71(not shown inFIGS. 10 and 11).

Subsequently, as shown inFIGS. 12 and 13, the sealing resin portion59is formed and then the case6′ and the substrate1′ are together diced by means of dicing blades895. The LED module A1is completed through the steps set forth above.

Next, description will be made on the operations and effects of the present embodiment.

The LED module A1includes a plurality of penetration electrodes31. Each of the penetration electrodes31is connected to the main surface electrode2and the rear surface electrode4and extends through the substrate1. With this configuration, no electrode for electrically connecting the main surface electrode2and the rear surface electrode4needs to be formed on the substrate side surface12of the substrate1. For that reason, no extra space for guiding the main surface electrode2to the substrate side surface12needs to be provided on the main surface11, which results in the reduction in size of the main surface11. The reduction in size of the main surface11assists in reducing the size of the LED module A1.

Unlike the present embodiment, it can be thought that a junction electrode exposed on the substrate1in the direction orthogonal to the thickness direction Z is formed to electrically connect the main surface electrode2and the rear surface electrode4. The junction electrode may be formed in a semicircular groove depressed from the substrate side surface12. The semicircular groove may be formed by bisecting a circular hole formed in the substrate1′. The prior art may have a problem in forming two LED modules A1while reducing the size of the circular hole formed in the substrate F. For example, if the circular hole is formed into a small size, the width of the frame-like portion of the case needs to be reduced. In this case, the cross-sectional area of the resin flow space interposed between the first mold891and the second mold892becomes smaller, and the resin material cannot spread throughout the space. In view of this, the size of the circular hole needs to be set larger than a specific value. However, if the size of the main surface11is reduced while setting the size of the circular hole larger than the specific value, the junction electrode formed in the semicircular hole gets closer to the other junction electrode adjacent thereto. If the junction electrodes get close enough together such that they are adjoining, it is likely that, when mounting the LED module, the junction electrodes will be short-circuited through a solder layer.

On the other hand, since the junction electrode is not formed in the LED module A1, the size of the LED module A1can be reduced without suffering from the above-described problem.

In the LED module A1, the end portions of the wires81overlap with the rear surface electrode4or the insulating film74when viewed in the thickness direction (Z direction) of the substrate1. With this configuration, the rear surface electrode4or the insulating film74is positioned in the region of the rear surface13overlapping with the end portions of the wires81when viewed in the Z direction.FIG. 14is a partially-enlarged sectional view showing a vicinity of the rear surface13of the substrate1′ during a step of bonding the wires81in the LED module manufacturing process. In the present embodiment, ultrasonic waves flowing through the wires81when bonding the wires81to the LED chips511,512and513or the main surface electrode2can efficiently flow toward a stage882via the rear surface electrode4or the insulating film74, which results in a reliable bond of the wires81to the LED chips511,512and513or the main surface electrode2.

Supposing that the semicircular groove (the circular hole prior to dicing the substrate1′) is formed in the substrate1, the liquid adhesive agent forming the adhesion layer71may be dropped into the circular hole when bonding the case6′ to the substrate F. In the prior art, a recess depressed from the bottom surface63is formed in the case6in order to prevent the liquid adhesive agent from dropping into the circular hole. In order to form the recess depressed from the bottom surface63in the case6, a mold for forming the recess needs to be prepared, which results in wasted effort and cost. In the present embodiment, however, the hole into which the liquid adhesive agent may drop is not formed in the substrate F. Accordingly, the recess depressed from the bottom surface63need not be formed in the case6. This eliminates the need to perform additional processes on the second mold892. With the present embodiment, the efforts and costs required in manufacturing the second mold892can be reduced. Since the recess depressed from the bottom surface63needs not to be formed in the case6, the case6of the LED module A1can be configured to have the bottom surface63extending flat from the surrounding surface61to the case side surface62.

It is assumed that the LED chips511,512and513are respectively arranged on individual die pads spaced apart from one another. The individual die pads need to be spaced apart from one another by a distance of, e.g., about 75 μm. Therefore, when the LED chips511,512and513are respectively arranged on the individual die pads spaced apart from one another, distances between the individual die pads need to be secured. This makes it difficult to arrange the LED chips511,512and513to come to close to one another. In the present embodiment, however, the LED chips511,512and513are arranged on the single die pad241. It is therefore unnecessary to secure distances between die pads, which results in a reduction in distances between the LED chips511,512and513. The reduction in distances between the LED chips511,512and513assists in reducing the size of the LED module A1.

In the LED module A1, the respective wires81extend in the directions inclined with respect to the X direction and the Y direction orthogonal to the X direction when viewed in the thickness direction Z of the substrate1. As compared with a case where the respective wires81extend straightforward, this configuration assists in reducing the size of the LED module A1in the Y direction.

In the LED module A1, the die pad241is spaced apart from the wire bonding pad242with a gap left therebetween. With this configuration, even if the liquid resin material forming the bonding layers522and523flows from the die pad241toward the wire bonding pad242when forming the bonding layers522and523, the liquid resin material can be kept between the die pad241and the wire bonding pad242. Accordingly, the bonding layers522and523can be prevented from covering the wire bonding pad242, and the region of the wire bonding pad242to be bonded with the wires81can be exposed in a reliable manner without being covered by the bonding layers522and523.

A second embodiment of the present disclosure will be described with reference toFIGS. 15 through 18.

FIG. 15is a plan view showing an LED module according to the second embodiment of the present disclosure.FIG. 16is a plan view of the LED module ofFIG. 15with a case and an adhesion layer omitted.FIG. 17is a bottom view of the LED module according to the second embodiment.FIG. 18is a sectional view taken along line XVIII-XVIII inFIG. 15.

The LED module A2shown in these figures includes a substrate1, a main surface electrode2, a plurality of penetration electrodes31, a rear surface electrode4, a plurality of LED chips511,512and513, a plurality of bonding layers521,522and523, a sealing resin portion59, a case6, an adhesion layer71, an insulating film74and a plurality of wires81. The configurations of the substrate1, the LED chips511,512and513, the bonding layers521,522and523, the sealing resin portion59, the case6, the adhesion layer71, the insulating film74and the wires81are the same as those of the LED module A1described above. Therefore, no description will be made in this regard. InFIG. 15, the sealing resin portion59is omitted for the sake of understanding.

The main surface electrode2is located on the main surface11. The main surface electrode2includes a first conductive portion24and a plurality of second conductive portions25. The second conductive portions25are the same as those of the LED module A1described above. Therefore, no description will be made in this regard.

At least one of the LED chips511,512and513is arranged in the first conductive portion24. In the present embodiment, the LED chips511,512and513are arranged in the first conductive portion24. The first conductive portion24includes a plurality of (three) die pads241a,241band241c, a plurality of (three) wire bonding pads242a,242band242c, a plurality of (three) circular pads243a,243band243cand a plurality of (three) band-like portions244a,244band244c.

The die pad241ahas a rectangular shape. The LED chip511is arranged in the die pad241a.

The wire bonding pad242ahas a rectangular shape. In the present embodiment, none of the wires81is bonded to the wire bonding pad242a. The die pad241ais spaced apart from the wire bonding pad242awith a gap left therebetween. The wire bonding pad242ais spaced apart from the die pad241ain the Y direction.

The circular pad243ahas a circular shape when viewed in the Z direction. The circular pad243ais electrically connected to the die pad241aand the wire bonding pad242a.

The band-like portion244aextends in a band shape along the Y direction. The band-like portion244ais electrically connected to the die pad241a. In the present embodiment, the band-like portion244ais electrically connected to the circular pad243a. The band-like portion244ais connected to the die pad241aand the circular pad243a.

The die pad241a, the wire bonding pad242a, the circular pad243aand the band-like portion244aform a single body.

The die pad241b, the wire bonding pad242b, the circular pad243band the band-like portion244bare substantially the same as the die pad241a, the wire bonding pad242a, the circular pad243aand the band-like portion244a, respectively.

The die pad241bhas a rectangular shape. The LED chip512is arranged on the die pad241b.

The wire bonding pad242bhas a rectangular shape. In the present embodiment, one of the wires81is bonded to the wire bonding pad242b. The die pad241bis spaced apart from the wire bonding pad242bwith a gap left therebetween. The wire bonding pad242bis spaced apart from the die pad241bin the Y direction.

The circular pad243bhas a circular shape when viewed in the Z direction. The circular pad243bis electrically connected to the die pad241band the wire bonding pad242b.

The band-like portion244bextends in a band shape along the Y direction. The band-like portion244bis electrically connected to the die pad241b. In the present embodiment, the band-like portion244bis electrically connected to the circular pad243b. The band-like portion244bis connected to the die pad241band the circular pad243b.

The die pad241b, the wire bonding pad242b, the circular pad243band the band-like portion244bform a single body.

The die pad241c, the wire bonding pad242c, the circular pad243cand the band-like portion244care substantially the same as the die pad241a, the wire bonding pad242a, the circular pad243aand the band-like portion244a, respectively.

The die pad241chas a rectangular shape. The LED chip513is arranged on the die pad241c.

The wire bonding pad242chas a rectangular shape. In the present embodiment, one of the wires81is bonded to the wire bonding pad242c. The die pad241cis spaced apart from the wire bonding pad242cwith a gap left therebetween. The wire bonding pad242cis spaced apart from the die pad241cin the Y direction.

The circular pad243chas a circular shape when viewed in the Z direction. The circular pad243cis electrically connected to the die pad241cand the wire bonding pad242c.

The band-like portion244cextends in a band shape along the Y direction. The band-like portion244cis electrically connected to the die pad241c. In the present embodiment, the band-like portion244cis electrically connected to the circular pad243c. The band-like portion244cis connected to the die pad241cand the circular pad243c.

The die pad241c, the wire bonding pad242c, the circular pad243cand the band-like portion244cform a single body.

The die pads241a,241band241care spaced apart from one another.

The rear surface electrode4is the same as that of the LED module A1except that the number of the mounting pad portions41is six. Therefore, no description will be made on the rear surface electrode4.

Next, description will be made on the operations and effects of the present embodiment.

Like the LED module A1, the LED module A2is suitable for size reduction.

In the LED module A2, the end portions of the wires81overlap with the rear surface electrode4or the insulating film74when viewed in the thickness direction Z of the substrate1. With this configuration, as described above with respect to the LED module A1, it is possible to reliably bond the wires81.

With the present embodiment, as described above with respect to the LED module A1, the efforts and costs required in manufacturing the second mold892can be reduced. Since the recess depressed from the bottom surface63need not be formed in the case6, the case6of the LED module A2can be configured to have the bottom surface63extending flat from the surrounding surface61to the case side surface62.

FIGS. 19 through 23show an LED module according to a first reference example of the present disclosure. The LED module101of the present reference example includes a substrate200, a wiring line300, three LED chips401,402and403and a transparent resin portion700. The LED module101is a so-called side view type LED module mounted to, e.g., a mounting substrate801as shown inFIG. 23. In the present reference example, the LED module101may have an x-direction dimension of about 3.0 mm, a y-direction dimension of about 0.43 mm and a z-direction dimension of about 1.3 mm.

The substrate200is an insulating substrate made of, e.g., a glass epoxy resin. The substrate200has an elongated rectangular shape, the longitudinal direction thereof running in the x-direction, the transverse direction thereof running in the y-direction and the thickness direction thereof running in the z-direction. The substrate200includes a main surface201, a rear surface202, a bottom surface203and two side surfaces204. A pair of through-holes211and212and a pair of corner grooves221and222are formed in the substrate200. As shown inFIGS. 19 and 22, the through-holes211and212are arranged closer to the side opposite the bottom surface203in the y-direction. In the present reference example, the substrate200may have an x-direction dimension of about 3.0 mm, a y-direction dimension of about 0.43 mm and a z-direction dimension of about 0.5 mm.

The through-holes211and212penetrate through the substrate200in the z-direction and extend from the main surface201to the rear surface202. The corner grooves221and222are disposed between the side surfaces204and the bottom surface203and extend in the z-direction. Each of the corner grooves221and222extends from the main surface201to the rear surface202and has a quarter-circular cross section.

The wiring line300serves as an electric power supply path to the three LED chips401,402and403. The wiring line300includes die bonding pads301,302and303, two quarter-circular arc portions321, a main surface junction wiring line322, a branch wiring line323, corner groove wiring lines341and342, penetration electrodes351and352and a rear surface electrode370. The wiring line300has a structure formed by, e.g., laminating a Cu layer, a Ni layer and an Au layer one above another.

The die bonding pads301,302and303are arranged along the x-direction. The LED chips401,402and403are die-bonded to the die bonding pads301,302and303. Each of the die bonding pads301and302is formed by combining a square portion and a circular portion. The circular portions of the die bonding pads301and302are arranged opposite each other in the x-direction. The die bonding pad303includes a square portion and a band-like portion extending from the square portion in the x-direction.

The quarter-circular arc portions321are formed near the regions of the main surface201connected to the corner grooves221and222. The main surface junction wiring line322extends in a band shape along the x-direction from the quarter-circular arc portion321formed near the corner groove221. The main surface junction wiring line322is arranged near one end of the main surface201in the y-direction. The branch wiring line323extends in the y-direction from the main surface junction wiring line322between the die bonding pads301and302.

The corner groove wiring lines341and342are formed to cover the inner surfaces of the corner grooves221and222of the substrate200. The corner groove wiring lines341and342extend from the main surface201to the rear surface202. The penetration electrodes351and352are formed in a cylindrical shape on the inner surfaces of the through-holes211and212. The penetration electrodes351and352extend from the main surface201to the rear surface202. In the present reference example, filler resins602are filled into the penetration electrodes351and352.

The rear surface electrode370is formed on the rear surface202. In the present reference example, the rear surface electrode370includes intermediate individual electrodes371and372, an end portion individual electrode374and an end portion common electrode375. The intermediate individual electrodes371and372, the end portion individual electrode374and the end portion common electrode375are arranged side by side along the x-direction. The intermediate individual electrodes371and372are interposed between the end portion individual electrode374and the end portion common electrode375. The intermediate individual electrode371overlaps with the through-hole211when viewed in the z-direction. The intermediate individual electrode371is connected to the penetration electrode351. The intermediate individual electrode372overlaps with the through-hole212when viewed in the z-direction. The intermediate individual electrode372is connected to the penetration electrode352. The end portion individual electrode374is arranged near one end of the rear surface202in the x-direction and connected to the corner groove wiring line342. The end portion common electrode375is arranged near the other end of the rear surface202in the x-direction and connected to the corner groove wiring line341.

In the present reference example, a plurality of insulating films601is formed on the rear surface202. The insulating films601are arranged to cover the portion of the rear surface202exposed from the rear surface electrode370and some portions of the intermediate individual electrodes371and372. The wiring line300is not formed on the bottom surface203. Thus the entire bottom surface203may be exposed. When mounting the LED module101to the mounting substrate801shown inFIG. 23, a solder fillet802is formed which makes contact with the pad (not shown) of the mounting substrate801and the intermediate individual electrodes371and372. The end portion individual electrode374and the end portion common electrode375are arranged such that a portion of the solder fillet802fills a space surrounded by the end portion individual electrode374or the end portion common electrode375and the mounting substrate801.

The LED chips401,402and403are light sources of the LED module101. Each of the LED chips401,402and403has a structure in which a p-type semiconductor layer, an n-type semiconductor layer and an active layer interposed between the p-type semiconductor layer and the n-type semiconductor layer are laminated one above another. The LED chip401is die-bonded to the die bonding pad301and configured to emit, e.g., blue light. The LED chip402is die-bonded to the die bonding pad302and configured to emit, e.g., red light. The LED chip403is die-bonded to the die bonding pad303and configured to emit, e.g., green light. The LED chips401and402are connected to the branch wiring line323by wires500. The LED chip403is connected to the main surface junction wiring line322by a wire500. The distances between the LED chips401,402and403may range from 100 μm to 150 μm.

The intermediate individual electrode371is electrically connected to the LED chip401through the penetration electrode351. The intermediate individual electrode372is electrically connected to the LED chip402through the penetration electrode352. The end individual electrode374is electrically connected to the LED chip403through the corner groove wiring line342. The end common electrode375is electrically connected to the LED chips401,402and403through the corner groove wiring line341.

The transparent resin portion700is formed on the main surface201of the substrate200to cover the LED chips401,402and403. The transparent resin portion700is made of a transparent resin, e.g., an epoxy resin, or a resin that can transmit the light emitted from the LED chips401,402and403. In the present reference example, the transparent resin portion700has a trapezoidal shape when viewed in the y-direction and a rectangular shape when viewed in the x-direction. The transparent resin portion700has a z-direction dimension of, e.g., about 0.8 mm.

Next, description will be made on the operations of the LED module101.

With the present reference example, the paths extending from the intermediate individual electrodes371and372through the penetration electrodes351and352are used as electric power supply paths to the LED chips401and402. These paths do not have portions extending from the main surface201or the rear surface202to the bottom surface203. Accordingly, the space on the main surface201and the rear surface202necessary to form the wiring line300can be reduced and thus the size of the LED module101can be reduced.

The paths extending from the end portion individual electrode374and the end portion common electrode375through the corner groove wiring lines341and342are used as electric power supply paths to the LED chips401,402and403. With this configuration, the bottom surface203is not covered with the wiring line300at all. In other words, portions through which the wiring line300extends from the main surface201or the rear surface202to the bottom surface203need not be provided. Accordingly, the space on the main surface201and the rear surface202necessary to form the wiring line300can be further reduced.

As shown inFIG. 22, the through-holes211and212are formed at the side spaced apart from the bottom surface203in the y-direction. Therefore, even if the intermediate individual electrodes371and372are unintentionally deformed due to the existence of the through-holes211and212, the mounting posture of the LED module101shown inFIG. 23can be prevented from being disturbed by the deformation.

InFIGS. 24 to 31, components identical with or similar to those of the above-described reference example will be designated by like reference symbols.

FIGS. 24 to 27show an LED module according to a second reference example of the present disclosure. The LED module102of the present reference example includes three through-holes211,212and213, three individual electrodes371,372and373and two end portion common electrodes375and376. The LED module102further includes a reflector710. The LED module102has an x-direction dimension of about 2.0 mm, a y-direction dimension of about 0.5 mm and a z-direction dimension of about 0.9 mm. InFIG. 24, the transparent resin portion700is omitted for the sake of understanding.

The three through-holes211,212and213are formed in the substrate200. Penetration electrodes351,352and353(the penetration electrodes351and353are not shown) are formed on the inner surfaces of the through-holes211,212and213, respectively. The individual electrodes371,372and373are connected to the penetration electrodes351,352and353, respectively. Three die bonding pads301,302and303are formed on the main surface201. Three LED chips401,402and403are die-bonded to the die bonding pads301,302and303, respectively, and electrically connected to the penetration electrodes351,352and353, respectively. The through-holes211and213(the penetration electrodes351and353) are respectively arranged at the upper side of the LED chips401and403inFIG. 24. The through-hole212(the penetration electrode352) is arranged at the lower side of the LED chip402inFIG. 24.

Two bonding pads311and312are formed on the main surface201. The bonding pad311and the LED chip401are connected by a wire500. The bonding pad312and the LED chips402and403are connected by wires500. The bonding pad311is connected to one of the quarter-circular arc portions321and electrically connected to the end portion common electrode375through the corner groove wiring line341. The bonding pad312is connected to the other quarter-circular arc portion321and electrically connected to the end portion common electrode376through the corner groove wiring line342.

The reflector710is made of, e.g., a white resin, and formed on the main surface201. The reflector710includes a reflecting surface711. The reflecting surface711surrounds the LED chips401,402and403and serves to reflect the light emitted from the LED chips401,402and403in the x-direction or y-direction toward the z-direction. The reflector710may have a z-direction dimension of, e.g., about 0.4 mm. The region surrounded by the reflector710is filled with the transparent resin portion700.

With the present reference example, the size of the LED module102can be reduced. In particular, by arranging the LED chips401,402and403and the through-holes211,212and213in a so-called zigzag pattern, the x-direction dimension of the substrate200can be reduced.

FIGS. 28 to 31show an LED module according to a third embodiment of the present disclosure. The LED module103of the present embodiment differs from the above-described LED module102in terms of the configuration of the wiring line300on the main surface201and the rear surface202. The LED module103has an x-direction dimension of about 2.7 mm, a y-direction dimension of about 0.5 mm and a z-direction dimension of about 0.9 mm. InFIG. 28, the transparent resin portion700is omitted for the sake of understanding. InFIG. 31, the region where the insulating film601is formed is hatched.

In the present embodiment, the die bonding pad303is connected to the quarter-circular arc portions321. The quarter circular arc portions321are connected to the corner groove wiring line342. The rear surface electrode370includes an end portion individual electrode374. The end portion individual electrode374is connected to the corner groove wiring line342. The bonding pad312connected to the LED chip403by the wire500is connected to the penetration electrode353(not shown) formed in the through-hole213. The rear surface electrode370includes a rear surface junction wiring line378. The rear surface junction wiring line378interconnects the penetration electrode353and the end portion common electrode375. On the main surface201, the bonding pad311and the LED chips401and402are connected by the wires500. The bonding pad311is electrically connected to the end portion common electrode375through the corner groove wiring line341. Thus the end portion common electrode375is electrically connected not only to the LED chips401and402but also to the LED chip403. The through-holes211and212overlap with the LED chips401and402when viewed in the z-direction.

The wire500interconnecting the LED chip402and the bonding pad311has a portion overlapping with the LED chip401when viewed in the z-direction. The center of the LED chip401is misaligned with the center of the LED chip402in the y-direction. When viewed in the z-direction, the through-hole212includes a portion overlapping with the LED chip402and a portion protruding from the LED chip402.

The insulating film601is arranged to cover the rear surface electrode370. More specifically, the insulating film601covers the rear surface junction wiring line378. The insulating film601at least partially exposes the individual electrodes371and372. The insulating film601covers the portions of the individual electrodes371and372adjoining the rear surface junction wiring line378. Accordingly, the insulating film601can be prevented from being rolled up. The insulating film601exposes both the end portion individual electrode374and the end portion common electrode375.

With the present embodiment, the size of the LED module103can be reduced. In particular, by allowing the through-holes211and212to overlap with the LED chips401and402when viewed in the z-direction, the size of the substrate200, i.e., the size of the LED module103, can be further reduced.

In the LED module103, the wire500interconnecting the LED chip402and the bonding pad311has a portion overlapping with the LED chip401when viewed in the z-direction. With this configuration, the wire500can be bonded to the LED chip402and the bonding pad311which are arranged at opposite sides of the LED chip401. That is to say, no bonding pad for bonding the wire500connected to the LED chip402needs to be provided between the LED chip402and the LED chip401or between the LED chip402and the LED chip403. Accordingly, the distance between the LED chip402and the LED chip401or the distance between the LED chip402and the LED chip403can be reduced.

In the LED module103, the center of the LED chip401is misaligned with the center of the LED chip402in the y-direction. This helps prevent the wire500connected to the LED chip401and the wire500connected to the LED chip402from making contact with each other. In addition, this helps prevent a capillary tube used when forming one of the wires500from making contact with another of the wires500.

In the LED module103, the through-hole212includes, when viewed in the z-direction, a portion overlapping with the LED chip402and a portion protruding from the LED chip402. With this configuration, the distance between the individual electrode372overlapping with the through-hole212and the rear surface junction wiring line378can be secured.

In the LED module103, the insulating film601is arranged to cover the rear surface junction wiring line378. With this configuration, the solder making contact with the individual electrodes371and372can be prevented from adhering to the rear surface junction wiring line378. Accordingly, a problem in that the individual electrodes371and372are short-circuited to the rear surface junction wiring line378through the solder can be prevented.