JP4780939B2 - Light emitting device - Google Patents

Description

The present invention relates to a light emitting device including a light emitting element such as a light emitting diode.

In recent years, with the increase in brightness and whiteness of light-emitting devices using light-emitting elements, light-emitting devices have been frequently used for backlights of mobile phones, large liquid crystal TVs, and the like. However, as the brightness of light emitting elements increases, the heat generated from the light emitting device also increases, and in order to eliminate the decrease in the brightness of the light emitting elements, such heat dissipation that dissipates such heat more quickly than the elements is high. A wiring board for a light emitting element having the above is required (see Patent Documents 1 and 2).
JP 10-215001 A JP 2003-347600 A

  However, the alumina material conventionally used for the insulating substrate of the wiring board has a low thermal conductivity of about 15 W / m · K, so aluminum nitride having a high thermal conductivity has begun to attract attention as an alternative. However, aluminum nitride has a high raw material cost and a high process cost due to high-temperature firing due to difficult sintering. In addition, since the coefficient of thermal expansion is as small as 4-5x10-6 / ° C, it is connected due to the difference in thermal expansion when mounted on a general-purpose printed circuit board with a coefficient of thermal expansion of 9x10-6 / ° C or higher. There was a problem that reliability was impaired.

  On the other hand, when a resin-based wiring board is used, the thermal expansion coefficient approaches that of the printed circuit board, so there is no problem of mounting reliability between the resin-based wiring board and the printed circuit board. The thermal conductivity is as low as 0.05 W / m · K, and the problem with heat cannot be dealt with at all. That is, a light-emitting element wiring board that is inexpensive, excellent in heat conduction, and excellent in mounting reliability has not yet been provided.

Accordingly, the present invention is inexpensive, and to provide an excellent light emission device heat dissipation and mounting reliability.

The light emitting device of the present invention, light emission provided on one major surface of the flat plate-like insulating substrate and the insulating substrate surface or the conductive layer formed on at least one of the inner and front Symbol insulating substrate made of a low-temperature co-fired ceramic a light emitting element wiring board that having a a mounting portion for mounting the device, it comprises a and a light emitting element mounted on the mounting portion of the wiring board for the light emitting element, the insulating directly below the mounting portion A lump that is provided penetrating the base, has at least one of Cu, Ag, and Au as a main component, has a higher thermal conductivity than the insulating base, and has a cross-sectional area that is greater than the mounting area of the light emitting element. A penetrating metal body is fired simultaneously with the insulating base, and a boundary between the insulating base and the penetrating metal body formed on the main surface of the light-emitting element wiring substrate is a coating layer mainly composed of metal. to be covered by And butterflies.

In the light emitting device of the present invention, it is preferable that the through metal body is a composite of at least a metal material and a ceramic material.

In the light emitting device of the present invention, it is preferable that the through metal body forms at least a part of an electric circuit.

In the light emitting device of the present invention, it is desirable that at least one end face of the through metal body is covered with an insulating film.

In the light emitting device of the present invention, it is desirable that the thermal expansion coefficient of the insulating base at 40 to 400 ° C. is 9 to 18 × 10 ⁻⁶ / ° C.

In the light emitting device of the present invention, it is desirable that the conductor layer or the penetrating metal body is mainly composed of at least one of Cu, Ag, and Au.

In the light emitting device of the present invention, it is desirable that a frame for accommodating the light emitting elements is formed on the main surface on the side where the mounting portion of the wiring board for light emitting elements is formed.

According to the light emitting device of the present invention, heat dissipation is excellent, heat generation itself can be reduced, and characteristics such as a thermal expansion coefficient of the insulating base can be arbitrarily changed. The thermal expansion mismatch can be suppressed, which can contribute to improving the bonding reliability of the light emitting device. Further, since the insulating substrate contains a relatively large amount of glass, the reflectance of light is high and the utilization factor of light can be increased.

As shown in FIG. 1A, for example, a wiring board for a light-emitting element that constitutes a light- emitting device of the present invention includes an insulating base 1 made of low-temperature fired ceramic fired at 1050 ° C. or lower, and the main surface of the insulating base 1 Insulating so that the connection terminal 3 with the light emitting element formed on 1a, the external electrode terminal 5 formed on the other main surface 1b of the insulating base 1, and the connection terminal 3 and the external electrode terminal 5 are electrically connected. The through conductor 7 is provided through the base body 1.

  A mounting portion 9 for mounting a light emitting element is formed between one connection terminal 3a and the other connection terminal 3b. Further, a penetrating metal body 10 is formed immediately below the mounting portion 9 so as to penetrate the insulating base 1.

Further, for example, the wiring board 11 for emitting light device, as shown in FIG. 1 (b), the mounting portion 9 side, the frame body 13 for accommodating a light emitting element mounted is formed.

  According to the present invention, in such a light emitting element wiring substrate 11, it is important to form the insulating substrate 1 from low-temperature fired ceramics fired at 1050 ° C. or lower. As a result, it is possible to simultaneously sinter with a metal such as copper, silver or gold having low resistance and high thermal conductivity, and the wiring substrate 11 for a light emitting element having a low resistance wiring layer can be easily and inexpensively formed. can do. In addition, since low-temperature fired ceramics generally contain a large amount of glass components, the heat conductivity is low and heat dissipation is required as compared with, for example, alumina and aluminum nitride that are fired at a temperature exceeding 1050 ° C. Although it has not been used as a member, it has a thermal conductivity several times higher than that of an organic member. In addition, it has a low resistance of about 1/3 compared to a wiring layer mainly composed of tungsten or the like used for alumina or aluminum nitride. In addition, since the low-temperature fired ceramic generally has many components derived from glass, a smooth surface state can be easily formed, and light emitted from the light-emitting element can be efficiently reflected. In addition to the reflectance, it is easy to control transparency and color tone, and it is suitable for various light emitting devices.

These effects described above are synergistically suppressed, heat generation due to the wiring layers 3, 5, and 7 can be suppressed, and heat can be released to the outside of the device relatively quickly, and light emitted from the light emitting device. Can be used efficiently.

  It is also important to form the penetrating metal body 10 having a higher thermal conductivity than the insulating substrate 1 through the insulating substrate 1. Accordingly, the heat conduction of the light emitting element wiring substrate 11 can be remarkably improved, and further, heat generated from the light emitting element can be quickly radiated to the outside of the light emitting element wiring substrate 11, and the light emission. It becomes possible to prevent a decrease in luminance of the element. The penetrating metal body 10 is in a lump shape.

  Then, it is preferable that the through metal body 10 has a cross-sectional area larger than the mounting area of the light emitting element mounted on the light emitting element wiring substrate 11, in particular, larger than the mounting area. By increasing the cross-sectional area, the heat radiating portion is increased and heat generated from the light emitting element can be quickly dissipated. In particular, the cross-sectional area is preferably 1.1 times, and more preferably 1.2 times.

Furthermore, it is preferable that the through metal body 10 be co-fired as a composite of at least a metal material and a ceramic material. By using a composite, it becomes easy to control the thermal expansion coefficient. For example, the thermal expansion coefficient between the through metal body 10 and the insulating base 1 can be made close. Thermal expansion mismatch can be prevented. In particular, the difference in thermal expansion coefficient between the insulating substrate 1 and the through metal body 10 is preferably 4.0 × 10 ⁻⁶ / ° C. or less, more preferably 2.0 × 10 ⁻⁶ / ° C. or less, and most preferably. Is desirably 1.0 × 10 ⁻⁶ / ° C. or less.

  Further, the ceramic material added by simultaneous firing can increase the adhesive strength with the insulating substrate 1.

  And it is preferable to provide the penetrating metal body 10 with a function as an electric circuit. A conduction terminal is not required, and the light emitting element wiring substrate 11 can be downsized.

  Further, by covering at least one end face of the through metal body 10 with the insulating film 6, a short circuit with the external terminal can be prevented, and when the light emitting device is mounted on a printed board or the like, the wiring is directly under the through metal body 10 Contributes to miniaturization of equipment.

  Further, by forming the insulating film so as to cover the end surface of the penetrating metal body 10 on the light emitting element mounting side, a short circuit between the light emitting element electrodes can be prevented, and the flip chip mounting of the light emitting element can be simplified.

Moreover, it is preferable that the thermal expansion coefficient in 40-400 degreeC of the insulating base | substrate 1 is 9-18 * 10 < ^-6 > / degreeC. As a result, the mounting reliability of a general-purpose product having a thermal expansion coefficient of 9 × 10 ⁻⁶ / ° C. or more on a printed circuit board can be improved, and the through metal body 10 having a thermal expansion coefficient of 9 × 10 ⁻⁶ / ° C. or more. Adhesion reliability can be improved. In particular, the coefficient of thermal expansion is preferably 10 to 17 × 10 ⁻⁶ / ° C., and more preferably 12 to 16 × 10 ⁻⁶ / ° C.

  Further, it is desirable to use a low-temperature fired ceramic that exhibits high strength.

  As the insulating substrate 1 that exhibits such characteristics, for example, low-temperature fired ceramics described in JP-A Nos. 2002-167265 and 2003-73163 are suitably used as low-temperature fired ceramics.

According to Japanese Patent Laid-Open No. 2002-167265, it is important to contain a quartz crystal in the composition in a proportion of 30 to 60% by mass, particularly 35 to 55% by mass. The coefficient can be increased.

  In order to produce the insulating substrate 1, an organic resin binder having an appropriate shape is added to the glass ceramic composition, and then a sheet shape is formed by a desired forming means such as a doctor blade, a rolling method, a die press, or the like. After forming into an arbitrary shape, the organic resin binder component blended for molding is removed by heat treatment in an air atmosphere at around 700 ° C. From the viewpoint of efficiently removing the organic resin binder component, the shrinkage start temperature of the molded body is desirably about 700 to 850 ° C.

  Firing is performed in a non-oxidizing atmosphere at 850 ° C. to 1050 ° C. when co-firing with a metal that is easily oxidized, such as copper, thereby densifying the material to a relative density of 95% or more. If the firing temperature at this time is lower than 850 ° C., it cannot be densified, and if it exceeds 1050 ° C., the metallized layer is melted by simultaneous firing with the metallized wiring layer.

  Needless to say, when a metal such as silver that is difficult to oxidize is used as the wiring layer, it may be fired in the air.

  In order to manufacture the light emitting element wiring substrate 11 in which the metallized wiring layer 3 made of Cu is disposed on the surface of the insulating base 1 made of the glass ceramic, the glass as described above for forming the insulating base 1 is used. Add a suitable organic binder, plasticizer and solvent to the raw material powder made of ceramic material to make a slurry, and then apply the doctor blade method or calendar roll method to produce a green sheet (raw sheet). Make it.

  Then, for the metallized wiring layer 3 and the external electrode terminal 5, a Cu powder coated with a metal oxide on the surface, an organic binder, a plasticizer, and a solvent are added and mixed to prepare a metallized paste. The coating layer can be formed on the surface of the Cu powder by a plating method, a sputtering method, or the like.

  Then, this metallized paste is printed on a green sheet in a predetermined pattern by a well-known screen printing method. In some cases, the green sheet is appropriately punched to form a through hole, and this hole is also filled with a metallized paste that becomes the through conductor 7. A plurality of these green sheets are laminated.

  Thereafter, the laminate is heat-treated in a nitrogen atmosphere containing water vapor at 500 to 700 ° C. to remove the organic resin binder, and then fired in a non-oxidizing atmosphere such as nitrogen at 850 ° C. to 1050 ° C. for insulation. Baking until the substrate 1 is densified to a relative density of 95% or more.

  Thereafter, a plating layer of Cu, Ag, Au, Ni, or the like is formed on the surface of the metallized wiring layer 3 on the surface of the wiring substrate 11 for the light emitting element by an electrolytic plating method or an electroless plating method, whereby the light emitting element of the present invention. The wiring board 11 can be completed.

A wiring circuit is formed on the wiring board 11 for the light emitting element by forming the connection terminal 3, the external electrode terminal 5, the through conductor 7, and the through metal body 10 on the surface or inside of the insulating base 1. Can do. The through metal body 10 is made of a ceramic green sheet, a metal material, and a ceramic material. The through metal body 10 includes a step of producing a metal sheet having substantially the same thickness as the ceramic green sheet, and a through hole is formed at a predetermined position of the ceramic green sheet. A step of laminating a metal sheet on a ceramic green sheet in which a through hole is formed, and by pressing a through hole forming portion in the ceramic green sheet from the metal sheet side, a part of the metal sheet is embedded in the through hole, A ceramic green sheet and a metal sheet were integrated.

  Then, the conductor and the penetrating metal body used for these wiring circuits are formed by using at least one of Cu, Ag, and Au as a main component, and are fired simultaneously with the insulating base 1, thereby connecting terminals 3 and external electrode terminals. 5, the through conductor 7 and the through metal body 10 can be formed, and an inexpensive light emitting element wiring substrate 11 can be obtained.

  In addition, the reflectance can be improved by applying Al or Ag plating to the surfaces of the connection terminal 3 and the through metal body 10.

  Further, the boundary between the insulating base 1 and the penetrating metal body 10 formed on the main surface of the light emitting element wiring substrate 11 is covered with a coating layer mainly composed of at least one of metal, ceramic, and resin. Is desirable. By covering between the metal body and the insulating substrate with these coating layers, the difference in thermal expansion can be buffered, and the occurrence of cracks at the boundary between the insulating substrate 1 and the penetrating metal body 10 can be suppressed.

  Further, it is preferable to provide a frame 13 for housing the light emitting element on the main surface of the mounting portion 9 of the wiring board 11 for the light emitting element. As a result, the light emitting element can be protected, and a phosphor or the like can be easily arranged around the light emitting element 21, and the light emitted from the light emitting element can be reflected by the frame and guided in a predetermined direction. is there.

  Moreover, since the frame 13 is formed of ceramics, the insulating substrate 1 and the frame 13 can be fired at the same time, and the process is simplified. Therefore, the inexpensive light-emitting element wiring substrate 11 is easily manufactured. can do. In addition, since ceramics are excellent in heat resistance and moisture resistance, the light emitting element wiring substrate 11 has excellent durability even when used for a long period of time or under adverse conditions.

  In addition, by forming the frame body 13 from a metal that is inexpensive and excellent in workability, even the frame body 13 having a complicated shape can be easily manufactured at low cost, and an inexpensive wiring board for a light-emitting element. 11 can be supplied. This metal frame 13 can be suitably formed by Al, Fe-Ni-Co alloy, etc., for example. Further, a plating layer (not shown) made of Ni, Au, Ag or the like may be formed on the surface of the frame 13.

  In addition, when forming the frame 13 with a metal in this way, the metal layer 17 and the frame 13 can be joined via an adhesive made of, for example, an epoxy resin.

  Then, for example, as shown in FIG. 2A, an LED chip 21 or the like is mounted on the light emitting element wiring substrate 1 of the present invention described above as a light emitting element 21, and power is supplied to the light emitting element 21 through the bonding wire 23. Thus, the light emitting element 21 can be made to function, and the heat generated from the light emitting element 21 can be quickly released from the through metal body 10, so that a heat radiating member such as a heat sink is not necessary, and the mounted electric apparatus is small. By making the thermal expansion coefficient close to that of the printed circuit board, it is possible to suppress mismatch of the thermal expansion coefficient with the printed circuit board and the molding material, and thus the light emitting device 25 with high bonding reliability can be obtained. In addition, by providing a heat sink, it is needless to say that heat dissipation is further improved, and for example, provision of a cooling device such as a heat sink is not excluded.

Further, an LED chip 21 or the like is mounted on the mounting portion 9 formed on the light emitting element wiring substrate 11 as, for example, the light emitting element 21, and the LED chip 21 and the connection terminal 3 are electrically connected by the bonding wire 23. By supplying power, the light emitted from the light emitting element 21 can be reflected by the insulating base 1 and the frame 13 and guided in a predetermined direction, so that the highly efficient light emitting device 25 is obtained. Further, since the thermal conductivity of the insulating base 1 and the frame 13 is high, heat generated from the light emitting element 21 can be quickly released, and a reduction in luminance due to heat generation can be suppressed.

  In addition, as shown in FIG. 2B, in the light emitting device 25 in which the frame body 13 is mounted on the main surface 1 a of the light emitting element wiring substrate 1 on the side where the light emitting element 21 is mounted, light is emitted inside the frame body 13. By storing the element 21, the light emitting element 21 can be easily protected.

  In the example shown in FIGS. 2A and 2B, the light emitting element 21 is fixed to the light emitting element wiring substrate 1 with an adhesive 29, and power is supplied by the wire bond 23. Needless to say, the connection form with the element wiring board 1 may be flip-chip connection.

  Moreover, although the light emitting element 21 is covered with the molding material 31, it may be sealed using a lid (not shown) without using the molding material 31, or the molding material 31 and the lid. And may be used in combination. In the case where the lid is used, and the light emitting element 21 is used, it is desirable that the lid is made of a translucent material such as glass.

  In addition, when mounting the light emitting element 21, you may add the fluorescent substance (not shown) for wavelength-converting the light which the light emitting element 21 radiates | emits to this molding material 31 as needed.

  Needless to say, the insulating substrate 1 may be laminated in multiple layers.

As a raw material powder for a wiring board for a light-emitting element, a quartz powder having a purity of 99% or more and an average particle size of 5 μm is 30% by mass, a purity of 99% or more and an average grain size of 3 μm is SiO ₂ 29% by mass—BaO 64% by mass—B ₂ O ₃ 3% -Al ₂ O ₃ 3% by mass-CaO 1% by mass of glass powder 70% by mass, and after adding an organic binder and mixing well, an organic resin for molding (binder) A slurry was prepared by mixing an acrylic binder and toluene as a solvent. Thereafter, a green sheet for an insulating substrate having composition 1 was produced by a doctor blade method.

Moreover, 60% by mass of a crystalline glass powder having a composition of purity 99% or more, SiO ₂ 50% by mass—Al ₂ O ₃ 5% by mass—MgO 20% by mass—CaO 25% by mass with an average grain size of 3 μm, inorganic As the filler, 40% by mass of alumina having a purity of 99% or more and an average particle diameter of 2 μm was mixed, and a ceramic green sheet having composition 2 was produced in the same manner as described above.

  On the other hand, Cu, Ag, Au powder having an average particle diameter of 5 μm and glass powder having an average particle diameter of 5 μm as a ceramic material were mixed as shown in Table 1 and kneaded with an acrylic binder to prepare a conductor paste.

  Then, the same metal and ceramic material as the conductor paste are mixed in the same ratio as the conductor paste, and further, an acrylic binder as a molding organic resin (binder) and toluene as a solvent are mixed to prepare a slurry. did. Thereafter, a metal sheet having substantially the same thickness as the ceramic green sheet was produced by a doctor blade method.

  The ceramic green sheet was punched to form a via hole having a diameter of 100 μm. The via hole was filled with a conductive paste by a screen printing method and printed and applied in a wiring pattern.

Then, a through hole is formed at a predetermined position of the ceramic green sheet, and a part of the metal sheet is embedded in the through hole by pressing a through hole forming portion of the ceramic green sheet from the metal sheet. The ceramic green sheet and the metal sheet And a metal sheet to be a through metal body was embedded in a ceramic green sheet.

  The thus produced metal sheet and ceramic green sheet comprising the conductor paste were combined, aligned, and laminated and pressure-bonded to produce a laminate having an outer shape of 10 mm × 10 mm × thickness of 0.6 mm. And after performing degreasing | defatting in nitrogen steam mixed atmosphere, it baked at the highest temperature of 900 degreeC continuously for 1 hour. Then, a connection terminal was formed on one main surface of the insulating base, an external electrode terminal was formed on the other main surface, and a light-emitting element wiring board in which both were connected by a through conductor was produced. Thereafter, Ni, Au and Ag plating were sequentially applied to the surfaces of the connection terminal and the external electrode terminal.

  For some samples, after firing, an epoxy resin was applied to the boundary between the insulating substrate 1 and the penetrating metal body 8 and cured under conditions of 150 ° C. for 1 hour, and a coating layer having a thickness of about 20 μm. Formed.

  Further, some of the wiring boards for light emitting elements have an outer dimension of 10 mm × 10 mm × 2 mm on the side where the mounting portion is formed, the inner diameter on the side in contact with the insulating base is 4 mm, and the inner diameter on the opposite side is 8 mm. A frame made of the same material as the insulating substrate having a tapered through hole or a metal frame was formed.

  The light-emitting element wiring board in which the frame body was formed of the same material as the insulating base body was manufactured by forming the insulating base body and the frame body as a single body with a green sheet and performing simultaneous firing.

Moreover, as a metal frame, an Al metal frame having a thermal expansion coefficient of 23 × 10 ⁻⁶ / ° C. and a thermal conductivity of 238 W / m · K, and a thermal expansion coefficient of 6 × 10 ⁻⁶ / ° C. A metal frame made of Fe—Ni—Co alloy having a thermal conductivity of 17 W / m · K was used.

  The light emitting element wiring board provided with the metal frame was manufactured by bonding the frame to the mounting portion side of the insulating base with glass.

An LED chip, which is a light emitting element with an output of 1.5 W, is mounted on the mounting part using an epoxy resin as an adhesive on these wiring boards for light emitting elements, and the LED chip and the connection terminal are connected by a bonding wire. The chip and the connection terminal were covered with a mold material made of an epoxy resin having a thermal expansion coefficient of 40 × 10 ⁻⁶ / ° C. to obtain a light emitting device.

  The obtained light-emitting device was subjected to a temperature cycle test of −55 ° C. to 125 ° C. up to 3000 cycles. After the test, the peeling state of the adhesion interface between the through metal body and the insulating substrate was confirmed.

  Further, a current of 0.4 A was applied to the light emitting device, and the total radiant flux was measured.

  Moreover, the thermal conductivity of the insulating substrate and the through metal body was measured by a laser flash method, and the thermal expansion coefficient was measured in the range of 25 to 400 ° C. by TMA.

  With the metal frame, Al and Fe-Ni-Co alloy were joined using an epoxy resin at 150 ° C for 1 hour.

Table 1 shows the characteristics and test results of the light-emitting element wiring substrate manufactured through the above steps.

  As shown in Table 1, sample no. 5 does not dissipate heat due to the penetrating metal body, and therefore cannot sufficiently dissipate heat from the LED chip generated when the light emitting device is energized, and although the characteristics are inferior to other samples, the wiring layer Because of the small heat generation due to the above and high reflectivity, it was sufficiently practical.

  On the other hand, sample No. In 1-4, 6-13, there was no excessive heating of the LED chip, and very high luminous efficiency could be realized.

  In particular, Sample No. with a frame was formed. In 1-4, 6-9, 12 and 13, the optical characteristics were further improved compared to the case where no frame was provided.

  Sample No. 1 to 13, it can be seen that there are no cracks between the penetrating metal body and the insulating substrate, and that there is excellent reliability. Sample No. Reference numerals 6 and 7 are reference samples.

(A) is a cross-sectional view of a wiring substrate emitting light element, (b) are cross-sectional views of a wiring substrate emitting light device having a frame body. (A) is sectional drawing of the light-emitting device of this invention, (b) is sectional drawing of the light-emitting device of this invention which provided the frame.

DESCRIPTION OF SYMBOLS 1 ... Insulation base | substrate 3 ... Connection terminal 5 ... External electrode terminal 7 ... Penetration conductor 10 ... Penetration metal body 11 ... Wiring board 13 for light emitting elements ... Frame body 13a ... -Inner wall surface 21 of the frame body ... Light emitting element 25 ... Light emitting device 31 ... Mold material

Claims (7)

A mounting portion for mounting a light emitting element provided on one main surface of the low temperature sintering made of a ceramic plate-shaped insulating substrate and the insulating substrate surface or at least one which is formed on the conductive layer and before Symbol insulating base of the internal a light emitting element wiring board that have a,
A light emitting element mounted on the mounting portion of the light emitting element wiring substrate,
The light-emitting element mounting area is provided directly below the mounting portion, penetrating the insulating base, has at least one of Cu, Ag, and Au as a main component and has a higher thermal conductivity than the insulating base. The massive penetrating metal body having the above cross-sectional area is fired simultaneously with the insulating base, and the boundary between the insulating base and the penetrating metal body formed on the main surface of the wiring board for light emitting element is A light-emitting device which is covered with a coating layer containing a metal as a main component . The light-emitting device according to claim 1, wherein the through metal body is a composite of at least a metal material and a ceramic material. The light-emitting device according to claim 1, wherein the through metal body forms at least a part of an electric circuit. The light-emitting device according to claim 1, wherein at least one end face of the through metal body is covered with an insulating film. 5. The light-emitting device according to claim 1, wherein the insulating base has a thermal expansion coefficient of 9 to 18 × 10 ⁻⁶ / ° C. at 40 to 400 ° C. 5. 6. The light emitting device according to claim 1, wherein the conductor layer contains at least one of Cu, Ag, and Au as a main component. The frame body for accommodating the said light emitting element is formed in the main surface at the side in which the mounting part of the said wiring board for light emitting elements was formed, The Claim 1 thru | or 6 characterized by the above-mentioned. Light-emitting device .

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