JP6460201B2 - Light emitting device - Google Patents

Description

  The present invention relates to a light emitting device.

  There is known a light emitting device in which a mounting surface of a support (base material) includes a recess, and the support (base material) and the mounting substrate are fixed by filling the recess with a brazing material (for example, a patent) Reference 1).

JP 2013-041865 A

  An object of this invention is to provide the light-emitting device which can improve the joint strength with a mounting board | substrate, suppressing the strength fall of a base material.

  The light-emitting device according to one embodiment of the present invention is adjacent to the front surface, the front surface extending in the first direction that is the longitudinal direction and the second direction that is the short direction, the back surface that is located on the opposite side of the front surface, A base material having a bottom surface orthogonal to the front surface and a top surface located on the opposite side of the bottom surface, a first wiring disposed on the front surface, a second wiring disposed on the back surface, and the first A substrate including a wiring and a via hole that electrically connects the second wiring; at least one light-emitting element that is electrically connected to the first wiring and placed on the first wiring; and the light emission A light-emitting device including a side surface of an element and a light-reflective coating member that covers a front surface of the substrate, wherein the base material is separated from the via hole in a front view, and is formed on the back surface and the bottom surface. A plurality of indentations, wherein the substrate has a plurality of indentations A third wiring that covers the inner wall of the depression and is electrically connected to the second wiring; and each of the depths of the plurality of depressions in the front direction from the back surface is lower than the upper surface side. Deep on the side.

  According to the light emitting device of the present invention, it is possible to provide a light emitting device capable of improving the bonding strength with the mounting substrate while suppressing the strength reduction of the base material.

1A is a schematic perspective view 1 of the light emitting device according to Embodiment 1. FIG. 1B is a schematic perspective view 2 of the light emitting device according to Embodiment 1. FIG. 1C is a schematic front view of the light emitting device according to Embodiment 1. FIG. 2A is a schematic end view taken along line 2A-2A in FIG. 1C. 2B is a schematic end view taken along line 2B-2B in FIG. 1C. 3A is a schematic bottom view of the light emitting device according to Embodiment 1. FIG. 3B is a schematic bottom view of the deformability of the light emitting device according to Embodiment 1. FIG. 3C is a schematic front view of the base material according to Embodiment 1. FIG. 4A is a schematic rear view of the light emitting device according to Embodiment 1. FIG. 4B is a schematic rear view illustrating a modification of the light emitting device according to Embodiment 1. FIG. 4C is a schematic rear view illustrating a modification of the light emitting device according to Embodiment 1. FIG. FIG. 4D is a schematic bottom view of deformability of the light-emitting device according to Embodiment 1. FIG. 4E is a schematic bottom view of deformability of the light-emitting device according to Embodiment 1. FIG. 4F is a schematic bottom view of deformability of the light-emitting device according to Embodiment 1. FIG. 5A is a schematic right side view of the light-emitting device according to Embodiment 1. FIG. FIG. 5B is a schematic left side view of the light emitting device according to the first embodiment. FIG. 6 is a schematic top view of the light emitting device according to the first embodiment. FIG. 7 is a schematic front view of the light emitting device according to the second embodiment. FIG. 8A is a schematic end view taken along line 8A-8A in FIG. 8B is a schematic end view taken along line 8B-8B of FIG. FIG. 9A is a schematic bottom view of the light emitting device according to the second embodiment. FIG. 9B is a schematic rear view of the light emitting device according to the second embodiment. FIG. 10 is a schematic front view of the light emitting device according to the third embodiment. 11 is a schematic end view taken along line 11A-11A in FIG. FIG. 12 is a schematic bottom view of the light emitting device according to the third embodiment. FIG. 13 is a schematic rear view of the light emitting device according to the third embodiment. FIG. 14 is a schematic right side view of the light emitting device according to the third embodiment. FIG. 15 is a schematic front view illustrating a modification of the light emitting device according to the third embodiment. 16 is a schematic end view taken along line 15A-15A in FIG. FIG. 17 is a schematic front view of the light emitting device according to the fourth embodiment. 18 is a schematic end view taken along line 18A-18A in FIG. FIG. 19 is a schematic bottom view of the light emitting device according to the fourth embodiment. FIG. 20 is a schematic rear view of the light emitting device according to the fourth embodiment. FIG. 21 is a schematic right side view of the light emitting device according to the fourth embodiment. FIG. 22 is a schematic rear view of the light emitting device according to the fifth embodiment. FIG. 23 is a schematic rear view of the light emitting device according to the sixth embodiment. FIG. 24 is a schematic rear view of the light emitting device according to the seventh embodiment. FIG. 25A is a schematic bottom view of a land pattern in which the light-emitting device according to Embodiment 1 is described with dotted lines. FIG. 25B is a schematic bottom view illustrating a modification of the land pattern in which the light-emitting device according to Embodiment 1 is described by dotted lines. FIG. 25C is a schematic bottom view illustrating a modification of the land pattern in which the light-emitting device according to Embodiment 1 is described by dotted lines. FIG. 26A is a schematic bottom view of a land pattern in which the light-emitting device according to Embodiment 4 is described with dotted lines. FIG. 26B is a schematic bottom view illustrating a modification of the land pattern in which the light-emitting device according to Embodiment 4 is described by dotted lines. FIG. 27 is a schematic front view of the light emitting device according to the eighth embodiment. 28A is a schematic end view taken along line 28A-28A in FIG. 28B is a schematic end view taken along line 28B-28B of FIG. FIG. 29 is a schematic bottom view of the light emitting device according to the eighth embodiment. FIG. 30 is a schematic rear view of the light emitting device according to the eighth embodiment. FIG. 31 is a schematic end view of a modification of the light emitting device according to the eighth embodiment.

  Embodiments of the invention will be described below with reference to the drawings as appropriate. However, the light-emitting device described below is for embodying the technical idea of the present invention, and the present invention is not limited to the following unless otherwise specified. In addition, the size, positional relationship, and the like of members illustrated in the drawings may be exaggerated for clarity of explanation.

<Embodiment 1>
A light emitting device 1000 according to an embodiment of the present invention will be described with reference to FIGS. 1A to 6. The light emitting device 1000 includes a substrate 10, at least one light emitting element 20, and a covering member 40. The substrate 10 includes a base material 11, a first wiring 12, a second wiring 13, a third wiring 14, and a via hole 15. The base material 11 includes a front surface 111 extending in a first direction that is a longitudinal direction and a second direction that is a short direction, a back surface 112 positioned on the opposite side of the front surface, and a bottom surface that is adjacent to the front surface 111 and orthogonal to the front surface 111. 113 and a top surface 114 located on the opposite side of the bottom surface 113. The substrate 11 further has a plurality of depressions 16. The first wiring 12 is disposed on the front surface 111 of the base material 11. The second wiring 13 is disposed on the back surface 112 of the base material 11. The via hole 15 electrically connects the first wiring 12 and the second wiring 13. The light emitting element 20 is electrically connected to the first wiring 12 and placed on the first wiring 12. The covering member 40 has light reflectivity and covers the side surface 202 of the light emitting element 20 and the front surface 111 of the substrate. The plurality of depressions 16 are separated from the via holes 15 in front view and open to the back surface 112 and the bottom surface 113. The third wiring 14 covers the inner walls of the plurality of depressions 16 and is electrically connected to the second wiring 13. Each of the depths of the plurality of depressions 16 in the direction from the back surface 112 to the front surface 111 has a depth W1 of the depression on the bottom surface side deeper than the depth W2 of the depression on the upper surface side. In this specification, orthogonal means 90 ± 3 °.

  The light emitting device 1000 can be fixed to the mounting substrate by a joining member such as solder formed in the plurality of depressions 16. Since the bonding member can be positioned in the plurality of depressions, the bonding strength between the light emitting device 1000 and the mounting substrate can be improved as compared with the case of one depression. As shown in FIG. 2A, the depths of the plurality of depressions in the front direction (Z direction) from the back are deeper on the bottom side than the top side, so that the upper surface side of the depressions in the front direction (Z direction) from the back side. It is possible to make the thickness W5 of the base material located at the thickness larger than the thickness W6 of the base material located on the bottom side of the recess. Thereby, the strength reduction of a base material can be suppressed. Moreover, since the depth W1 of the dent on the bottom side increases, the volume of the bonding member formed in the dent increases, so that the bonding strength between the light emitting device 1000 and the mounting substrate can be improved. Even if the light emitting device 1000 is a top emission type (top view type) in which the back surface 112 of the base material 11 and the mounting substrate are mounted to face each other, the bottom surface 113 of the base material 11 and the mounting substrate are mounted to face each other. Even in the side light emission type (side view type), the bonding strength with the mounting substrate can be improved by increasing the volume of the bonding member. In the present specification, the front direction from the back is also referred to as the Z direction.

  The bonding strength between the light emitting device 1000 and the mounting substrate can be improved particularly in the case of the side light emitting type. Since the depth of the recess in the Z direction is deeper on the bottom surface side than the upper surface side, the area of the opening of the recess on the bottom surface can be increased. By increasing the area of the opening of the depression on the bottom surface facing the mounting substrate, the area of the bonding member located on the bottom surface can also be increased. Thereby, since the area of the bonding member positioned on the surface facing the mounting substrate can be increased, the bonding strength between the light emitting device 1000 and the mounting substrate can be improved.

  As shown in FIG. 2A, the depth W1 of the recess 16 in the Z direction is shallower than the thickness W3 of the base material in the Z direction. That is, the depression 16 does not penetrate the substrate. When a hole penetrating the substrate is formed, the strength of the substrate is lowered. For this reason, the strength reduction of a base material can be suppressed by providing the hollow which does not penetrate a base material. The maximum depth of each of the plurality of depressions in the Z direction is preferably 0.4 to 0.8 times the thickness of the base material. When the depth of the recess is deeper than 0.4 times the thickness of the base material, the volume of the bonding member formed in the recess is increased, so that the bonding strength between the light emitting device and the mounting substrate can be improved. When the depth of the dent is shallower than 0.8 times the thickness of the base material, it is possible to suppress the strength reduction of the base material.

  In a cross-sectional view, the recess 16 preferably includes a parallel portion 161 extending from the back surface 112 in a direction parallel to the bottom surface 113 (Z direction). By providing the parallel part 161, even if the area of the opening part of the dent on the back surface is the same, the volume of the dent can be increased. By increasing the volume of the recess, the amount of bonding members such as solder that can be formed in the recess can be increased, so that the bonding strength between the light emitting device 1000 and the mounting substrate can be improved. In the present specification, “parallel” means that an inclination of about ± 3 ° is allowed. In addition, the recess 16 includes an inclined portion 162 that is inclined from the bottom surface 113 in a direction in which the thickness of the base material 11 is increased in a cross-sectional view. The inclined portion 162 may be straight or curved. Since the inclined portion 162 is a straight line, formation is facilitated by a drill having a sharp tip. In addition, the straight line in the inclined part 162 means that fluctuations such as bending and deviation of about 3 μm are allowed.

  As shown in FIG. 3A, it is preferable that the center depth W1 of each of the plurality of depressions 16 is the maximum of the depression depth in the Z direction on the bottom surface. By doing in this way, in the bottom face, the base material thickness W8 in the Z direction can be increased at the end of the recess in the X direction, so that the strength of the base material can be improved. In the present specification, the center means that a fluctuation of about 5 μm is allowed. As shown in FIG. 3B, which is a modification of the first embodiment, the depth W7 of the recess 16 in the Z direction may be substantially constant on the bottom surface. In other words, the deepest portion of the recess 16 may be a flat surface. The depression 16 can be formed by a known method such as a drill or a laser. On the bottom surface, the recess having the maximum central depth can be easily formed by a drill having a sharp tip. Moreover, by using a drill, the deepest part is a substantially cone shape, and the hollow which has a substantially cylindrical shape continuous from the circular shape of the bottom face of a substantially cone shape can be formed. By cutting a part of the dent by dicing or the like, the deepest part has a substantially semi-cylindrical shape, and a dent having a substantially semi-cylindrical shape continuing from a substantially semi-circular shape can be formed.

  As shown to FIG. 4A, it is preferable that each shape of the some hollow 16 is the same in a back surface. Since the shape of each of the plurality of dents is the same, the formation of the dent becomes easier than when the shapes of the dents are different from each other. For example, in the case where the dent is formed by a drilling method, the dent can be formed by one drill if the shapes of the plurality of dents are the same. Incidentally, the same in this specification means that a difference of about 5 μm is allowed.

  Moreover, the area of the opening part of several hollows in back view may be the same, and may differ. For example, as shown in FIG. 4B, the area of the opening of the recess 16C located in the center of the base material in the rear view is the same as that of each of the openings of the recess 16L located on the X + side and the recess 16R located on the X− side. It may be larger than the area. 4B, 4C, and the like, the right side on the X axis from the center of the light emitting device is the X + side, and the left side is the X− side. By increasing the area of the opening of the recess 16C located in the center of the base material, the bonding strength between the light emitting device and the mounting substrate can be improved. In addition, since the area of the opening of the recess 16L located on the X + side and the recess 16R located on the X− side is small, the area of the second wiring 13 can be easily increased. Since the area of the second wiring 13 is large, the inspection becomes easy when the probe needle is brought into contact with the second wiring in the characteristic inspection of the light emitting device. Further, as shown in FIG. 4C, the area of the opening of each of the depressions 16L located on the X + side and the depression 16R located on the X− side in the rear view is the area of the opening of the depression 16C located at the center of the substrate. May be larger. By increasing the area of each opening of the recess 16L located on the X + side and the recess 16R located on the X− side, the bonding strength between the light emitting device and the mounting substrate can be improved. Moreover, it is preferable that the area of the opening part of the dent 16L located in the X + side and the dent 16R located in the X− side in the rear view is substantially the same. By doing in this way, it becomes easy to suppress the bias | inclination of the joining member formed in the hollow 16L located in the X + side, and the joining member formed in the hollow 16R located in the X- side. Thereby, it becomes easy to suppress that the light emitting device is inclined and mounted on the mounting substrate.

  As shown in FIGS. 3A and 3B, the depths W1 and W7 of the plurality of depressions in the Z direction may be the same, or the depths of the plurality of depressions in the Z direction may be different as shown in FIG. 4D. Good. For example, as shown in FIG. 4D, the depth W1C in the Z direction of the depression 16C located in the center of the base material in the bottom view is located on the depth W1L and the X− side in the Z direction of the depression 16L located on the X + side. It may be deeper than the depth W1R in the Z direction of the recess 16R. 4D, 4E, and 4F, the left side on the X axis from the center of the light emitting device is the X + side, and the right side is the X− side. Since the depth W1C of the recess 16C located at the center of the base material is deep, the bonding strength between the light emitting device and the mounting substrate can be improved. The depth W1L in the Z direction of the depression 16L located on the X + side and the depth W1R in the Z direction of the depression 16R located on the X− side in the bottom view are deeper than the depression W1C of the depression 16C located in the center of the substrate. May be. Moreover, it is preferable that the depth W1L in the Z direction of the recess 16L located on the X + side and the depth W1R in the Z direction of the recess 16R located on the X− side are substantially the same. By doing in this way, since it becomes easy to suppress the bias | inclination with the joining member formed in the hollow located in the X + side, and the joining member formed in the hollow located in the X- side, a light-emitting device is mounted on a mounting board. It becomes easy to suppress mounting with inclination.

  As shown in FIG. 4D, the width D1C in the X direction of the depression 16C located in the center of the base material in the bottom view, the width D1L in the X direction of the depression 16L located on the X + side, and the X of the depression 16R located on the X− side. The width D1R in the direction may be substantially the same, and as shown in FIGS. 4E and 4F, the width D1C in the X direction of the depression 16C located in the center of the base material in the bottom view, the X direction of the depression 16L located on the X + side The width D1L and / or the width D1R in the X direction of the recess 16R located on the X-side may be different. The width D1C in the X direction of the depression 16C located in the center of the base material in the bottom view, the width D1L in the X direction of the depression 16L located on the X + side, and / or the width D1R in the X direction of the depression 16R located on the X− side. Even when they are different, the depths of the plurality of depressions in the Z direction may be the same or different. Moreover, it is preferable that the width D1L in the X direction of the depression 16L located on the X + side in the bottom view and the width D1R in the X direction of the depression 16R located on the X− side are substantially the same. By doing in this way, it becomes easy to suppress the bias | inclination of the joining member formed in the hollow 16L located in the X + side, and the joining member formed in the hollow 16R located in the X- side. Thereby, it becomes easy to suppress that the light emitting device is inclined and mounted on the mounting substrate.

  On the back surface, it is preferable that the plurality of depressions 16 be positioned symmetrically with respect to the center line of the base material parallel to the second direction (Y direction). By doing so, self-alignment effectively works when the light emitting device is mounted on the mounting substrate via the bonding member, and the light emitting device can be mounted with high accuracy within the mounting range.

  On the back surface, it is preferable that the opening shape of each of the plurality of depressions is substantially semicircular. A recess having a circular opening shape can be formed by drilling, and a substantially semicircular recess can be easily formed on the back surface by cutting a part of the circular recess by dicing or the like. . Moreover, since it can suppress that the stress which concerns on a hollow concentrates because the opening shape of a hollow is a substantially semicircle shape without a corner | angular part in a back surface, it can suppress that a base material cracks.

  As shown in FIGS. 1A, 2A, and 2B, the light emitting device 1000 may include a translucent member 30. The translucent member 30 is preferably located on the light emitting element 20. Since the translucent member is located on the light emitting element, the light emitting element 20 can be protected from external stress. The covering member 40 preferably covers the side surface of the translucent member 30. By doing in this way, the light from a light-emitting device can be brought close to a point light source. By bringing the light emitting device closer to the point light source, for example, adjustment of light distribution by an optical system such as a lens becomes easy.

  The light emitting element 20 includes a mounting surface facing the substrate 10 and a light extraction surface 201 positioned on the opposite side of the mounting surface. As shown in FIG. 2A, when the light-emitting element is flip-chip mounted, the surface where the positive and negative electrodes of the light-emitting element are located and the opposite surface are used as the light extraction surface. The translucent member 30 may be bonded to the light emitting element 20 via the light guide member 50. The light guide member 50 may be positioned only between the light extraction surface 201 of the light emitting element and the translucent member 30 to bond the light emitting element 20 and the covering member 40, or emit light from the light extraction surface 201 of the light emitting element. The light emitting element 20 and the covering member 40 may be bonded by covering up to the side surface 202 of the element. The light guide member 50 has a higher light transmittance from the light emitting element 20 than the covering member 40. For this reason, the light guide member 50 covers the side surface 202 of the light emitting element, so that light emitted from the side surface of the light emitting element 20 can be easily extracted to the outside of the light emitting device through the light guide member 50, thereby increasing light extraction efficiency. Can do.

  When there are a plurality of light emitting elements 20, the peak wavelengths of one light emitting element and the other light emitting element may be the same or different. When the peak wavelength of one light emitting element is different from that of the other light emitting element, the light emitting element has a light emission peak wavelength in a range of 430 nm to less than 490 nm (blue wavelength range) and the light emission peak wavelength of 490 nm to 570 nm. It is preferable that the light emitting element is in the range (wavelength range in the green region). In this way, the color rendering properties of the light emitting device can be improved.

  As shown in FIGS. 2A and 2B, the translucent member 30 may contain a wavelength converting substance 32. The wavelength converting material 32 is a member that absorbs at least a part of the primary light emitted from the light emitting element 20 and emits secondary light having a wavelength different from that of the primary light. By including the wavelength conversion material 32 in the translucent member 30, it is possible to output mixed color light in which the primary light emitted from the light emitting element 20 and the secondary light emitted from the wavelength conversion material 32 are mixed. For example, when a blue LED is used for the light emitting element 20 and a phosphor such as YAG is used for the wavelength conversion material 32, the blue light of the blue LED and yellow light emitted from the phosphor when excited by the blue light are mixed. It is possible to configure a light emitting device that outputs white light.

  The wavelength conversion material may be uniformly dispersed in the light transmissive member, or the wavelength conversion material may be unevenly distributed near the light emitting element rather than the upper surface of the light transmissive member 30. By doing in this way, even if it uses the wavelength conversion substance 32 weak to a water | moisture content, since the base material 31 of the translucent member 30 functions as a protective layer, degradation of the wavelength conversion substance 32 can be suppressed. 2A and 2B, the translucent member 30 may include a layer containing the wavelength converting substance 32 and a layer 33 substantially not containing the wavelength converting substance. Since the layer 33 that does not substantially contain the wavelength converting substance is positioned on the layer in which the translucent member 30 contains the wavelength converting substance 32, the layer 33 that does not substantially contain the wavelength converting substance can be used as the protective layer. Since the function is fulfilled, the deterioration of the wavelength converting substance 32 can be suppressed. An example of the wavelength converting substance 32 that is weak against moisture is a manganese-activated fluoride phosphor. Manganese-activated fluoride phosphors are preferable members from the viewpoint of color reproducibility because they can emit light with a relatively narrow spectral line width.

  As shown in FIG. 2B, the via hole 15 is provided in a hole that penetrates the front surface 111 and the back surface 112 of the base material 11. The via hole 15 includes a fourth wiring 151 covering the surface of the through hole of the base material and a filling member 152 filled in the fourth wiring 151. The filling member 152 may be conductive or insulating. It is preferable to use a resin material for the filling member 152. In general, the resin material before curing has a higher fluidity than the metal material before curing, so that the fourth wiring 151 is easily filled. For this reason, manufacture of a board | substrate becomes easy by using a resin material for a filling member. Examples of the resin material that can be easily filled include an epoxy resin. When using a resin material as the filling member, it is preferable to contain an additive member in order to lower the linear expansion coefficient. By doing so, the difference in the coefficient of linear expansion with the fourth wiring is reduced, so that it is possible to suppress the formation of a gap between the fourth wiring and the filling member due to heat from the light emitting element. Examples of the additive member include silicon oxide. In addition, when a metal material is used for the filling member 152, heat dissipation can be improved.

  As shown in FIG. 4A, the area of the via hole 15 on the back surface is smaller than the area of the opening of the recess 16 on the back surface. For this reason, although the via hole 15 has penetrated the base material 11, since it is smaller than the area of the opening part of the hollow 16 in a back surface, it can suppress that the intensity | strength of the base material 11 falls.

  As shown in FIG. 4A, it is preferable that the recess 16 is located between the via hole 15 and the adjacent via hole in the rear view. In other words, the recess 16 is preferably located on a straight line connecting the via hole 15 and the adjacent via hole in the rear view. By doing so, heat from the light emitting element can be efficiently transmitted from the via hole 15 to the third wiring 14 located in the recess 16. Since the heat transmitted to the third wiring 14 is transmitted to the mounting substrate through the bonding member, the heat dissipation of the light emitting device is improved.

  Moreover, as shown in FIG. 4A, it is preferable that the via hole 15 is located between the recess 16 and the adjacent recess in the rear view. In other words, it is preferable that the via hole 15 is located on a straight line connecting the recess 16 and the recess adjacent to the recess 16 in the rear view. By doing in this way, the heat from a light emitting element can be efficiently transmitted from the via hole 15 to the 3rd wiring 14 located in a hollow. Thereby, the heat dissipation of a light-emitting device improves.

  As shown in FIG. 2B, the light emitting element 20 includes at least a semiconductor stacked body 23, and positive and negative electrodes 21 and 22 are provided on the semiconductor stacked body 23. The positive and negative electrodes 21 and 22 are formed on the same surface of the light emitting element 20, and the light emitting element 20 is preferably flip-chip mounted on the substrate 10. This eliminates the need for a wire for supplying electricity to the positive and negative electrodes of the light emitting element, thereby reducing the size of the light emitting device. In the present embodiment, the light emitting element 20 includes the element substrate 24, but the element substrate 24 may be removed. When the light emitting element 20 is flip-chip mounted on the substrate 10, the positive and negative electrodes 21 and 22 of the light emitting element are connected to the first wiring 12 through the conductive adhesive member 60.

  As illustrated in FIG. 2B, when the light emitting device 1000 includes a plurality of light emitting elements 20, the plurality of light emitting elements are preferably provided side by side in the first direction (X direction). By doing so, the width of the light emitting device 1000 in the second direction (Y direction) can be shortened, so that the light emitting device can be thinned. The number of light emitting elements may be three or more or one.

  As shown in FIGS. 3C and 4A, the substrate 10 includes a base material 11, a first wiring 12, and a second wiring 13. The base material 11 includes a front surface 111 extending in a first direction that is a longitudinal direction and a second direction that is a short direction, a back surface 112 positioned on the opposite side of the front surface, and a bottom surface that is adjacent to the front surface 111 and orthogonal to the front surface 111. 113 and a top surface 114 located on the opposite side of the bottom surface 113.

  As illustrated in FIG. 4A, the light emitting device 1000 may include an insulating film 18 that covers a part of the second wiring 13. By providing the insulating film 18, it is possible to ensure insulation on the back surface and prevent a short circuit. Moreover, it can prevent that the 2nd wiring peels from a base material.

  As shown in FIG. 5A, the side surface 403 in the longitudinal direction of the covering member 40 located on the bottom surface 113 side is preferably inclined inward of the light emitting device 1000 in the Z direction. Thus, when the light emitting device 1000 is mounted on the mounting substrate, the contact between the side surface 403 of the covering member 40 and the mounting substrate is suppressed, and the mounting posture of the light emitting device 1000 is easily stabilized. Further, when the covering member 40 is thermally expanded, stress due to contact with the mounting board can be suppressed. The side surface 404 in the longitudinal direction of the covering member 40 located on the upper surface 114 side is preferably inclined inward of the light emitting device 1000 in the Z direction. By doing so, the contact between the side surface of the covering member 40 and the suction nozzle (collet) can be suppressed, and damage to the covering member 40 during the suction of the light emitting device 1000 can be suppressed. Further, when the light emitting device 1000 is incorporated in a lighting unit or the like, the upper surface 114 of the base material 11 is preferentially in contact with the peripheral member over the side surface 404 of the covering member 40, thereby suppressing the stress related to the covering member 40. be able to. As described above, the longitudinal side surface 403 of the covering member 40 positioned on the bottom surface 113 side and the longitudinal side surface 404 of the covering member 40 positioned on the top surface 114 side of the light emitting device 1000 from the back surface to the front surface (Z direction). It is preferable to incline inward. The inclination angle θ of the covering member 40 can be selected as appropriate, but from the viewpoint of the ease of exhibiting such an effect and the strength of the covering member 40, it is preferably 0.3 ° or more and 3 ° or less, and 0.5 ° It is more preferably 2 ° or less and more preferably 0.7 ° or more and 1.5 ° or less.

  As shown in FIGS. 5A and 5B, the right side surface and the left side surface of the light emitting device 1000 preferably have substantially the same shape. By doing so, the light emitting device 1000 can be reduced in size.

  As shown in FIG. 6, it is preferable that the lateral side surface 405 of the covering member 40 and the lateral side surface 105 of the substrate 10 are substantially on the same plane. By doing so, the width in the longitudinal direction (X direction) can be shortened, so that the light emitting device can be downsized.

<Embodiment 2>
The light-emitting device 2000 according to Embodiment 2 of the present invention illustrated in FIGS. 7 to 9B is less than the light-emitting device 1000 according to Embodiment 1 in the number of light-emitting elements placed on the substrate and the depressions included in the base material. And the number of via holes is different. The shape of the recess 16 is the same as that of the first embodiment.

  As shown in FIG. 8A, in the light emitting device 2000, as in the first embodiment, the depth of the recess in the front direction from the back surface is deeper on the bottom surface side than the upper surface side, so that the base material located on the upper surface side of the recess is The thickness can be made larger than the thickness of the substrate located on the bottom side of the recess. Thereby, the strength reduction of a base material can be suppressed. Moreover, since the volume of the joining member formed in a dent increases because the dent on the bottom side is deep, the bonding strength between the light emitting device 2000 and the mounting substrate can be improved.

  As shown in FIG. 8B, the number of light emitting elements may be one. Since the number of light emitting elements is one, the width in the first direction (X direction) can be shortened compared to the case where there are a plurality of light emitting elements, and thus the light emitting device can be downsized. As the width of the light emitting device in the first direction (X direction) becomes shorter, the number of depressions may be changed as appropriate. For example, as shown in FIG. 9A, the number of depressions 16 may be two. The number of the recesses 16 may be one or three or more.

  As shown in FIG. 9B, it is preferable that a plurality of via holes 15 are located between the depression 16 and the neighboring depression in the rear view. In other words, it is preferable that the plurality of via holes 15 be positioned on a straight line connecting the depressions 16 and the depressions adjacent to each other in the rear view. By doing in this way, the heat from a light emitting element can be efficiently transmitted from the via hole 15 to the 3rd wiring 14 located in a hollow. Thereby, the heat dissipation of a light-emitting device improves.

<Embodiment 3>
The light emitting device 3000 according to the third embodiment of the present invention shown in FIGS. 10 to 14 is different from the light emitting device 1000 according to the first embodiment in that it includes a recess 16 having a different shape.

  Similar to the light emitting device 1000, the light emitting device 3000 includes a substrate 10, at least one light emitting element 20, and a covering member 40. The substrate 10 includes a base material 11, a first wiring 12, a second wiring 13, a third wiring 14, and a via hole 15. The base material 11 includes a front surface 111 extending in a first direction that is a longitudinal direction and a second direction that is a short direction, a back surface 112 positioned on the opposite side of the front surface, and a bottom surface that is adjacent to the front surface 111 and orthogonal to the front surface 111. 113, a top surface 114 positioned on the opposite side of the bottom surface 113, and a side surface 115 positioned between the front surface 111 and the back surface 112. The substrate 11 further has a plurality of depressions 16. The plurality of depressions 16 include a central depression 161 that opens to the back surface 112 and the bottom surface 113, and an end depression 162 that opens to the back surface 112, the bottom surface 113, and the side surface 115. The third wiring 14 covers the inner wall of the recess 16 and is electrically connected to the second wiring 13.

  As illustrated in FIG. 14, the light emitting device 3000 includes the central depression 161 and / or the end portion in which the depth of the central depression 161 and / or the end depression 162 in the front direction from the back is deeper on the bottom surface side than the upper surface side. The thickness of the base material located on the upper surface side of the depression 162 can be made thicker than the thickness of the base material located on the bottom surface side of the central depression 161 and / or the end depression 162. Thereby, the strength reduction of a base material can be suppressed. Moreover, since the volume of the joining member formed in the center dent 161 and / or the end dent 162 is increased because the central dent 161 and / or the end dent 162 on the bottom surface side is deep, the light emitting device 3000 and the mounting substrate. The joint strength can be improved. It should be noted that at least one central recess 161 and / or end recess 162 may be provided.

  As shown in FIGS. 11 to 14, the end recess 162 is also opened on the side surface 115 of the base material. Thereby, since the joining member is located also on the side surface 115 side of the base material, the joining strength between the light emitting device 3000 and the mounting substrate can be further improved. In the case where the light emitting device 3000 is a side light emitting type in which the bottom surface 113 of the base material 11 and the mounting substrate are mounted to face each other, it is particularly preferable that the light emitting device 3000 includes an end recess 162. By providing the end recess 162, the side surface 115 of the base material can be fixed, so that the light emitting device 3000 is inclined on the mounting substrate, or the back surface of the base material is raised to face the mounting substrate. The occurrence of the Manhattan phenomenon can be suppressed. There may be at least one end recess 162, but a plurality of end recesses 162 are preferable. The presence of the plurality of end depressions 162 can further improve the bonding strength between the light emitting device 3000 and the mounting substrate. When there are a plurality of the end dents 162, it is preferable that the end dents are located at both ends of the substrate in the rear view. By doing in this way, generation | occurrence | production of the Manhattan phenomenon can be suppressed further.

  In the rear view, when the shape of the central depression 161 is a substantially semicircular shape that is a half of a circular shape, and the shape of the end depression 162 is a substantially quarter shape of a circular shape, The diameters of the circular shapes of the partial recesses 162 may be different or substantially the same. If the diameters of the circular shapes of the center recess 161 and the end recess 162 are substantially the same, it is preferable because the center recess 161 and the end recess 162 can be formed by one drill. Further, when the central depression 161 and the end depression 162 are provided with inclined portions that are inclined from the bottom surface 113 in the direction in which the thickness of the base material 11 is increased in cross-sectional view, the inclined portion and the end depression 162 of the central depression 161 are provided. The angles of the inclined portions may be different or substantially the same. If the angles of the inclined portion of the central recess 161 and the inclined portion of the end recess 162 are substantially the same, it is preferable because the central recess 161 and the end recess 162 can be formed by one drill.

  As shown in FIGS. 15 and 16, one translucent member 30 may be positioned on a plurality of light emitting elements. By doing in this way, since the area of the translucent member in front view can be enlarged, the light extraction efficiency of a light-emitting device improves. In addition, since the light emitting surface of the light emitting device becomes one, uneven luminance of the light emitting device can be reduced.

  When one translucent member 30 is positioned on a plurality of light emitting elements, the light guide members 50 that join each light emitting element 20 and the translucent member 30 are separated from each other even if they are connected. You may do it. As shown in FIG. 16, it is preferable that the light guide member is positioned so as to connect one light emitting element and the other light emitting element. By doing so, light from the light emitting element can be guided to the light transmitting member through the light guiding member from between the one light emitting element and the other light emitting element, thereby reducing luminance unevenness of the light emitting device. can do. In addition, since the portion of the covering member positioned between one light emitting element and the other light emitting element is reduced, the covering member can be prevented from being deteriorated by light from the light emitting element. The light guide member is preferably made of a material that is less likely to be deteriorated by light from the light emitting element than the covering member.

<Embodiment 4>
The light-emitting device 4000 according to the fourth embodiment of the present invention illustrated in FIGS. 17 to 21 is different from the light-emitting device 2000 according to the second embodiment in that it includes a recess 16 having a different shape.

  As shown in FIG. 21, the light emitting device 4000 includes an end recess 162. The depth of the end dent in the front direction from the back is deeper on the bottom side than the upper surface side, so that the thickness of the substrate located on the upper surface side of the end dent is larger than the thickness of the substrate located on the bottom side of the dent Can be thicker. Thereby, the strength reduction of a base material can be suppressed. Moreover, since the volume of the joining member formed in the end recess is increased due to the deep end recess on the bottom surface side, the bonding strength between the light emitting device 4000 and the mounting substrate can be improved.

  As shown in FIGS. 18 to 21, the end recess 162 is also opened on the side surface 115 of the base material. Thereby, since the joining member is located also on the side surface 115 side of the base material, the joining strength between the light emitting device 4000 and the mounting substrate can be further improved.

<Embodiment 5>
The light emitting device 5000 according to the fifth embodiment of the present invention illustrated in FIG. 22 is different from the light emitting device 4000 according to the fourth embodiment in that a central depression 161 is provided.

  Since the light emitting device 5000 includes the central recess 161 and the end recess 162, the number of places that can be fixed by the bonding member increases, and thus the bonding strength between the light emitting device and the mounting substrate can be improved. Note that the depth of the central depression 161 and / or the end depression 162 in the front direction from the back is deeper on the bottom side than on the top side. Thereby, the joint strength between the light emitting device 5000 and the mounting substrate can be improved.

<Embodiment 6>
The light-emitting device 6000 according to Embodiment 6 of the present invention illustrated in FIG. 23 has a second wiring and an insulating film shape and a depression (center depression) in the center of the light-emitting device, as compared with the light-emitting device 1000 according to Embodiment 1. It is different in that it does not have.

  The second wiring 13 of the light emitting device 6000 includes an exposed portion 131 that is located between the two end dents in the rear view and is exposed from the insulating film 18. The exposed portion 131 is surrounded by the insulating film 18 except for the bottom surface 113 side. By arranging the bonding member in the exposed portion 131, the bonding strength between the light emitting device and the mounting substrate can be improved. The shape of the exposed portion 131 in the rear view may be a rectangular shape, a hemispherical shape, or an arbitrary shape. The shape of the exposed portion 131 in the rear view can be easily changed by changing the shape of the insulating film. The shape of the exposed portion 131 in the rear view is preferably provided with the narrow portion 132 on the bottom surface side and the wide portion 133 at a position extended in the second direction (Y direction). By arranging the narrow portion, it is possible to suppress the flux contained in the bonding member from entering the light emitting element along the surface of the exposed portion 131 when the light emitting device is mounted. it can. The shape of the second wiring 13 exposed from the insulating film 18 is preferably positioned symmetrically with respect to the center line of the base material parallel to the second direction (Y direction). By doing so, self-alignment effectively works when the light emitting device is mounted on the mounting substrate via the bonding member, and the light emitting device can be mounted with high accuracy within the mounting range.

<Embodiment 7>
The light emitting device 7000 according to the seventh embodiment of the present invention illustrated in FIG. 24 differs from the light emitting device 4000 according to the fourth embodiment in the shapes of the second wiring and the insulating film.

  Similar to the light emitting device 6000, the second wiring 13 of the light emitting device 7000 includes an exposed portion 131 that is located between two end dents when viewed from the back and is exposed from the insulating film 18. The exposed portion 131 is surrounded by the insulating film 18 except for the bottom surface 113 side. By arranging the bonding member in the exposed portion 131, the bonding strength between the light emitting device 7000 and the mounting substrate can be improved.

  The shape of the land pattern of the mounting substrate on which the light emitting device is mounted is not particularly limited, and may be a substantially square shape or a substantially circular shape. For example, as illustrated in FIG. 25A, the land pattern of the mounting board on which the light emitting device according to Embodiment 1 is mounted may include a wide portion W10 that is wide in the X direction and a narrow portion W9 that is narrow in width. . When the narrow portion W9 is positioned at a position overlapping with the recess in the bottom view, the self-alignment property when the light emitting device is mounted on the mounting substrate can be enhanced. In addition, since the land pattern includes the wide portion W10, the area of the land pattern in the bottom view can be increased. Thereby, the variation in the thickness of a joining member can be suppressed. Further, as in the light emitting device according to the first embodiment, the land pattern of the mounting substrate on which the light emitting device in which the depth of the center of the recess is the maximum in the Z direction is as shown in FIG. 25B. The length W12 in the Z direction at the center of the land pattern is preferably longer than the length W11 in the Z direction at the end of the land pattern. By doing in this way, the self-alignment property when mounting a light-emitting device on a mounting substrate can be improved. As shown in FIG. 25C, the land pattern includes a wide portion W10 and a narrow portion W9, and the length W14 in the center Z direction in the narrow portion of the land pattern is the narrow portion of the land pattern. You may make it longer than length W13 in the Z direction of the edge part. By doing in this way, the self-alignment property at the time of mounting the light-emitting device which concerns on Embodiment 1 on a mounting board | substrate can be improved, and the variation in the thickness of a joining member can be suppressed.

  Further, as shown in FIG. 26A, the land pattern of the mounting board on which the light emitting device in which the depth of the depression in the Z direction becomes deeper as the distance from the center of the light emitting device is increased. The length W15 in the Z direction of the land pattern far from the center of the light emitting device is preferably longer than the length W16 in the Z direction of the land pattern near the center of the light emitting device. By doing in this way, the self-alignment property when mounting a light-emitting device on a mounting substrate can be improved. As shown in FIG. 26B, the land pattern includes a wide portion W10 that is wide in the X direction and a narrow portion W9 that is narrow in the X direction, and the narrow portion of the land pattern that is far from the center of the light emitting device. It is preferable that the length W17 in the Z direction of the end of the light source is longer than the length W18 in the Z direction of the end of the narrow portion of the land pattern closer to the center of the light emitting device. When the narrow portion is located at a position overlapping the end depression when viewed from the bottom, the self-alignment property when the light-emitting device is mounted on the mounting substrate can be enhanced. Further, since the land pattern includes the wide portion, the area of the land pattern in the bottom view can be increased. Thereby, the variation in the thickness of a joining member can be suppressed. Further, the length W17 in the Z direction of the end of the narrow portion of the land pattern far from the center of the light emitting device is the length in the Z direction of the end of the narrow portion of the land pattern near to the center of the light emitting device. By being longer than W18, the self-alignment property when the light emitting device is mounted on the mounting substrate can be improved.

<Embodiment 8>
The light emitting device 8000 according to the eighth embodiment of the present invention illustrated in FIGS. 27 to 30 is more than the light emitting device 1000 according to the first embodiment. And the number of via holes and the shape of the translucent member are different. The shape of the recess 16 is the same as that of the first embodiment.

  As shown in FIG. 28A, in the light emitting device 8000, as in the first embodiment, the depth of the recess in the front direction from the back surface is deeper on the bottom surface side than the upper surface side, so that the base material positioned on the upper surface side of the recess is The thickness can be made larger than the thickness of the substrate located on the bottom side of the recess. Thereby, the strength reduction of a base material can be suppressed. Moreover, since the volume of the bonding member formed in the depression increases because the depression on the bottom surface side is deep, the bonding strength between the light emitting device 8000 and the mounting substrate can be improved.

  As shown in FIG. 28B, the number of light emitting elements may be three. The peak wavelengths of the three light emitting elements may be the same, the peak wavelengths of the three light emitting elements may be different from each other, the peak wavelengths of the two light emitting elements are the same, and the peak wavelength of one light emitting element is the same as that of the two light emitting elements. It may be different from the peak wavelength. In the present specification, the same peak wavelength of the light emitting element means that a variation of about 5 nm is allowed. When the peak wavelengths of the light emitting elements are different, as shown in FIG. 28B, the first light emitting element 20B in which the peak wavelength of light emission is in the range of 430 nm to less than 490 nm (the wavelength range of the blue region) and the peak wavelength of light emission are It is preferable to include the second light emitting element 20G in the range of 490 nm or more and 570 nm or less (the wavelength range of the green region). In particular, the second light emitting element 20G is preferably a light emitting element having a half width of 40 nm or less, and more preferably a light emitting element having a half width of 30 nm or less. Thereby, compared with the case where green light is obtained using a green phosphor, green light can easily have a sharp peak. As a result, the liquid crystal display device including the light emitting device 8000 can achieve high color reproducibility.

  The arrangement of the first light emitting element 20B and the second light emitting element 20G is not particularly limited, but as shown in FIG. 28B, the first light emitting element 20B that is a blue light emitting element and the second light emitting element that is a green light emitting element in order from the left. 20G and the first light emitting element 20B which is a blue light emitting element are preferably arranged side by side. By arranging the first light emitting elements 20B and the second light emitting elements 20G alternately, the color mixing property of the light emitting device can be improved. Note that the second light emitting element, the first light emitting element, and the second light emitting element may be arranged in order from the left. Further, depending on the light emission characteristics to be obtained, the number of the first light emitting elements 20B may be larger than the number of the second light emitting elements 20G, and the number of the second light emitting elements 20G is the first light emitting element. The number of first light emitting elements 20B and the number of second light emitting elements 20G may be the same. By adjusting the number of light-emitting elements, a light-emitting device having an arbitrary color tone and light amount can be obtained.

As shown in FIG. 28B, when one translucent member 30 is positioned on the first light emitting element 20B and the second light emitting element 20G, the wavelength conversion material 32 absorbs the green light of the second light emitting element 20G. Thus, it is preferable that red light is hardly emitted. That is, it is preferable that the wavelength conversion material 32 does not substantially convert green light into red light. And it is preferable that the reflectance with respect to the green light of the wavelength conversion substance 32 is 70% or more on the average in the wavelength range of green light. By making the wavelength conversion material 32 a phosphor that has a high reflectance with respect to green light, that is, a phosphor that hardly absorbs green light, that is, a phosphor that hardly converts the wavelength of green light, the design of the light emitting device is facilitated. can do.
If a red phosphor having a large green light absorption is used, not only the first light emitting element 20B but also the second light emitting element 20G must consider the output balance of the light emitting device in consideration of the wavelength conversion by the wavelength converting material 32. Absent. On the other hand, when the wavelength converting material 32 that hardly converts the wavelength of green light is used, the output balance of the light emitting device can be designed only by considering the wavelength conversion of the blue light emitted by the first light emitting element 20B.

Examples of such a preferable wavelength conversion substance 32 include the following red phosphors. The wavelength converting material 32 is at least one of these.
The first type is a red phosphor whose composition is represented by the following general formula (I).

A ₂ MF ₆ : Mn ⁴⁺ (I)

However, in the said general formula (I), A is at least 1 sort (s) chosen from the group which consists of K, Li, Na, Rb, Cs, and NH4 ⁺ , M is from a group 4 element and a group 14 element. And at least one element selected from the group consisting of

Group 4 elements are titanium (Ti), zirconium (Zr), and hafnium (Hf). Group 14 elements are silicon (Si), germanium (Ge), tin (Sn), and lead (Pb).
Specific examples of the first type of red phosphor include K ₂ SiF ₆ : Mn ⁴⁺ , K ₂ (Si, Ge) F ₆ : Mn ⁴⁺ , and K ₂ TiF ₆ : Mn ⁴⁺ .

The second type is a red phosphor whose composition is represented by 3.5MgO.0.5MgF ₂ .GeO ₂ : Mn ⁴⁺ or a red phosphor whose composition is represented by the following general formula (II) .

(X-a) MgO.a (Ma) O.b / 2 (Mb) ₂ O ₃ .yMgF ₂ .c (Mc) X _2. (1-de) GeO ₂ .d (Md) O _2. e (Me) ₂ O ₃ : Mn ⁴⁺ (II)

However, in the general formula (II), Ma is at least one selected from Ca, Sr, Ba, and Zn, Mb is at least one selected from Sc, La, and Lu, and Mc is , Ca, Sr, Ba, Zn, X is at least one selected from F, Cl, and Md is at least one selected from Ti, Sn, Zr And Me is at least one selected from B, Al, Ga, and In. For x, y, a, b, c, d, and e, 2 ≦ x ≦ 4, 0 <y ≦ 2, 0 ≦ a ≦ 1.5, 0 ≦ b <1, 0 ≦ c ≦ 2, 0 ≦ d ≦ 0.5 and 0 ≦ e <1.

  Since the light emitting device 8000 has three light emitting elements, the width in the first direction (X direction) tends to be longer than that in the case where there is one light emitting element. For this reason, you may change suitably the number of a hollow and a via hole. For example, as shown in FIG. 30, the number of recesses 16 and via holes may be four.

  As shown in FIG. 31, one translucent member 30 may be positioned on each of the first light emitting element and the second light emitting element. As shown in FIG. 28B, one translucent member 30 is provided. However, it may be located on a plurality of light emitting elements. When one translucent member 30 is positioned on each of the first light emitting element and the second light emitting element as shown in FIG. 31, the translucent member 30 positioned on the first light emitting element 20B and The material of the wavelength conversion substance 32 contained in the translucent member 30 located on the second light emitting element 20G may be the same or different. For example, when the wavelength converting material 32 hardly absorbs the green light of the second light emitting element 20G and emits red light, the translucent member 30 positioned on the first light emitting element 20B has red fluorescence. The translucent member 30 that contains the wavelength conversion substance 32 that is a body and is located on the second light emitting element 20G may not contain the wavelength conversion substance 32 that is a red phosphor. By doing so, it is possible to design the output balance of the light emitting device only by considering only the wavelength conversion of the blue light emitted by the first light emitting element 20B. When one translucent member 30 is positioned on each of the first light emitting element and the second light emitting element, the translucent member 30 positioned on the first light emitting element 20B and the second light emitting element 20G A covering member is formed between the translucent member 30 located at the position. As shown in FIG. 28B, when one translucent member 30 is positioned on a plurality of light emitting elements, the area of the translucent member 30 in the front view can be increased, so that the light of the light emitting device Extraction efficiency is improved. In addition, since the light emitting surface of the light emitting device becomes one, uneven luminance of the light emitting device can be reduced.

  When one translucent member 30 is positioned on a plurality of light emitting elements, the light guide members 50 that join each light emitting element 20 and the translucent member 30 are separated from each other even if they are connected. You may do it. As shown in FIG. 28B, the light guide member 50 is preferably positioned so as to connect one light emitting element and the other light emitting element. By doing so, light from the light emitting element can be guided to the light transmitting member through the light guiding member from between the one light emitting element and the other light emitting element, thereby reducing luminance unevenness of the light emitting device. can do.

  As shown in FIGS. 28B and 31, the translucent member 30 may include a layer containing the wavelength converting substance 32 and a layer 33 substantially not containing the wavelength converting substance. Since the layer 33 that does not substantially contain the wavelength converting substance is positioned on the layer in which the translucent member 30 contains the wavelength converting substance 32, the layer 33 that does not substantially contain the wavelength converting substance can be used as the protective layer. Since the function is fulfilled, the deterioration of the wavelength converting substance 32 can be suppressed. When one translucent member 30 is positioned on each of the first light emitting element and the second light emitting element as shown in FIG. 31, the translucent member 30 positioned on the first light emitting element 20B. The thickness of the layer 33 that does not substantially contain the wavelength converting material of the light transmitting member 30 is different from the thickness of the layer 33 that does not substantially contain the wavelength converting material of the translucent member 30 positioned on the second light emitting element 20G. Also good. In addition, when one translucent member 30 is positioned on each of the first light emitting element and the second light emitting element, the wavelength converting substance of the translucent member 30 positioned on the first light emitting element 20B. The thickness of the layer containing 32 and the thickness of the layer containing the translucent member 30 wavelength conversion substance 32 located on the second light emitting element 20G may be the same or different. In the present specification, the same thickness means that a difference of about 5 μm is allowed.

  Hereinafter, each component in the light-emitting device which concerns on one Embodiment of this invention is demonstrated.

(Substrate 10)
The substrate 10 is a member on which the light emitting element is placed. The substrate 10 includes at least a base material 11, a first wiring 12, a second wiring 13, a third wiring 14, and a via hole 15.

(Substrate 11)
The base material 11 can be comprised using insulating members, such as resin or fiber reinforced resin, ceramics, and glass. Examples of the resin or fiber reinforced resin include epoxy, glass epoxy, bismaleimide triazine (BT), and polyimide. Examples of the ceramic include aluminum oxide, aluminum nitride, zirconium oxide, zirconium nitride, titanium oxide, titanium nitride, or a mixture thereof. Of these substrates, it is particularly preferable to use a substrate having physical properties close to the linear expansion coefficient of the light emitting element. The lower limit of the thickness of the substrate can be selected as appropriate, but is preferably 0.05 mm or more and more preferably 0.2 mm or more from the viewpoint of the strength of the substrate. The upper limit value of the thickness of the base material is preferably 0.5 mm or less, and more preferably 0.4 mm or less, from the viewpoint of the thickness (depth) of the light emitting device.

(First wiring 12, second wiring 13, third wiring 14)
The first wiring is disposed on the front surface of the substrate and is electrically connected to the light emitting element. The second wiring is disposed on the back surface of the substrate and is electrically connected to the first wiring through the via hole. The third wiring covers the inner wall of the recess and is electrically connected to the second wiring. The first wiring, the second wiring, and the third wiring can be formed of copper, iron, nickel, tungsten, chromium, aluminum, silver, gold, titanium, palladium, rhodium, or an alloy thereof. A single layer or a multilayer of these metals or alloys may be used. In particular, copper or a copper alloy is preferable from the viewpoint of heat dissipation. Further, the surface layer of the first wiring and / or the second wiring is a layer of silver, platinum, aluminum, rhodium, gold, or an alloy thereof from the viewpoint of wettability and / or light reflectivity of the conductive adhesive member. May be provided.

(Via hole 15)
The via hole 15 is a member that is provided in a hole penetrating the front surface and the back surface of the substrate 11 and electrically connects the first wiring and the second wiring. The via hole 15 includes a fourth wiring 151 that covers the surface of the through hole of the base material, and a filling member 152 that fills the fourth wiring 151. For the fourth wiring 151, a conductive member similar to the first wiring, the second wiring, and the third wiring can be used. As the filling member 152, a conductive member or an insulating member may be used.

(Insulating film 18)
The insulating film 18 is a member that ensures insulation on the back surface and prevents a short circuit. The insulating film may be formed of any of those used in the field. For example, a thermosetting resin or a thermoplastic resin can be used.

(Light emitting element 20)
The light emitting element 20 is a semiconductor element that emits light by applying a voltage, and a known semiconductor element composed of a nitride semiconductor or the like can be applied. Examples of the light emitting element 20 include an LED chip. The light emitting element 20 includes at least a semiconductor laminate 23, and in many cases further includes an element substrate 24. The top view shape of the light emitting element is preferably a rectangle, particularly a square shape or a rectangular shape that is long in one direction, but may be other shapes. For example, if it is a hexagonal shape, the light emission efficiency can be increased. The side surface of the light emitting element may be perpendicular to the upper surface, or may be inclined inward or outward. The light emitting element has positive and negative electrodes. The positive and negative electrodes can be composed of gold, silver, tin, platinum, rhodium, titanium, aluminum, tungsten, palladium, nickel, or an alloy thereof. The emission peak wavelength of the light-emitting element can be selected from the ultraviolet region to the infrared region depending on the semiconductor material and its mixed crystal ratio. As the semiconductor material, it is preferable to use a nitride semiconductor, which is a material capable of emitting light with a short wavelength that can efficiently excite the wavelength conversion substance. The nitride semiconductor is mainly represented by a general formula In _x Al _y Ga _1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1). The emission peak wavelength of the light-emitting element is preferably 400 nm or more and 530 nm or less, more preferably 420 nm or more and 490 nm or less, and more preferably 450 nm or more and 475 nm or less, from the viewpoints of light emission efficiency, excitation of the wavelength converting substance and color mixing relationship with the emission. Even more preferable. In addition, an InAlGaAs-based semiconductor, an InAlGaP-based semiconductor, zinc sulfide, zinc selenide, silicon carbide, or the like can also be used. The element substrate of the light emitting element is a crystal growth substrate capable of mainly growing a semiconductor crystal constituting the semiconductor stacked body, but may be a bonding substrate bonded to a semiconductor element structure separated from the crystal growth substrate. . Since the element substrate has a light-transmitting property, it is easy to adopt flip chip mounting, and it is easy to increase the light extraction efficiency. Examples of the base material of the element substrate include sapphire, gallium nitride, aluminum nitride, silicon, silicon carbide, gallium arsenide, gallium phosphide, indium phosphide, zinc sulfide, zinc oxide, zinc selenide, diamond and the like. Of these, sapphire is preferable. The thickness of the element substrate can be appropriately selected, and is, for example, 0.02 mm or more and 1 mm or less. From the viewpoint of the strength of the element substrate and / or the thickness of the light emitting device, it is preferably 0.05 mm or more and 0.3 mm or less. .

(Translucent member 30)
The translucent member is a member that is provided on the light emitting element and protects the light emitting element. The translucent member is composed of at least the following base material. Moreover, the translucent member can function as a wavelength conversion substance by containing the following wavelength conversion substance 32 in a base material. Even when the translucent member includes a layer containing a wavelength converting substance and a layer substantially not containing the wavelength converting substance, the base material of each layer is configured as follows. The base material of each layer may be the same or different. However, it is not essential that the translucent member has a wavelength converting substance. The translucent member may be a sintered body of a wavelength conversion material and an inorganic material such as alumina, or a plate crystal of the wavelength conversion material.

(Base material 31 of translucent member)
The base material 31 of the translucent member may be any material that has translucency with respect to light emitted from the light emitting element. The “translucency” means that the light transmittance at the emission peak wavelength of the light emitting element is preferably 60% or more, more preferably 70% or more, and still more preferably 80% or more. Say that. As the base material of the translucent member, a silicone resin, an epoxy resin, a phenol resin, a polycarbonate resin, an acrylic resin, or a modified resin thereof can be used. Glass may be used. Of these, silicone resins and modified silicone resins are preferred because they are excellent in heat resistance and light resistance. Specific examples of the silicone resin include dimethyl silicone resin, phenyl-methyl silicone resin, and diphenyl silicone resin. The translucent member can be constituted by laminating one of these base materials as a single layer or by laminating two or more of these base materials. The “modified resin” in this specification includes a hybrid resin.

The base material of the translucent member may contain various fillers in the resin or glass. Examples of the filler include silicon oxide, aluminum oxide, zirconium oxide, and zinc oxide. A filler can be used individually by 1 type of these or in combination of 2 or more types of these. In particular, silicon oxide having a small thermal expansion coefficient is preferable. Further, by using nanoparticles as the filler, scattering of light emitted from the light emitting element can be increased, and the amount of the wavelength converting substance used can be reduced. Nanoparticles are particles having a particle size of 1 nm to 100 nm. Further, "particle size" herein, for example, it is defined by the D _50.

(Wavelength converting material 32)
The wavelength converting material absorbs at least a part of the primary light emitted from the light emitting element and emits secondary light having a wavelength different from that of the primary light. The wavelength converting substance can be used alone or in combination of two or more of the specific examples shown below.

Examples of wavelength converting substances that emit green light include yttrium / aluminum / garnet phosphors (for example, Y ₃ (Al, Ga) ₅ O ₁₂ : Ce) and lutetium / aluminum / garnet phosphors (for example, Lu ₃ (Al, Ga)). ₅ O ₁₂ : Ce), terbium / aluminum / garnet phosphor (for example, Tb ₃ (Al, Ga) ₅ O ₁₂ : Ce) phosphor, silicate phosphor (for example (Ba, Sr) ₂ SiO ₄ : Eu) ), Chlorosilicate phosphor (for example, Ca ₈ Mg (SiO ₄ ) ₄ Cl ₂ : Eu), β sialon phosphor (for example, Si _6-z Al _z O _z N _8-z : Eu (0 <z <4 .2)), SGS-based phosphors (for example, SrGa ₂ S ₄ : Eu) and the like. As a wavelength conversion substance for yellow light emission, an α sialon-based phosphor (for example, M _z (Si, Al) ₁₂ (O, N) ₁₆ (where 0 <z ≦ 2 and M is Li, Mg, Ca, Y) In addition, among the wavelength conversion materials emitting green light, there are also wavelength conversion materials emitting yellow light, such as yttrium, aluminum, and garnet phosphors. The emission peak wavelength can be shifted to the longer wavelength side by substituting a part of Y with Gd, and yellow light emission is possible, and among these, wavelength conversion substances capable of orange light emission are also included. Examples of wavelength converting substances that emit red light include nitrogen-containing calcium aluminosilicate (CASN or SCASN) phosphors (for example, (Sr, Ca) AlSiN ₃ : Eu). In addition, a manganese-activated fluoride-based phosphor (general formula (I) A ₂ [M _1-a Mn _a F ₆ ] is a phosphor represented by the formula (I) wherein A is K , Li, Na, Rb, Cs and NH ₄ , M is at least one element selected from the group consisting of Group 4 elements and Group 14 elements, and a As a typical example of this manganese-activated fluoride phosphor, there is a manganese-activated potassium fluorosilicate phosphor (for example, K ₂ SiF ₆ : Mn). .

(Coating member 40)
From the viewpoint of upward light extraction efficiency, the light-reflecting coating member preferably has a light reflectance at the emission peak wavelength of the light-emitting element of 70% or more, more preferably 80% or more, and 90 % Or more is even more preferable. Furthermore, the covering member is preferably white. Therefore, the covering member preferably contains a white pigment in the base material. The covering member is in a liquid state before being cured. The covering member can be formed by transfer molding, injection molding, compression molding, potting, or the like.

(Base material for covering member)
Resin can be used for the base material of a covering member, for example, a silicone resin, an epoxy resin, a phenol resin, a polycarbonate resin, an acrylic resin, or these modified resins are mentioned. Of these, silicone resins and modified silicone resins are preferred because they are excellent in heat resistance and light resistance. Specific examples of the silicone resin include dimethyl silicone resin, phenyl-methyl silicone resin, and diphenyl silicone resin. Moreover, the base material of the covering member may contain the same filler as the above-described translucent member.

(White pigment)
White pigments include titanium oxide, zinc oxide, magnesium oxide, magnesium carbonate, magnesium hydroxide, calcium carbonate, calcium hydroxide, calcium silicate, magnesium silicate, barium titanate, barium sulfate, aluminum hydroxide, aluminum oxide, zirconium oxide, One of silicon oxides can be used alone, or two or more of these can be used in combination. The shape of the white pigment can be appropriately selected and may be indefinite or crushed, but is preferably spherical from the viewpoint of fluidity. The particle size of the white pigment is, for example, about 0.1 μm or more and 0.5 μm or less, but it is preferable that the white pigment is smaller in order to enhance the effect of light reflection and coating. The content of the white pigment in the light-reflective coating member can be selected as appropriate. However, from the viewpoint of light reflectivity and viscosity in a liquid state, for example, it is preferably 10 wt% or more and 80 wt% or less, and 20 wt% or more and 70 wt% or less. More preferably, it is 30 wt% or more and 60 wt% or less. Note that “wt%” is weight percent and represents the ratio of the weight of the material to the total weight of the light-reflective coating member.

(Light guide member 50)
The light guide member is a member that bonds the light emitting element and the translucent member and guides light from the light emitting element to the translucent member. Examples of the base material of the light guide member include silicone resin, epoxy resin, phenol resin, polycarbonate resin, acrylic resin, and modified resins thereof. Of these, silicone resins and modified silicone resins are preferred because they are excellent in heat resistance and light resistance. Specific examples of the silicone resin include dimethyl silicone resin, phenyl-methyl silicone resin, and diphenyl silicone resin. Moreover, the base material of the light guide member may contain the same filler as the above-described translucent member. Further, the light guide member can be omitted.

(Conductive adhesive member 60)
The conductive adhesive member is a member that electrically connects the electrode of the light emitting element and the first wiring. Examples of conductive adhesive members include gold, silver, copper and other bumps, silver, gold, copper, platinum, aluminum, metal paste including resin binder, tin-bismuth, tin-copper, tin -Any one of solders such as silver-based, gold-tin-based solders, and low melting point metals can be used.

  A light emitting device according to an embodiment of the present invention includes a backlight device for a liquid crystal display, various lighting fixtures, a large display, various display devices such as advertisements and destination guides, a projector device, a digital video camera, a facsimile machine, and a copier. It can be used for an image reading device in a scanner or the like.

1000, 2000 Light emitting device 10 Substrate 11 Base material 12 First wiring 13 Second wiring 14 Third wiring 15 Via hole
151 4th wiring
152 Filling member 16 Dimple 18 Insulating film 20 Light emitting element 30 Translucent member 40 Cover member 50 Light guide member 60 Conductive adhesive member

Claims (13)

A front surface extending in a first direction that is a longitudinal direction and a second direction that is a short direction; a back surface that is located on the opposite side of the front surface; a bottom surface that is adjacent to the front surface and that is orthogonal to the front surface; A base material having an upper surface located on the opposite side; a first wiring disposed on the front; a second wiring disposed on the back; and electrically connecting the first wiring and the second wiring. A via hole, and a substrate comprising:
At least one light-emitting element electrically connected to the first wiring and placed on the first wiring;
A light-reflective coating member that covers a side surface of the light-emitting element and a front surface of the substrate,
It said substrate has a plurality of recesses opening into said bottom surface and said rear surface,
The plurality of depressions are separated from the via hole in a front view,
The substrate includes a third wiring that covers inner walls of the plurality of depressions and is electrically connected to the second wiring;
Each of the depths of the plurality of depressions in the front direction from the back surface is a light emitting device that is deeper on the bottom surface side than the top surface side.   The light emitting device according to claim 1, wherein a central depth of each of the plurality of depressions is maximum on the bottom surface.   3. The light emitting device according to claim 1, wherein each of the plurality of depressions has a semicircular shape on the back surface.   4. The light-emitting device according to claim 1, wherein the maximum depth of each of the plurality of recesses is 0.4 to 0.8 times the thickness of the base material. 5.   5. The light-emitting device according to claim 1, wherein each of the plurality of depressions has the same shape on the back surface.   6. The light emitting device according to claim 1, wherein, on the back surface, the plurality of depressions are positioned symmetrically with respect to a center line of the base material parallel to the second direction.   The light emitting device according to claim 1, wherein a translucent member is positioned on the light emitting element.   The light emitting device according to claim 7, wherein the covering member covers a side surface of the translucent member.   9. The light-emitting device according to claim 1, wherein a side surface in the short direction of the covering member and a side surface in the short direction of the substrate are substantially on the same plane.   The light emitting device according to claim 1, comprising a plurality of the light emitting elements, wherein the plurality of light emitting elements are provided side by side in the first direction.   The light emitting device according to claim 1, wherein the via hole includes a fourth wiring and a filling member, and the filling member is a resin material.   The said base material is provided with the side surface located between the said front surface and the said back surface, At least 1 of the said several hollow is an edge part hollow opened to the said back surface, the said bottom surface, and the said side surface. The light-emitting device of any one of Claims.   The light-emitting device according to claim 12, comprising a plurality of the end dents, wherein the end dents are located at both ends of the substrate in a rear view.

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