JP6724933B2 - Method for manufacturing light emitting device - Google Patents

Description

The present disclosure relates to a light emitting device.

There is known a light emitting device in which a side surface of the light emitting element is covered with a reflective member instead of providing a housing for housing the light emitting element (for example, Patent Documents 1 to 4). In these light emitting devices, a translucent member is arranged between the light emitting element and the reflective member, and the light emitted from the side surface of the light emitting element is extracted to the light emitting surface side of the light emitting device through the translucent member. Thus, the light extraction efficiency of the light emitting device is improved.

JP 2012-227470 A JP, 2013-012545, A International Publication No. 2013/005646 JP, 2010-219324, A

If a translucent member is provided between the light emitting element and the reflective member, the translucent member may be separated from the light emitting element. This peeling changes the optical characteristics of the interface between the light emitting element and the light transmissive member, so that the light amount and the light distribution of the light extracted through the light transmissive member may change. That is, since the light extraction efficiency and the light distribution characteristics of the light emitting device may change due to the peeling of the translucent member, the quality of the light emitting device may not be constant, and sufficient reliability may not be guaranteed. Therefore, an object of the present invention is to provide a highly reliable light emitting device by suppressing peeling between a light transmissive member and a light emitting element.

Therefore, the light emitting device according to the embodiment of the present invention is
A first surface, a second surface facing the first surface, and a plurality of side surfaces between the first surface and the second surface, and the second surface and the second surface. A light emitting element having a plurality of corners that are in contact with two of a plurality of side surfaces and having a pair of electrodes on the second surface side;
A translucent member that covers a part of at least one of the side surfaces and a part of a side where the at least one side surface and the second surface contact each other so as to expose one or more of the plurality of corner portions. ,
In order to expose the pair of electrodes, a covering member that covers the exposed corner portion of the light emitting element and the outer surface of the translucent member is included,
A difference in thermal expansion coefficient between the covering member and the light emitting element is smaller than a difference in thermal expansion coefficient between the light transmissive member and the light emitting element.

According to one embodiment of the present invention, it is possible to prevent the translucent member from peeling from the light emitting element, and improve the reliability of the light emitting device.

FIG. 1 is a schematic plan view of the light emitting device according to the first embodiment. 2A is a schematic sectional view taken along the line AA of FIG. 1, and FIG. 2B is a schematic sectional view taken along the line BB of FIG. FIG. 3 is a schematic perspective view showing the light emitting device according to the first embodiment, in which the covering member is omitted and the translucent member is exposed. FIG. 4 is a schematic bottom view of the light emitting device according to the first embodiment. 5A to 5C are schematic cross-sectional views for explaining the first manufacturing method of the light emitting device according to the first embodiment. FIG. 6A and FIG. 6B are schematic plan views for explaining the second manufacturing method of the light emitting device according to the first embodiment. 7A and 7B are schematic plan views for explaining the second manufacturing method of the light emitting device according to the first embodiment. FIG. 8 is a schematic plan view for explaining the second manufacturing method of the light emitting device according to the first embodiment. 9A is a schematic sectional view taken along the line CC of FIG. 6A, and FIG. 9B is a schematic sectional view taken along the line D-D of FIG. 6B. 7C is a schematic cross-sectional view taken along the line EE of FIG. 10A is a schematic cross-sectional view taken along the line FF of FIG. 7B, and FIG. 10B is a schematic cross-sectional view taken along the line GG of FIG. 11A and 11B are schematic plan views for explaining the third manufacturing method of the light emitting device according to the first embodiment. FIG. 12A is a schematic sectional view taken along the line H-H of FIG. 11A, and FIG. 12B is a schematic sectional view taken along the line I-I of FIG. 11B. 13A to 13C are schematic cross-sectional views for explaining the third method for manufacturing the light emitting device according to the first embodiment. 14(a) to 14(c) are schematic cross-sectional views for explaining a third different manufacturing method of the light emitting device according to the first embodiment. 15A is a schematic plan view of the light emitting device according to the second embodiment, and FIG. 15B is a schematic cross-sectional view taken along the line JJ of FIG. 15A is a schematic sectional view taken along the line KK of FIG. 16A to 16E are schematic cross-sectional views for explaining the method for manufacturing the light emitting device according to the second embodiment. 17A to 17D are schematic cross-sectional views for explaining the method for manufacturing the light emitting device according to the second embodiment. FIG. 18 is a schematic perspective view of the light emitting device according to the third embodiment. FIG. 19 is a schematic plan view showing the light emitting device according to the third embodiment, in which the covering member is omitted and the translucent member is exposed. FIG. 20 is a schematic perspective view showing the light emitting device according to the third embodiment, in which the covering member is omitted and the translucent member is exposed. 21A and 21B are drawings for explaining a size and shape suitable for a translucent member of a light emitting device, FIG. 21A is a schematic plan view of the light emitting device, and FIG. 21B is a schematic plan view of FIG. 21A. It is a schematic sectional drawing along the LL line.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description, a term indicating a specific direction or position (for example, “upper”, “lower”, “right”, “left” and another term including those terms) is used as necessary. .. The use of those terms is for facilitating the understanding of the invention with reference to the drawings, and the technical scope of the present invention is not limited by the meanings of the terms. Further, the same reference numerals appearing in a plurality of drawings indicate the same parts or members.

<Embodiment 1>
The light emitting device 10 according to the present embodiment shown in FIGS. 1, 2A, and 2B includes a light emitting element 20, a translucent member 30 provided on the side surface 23 side of the light emitting element 20, and a light transmissive member 30. The covering member 40 that covers the outer surface 33 of the elastic member 30. The light emitting device 10 may include the wavelength conversion member 50 on the first surface (upper surface) 11 side that functions as a light emitting surface.

2A is a schematic cross-sectional view taken along the line AA of FIG. 1 (a line orthogonal to the pair of facing side surfaces 23 of the light emitting element 20). FIG. 2B is a schematic cross-sectional view taken along line BB of FIG. 1 (a line corresponding to a diagonal line of the light emitting element 20 having a rectangular shape in a top view). As shown in FIGS. 2A and 2B, the light emitting element 20 may include a transparent substrate 27 and a semiconductor laminated body 28 formed on the lower surface side of the transparent substrate 27. The light emitting element 20 includes a first surface (upper surface) 21 on the transparent substrate 27 side, a second surface (lower surface) 22 on the semiconductor laminated body 28 side facing the first surface 21, and a first surface. It has a plurality of side surfaces 23 between the first surface 21 and the second surface 22. The light emitted from the light emitting element 20 passes through the semiconductor laminated body 28 through the transparent substrate 27, or from the semiconductor laminated body 28 through the side surface 23 of the light emitting element 20 and the transparent member 30. 1 is taken out to the side of the surface 11.

A pair of electrodes 251 and 252 for energizing the light emitting element 20 are provided on the second surface 22 of the light emitting element 20 (on the semiconductor laminated body 28 side in FIGS. 2A and 2B ). Note that, in this specification, the “second surface 22” of the light emitting element 20 refers to the surface of the light emitting element 20 in a state where the electrodes 251 and 252 are not included. In the present embodiment, the second surface 22 coincides with the lower surface of the semiconductor stacked body 28.

Each of the two electrodes 251 and 252 forming the pair of electrodes can have any shape. For example, in the light emitting device 10 shown in FIG. 4, the electrodes 251 and 252 are arranged in one direction (y direction) when viewed from the second surface 12 side of the light emitting device 10 (that is, when viewed along the z direction). ) Can be a rectangle that extends. The electrodes 251 and 252 do not have to have the same shape. Further, the two electrodes 251 and 252 can be arbitrarily arranged as long as they are separated from each other. In FIG. 4, the two electrodes 251 and 252 are arranged in parallel along the y direction.

Referring again to FIG. 2A, the translucent member 30 covers the side surface 23 of the light emitting element 20, and guides the light emitted from the side surface 23 toward the first surface 11 of the light emitting device 10. To do. That is, before the light reaching the side surface 23 of the light emitting element 20 is reflected by the side surface 23 and is attenuated in the light emitting element 20, the light can be extracted to the outside of the light emitting element 20 through the translucent member 30. By providing the translucent member 30, it is possible to suppress the loss of light and improve the light extraction efficiency of the light emitting device 10.

In particular, when the side surface 23 of the light emitting element 20 is inclined with respect to the second surface 22, the effect of the translucent member 30 becomes remarkable. For example, in the manufacturing process of the light emitting element 20, when the light emitting element 20 is divided into individual pieces by cleavage, the side surface 23 of the light emitting element 20 may not be perpendicular to the second surface 22. In general, the light emitting element 20 has a parallelogram shape in a cross section (FIG. 2A) taken along the line AA of FIG. That is, the first surface 21 and the second surface 22 are parallel to each other, the two side surfaces 23 facing each other are parallel to each other, and each side surface 23 emits light inclined with respect to the first surface 21 and the second surface 22. It becomes the element 20. Since the angle formed between the one side surface 23 and the second surface 22 is an obtuse angle, the light reflected by the one side surface 23 is directed toward the first surface 21 of the light emitting element 20 as it is in the light emitting device 10. It can be taken out. However, the other side surface 23 forms an acute angle with the second surface 22, so that the light reflected by the other side surface 23 travels toward the second surface 22 in the light emitting element 20. Can decay.
By covering the other side surface 23 with the translucent member 30, the light reaching the other side surface 23 can be extracted to the outside of the light emitting device 10 through the translucent member 30.

FIG. 3 shows the light emitting device 10 in a state in which the covering member 40 is omitted in order to make it easy to grasp the covering state of the light emitting element 20 with the translucent member 30. Further, in order to make it easier to visually recognize the corner portion where the second surface 22 of the light emitting element 20 and the two side surfaces 23 are in contact (this is referred to as the “corner portion on the second surface 22 side”), the light emitting element 20 is , The second surface 22 is shown facing up.
The translucent member 30 does not cover the entire side surface 23 of the light emitting element 20, but partially covers the side surface 23. Therefore, specifically, the side surface 23 of the light emitting element 20 is exposed from the translucent member 30 in the vicinity of the corners 241, 242, 243, 244 on the second surface 22 side of the light emitting element 20. .. In addition, the side of the light emitting element 20 that extends in the z direction through the corners 241, 242, 243, 244 (hereinafter referred to as “third side 231, 232, 233, 234”) is also near the corner. It is exposed from the transparent member 30. (See FIGS. 3 and 2B). The portion of the side surface 23 exposed from the translucent member 30 (exposed portion of the side surface 23) is covered with the covering member 40 described below, and thus is not exposed to the outer surface of the light emitting device 10.

Referring to FIGS. 2A and 2B again, the covering member 40 covers the outer surface 33 of the translucent member 30 and the exposed portion of the side surface 23 of the light emitting element 20 (FIG. 3 ). The covering member 40 is formed of a material that satisfies a predetermined relationship with the translucent member 30 and the light emitting element 20 in terms of the magnitude of the coefficient of thermal expansion. Specifically, the thermal expansion coefficient difference between the translucent member 30 and the light emitting element 20 (this is referred to as “first thermal expansion coefficient difference ΔT ₃₀ ”), and the thermal expansion coefficient between the covering member 40 and the light emitting element 20. The material of the covering member 40 is selected such that ΔT ₄₀ <ΔT ₃₀ when the coefficient difference (which is referred to as “second thermal expansion coefficient difference ΔT ₄₀ ”) is compared. In other words, the material of the covering member 40 is selected so that the coefficient of thermal expansion of the covering member is lower than that of the translucent member. This can prevent the translucent member 30 from peeling off from the light emitting element 20. The mechanism capable of suppressing peeling of the translucent member 30 is considered to be as follows.

The reason why the translucent member 30 is peeled off from the light emitting element 20 is mainly due to heat generation when the light emitting element 20 is turned on. When the light emitting element 20 is a semiconductor light emitting element and the light transmissive member 30 is a resin material, the coefficient of thermal expansion of the light transmissive member 30 (eg, linear expansion coefficient, Young's modulus, etc.) is the same as that of the light emitting element 20. 10 times more than the rate. Therefore, when the light emitting element 20 is turned on, tensile stress is applied to the interface between the light emitting element 20 and the transparent member 30 due to the difference between the thermal expansion amount of the light emitting element 20 and the thermal expansion amount of the transparent member 30. appear. This stress is released when the light emitting element 20 is turned off. That is, when the light emitting element 20 is repeatedly turned on and off, a tensile stress is generated at the interface each time the light is turned on, so that the adhesive force at the interface between the light emitting element 20 and the translucent member 30 is weakened, and finally, The translucent member 30 is separated from the light emitting element 20.

As described above, the light transmissive member 30 allows the light reaching the side surface 23 of the light emitting element 20 to pass through the light transmissive member 30 before the light is reflected by the side surface 23 and attenuated in the light emitting element 20. It is a member for taking out to the outside of. Therefore, when the translucent member 30 is separated from the light emitting element 20, the optical characteristics at the interface between the light emitting element 20 and the translucent member 30 change. That is, a part of the light reaching the side surface 23 of the light emitting element 20 may be reflected by the side surface 23 without being emitted to the translucent member 30. As a result, the amount of light extracted through the translucent member 30 after the peeling of the translucent member 30 may be smaller than that before the exfoliation of the translucent member 30. As a result, the light extraction efficiency of the light emitting device 10 may decrease, and the light distribution characteristics of the light emitting device 10 may change. Therefore, in the light emitting device of the embodiment of the present invention, by using the translucent member 30 and suppressing the translucent member 30 from peeling from the light emitting element 20, the luminous efficiency is improved even after long-term use. An object of the present invention is to provide a highly reliable light emitting device 10 whose light distribution characteristics do not easily change and whose quality is constant.

When the peeled state of the translucent member 30 is observed, it tends to occur starting from the corners 241, 242, 243, 244 (see FIG. 2B and FIG. 3) on the second surface 22 side of the light emitting element 20. I understood it. It is considered that this is because the tensile stress generated at the interface between the light emitting element 20 and the translucent member 30 concentrates at the corners. Particularly, since the semiconductor layered body 28 is formed, heat is easily generated on the second surface 22 side of the light emitting element 20, and among the corner portions of the light emitting element 20, the corner portion on the second surface 22 side. It is considered that peeling is likely to occur at 241, 242, 243, and 244. When the light-transmissive member 30 is not peeled off at the corners 241, 242, 243, 244 on the second surface 22 side of the light-emitting element 20, the light-transmissive member 30 is also formed on the side surface 23 of the light-emitting element 20. It was not peeled off. That is, if the peeling of the transparent member 30 at the corners 241, 242, 243, 244 on the second surface 22 side of the light emitting element 20 can be suppressed, the peeling of the transparent member 30 can be effectively suppressed.

Therefore, in the embodiment of the present invention, as shown in FIGS. 1A, 1B, and 3, most of the side surface 23 of the light emitting element 20 is covered with the translucent member 30 to improve the light extraction efficiency. With the member (covering member 40) which is improved, the corners 241, 242, 243, 244 on the second surface 22 side of the light emitting element 20 are not easily peeled off from the light emitting element 20 (instead of being covered with the translucent member 30). By covering, the peeling of the translucent member 30 that covers the side surface 23 is suppressed. As described above, the cause of the peeling is a large difference in the coefficient of thermal expansion between the light emitting element 20 and the member covering the light emitting element 20. Therefore, “the first coefficient of thermal expansion difference ΔT ₃₀ ”, which is the difference between the coefficient of thermal expansion of the light emitting element 20 and the coefficient of thermal expansion of the translucent member 30, and the coefficient of thermal expansion of the light emitting element 20 and the coefficient of thermal expansion of the light emitting element 20. The second thermal expansion coefficient difference ΔT ₄₀ <when compared with “the second thermal expansion coefficient difference ΔT ₄₀ ”, which is the difference from the thermal expansion coefficient of the covering member 40 that covers the corner portion of the second surface 22 side. The first thermal expansion coefficient difference ΔT ₃₀ is set. That is, when the coefficient of thermal expansion of the transparent member 30 and the coefficient of thermal expansion of the covering member 40 are high, the coefficient of thermal expansion of the covering member 40 is set to the coefficient of thermal expansion of the transparent member 30. Lower. Thus, when the corners 241, 242, 243, and 244 on the second surface 22 side of the light emitting element 20 are covered with the light transmissive member 30, the probability that the light transmissive member 30 is peeled off is higher than the probability that the light transmissive member 30 is peeled. The probability that the covering member 40 will peel off when the covering members 242, 243, and 244 are covered with the covering member 40 is low. Therefore, it is possible to reduce the probability that the translucent member 30 covering the side surface 23 of the light emitting element 20 is peeled off.

Regarding the coefficient of thermal expansion of each member, the coefficient of thermal expansion of the light emitting element 20 is, for example, 7 to 10 ppm/°C. When a resin material is used as the base material, the coefficient of thermal expansion of the translucent member 30 is, for example, 200 to 300 ppm/° C. under the temperature condition of the glass transition point (Tg) or higher. When a resin material is used as the base material, the thermal expansion coefficient of the covering member 40 is, for example, 45 to 100 ppm/° C. under the temperature condition of the glass transition point (Tg) or higher.
As a specific example, assuming that the thermal expansion coefficient of each member is 7 ppm/° C. for the light emitting element 20, 200 ppm/° C. for the translucent member 30, and 45 ppm/° C. for the coating member 40, the first thermal expansion coefficient difference ΔT ₃₀ =(200−7)=193 ppm/° C., “the second thermal expansion coefficient difference ΔT ₄₀ =(45−7)=38 ppm/° C. Therefore, the second thermal expansion coefficient difference ΔT ₄₀ <first The thermal expansion coefficient difference ΔT ₃₀ is satisfied.

In the present specification, the “coefficient of thermal expansion of the light emitting element 20” means the coefficient of thermal expansion of the entire light emitting element 20. For example, as shown in FIGS. 2A and 2B, when the light emitting element 20 includes a plurality of materials such as the translucent substrate 27 and the semiconductor laminated body 28, the coefficient of thermal expansion as a whole is determined. means.

As shown in FIG. 3, when the corners 241, 242, 243, 244 of the light emitting element 20 on the second surface 22 side are exposed from the translucent member 30, light emission near the corners 241, 242, 243, 244. The side surface 23 of the element 20 is also exposed from the translucent member 30. Light reaching the exposed portion of the side surface 23 which is not in contact with the transparent member 30 cannot be extracted from the light emitting device 10 through the transparent member 30. Therefore, from the viewpoint of the light extraction efficiency of the light emitting device 10, it is preferable that the area of the exposed side surface 23 is small. On the other hand, since the exposed portion of the side surface 23 is covered with the covering member 40, the area of the exposed portion is preferably large from the viewpoint of preventing the translucent member 30 from peeling off. Therefore, it is possible to consider various variations in the arrangement and form of the exposed portion depending on the purpose.

As shown in FIG. 3, variations will be described by taking as an example the case where the light emitting element 20 has a substantially rectangular parallelepiped shape having four corner portions 241, 242, 243, 244 on the second surface 22 side. In the example of FIG. 3, the semiconductor stacked body 28 of the light emitting device 20 includes three semiconductor layers of a first conductive type semiconductor layer 281, a light emitting layer 282, and a second conductive type semiconductor layer 283. Of the three semiconductor layers 281, 282, 283 exposed on the side surface of the semiconductor stacked body 28, the first conductivity type semiconductor layer 281 and the light emitting layer 282 are all covered with the light transmissive member 30, and the second semiconductor layer 283 is covered. Only a part is exposed from the translucent member 30.

In the first example of the variation, only one corner (for example, the corner 244 in FIG. 3) is exposed from the translucent member 30, and the remaining three corners 241, 242, and 243 are translucent. It can be covered with 30. As a result, the side surface 23 of the light emitting element 20 can be widely covered up to the corners 241, 242, 243 with the translucent member 30, so that the light extraction efficiency is high. As shown in FIG. 2B, since the corner portion 244 exposed from the translucent member 30 is covered with the covering member 40, the translucent member 30 is separated from the light emitting element 20 in the vicinity of the corner portion 244. Can be suppressed.

In the second example of the variation, two diagonally located corners (eg, corners 241 and 243 in FIG. 3) are exposed from the translucent member 30, and the remaining two corners 242 and 244 are exposed. It can be covered with the transparent member 30. As a result, the side surface 23 of the light emitting element 20 can be covered with the translucent member 30 up to the corners 242 and 244, so that light extraction efficiency is good. The corners 241 and 243 exposed from the translucent member 30 are covered with the covering member 40, as shown in FIG. 2B, so that the translucency from the light emitting element 20 is in the vicinity of the two corners 241 and 243. It is possible to prevent the member 30 from peeling off. Since the stress generated at the interface between the light emitting element 20 and the covering member 40 is relaxed in the two diagonally arranged corners 241, 243, the corners 242, 244 arranged between the corners 241 and 243 are relaxed. However, the effect of alleviating the stress generated at the interface between the light emitting element 20 and the translucent member 30 can be expected.

In the third example of the variation, two adjacent corner portions (for example, the corner portions 243 and 244 in FIG. 3) are exposed from the light transmissive member 30, and the remaining two corner portions 241 and 242 are light transmissive. It can be covered with the member 30. Accordingly, the side surface 23 of the light emitting element 20 can be covered with the translucent member 30 up to the corners 241 and 242, so that the light extraction efficiency is good. Since the corners 243 and 244 exposed from the translucent member 30 are covered with the covering member 40 as shown in FIG. 2B, the translucency from the light emitting element 20 in the vicinity of the two corners 243 and 244. It is possible to prevent the member 30 from peeling off. At this time, the side 223 sandwiched between the two corners 243 and 244 may also be exposed from the translucent member 30 and covered with the covering member 40, so that the peeling suppression effect can be further enhanced. it can.

In the fourth example of the variation, three corners (for example, the corners 241, 242, and 243 in FIG. 3) are exposed from the transparent member 30, and the remaining one corner 244 is exposed. Can be covered with. As a result, the side surface 23 of the light emitting element 20 can be widely covered up to the corner portion 244 with the translucent member 30, so that the light extraction efficiency is good. Since the corners 241, 242, 243 exposed from the translucent member 30 are covered with the covering member 40 as shown in FIG. 2B, the corners 241, 242, 243 are transparent to the light emitting element 20 near the corners 241, 242, 243. The effect of suppressing peeling of the optical member 30 is high.

In the fifth example of the variation, all four corners (corners 241, 242, 243, 244 in FIG. 3) can be exposed from the translucent member 30. Since the corners 241, 242, 243, 244 exposed from the translucent member 30 are covered with the covering member 40 as shown in FIG. 2B, light is emitted near the corners 241, 242, 243, 244. The effect of suppressing peeling of the translucent member 30 from the element 20 is particularly high.

With reference to FIG. 3, the light-transmitting member 20 in which all four corners 241, 242, 243, and 244 are exposed from the light-transmitting member 30 (that is, a fifth example of the variation) is used as an example. The form of the light emitting element 20 covered with 30 will be described in detail. In FIG. 3, the four sides where the first surface 21 and the side surface 23 of the light emitting element 20 contact each other are referred to as “first sides 211, 212, 213, and 214 ”, and the second surface 22 and the side surface 23 are referred to. The four sides that are in contact with each other are referred to as "second sides 221, 222, 223, 224", and the four sides that are in contact with two adjacent side surfaces 23 are referred to as "third sides 231, 232, 233, 234".

The first sides 211, 212, 213, 214 surrounding the first surface 21 of the light emitting element 20 are covered with the translucent member 30 over their entire length. The third sides 231, 232, 233, 234 extending from the first surface 21 to the second surface 22 are in the vicinity of the second surface 22 (that is, the corners 241, 242, 243 on the second surface 22 side). Except for the vicinity of 244), most of them are covered with the translucent member 30. The second sides 221, 222, 223, 224 surrounding the second surface 22 of the light emitting element 20 are the portions excluding the corners 241, 242, 243, 244 on the second surface 22 side (in FIG. The vicinity of the midpoint of the side) is covered with the transparent member 30, and the other portions are exposed from the transparent member 30. By covering the light emitting element 20 with the light transmissive member 30 in this manner, most of the side surface 23 of the light emitting element 20 is covered with the light transmissive member 30, and the corner of the light emitting element 20 on the second surface 22 side. The parts 241, 242, 243, 244 are exposed.

As described above, FIG. 3 shows the case where the corners 241, 242, 243, 244 of the light emitting element 20 on the second surface 22 side are all exposed from the translucent member 30 (fifth example of variation). It is shown. Therefore, when a part of the corner is covered with the translucent member 30 (first to fourth examples of variations), the second side 221, 222, 223, 224, and the third side 231. As for 232, 233, and 234, a larger portion is covered with the translucent member 30. For example, when the corner portion 244 is covered with the translucent member 30, the end portions on the corner portion 244 side of the second sides 223 and 224 extending from the corner portion 244 are covered with the translucent member 30. Further, the third side 234 extending from the corner 244 is covered with the translucent member 30 over the entire length thereof.

Referring again to FIG. 2A, the translucent member 30 covering the side surface 23 of the light emitting element 20 extends beyond the first side (reference numeral 222, 224 of FIG. 2A) of the light emitting element 20. The first surface 21 may be partially covered, or the entire surface of the first surface 21 may be covered. The translucent member 30 can protect the first surface 21 of the light emitting element 20. When the wavelength conversion member 50 is provided on the first surface 21 side of the light emitting element 20, the translucent member 30 is provided between the first surface 21 of the light emitting element 20 and the wavelength conversion member 50. , And can function as an adhesive member that adheres the first surface 21 and the wavelength conversion member 50.

In FIG. 3, the translucent member 30 covering the side surface 23 of the light emitting element 20 is formed so as to partially reach the second sides 221, 222, 223, and 224, but not to exceed the second sides. Is preferred. That is, as shown in FIG. 3, the upper edge of the translucent member 30 is located below the second sides 221, 222, 223, 224 in the vicinity of the corners 241, 242, 243, 244, Otherwise, it coincides with the second side. The translucent member 30 having such a shape uses a liquid resin material as a raw material of the translucent member 30, and utilizes that the liquid resin material wets and spreads on the side surface 23 of the light emitting element 20 due to surface tension. Therefore, it can be easily formed. Furthermore, by providing a step at the portion where the second surface 22 and the side surface 23 of the light emitting element 20 intersect, it is possible to prevent the liquid resin material from spreading over the second surface 22 beyond the step. it can. Such a step is formed by removing, for example, a part of the semiconductor stacked body 28 of the light emitting element 20, and more preferably, a part of the second semiconductor layer 283 near the second surface 22 of the light emitting element 20. , Can be provided.
It is preferable that the translucent member 30 covers the light emitting layer 282 exposed on the side surface 23 of the light emitting element 20 as wide as possible, and particularly covers all of the light emitting layer 282. Thereby, the light emitted from the light emitting layer 282 can be efficiently extracted to the outside of the light emitting element 20 through the translucent member 30.

In addition, it is not excluded that the upper edge portion of the translucent member 30 extends beyond the second sides 221, 222, 223 and 224 of the light emitting element 20. That is, the upper edge of the translucent member 30 may exceed the second sides 221, 222, 223, 224 of the light emitting element 20, and the translucent member 30 may partially cover the second surface 22. .. However, if the second surface 22 is widely covered with the translucent member 30, the problem of peeling at the interface between the second surface 22 and the translucent member 30 may become significant.

As shown in FIGS. 2A, 2</b>B, and 3, the outer surface 33 of the translucent member 30 faces outward from the second surface 22 side of the light emitting element 20 toward the first surface 21 side. Inclined is preferred. That is, in the cross-sectional views as shown in FIGS. 2A and 2B, the left and right outer surfaces 33 of the translucent member 30 expand toward the first surface (light emitting surface) 11 of the light emitting device 10. Is preferred. The light emitted from the side surface 23 of the light emitting element 20 and propagating in the translucent member 30 reaches the inclined outer surface 33. Here, when the light is reflected by the outer surface 33, the light can be directed toward the first surface 11 of the light emitting device 10. Thereby, the light extraction efficiency of the light emitting device 10 can be improved.

In a cross section parallel to one side surface 23 of the light emitting element 20 (a cross section taken along the line AA in FIG. 1, that is, FIG. 2A), another side surface 23 orthogonal to the one side surface 23 and another It is preferable that the angle formed by the outer surface 33 of the translucent member 30 that covers the side surface 23 of the above (referred to as “inclination angle θ ₁ ”) is in an appropriate range. Specifically, the inclination angle θ ₁ is preferably 40° to 60°, and can be set to 45°, for example. If the inclination angle θ ₁ is large, the outer shape of the first surface 31 of the translucent member 30 (depicted as a substantially circular shape in FIG. 1) becomes large, and the light extraction efficiency is improved. On the other hand, when the inclination angle θ ₁ is small, the outer shape of the first surface 31 is small, and thus the size of one side of the light emitting device 10 in a top view can be reduced (that is, the light emitting device 10 can be downsized). Considering both the light extraction efficiency and the miniaturization of the light emitting device 10, the inclination angle θ ₁ =45° is optimal.

In a cross section taken along a diagonal line of the light emitting element 20 in plan view (a cross section taken along line BB in FIG. 1, that is, FIG. 2B), a third side of the light emitting element 20 (reference numeral of FIG. 2B) 231, 233) and the outer surface 33 of the translucent member 30 that covers the third side thereof (this is referred to as “inclination angle θ ₂ ”) is smaller than the inclination angle θ ₁ . That is, as shown in FIGS. 2A and 2B, the inclination angle θ ₂ <the inclination angle θ ₁ .

The outer surface 33 of the translucent member 30 is provided with a ridge line starting from a point where the outer surface 33 contacts the third sides 231, 232, 233, 234 (see FIG. 3) of the light emitting element 20. May be. However, when the outer surface 33 has a ridge line, the light incident on the translucent member 30 from the side surface 23 of the light emitting element 20 causes the interface between the outer surface 33 of the translucent member 30 and the covering member 40 (FIG. 2A, When reflected in (b), light may be repeatedly reflected between surfaces located on both sides of the ridge (that is, two surfaces forming the ridge) near the ridge. .. Light may be gradually absorbed and weakened in intensity during repeated reflection, which may lead to a reduction in light extraction efficiency of the light emitting device 10. In order to improve the light extraction efficiency, it is preferable that the outer surface of the translucent member 30 has no ridge line, that is, the outer surface 33 of the translucent member 30 is formed of a smoothly continuous curved surface. Thereby, multiple reflection inside the translucent member 30 can be reduced and the light extraction efficiency of the light emitting device 10 can be improved.

The outer surface 33 of the translucent member 30 may be linear in the sectional views shown in FIGS. 2A and 2B, but may be curved. Here, the “curved shape” may be a curve that is convex outward (on the covering member 40 side) or a curve that is convex inward (on the light emitting element 20 side). From the viewpoint of light extraction efficiency, the outer surface 33 is preferably a curve that is convex outward.
The outward curved convex outer surface 33 in the sectional view has a dome shape as shown in FIG. 3 in the perspective view. Further, the curved outer surface 33 that is convex inward in the cross-sectional view has a trumpet shape (flare type) as shown in FIG.

When the light emitting element 20 includes the transparent substrate 27 and the semiconductor laminated body 28, as shown in FIG. 2, the transparent substrate 27 is arranged on the first surface 21 side of the light emitting element 20, and the semiconductor laminated body is arranged. 28 can be arranged on the second surface 22 side. When the light emitting element 20 is turned on, heat is generated in the light emitting layer (reference numeral 282 in FIG. 3) included in the semiconductor stacked body 28. Therefore, the light transmissive member 30 is separated from the light emitting element 20 in the vicinity of the semiconductor stacked body 28 side. It's easy to do. As shown in FIG. 2B, on the second surface 22 side of the light emitting element 20, the corners of the light emitting element 20 (reference numerals 241 and 243 in FIG. 2B) are exposed from the translucent member 30. And is covered with the covering member 40. As a result, peeling of the translucent member 30 from the light emitting element 20 is suppressed on the second surface 22 side of the light emitting element 20. Therefore, by disposing the semiconductor laminated body 28, which is a source of heat generation that causes peeling, on the second surface 22 side of the light emitting element 20, it is possible to effectively suppress peeling of the translucent member 30. it can.

FIG. 4 shows the light emitting device 10 as viewed from the second surface 12 side. The pair of electrodes 251 and 252 of the light emitting element 20 are exposed from the covering member 40 and are exposed to the second surface (lower surface) 12 of the light emitting device 10. Thereby, the external electrodes provided on the substrate or the like on which the light emitting element 20 is mounted can be connected to the electrodes 251 and 252 of the light emitting element 20. In addition, in the light emitting element 20, it is preferable that the portion of the second surface 22 other than the portion where the electrodes 251 and 252 are provided is covered with the covering member 40 in order to protect the light emitting element 20 from the external environment.

When covering the second surface 22 of the light emitting element 20 with the covering member 40, the electrodes 251 and 252 formed on the second surface 22 of the light emitting element 20 are exposed on the surface (second surface 12) of the light emitting device 10. To do so. For example, the side surfaces of the electrodes 251 and 252 (reference numerals 251c and 252c in FIG. 3) may be covered with the covering member 40, but the surfaces 251s and 252s of the electrodes 251 and 252 are covered so as not to be covered with the covering member 40. The thickness of the member 40 is adjusted. The surfaces 251s and 252s of the electrodes may be projected from the covering member 40 or may be substantially flush with each other (see FIG. 2A).

Referring to FIGS. 2A and 2B again, as described above, the light emitting device 10 may include the wavelength conversion member 50 on the first surface 11 side. The wavelength conversion member 50 is a member for converting a part of transmitted light into another wavelength. The wavelength conversion member 50 contains a phosphor that is excited by the transmitted light. Since the light emitting device 10 includes the wavelength conversion member 50, it is possible to obtain the light emitting device 10 having an emission color different from the emission color of the light emitting element 20. For example, the light emitting device 10 that emits white light can be obtained by combining the light emitting element 20 that emits blue light and the wavelength conversion member 50 that absorbs blue light and emits yellow fluorescence.

The wavelength conversion member 50 is preferably provided so as to cover the first surface 21 of the light emitting element 20 and the first surface 31 of the translucent member 30. The light generated by the light emitting element 20 is directly extracted from the first surface 21 of the light emitting element 20, or is emitted from the side surface 23 of the light emitting element 20 and passes through the transparent member 30 to reach the first side of the transparent member 30. It is indirectly taken out from the surface 31 of No. 1. Therefore, by arranging the wavelength conversion member 50 so as to cover the first surface 21 of the light emitting element 20 and the first surface 31 of the translucent member 30, substantially all of the light generated by the light emitting element 20 can be obtained. Can be passed through the wavelength conversion member 50. That is, since there is substantially no light that does not pass through the wavelength conversion member 50, it is possible to suppress color unevenness in the light emitted from the light emitting device 10.

<First manufacturing method>
Next, with reference to FIG. 5, a first manufacturing method of the light emitting device 10 according to the present embodiment will be described.

Step 1-1. Fixing Light Emitting Element 20 The light emitting element 20 is arranged on the wavelength conversion member 50 (FIG. 5A). At this time, the first surface 21 of the light emitting element 20 is arranged so as to face the second surface 52 of the wavelength conversion member 50. The light emitting element 20 can be fixed to the wavelength conversion member 50 with a translucent adhesive or the like. Instead of using the adhesive, the light emitting element 20 may be fixed to the wavelength conversion member 50 by the translucent member 30 formed later. Further, when the wavelength conversion member 50 itself has adhesiveness (when it is in a semi-cured state or the like), it may be fixed without using an adhesive.

Step 1-2. Formation of Translucent Member 30 The translucent member 30 is formed so as to cover a part of the side surface 23 of the light emitting element 20 and a region of the second surface 52 of the wavelength conversion member 50 in the vicinity of the light emitting element 20. (FIG.5(b)). When the translucent member 30 is formed of a translucent resin material, the liquid resin material 30L, which is a raw material of the translucent member 30, is used for the first side of the light emitting element 20 (see FIG. 5(b) is applied along the boundaries between the reference numerals 212 and 214 and the wavelength conversion member 50. The liquid resin material 30L spreads over the wavelength conversion member 50 and crawls the side surface 23 of the light emitting element 20 due to surface tension. After that, the liquid resin material 30L is cured by heating or the like to obtain the translucent member 30.

The distance that the liquid resin material 30L crawls the light emitting element 20 can be controlled by adjusting the viscosity and the coating amount of the liquid resin material 30L. For example, in the translucent member 30 shown in FIG. 3, the liquid resin material 30L crawls up the side surface 23 of the light emitting element 20 and comes into contact with part of the second sides 221, 222, 223, 224. However, on the third sides 231, 232, 233, 234, the liquid resin material crawls up partway, but does not reach the corners 241, 242, 243, 244 of the light emitting element 20. Exposing the corner portions 241, 242, 243, 244 of the light emitting element 20 from the translucent member 30 by adjusting the viscosity and the coating amount of the liquid resin material 30L so that the liquid resin material 30L has a form as shown in FIG. You can The viscosity of the liquid resin material 30L can be adjusted by adding a filler or the like.

When the translucent member 30 is formed from the liquid resin material 30L, the outer surface 33 of the translucent member 30 is outwardly directed in the Z direction (that is, away from the side surface 23 of the light emitting element 20) due to surface tension. It can be tilted (Fig. 5(b)).

Step 1-3. Formation of Covering Member 40 Outer surface 33 of translucent member 30 and a portion of second surface 52 of wavelength conversion member 50 that is not covered with translucent member 30 (that is, second surface 52 is exposed). The portion) that is present is covered with the covering member 40. Further, a portion of the second surface 22 of the light emitting element 20 that is not covered with the electrodes 251 and 252 (that is, an exposed portion of the second surface 22) may be covered with the covering member 40. At this time, the thickness (dimension in the −Z direction) of the covering member 40 is adjusted so that part of the electrodes 251 and 252 (for example, the surfaces 251s and 252s of the electrodes 251 and 252) are exposed from the covering member 40. Is preferred. That is, the height of the second surface 42 of the covering member 40 may be equal to or less than the height of the surfaces 251s and 252s of the electrodes 251, 252 when the second surface 52 of the wavelength conversion member 50 is used as a reference.

When the covering member 40 is formed of a resin material, for example, a mold surrounding the light emitting element 20 and the translucent member 30 is provided, and the liquid resin material 40L which is a raw material of the covering member 40 is placed inside the mold. Pour. At this time, the wavelength conversion member 50 can be used as the bottom of the mold by fitting the mold around the outer periphery of the wavelength conversion member 50 (see FIG. 5C). After that, the liquid resin material 40L is cured by heating or the like to obtain the covering member 40. By removing the mold, the light emitting device 10 as shown in FIGS. 1, 2 and 4 can be obtained. The covering member 40 may be formed by spray coating, compression molding, or various methods. Further, after forming the covering member so as to fill the electrodes 251, 252, only the covering member 40, or the covering member 40 and a part of the electrodes 251, 252 may be removed to expose the electrodes 251, 252.

<Second manufacturing method>
A second manufacturing method of the light emitting device 10 according to the present embodiment will be described with reference to FIGS. 6 to 10. In the second manufacturing method, a plurality of light emitting devices 10 can be manufactured at the same time.

Step 2-1. Fixing Light-Emitting Element 20 The light-emitting element 20 is arranged on the second surface 520 of the wavelength conversion sheet 500 (FIGS. 6A and 9A). The wavelength conversion sheet 500 becomes the wavelength conversion member 50 after being divided into individual light emitting devices 10. At this time, using the relatively large wavelength conversion sheet 500, the plurality of light emitting elements 20 are arranged on one wavelength conversion sheet 500. Adjacent light emitting elements 20 are arranged with a predetermined interval. If the space between the adjacent light emitting elements 20 is too wide, the number of light emitting devices 10 that can be formed at the same time decreases, and the efficiency of mass production of the light emitting devices 10 deteriorates. Therefore, the light emitting elements 20 are arranged at appropriate intervals. Is desirable. The light emitting element 20 has steps 1-1. of the first manufacturing method. The wavelength conversion sheet 500 is fixed at a predetermined position by a fixing method similar to the fixing method described in (1).

Step 2-2. Formation of translucent member 30 Step 1-2 of the first manufacturing method 1-2. Similarly, the translucent member 30 is formed around each light emitting element 20 (FIGS. 6B and 9B ). The translucent member 30 formed around a certain light emitting element 20 and the translucent member 30 formed around the light emitting element 20 arranged adjacent to the light emitting element 20 do not come into contact with each other. The optical member 30 is formed.

Step 2-3. Formation of coating member 400 Steps of first manufacturing method 1-3. Similarly, the outer surface 33 of the translucent member 30 and the second surface 520 of the wavelength conversion sheet 500 are covered with the covering member 400 (FIGS. 7A and 9C). The covering member 400 becomes the covering member 40 after being divided into individual light emitting devices 10. Step 2-3. In steps 1-3. Unlike the above, the thickness (dimension in the −z direction) of the covering member 400 is adjusted so as to cover the surfaces 251s and 252s of the electrodes 251 and 252 of the light emitting element 20. At this time, the plurality of translucent members 30 provided around the plurality of light emitting elements 20 arranged on the wavelength conversion sheet 500 are covered with one continuous covering member 400.
After that, the thickness of the covering member 400 is reduced by a known processing method so that the electrodes 251 and 252 of the light emitting element 20 are exposed (FIGS. 7B and 10A ).

Step 2-4. Dividing into individual pieces of the light emitting device 10 A covering member along a broken line X ₁ , a broken line X ₂ , a broken line X ₃ and a broken line X ₄ (FIGS. 7B and 10A) passing through the middles of the adjacent light emitting elements 20. 400 and the wavelength conversion sheet 500 are cut with a dicer or the like. As a result, the individual light emitting devices 10 are separated (FIGS. 8 and 10(b)). In this way, it is possible to simultaneously manufacture a plurality of light emitting devices 10 each including one light emitting element 20.

In the individualized light emitting device 10, when the translucent member 30 is exposed on the side surface 13 of the light emitting device 10 (side surface 40c of the covering member 40), the light emitted from the light emitting element 20 passes through the translucent member 30. And laterally leaks from the side surface 13 of the light emitting device 10. Therefore, it is preferable to adjust the distance between the adjacent light emitting elements 20 and the viscosity of the transparent member 30 so that the transparent member 30 is not exposed from the side surface 13 of the light emitting device 10.

<Third manufacturing method>
A third manufacturing method of the light emitting device 10 according to the present embodiment will be described with reference to FIGS. 11 to 12. In the third manufacturing method, a plurality of light emitting devices 10 can be manufactured at the same time. Note that description of steps similar to those of the second manufacturing method is omitted.

Step 3-1. Arrangement of Translucent Member 30 On the second surface 520 of the wavelength conversion sheet 500, the liquid resin material 300 for forming the translucent member 30 is applied in the form of a plurality of separated islands (see FIG. ), 12(a)). At this time, using a relatively large wavelength conversion sheet 500, a plurality of island-shaped liquid resin materials 300 are arranged on one wavelength conversion sheet 500. Each liquid resin material 300 provided in an island shape can have any shape in plan view, and examples thereof include a circle, an ellipse, a square, and a rectangle. Note that if the spacing between the adjacent island-shaped liquid resin materials 300 is too wide, the number of light emitting devices 10 that can be formed at the same time decreases, and the efficiency of mass production of the light emitting devices 10 deteriorates. It is desirable to arrange them at intervals.

Step 3-2. Fixing Light-Emitting Element 20 and Curing Liquid Resin Material 300 As shown in FIGS. 11B and 12B, the light-emitting element 20 is arranged on each island-shaped liquid resin material 300. By only disposing the light emitting element 20 on the island-shaped liquid resin material 300, or by pressing the light emitting element 20 after disposing the liquid resin material 300, the liquid resin material 300 climbs to the side surface 23 of the light emitting element 20 due to surface tension. The outer surface 303 of the liquid resin material 300 (the outer surface 33 of the translucent member 30 later) has a shape spreading downward. Then, the liquid resin material 300 is cured to form the translucent member 30.
The shape of the liquid resin material 300 in plan view is deformed by disposing or pressing the light emitting element 20, and the first surface 31 of the translucent member 30 included in the light emitting device 10 which is the final product (see FIGS. 1 and 2). The shape is almost the same as the outer shape.

In this manufacturing method, the liquid resin material 300 exists in a film form between the wavelength conversion sheet 500 and the light emitting element 20. The film-shaped translucent member 30t formed by curing the film-shaped liquid resin material 300 can also function as an adhesive between the wavelength conversion sheet 500 and the light emitting element 20. The thickness of the film-shaped translucent member 30t is preferably determined in consideration of adhesiveness and heat dissipation of the light emitting device 10. Specifically, the thickness of the film-shaped translucent member 30t is set so that the heat generated from the wavelength conversion member 500 can be efficiently conducted to the light emitting element 20 side when the light emitting device 10 emits light. Can be, for example, 2 to 30 μm, preferably 4 to 20 μm, and most preferably about 5 to 10 μm.

Then, steps 2-3 of the second manufacturing method. The covering member 400 is formed in the same manner as in step 2-4. Similarly, the light emitting device 10 is divided into individual pieces. Thereby, a plurality of light emitting devices 10 each including one light emitting element 20 can be simultaneously manufactured.

As described above, according to this manufacturing method, the light emitting element 20 is disposed on the wavelength conversion sheet 500 on which the liquid resin material 300 is applied in an island shape, whereby the light emitting element 20 is adhered and the translucent member 30 is formed. The formation can be done simultaneously. Thereby, mass productivity can be improved. ..

<Fourth manufacturing method>
A fourth manufacturing method of the light emitting device 10 according to the present embodiment will be described with reference to FIGS. 13 to 14. In the fourth manufacturing method, a plurality of light emitting devices 10 can be manufactured at the same time.

Step 4-1. Fixing Light-Emitting Element 20 The light-emitting element 20 is placed on the upper surface 60a of the support member 60 made of a heat-resistant sheet or the like (FIG. 13A). At this time, a plurality of light emitting elements 20 are arranged on one support member 60 using a relatively large support member 60. Similar to step 2-1 of the second manufacturing method, the adjacent light emitting elements 20 are arranged with a predetermined space. The light emitting element 20 has steps 1-1. of the first manufacturing method. The supporting member 60 is fixed at a predetermined position by the fixing method similar to the fixing method described above.

Step 4-2. Formation of translucent member 30 Step 1-2 of the first manufacturing method 1-2. Similarly, the translucent member 30 is formed around each light emitting element 20 (FIG. 13B). The translucent member 30 formed around a certain light emitting element 20 and the translucent member 30 formed around the light emitting element 20 arranged adjacent to the light emitting element 20 do not come into contact with each other. The optical member 30 is formed.

Step 4-3. Formation of coating member 400 Steps of first manufacturing method 1-3. The outer surface 33 of the translucent member 30 and the upper surface 60a of the support member 60 are covered with the covering member 400 in the same manner as in (FIG. 13C). The covering member 400 becomes the covering member 40 after being divided into individual light emitting devices 10. The plurality of translucent members 30 provided around the plurality of light emitting elements 20 arranged on the support member 60 are covered with one continuous covering member 400.

Step 4-4. Formation of Wavelength Conversion Layer 510 The supporting member 60 is removed (peeled) to expose the first surface 21 of the light emitting element 20 and the first surface 400a of the covering member 400 (FIG. 14A). Then, the wavelength conversion layer 510 is formed to cover the first surface 21 of the light emitting element 20 and the first surface 400a of the covering member 400 (hereinafter, referred to as “first surface 21, 400a”). The wavelength conversion layer 510 becomes the wavelength conversion member 50 after being separated into individual light emitting devices 10. As a method of forming the wavelength conversion layer 510, a sheet made of a translucent resin containing a phosphor is adhered to the first surfaces 21 and 400a by a hot melt or an adhesive, and a first surface is formed by an electrophoretic deposition method. 21, a method of impregnating the attached phosphor with a translucent resin after adhering the phosphor to the 400a, potting, transfer molding, compression molding, casting case molding of the translucent resin containing the phosphor, Examples thereof include a method of coating the first surface 21, 400a by a known technique such as a spray method, an electrostatic coating method, or a printing method. Among these methods, the spray method is preferable, and the pulse spray method in which the spray is intermittently injected is particularly preferable.

Step 4-5. Separation of Light Emitting Device 10 Similar to Step 2-4 of the second manufacturing method, the covering member 400 and the wavelength conversion layer 510 are formed along the broken line X ₁ and the broken line X ₂ passing through the middle of the adjacent light emitting elements 20. Is cut with a dicer or the like (FIG. 14B). As a result, the individual light emitting devices 10 are separated (FIG. 14C). In this way, it is possible to simultaneously manufacture a plurality of light emitting devices 10 each including one light emitting element 20.

<Second Embodiment>
As shown in FIG. 15, the light emitting device 15 according to the present embodiment is different from the light emitting device 10 according to the first embodiment in that the side surface 501 b of the wavelength conversion member 501 is covered with the covering member 403. The difference is that the covering member 403 has a two-layer structure. The other points are similar to those of the first embodiment.

The light emitting device 15 according to the present embodiment includes a light emitting element 20, a wavelength conversion member 501 that covers the first surface 21 of the light emitting element 20, and a translucent member 30 provided on the side surface 23 side of the light emitting element 20. , And a covering member 403 that covers the outer surface 33 of the translucent member 30. In the present embodiment, the covering member 403 includes a first covering member 401 that covers the side surface 501b of the wavelength conversion member 501 and a second covering member 402 that covers the outer surface 33 of the translucent member 30.

By covering the side surface 501b of the wavelength conversion member 501 with the covering member 403 (first covering member 401), light emitted from the light emitting element 20 propagates inside the wavelength conversion member 501 and leaks laterally from the side surface 501b. Can be suppressed. Most of the light emitted from the light emitting device 15 is extracted from the first surface (upper surface) 16 that functions as a light emitting surface of the light emitting device 15. That is, since the light from the light emitting device 15 is emitted in substantially the z direction, the directivity of the light of the light emitting device 15 can be enhanced.

Next, a method of manufacturing the light emitting device 15 will be described with reference to FIGS.
Step A. Formation of Wavelength Conversion Member 501 A coating material layer 404 for forming the first coating layer 401 is formed on the first support member 61 made of a heat resistant sheet or the like (FIG. 16A). After that, a plurality of through holes 409 are provided in the coating material layer 404 to obtain a frame member 405 (FIG. 16(b)). The size and shape of the inner surface of the through hole 409 of the frame member 405 when viewed from the z direction are the same as the size and shape of the outer shape of the wavelength conversion member 501 in the plan view of the light emitting device 15 shown in FIG. is there. When forming the through hole 409, the through hole 409 is formed so as to penetrate the coating material layer 404 and not to penetrate the first supporting member 61.

A translucent resin (liquid resin material before curing) 502L containing a phosphor is potted into each through hole 409 (FIG. 16B). Then, the translucent resin 502L is cured by heating to form the phosphor-containing member 502 (FIG. 16C). The “upper part of the phosphor-containing member 502” and the “upper part of the frame member 405” above the Ct-Ct line (broken line) in FIG. 16C are removed by cutting or the like. As a result, a sheet-shaped member including the lower portion of the phosphor-containing member 502 (wavelength conversion member 501) and the lower portion of the frame member 405 (hereinafter referred to as “thin frame member 406”) is formed ( FIG. 16D). The thin frame member 406 will later become the first coating layer 401 shown in FIG. Next, the sheet-shaped member (wavelength conversion member 501 and thin frame member 406) is transferred to the second support member 62 made of a heat-resistant sheet or the like (FIG. 16(e)). The transfer of the sheet-shaped member may be omitted.

Step B. Fixing Light-Emitting Element 20 The light-emitting element 20 is fixed on the exposed surface 501x of each wavelength conversion member 501 (FIG. 17A). The fixing method of the light emitting element 20 is the same as the step 1-1. This is the same as the fixing method described in.

Step C. Formation of translucent member 30 Step 1-2 of the first embodiment. Similarly, the liquid resin material 30L which is a raw material of the translucent member 30 is applied around the light emitting element 20 (FIG. 17B). 30 L of liquid resin materials are hardened by heating etc. and the translucent member 30 is obtained. The applied liquid resin material 30L spreads along the exposed surface 501x of the wavelength conversion member 501, but when it reaches the boundary line between the wavelength conversion member 501 and the thin frame member 406, the liquid resin material 30L is further pinned. It becomes difficult to spread. Therefore, in the light emitting device 15 of the present embodiment, it is easy to control the form of the translucent member 30. As shown in FIG. 15A, the translucent member 30 does not reach the four corner portions 501e (hatched portions) of the wavelength conversion member 501. Therefore, the four corner portions 501e are exposed from the translucent member 30.

Step D. Formation of coating member 407 Step 1-3 of the first embodiment. In the same manner as the above, the outer surface 33 of the translucent member 30, the four corners of the wavelength conversion member 501 (reference numeral 501e in FIG. 15A), and the thin frame member 406 surrounding the wavelength conversion member 501. The second surface 406b is covered with a covering member 407 (FIG. 17C). The covering member 407 becomes the covering member 402 after being divided into individual light emitting devices 15. The plurality of translucent members 30 provided around the plurality of light emitting elements 20 are covered with one continuous covering member 407. As shown in FIG. 15A, the wavelength conversion member 501 is covered with the translucent member 30 except for the four corner portions 501e. Therefore, in the wavelength conversion member 501, only the four corner portions 501e that are not covered with the translucent member 30 are covered with the covering member 407 (FIG. 15C).

Process E. Dividing the light emitting device 15 into individual pieces The covering member 407, the thin frame member 406, and the second supporting member 62 are formed by a dicer or the like along broken lines X ₅ and X ₆ passing through the middles of the adjacent light emitting elements 20. Disconnect. Finally, the second support member 62 is removed (peeled) to obtain the light emitting device 15. The second supporting member 62 may be removed before cutting, and then the covering member 407 and the thin frame member 406 may be cut.

<Third Embodiment>
In this embodiment, the shape of the electrode of the light emitting element included in the light emitting device is different from the shape of the electrodes 251 and 252 of the light emitting element 20 of the first embodiment. The other configuration of the light emitting device is the same as that of the first embodiment.

FIG. 18 is a perspective view of the light emitting device 17 according to the present embodiment. The light emitting element 207 included in the light emitting device 17 includes the semiconductor stacked body 28 and a pair of electrodes 257 and 258. On the second surface (lower surface) 172 of the light emitting device 17, the surfaces 257s and 258s of the pair of electrodes 257 and 258 are exposed from the covering member 40.

In this embodiment, the surface 257s of the first electrode 257 and the surface 258s of the second electrode 258 have different shapes. The surface 257s of the first electrode 257 is a rectangle extending in one direction (y direction). The surface 258s of the second electrode 258 has a comb shape in which a plurality of convex portions 258a and a plurality of concave portions 258b are alternately arranged on the side 258L facing the first electrode 257. The recess 258b is filled with the covering member 40. Thereby, the adhesion between the light emitting element 20 and the covering member 40 can be improved.

The shape of the convex portion 258a and the concave portion 258b can be any shape. For example, in FIG. 18, the shape of the recess 258b is a shape including a strip-shaped portion extending from the side 258L in the x direction and a circular portion provided at the end of the strip-shaped portion. When two or more recesses 258b are formed, the recesses 258b may all have the same shape as shown in FIG. 18, or may have some or all different shapes. When three or more recesses 258b are formed, the intervals between the adjacent recesses 258b may be all equal as shown in FIG. 18, or may be different.

19 is a plan view of the light emitting device 17 in which the covering member 40 illustrated in FIG. 18 is omitted, and FIG. 20 is a perspective view of the light emitting device 17 in which the covering member 40 is omitted. As shown in FIGS. 19 and 20, the light emitting element 207 is on the second surface 207b side, more specifically, on the second semiconductor layer 283 side of the semiconductor laminate 28 of the light emitting element 207 (see FIGS. 20 and 3). ) Can be provided with a reflective film 29. The reflective film 29 can be formed of a metal having a high light reflectance such as Ag or Al, or a material such as a dielectric multilayer film. By providing the reflective film 29, the light directed to the second surface 207b can be reflected in the first surface 207a.
As shown in FIG. 19, in the light emitting element 207, the semiconductor laminated body 28 and the reflective film 29 may not be formed in the corner portion of the translucent substrate 27 because of the manufacturing process. It is desirable that the corners of the translucent substrate 27 on which the reflective film 29 is not formed be covered with the covering member 40, and the light traveling toward the corners of the translucent substrate 27 is transferred between the translucent substrate 27 and the covering member 40. By reflecting at the interface of, the light extraction efficiency of the light emitting device 10 can be improved.

Materials suitable for the constituent members of the light emitting device 10 according to the first to third embodiments will be described below.
(Light emitting element 20, 207)
As the light emitting elements 20 and 207, for example, a semiconductor light emitting element such as a light emitting diode can be used. The semiconductor light emitting device can include a transparent substrate 27 and a semiconductor stacked body 28 formed thereon.

(Translucent substrate 27)
The translucent substrate 27 of the light emitting elements 20 and 207 has, for example, a translucent insulating material such as sapphire (Al ₂ O ₃ ) or spinel (MgA1 ₂ O ₄ ), or light emitted from the semiconductor laminated body 28. A semiconductor material (for example, a nitride-based semiconductor material) that transmits light can be used.

(Semiconductor laminate 28)
The semiconductor stacked body 28 includes a plurality of semiconductor layers. As an example of the semiconductor stacked body 28, three semiconductors of a first conductive type semiconductor layer (for example, n-type semiconductor layer) 281, a light emitting layer (active layer) 282, and a second conductive type semiconductor layer (for example, p-type semiconductor layer) 283 are provided. It can include layers (see Figure 3). The semiconductor layer can be formed of a semiconductor material such as a III-V group compound semiconductor or a II-VI group compound semiconductor. Specifically, nitride-based semiconductor materials such as In _X Al _Y Ga _1-X-Y N (0≦X, 0≦Y, X+Y≦1) (for example, InN, AlN, GaN, InGaN, AlGaN, InGaAlN). Etc.) can be used.

(Electrodes 251, 252, 257, 258)
As the electrodes 251, 252, 257, 258 of the light emitting elements 20, 207, good electric conductors can be used, and metal such as Cu is suitable.

(Translucent member 30)
The translucent member 30 can be formed of a translucent material such as translucent resin or glass. The translucent resin is preferably a thermosetting translucent resin such as a silicone resin, a silicone-modified resin, an epoxy resin, or a phenol resin. Since the translucent member 30 is in contact with the side surface 23 of the light emitting element 20, it is easily affected by the heat generated in the light emitting element 20 during lighting. Since the thermosetting resin has excellent heat resistance, it is suitable for the translucent member 30. The translucent member 30 preferably has a high light transmittance. Therefore, normally, it is preferable that no additive that reflects, absorbs, or scatters light is added to the translucent member 30. However, it may be preferable to add an additive to the translucent member 30 in order to impart desired characteristics. For example, various fillers may be added to adjust the refractive index of the translucent member 30 or to adjust the viscosity of the translucent member (liquid resin material 300) before curing.

In a plan view of the light emitting device 10, the outer shape of the first surface 31 of the translucent member 30 is at least larger than the outer shape of the second surface 22 of the light emitting element 20. The outer shape of the first surface 31 of the translucent member 30 can be various shapes, for example, a circle as shown in FIG. 21A and a square with rounded corners as shown in FIG. 15A. , And oval, square, rectangular, and other shapes.
In particular, as shown in FIG. 21A, the dimensions of the first surface 31 of the transparent member 30 in plan view (from the outer shape of the first surface 21 of the light emitting element 20 to the first surface of the transparent member 30). Regarding the distance to the outer shape of the surface 31), the dimension 30D on the diagonal line of the light emitting element 20 is compared with the dimension 30W on the line perpendicular to the side surface 23 from the center of the side surface 23 of the light emitting element 20. <It is preferable that the dimension is 30 W. In order to satisfy the dimensional conditions, the shape of the first surface 31 of the translucent member 30 is preferably a circle, an ellipse, or a quadrangle with rounded corners.

The outer shape of the first surface 31 of the translucent member 30 may be determined based on other conditions. For example, when the light emitting device 10 is used in combination with an optical lens (secondary lens), it is preferable that the outer shape of the first surface 31 is circular, because the light emitted from the light emitting device 10 is also close to circular. , The optical lens makes it easier to collect light. On the other hand, when miniaturization of the light emitting device 10 is desired, it is preferable that the outer shape of the first surface 31 be a quadrangular shape with rounded corners, and the size 30 W can be reduced, so that the size of the upper surface 11 of the light emitting device 10 is reduced. can do.
Generally, the ratio of the dimension 30D to the dimension 30W is 30D/30W=2/3 to 1/2 in consideration of the ease of focusing by the optical lens and the miniaturization of the light emitting device 10. Is preferred.

Further, as shown in FIGS. 21A and 21B, when the dimension from the first surface 21 to the second surface 22 of the light emitting element 20 is “thickness 20T of the light emitting element 20”, the dimension is 30 W. And the thickness 20T can be approximated by the relationship of tan θ ₁ =30W/20T. Here, for example, when 30W=250 μm and 20T=150 μm, the inclination angle θ ₁ =59°, and the light extraction efficiency can be increased.
As described above, since the inclination angle θ ₁ is preferably 40° to 60°, if the thickness 20T of the light emitting element 20 to be used is determined, the preferable range of 30 W can also be determined.

(Coating members 40, 403)
The covering members 40 and 403 are formed of a material that has a predetermined coefficient of thermal expansion relationship with the translucent member 30 and the light emitting element 20. That is, in the covering members 40 and 403, the difference in thermal expansion coefficient ΔT ₄₀ between the covering members 40 and 403 and the light emitting element 20 is smaller than the difference in thermal expansion coefficient ΔT ₃₀ between the translucent member 30 and the light emitting element 20. Then, the material is selected. For example, when the light emitting element 20 includes the sapphire translucent substrate 27 and the semiconductor laminated body 28 made of a GaN-based semiconductor, the thermal expansion coefficient of the light emitting element 20 is about 5 to 9×10 ⁻⁶ /K. .. On the other hand, when the translucent member 30 is made of a silicone resin, the coefficient of thermal expansion of the translucent member 30 is 2 to 3×10 ⁻⁵ /K. Therefore, ΔT ₄₀ <ΔT ₃₀ can be satisfied by forming the covering members 40 and 403 from a material having a smaller coefficient of thermal expansion than silicone resin.

When a resin material is used for the covering members 40 and 403, the coefficient of thermal expansion is generally on the order of 10 ⁻⁵ /K, which is an order of magnitude higher than the coefficient of thermal expansion of a general light emitting element 20. However, the coefficient of thermal expansion of the resin material can be reduced by adding a filler or the like to the resin material. For example, by adding a filler such as silica to the silicone resin, the coefficient of thermal expansion can be made lower than that of the silicone resin before the filler is added.

The resin material that can be used for the covering members 40 and 403 is particularly preferably a thermosetting translucent resin such as silicone resin, silicone modified resin, epoxy resin, or phenol resin.

The covering members 40 and 403 can be formed of a light reflecting resin. The light-reflecting resin means a resin material having a reflectance of 70% or more for the light from the light emitting element 20. The light reaching the covering members 40 and 403 is reflected and travels toward the first surface 11 (light emitting surface) of the light emitting device 10, whereby the light extraction efficiency of the light emitting device 10 can be improved.

As the light-reflecting resin, for example, a light-transmitting resin in which a light-reflecting substance is dispersed can be used. As the light reflecting substance, for example, titanium oxide, silicon dioxide, titanium dioxide, zirconium dioxide, potassium titanate, alumina, aluminum nitride, boron nitride, mullite and the like are suitable. The light-reflecting substance may be granular, fibrous, thin plate-like, or the like, and fibrous substances are particularly preferable because the effect of lowering the coefficient of thermal expansion of the covering members 40 and 403 can be expected.

(Wavelength conversion member 50)
The wavelength conversion member 50 includes a phosphor and a translucent material. As the translucent material, translucent resin, glass or the like can be used. In particular, a light-transmitting resin is preferable, and a thermosetting resin such as a silicone resin, a silicone-modified resin, an epoxy resin, or a phenol resin, a thermoplastic resin such as a polycarbonate resin, an acrylic resin, a methylpentene resin, or a polynorbornene resin can be used. it can. In particular, a silicone resin having excellent light resistance and heat resistance is suitable.

A phosphor that can be excited by the light emitted from the light emitting element 20 is used. For example, as a phosphor that can be excited by a blue light emitting element or an ultraviolet light emitting element, a cerium-activated yttrium-aluminum-garnet-based phosphor (Ce:YAG); a cerium-activated lutetium-aluminum-garnet-based phosphor (Ce: LAG); europium and / or activated nitrogen containing calcium aluminosilicate phosphor chromium _{(CaO-Al 2 O 3 -SiO} 2); europium-activated silicates based phosphor ((Sr, Ba) ₂ SiO ₄ ); β-sialon phosphor, nitride phosphor such as CASN phosphor, SCASN phosphor; KSF phosphor (K ₂ SiF ₆ :Mn); sulfide phosphor, quantum dot phosphor And so on. By combining these phosphors with a blue light emitting element or an ultraviolet light emitting element, a light emitting device of various colors (for example, a white light emitting device) can be manufactured.
The wavelength conversion member 50 may contain various fillers for the purpose of adjusting viscosity.

The surface of the light emitting element may be covered with a translucent material containing no phosphor, instead of the wavelength conversion member 50. Further, the light-transmissive material may also contain various fillers for the purpose of adjusting viscosity.

Although some embodiments according to the present invention have been exemplified above, it is needless to say that the present invention is not limited to the above-mentioned embodiments and may be any one without departing from the gist of the present invention. ..
The disclosure content of the present specification may include the following aspects.
(Aspect 1)
A first surface, a second surface facing the first surface, and a plurality of side surfaces between the first surface and the second surface, and the second surface and the second surface. A light emitting element having a plurality of corners that are in contact with two of a plurality of side surfaces and having a pair of electrodes on the second surface side;
A translucent member that covers a part of at least one of the side surfaces and a part of a side where the at least one side surface and the second surface contact each other so as to expose one or more of the plurality of corner portions. ,
In order to expose the pair of electrodes, a covering member that covers the exposed corner portion of the light emitting element and the outer surface of the translucent member is included,
A light emitting device in which a difference in thermal expansion coefficient between the covering member and the light emitting element is smaller than a difference in thermal expansion coefficient between the light transmissive member and the light emitting element.
(Aspect 2)
A first surface, a second surface facing the first surface, and a plurality of side surfaces between the first surface and the second surface, and the second surface and the second surface. A light emitting element having a plurality of corners that are in contact with two of a plurality of side surfaces and having a pair of electrodes on the second surface side;
A translucent member that covers a part of at least one of the side surfaces and a part of a side where the at least one side surface and the second surface contact each other so as to expose one or more of the plurality of corner portions. ,
In order to expose the pair of electrodes, a covering member that covers the exposed corner portion of the light emitting element and the outer surface of the translucent member is included,
A light emitting device in which the thermal expansion coefficient of the covering member is lower than the thermal expansion coefficient of the translucent member.
(Aspect 3)
3. The light emitting device according to aspect 1 or 2, wherein the outer surface of the translucent member is inclined outward from the second surface side of the light emitting element toward the first surface side.
(Aspect 4)
The light emitting element has a substantially rectangular parallelepiped shape having four corners,
The light-emitting device according to any one of aspects 1 to 3, wherein two of the four corners located diagonally are covered by the covering member.
(Aspect 5)
The light emitting element has a substantially rectangular parallelepiped shape having four corners,
The two adjacent corners of the four corners and a part of the side between the two adjacent corners are covered by the covering member. Light emitting device.
(Aspect 6)
The light emitting device according to aspect 4 or 5, wherein all of the four corners are covered with the covering member.
(Aspect 7)
The light emitting device includes a transparent substrate and a semiconductor laminate,
7. The light emitting device according to any one of aspects 1 to 6, wherein the translucent substrate is arranged on the first surface side of the light emitting element, and the semiconductor laminated body is arranged on the second surface side. ..
(Aspect 8)
8. The light emitting device according to any one of aspects 1 to 7, wherein the translucent member is made of a translucent resin, and the covering member is made of a light reflective resin.
(Aspect 9)
The translucent member has a first surface that is flush with the first surface of the light emitting element,
9. The light emitting device according to any one of aspects 1 to 8, wherein the first surface of the light emitting element and the first surface of the translucent member are covered with a wavelength conversion member.
(Aspect 10)
The light emitting device according to any one of aspects 1 to 9, wherein the first surface of the light emitting element is covered with the translucent member.
(Aspect 11)
A step of preparing a wavelength conversion member,
Disposing the light emitting element on the wavelength conversion member such that the first surface of the light emitting element faces the second surface of the wavelength conversion member;
Forming a translucent member so as to cover a part of the side surface of the light emitting element and expose at least one corner of the light emitting element;
And a step of forming a covering member so as to cover the outer surface of the translucent member and the at least one corner of the light emitting element exposed from the translucent member.
(Aspect 12)
The step of forming the translucent member,
Disposing a liquid resin material on the wavelength conversion member,
12. The manufacturing method according to aspect 11, comprising disposing the light emitting element on the liquid resin material, and curing the liquid resin material to form the translucent member.
(Aspect 13)
The step of preparing the wavelength conversion member,
13. The manufacturing method according to aspect 11 or 12, which includes providing a through hole in the coating material layer and forming a phosphor-containing member in the through hole.
(Aspect 14)
14. The manufacturing method according to any one of aspects 11 to 13, wherein a difference in thermal expansion coefficient between the covering member and the light emitting element is smaller than a difference in thermal expansion coefficient between the light transmissive member and the light emitting element.

10, 15, 17 Light emitting device 11 First surface (top surface) of light emitting device
12 Second surface (lower surface) of light emitting device
20, 207 Light emitting element 21 First surface of light emitting element (upper surface)
22 Second surface (lower surface) of light emitting element
23 Side Surfaces of Light Emitting Element 241, 242, 243, 244 Corners of Light Emitting Element 251, 252 Electrode 30 Translucent Member 33 Outer Surface of Translucent Member 40 Covering Member 50 Wavelength Converting Member 500 Wavelength Converting Sheet 502 Phosphor Containing Member 510 Wavelength conversion layer

Claims (5)

A step of preparing a wavelength conversion member,
The first surface of the light emitting element and the second surface of the wavelength conversion member are opposed to each other, and an adhesive is arranged between the first surface of the light emitting element and the second surface of the wavelength conversion member. Then, a step of fixing the light emitting element on the wavelength conversion member,
Forming a translucent member so as to cover a part of the side surface of the light emitting element and a part of the second surface of the wavelength conversion member outside the region where the light emitting element is fixed; ,
A step of forming a covering member so as to cover the outer surface of the translucent member,
Only including,
The light emitting element has a third side where two adjacent side surfaces of the light emitting element are in contact with each other,
The step of forming the translucent member,
The liquid resin material serving as the translucent member covers part of the third side of the light emitting element and does not reach the corner of the light emitting element that is the end of the third side. Including,
The step of forming the covering member includes
The covering member, the liquid resin material reaches non corner covering that including a light emitting device, method of manufacturing the light emitting device. The step of forming the translucent member,
Disposing a liquid resin material on the wavelength conversion member, and
The method for manufacturing a light emitting device according to claim 1, further comprising curing the liquid resin material to form the translucent member. The method for manufacturing a light emitting device according to claim 1, wherein a difference in thermal expansion coefficient between the covering member and the light emitting element is smaller than a difference in thermal expansion coefficient between the light transmissive member and the light emitting element. The light emitting element has a first side surrounding the first surface of the light emitting element,
The step of forming the translucent member,
The liquid resin material which becomes the translucent member is arrange|positioned along the boundary of the said 1st side of the said light emitting element, and the said wavelength conversion member, The any one of Claims 1-3 characterized by the above-mentioned. Method for manufacturing light emitting device. The light emitting element has a second surface facing the first surface of the light emitting element, and a second side surrounding the second surface,
The step of forming the translucent member,
The method for manufacturing a light emitting device according to claim 1, further comprising contacting a part of the second side of the light emitting element with a liquid resin material serving as the translucent member.

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