JP2011108914A - Semiconductor light-emitting device and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor light-emitting device capable of maintaining a structure with a substrate and a semiconductor light-emitting element being brought into contact without fail. <P>SOLUTION: The semiconductor light-emitting device, having a plurality of light-emitting elements sandwiched inbetween a pair of substrates at least one of which has transparency, has first insulating adhesives and second insulating adhesives between adjacent semiconductor light-emitting elements such that the first insulating adhesives are arranged covering side surfaces of the respective semiconductor light-emitting elements and the second insulating adhesives are arranged between the first insulating adhesives. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a semiconductor light emitting device using a semiconductor light emitting element and a method for manufacturing the same, and more particularly, to a semiconductor light emitting device and a manufacturing method for sandwiching a semiconductor light emitting element between upper and lower sides.

  The demand for thinning and cost reduction of light-emitting devices used for backlights used in thin displays and lighting devices placed on wall surfaces, etc., has been increasing with the progress of thinning and space saving of these displays and lighting devices. is doing.

  In a typical conventional semiconductor light emitting device, it is necessary to mount each semiconductor light emitting element on a mounting substrate or the like and perform wiring by performing wire bonding or the like. When wire bonding is performed, there is a problem that the light emitting device becomes large at least as much as the height of the wire and the manufacturing process becomes complicated. Therefore, as in Patent Documents 1 to 4, a semiconductor light emitting device is proposed in which a plurality of semiconductor light emitting elements are arranged between two conductive substrates. In such a semiconductor light emitting device, since it is not necessary to electrically connect each semiconductor light emitting element to the positive electrode and the negative electrode by a method such as wire bonding, the thickness and cost can be reduced.

JP 2009-010204 Japanese Utility Model Publication No. 06-010982 JP 2008-034473 A Japanese Patent Laid-Open No. 11-177147

  In the semiconductor light emitting devices as disclosed in Patent Documents 1 to 4, an insulating adhesive is provided between the substrates in order to protect the semiconductor light emitting elements and prevent the substrates from contacting each other. However, if the adhesive pulls the substrates together to hold the semiconductor light emitting element (hereinafter referred to as “holding force”) is too strong, the substrate or the semiconductor light emitting element is cracked or cracked. Driving may be difficult. On the other hand, when the clamping force is too small, there is a possibility that the light emitting element is not lighted due to poor contact between the conductive substrate and the semiconductor light emitting element, and further, the substrate is peeled off.

  Therefore, an object of the present invention is to obtain a semiconductor light emitting device capable of maintaining a structure in which the substrate and the semiconductor light emitting element are reliably in contact with each other in a light emitting device in which the upper and lower sides of the light emitting element are sandwiched between the substrates.

The semiconductor light-emitting device of the present invention is a semiconductor light-emitting device in which a plurality of semiconductor light-emitting elements are sandwiched between a pair of light-transmitting substrates, at least one of which has a first insulating property between adjacent semiconductor light-emitting elements. An adhesive and a second insulating adhesive are provided, the first insulating adhesive is disposed so as to cover the side surface of each semiconductor light emitting element, and the second insulating adhesive is interposed between the second insulating adhesives. An insulating adhesive is arranged.
Further, it is preferable that the second insulating adhesive is disposed so as to contact the first insulating adhesive and includes an elastic material.
The elastic material is preferably a sphere having a diameter smaller than the thickness of the semiconductor light emitting element.
Moreover, it is preferable that the refractive index of a said 2nd insulating adhesive is larger than the refractive index of a said 1st insulating adhesive.
It is preferable that the linear expansion coefficient of the second insulating adhesive is smaller than the linear expansion coefficient of the first insulating adhesive.
Preferably, the first insulating adhesive is a silicone resin, and the second insulating adhesive is an epoxy resin.
It is preferable that at least one of the substrates is a glass substrate provided with a translucent conductive film.

According to another aspect of the present invention, there is provided a method for manufacturing a semiconductor light emitting device, comprising: a step of disposing a second insulating adhesive on a substrate; a step of semi-curing the second insulating adhesive; and a semiconductor light emitting element. 1 is disposed on the substrate, and the semiconductor light-emitting element is sandwiched by using the substrate and a substrate different from the substrate, and the first insulating adhesive and the second And an adhesive curing step for curing the insulating adhesive.
In the adhesive curing step, it is preferable that the first insulating adhesive and the second insulating adhesive are arranged on the substrate so as to come into contact with each other.
Moreover, it is preferable to include a step of mixing an elastic material with the second insulating adhesive before disposing the second insulating adhesive on the substrate.

  In the semiconductor light emitting device of the present invention, the first insulating adhesive and the second insulating adhesive are provided between adjacent semiconductor light emitting elements, and the first light emitting device covers the side surfaces of the respective semiconductor light emitting elements. Insulating adhesive is disposed, and the second insulating adhesive is disposed between the first insulating adhesives, thereby maintaining a structure in which the substrate and the semiconductor light emitting element are reliably brought into contact with each other. Can do.

It is a schematic sectional drawing for demonstrating the structure of the semiconductor light-emitting device of this invention. FIG. 2 is a partially enlarged view of FIG. 1 for explaining the structure of the semiconductor light emitting device of the present invention. It is a schematic sectional drawing for demonstrating the structure of the semiconductor light-emitting device of this invention. It is the top view and side view for demonstrating the manufacturing method of the semiconductor light-emitting device of this invention. It is the top view and side view for demonstrating the manufacturing method of the semiconductor light-emitting device of this invention. It is the top view and side view for demonstrating the manufacturing method of the semiconductor light-emitting device of this invention. It is the top view and side view for demonstrating the manufacturing method of the semiconductor light-emitting device of this invention. It is a top view for demonstrating the structure of the semiconductor light-emitting device of another form of this invention.

A mode for carrying out the present invention will be described with reference to the drawings. However, the form shown below is an example, does not limit the present invention, and the present invention is not limited to the dimensions, materials, shapes, relative arrangements, and the like of the components described. Note that the size, positional relationship, and the like of the members shown in each drawing may be exaggerated for clarity of explanation. In order to simplify the description, the same constituent elements are denoted by the same reference numerals, and a part of the description is omitted.
For convenience of explanation, the “substrate 10a” may be referred to as a “first substrate” and the “substrate 10b” may be referred to as a “second substrate”.

1 and 2 show an example of the semiconductor light emitting device of the present invention. FIG. 1 is a sectional view of a semiconductor light emitting device of the present invention, and FIG. 2 is an enlarged view of a circled portion in FIG. FIG. 3 shows a cross-sectional view of the semiconductor light emitting device used in the present invention.
As shown in FIG. 1, the semiconductor light emitting device 100 of the present invention has a plurality of semiconductor light emitting elements 20 sandwiched between conductive substrates 10a and 10b. Between the adjacent semiconductor light emitting elements, the first insulating adhesive 31 disposed so as to cover the side surfaces of the respective semiconductor light emitting elements and the second insulating adhesive disposed between the first insulating adhesives. Insulating adhesive 32. In addition, a part of the conductive substrates 10a and 10b is exposed and serves as connection portions 12a and 12b to the outside. As shown in FIG. 2, conductive films 11 a and 11 b are provided on the surface of the substrate in this embodiment, and the second insulating adhesive contains an elastic material 33.

Each configuration of the present invention will be described.
(Semiconductor light emitting device)
The semiconductor light-emitting element used in the present invention is sandwiched between a pair of substrates arranged to face each other. For example, one of them is a p-side electrode and the other is an n-side electrode, and light can be emitted by applying a voltage. By forming electrodes above and below the semiconductor layer, the semiconductor light emitting device itself can be miniaturized. Further, since a plurality of semiconductor light emitting elements can be dispersed and arranged on the conductive substrate, the heat dissipation of the semiconductor light emitting device can be improved. Or the structure by which the p side electrode and the n side electrode were provided in the same surface side may be sufficient.
Moreover, visible light, ultraviolet light, etc. can be selected as the luminescent color of the semiconductor light-emitting element 20. In the case of visible light, the emission color is not limited, and any of a green semiconductor light emitting element, a red semiconductor light emitting element, and a blue semiconductor light emitting element can be used. Further, the semiconductor material is not particularly limited, and any compound such as III-V group or II-VI group may be used.

  For example, as shown in FIG. 3, the semiconductor light emitting device 20 includes an n-type semiconductor layer 22, an active layer 23, and a p-type semiconductor layer 24 provided on a conductive growth substrate 21, and an upper surface of the p-type semiconductor layer. A p-side electrode 25 and an n-side electrode 26 are provided on the back surface of the growth substrate. The semiconductor light emitting device 20 is preferably an upper and lower electrode type semiconductor light emitting device having electrodes on the upper and lower surfaces thereof, but the electrodes are omitted if the structure can supply current from the conductive substrate 10a or 10b. May be. Further, after forming the semiconductor layer using the conductive or insulating growth substrate 21, the growth substrate may be removed and only the semiconductor layer may be formed, or another support substrate may be provided on the surface side of the semiconductor layer. Etc. may be provided.

  The size of the semiconductor light emitting element 20 is 350 μm or less in the vertical and horizontal directions (a direction perpendicular to the paper surface of FIG. 1 and a direction parallel to the substrate 10 on the paper surface of FIG. 1) when viewed from above. The direction perpendicular to the substrate 10 on the paper surface of FIG. 1 is preferably 100 μm or less. More preferably, the length and width are 100 μm or less and the thickness is 50 μm or less.

(substrate)
As shown in FIG. 2, the substrate in the present embodiment is provided with conductive films 11a and 11b on opposing surfaces (inner surfaces) of the pair of substrates 10a and 10b. The substrate is used to sandwich a plurality of semiconductor light emitting elements, and defines the outer shape of the semiconductor light emitting device. Further, when conductivity is imparted to at least one surface, the substrate may be referred to as a conductive substrate. In addition, when the p-side electrode and the n-side electrode are provided on the same surface side of the semiconductor light emitting element, both the substrates do not need to be conductive, and at least the substrate in contact with the electrode is imparted with conductivity. It only has to be.

  At least one of the substrates is preferably translucent. Thereby, the light which passed the translucent board | substrate is radiate | emitted and it can be set as a planar semiconductor light-emitting device. In the case where one substrate is light-transmitting, the light extraction efficiency can be improved by providing a reflective film on the other substrate. Alternatively, both substrates may be light-transmitting so that a double-sided light emitting semiconductor light-emitting device is obtained. Note that in this specification, the light-transmitting property refers to a material having a light transmittance of 50% or more from a semiconductor light-emitting element or a phosphor in a thickness applied to a semiconductor light-emitting device.

  As the substrate material, non-conductive (insulating) transparent resin such as polyimide, glass, rolled metal, or the like can be used as the base material 10. In the case of using a substrate made of a conductive material, the conductive film can be omitted. The conductive film only needs to be provided at least in a region where the semiconductor light emitting element and the substrate are connected, and may be partially provided on the substrate. It is preferable to be provided on the entire surface from the viewpoint of securing a conductive portion with the outside. As the conductive film 11 provided over the substrate, a known material can be used as appropriate. In particular, an oxide light-transmitting conductive film such as indium tin oxide (ITO), indium oxide, zinc oxide, tin oxide, or the like, has a structure in which light is transmitted using a metal film in a mesh shape or a lattice shape, or It is preferable to form a metal such as Ag, Au, Cu, and Ni as a thin film that maintains light transmittance. For example, when a light-transmitting substrate is used, it is preferable to form ITO as a light-transmitting conductive film on a glass substrate. Further, when a reflective film is provided on the substrate, it is preferable to provide a metal film made of Ag on the surface in contact with the semiconductor light emitting element. In this case, since the base material of the substrate does not need to have translucency, the material can be arbitrarily selected, and it is preferable to use a conductive substrate made of Cu from the viewpoint of heat dissipation.

  For the conductive substrate, a flexible material having ductility and malleability can be used. Since semiconductor light emitting elements are usually manufactured in a wafer state, the thickness of each element may vary. In a semiconductor light emitting device using a plurality of semiconductor light emitting elements, a thin semiconductor light emitting element may not emit light because no current flows due to poor contact with the conductive substrate. By using a flexible substrate, a thin semiconductor light emitting element and a conductive substrate can be brought into contact with each other, and light emission unevenness can be suppressed by eliminating elements that do not emit light. As the flexible substrate, a known material can be used, and examples thereof include a substrate in which polyimide, epoxy, and Cu are sequentially laminated.

  Further, the shape of the substrate can be arbitrarily selected from a rectangle, a circle, an ellipse, and the like. Further, the size of the substrate can be set to a desired size according to the required size of the semiconductor light emitting device. For example, in the case of a rectangle, the size of one side is about 5 to 30 cm. Moreover, as thickness of a board | substrate, when using glass, about 30 micrometers-3 mm are used, and when using a flexible substrate, about 10 micrometers-100 micrometers are mentioned.

Further, the conductive substrate may have a multilayer structure, and in addition to the conductive film, a film that imparts various functions can be provided. For example, a metal, an oxide, or a resin can be provided as appropriate as an adhesion layer or a barrier layer provided between the substrate and the conductive film. For example, Ni, SiO _2, epoxy, and the like. Further, epoxy, polyimide, or the like can be provided as a protective layer for protecting the outside of the substrate.
Further, a structure in which a phosphor mixed film is formed on the inner surface or the outer surface of a light-transmitting substrate, and the wavelength of light emitted from the semiconductor light emitting element may be converted. For example, in a semiconductor light emitting device that sandwiches a nitride semiconductor light emitting element that emits blue light on a glass substrate, white light can be obtained by applying silicone mixed with YAG onto the glass substrate. Alternatively, the glass itself can contain a phosphor.

  When a glass substrate is used as the conductive substrate, it is easy to extract light through the conductive substrate. The materials may adhere and cause a short circuit. However, by applying the present invention, since different types of insulating adhesives are periodically arranged in the light emitting device, the bending of the substrates due to stress is absorbed, and the adhesive force between the substrates in a specific region is increased. A semiconductor light-emitting device having a stable structure can be obtained without becoming strong or having a weak adhesive force and peeling off.

  Moreover, it is preferable that the connection part 12 with the exterior is provided in the surface of a conductive substrate. The connection portion is the surface of the substrate that is exposed so that the conductive film is not covered with the insulating adhesive so as to be connected to the outside. For example, the light emitting element on which the semiconductor light emitting element or the insulating adhesive is disposed Examples include a conductive substrate exposed adjacent to the region to provide a connection portion. In addition, as illustrated in FIG. 1, the connection portion can be provided by disposing the first conductive film and the second conductive film so as to be partially exposed. When the entire conductive substrate is formed of a conductive material, it is not necessary to provide a connection portion on the surface to which the semiconductor light emitting element is bonded (the inner surface of the conductive substrate), and the side away from the semiconductor light emitting element You may provide a connection part in the surface (outer surface).

The number and distribution density of the semiconductor light emitting elements 20 arranged in the semiconductor light emitting device are determined in consideration of heat generation and heat dissipation characteristics due to light emission. For example, when the vertical and horizontal sizes of the semiconductor light emitting elements are about 100 μm. The number of the semiconductor light emitting elements is preferably 100 or less per 10 cm square (area 100 cm ² ) of the substrate 10. Further, when the vertical and horizontal sizes of the semiconductor light emitting elements are about 10 μm, the number of semiconductor light emitting elements is preferably 10,000 or less per 10 cm square of the substrate 10.

(Insulating adhesive)
It is preferable that the insulating adhesive used in the present invention is provided between the substrates and is filled except for a portion where the semiconductor light emitting element is disposed. It is provided to protect the semiconductor light emitting element and prevent contact between the substrates. Further, from the viewpoint of light extraction efficiency, it is preferably formed of a highly transparent material.
Specific examples of the material include silicone resin, epoxy resin, acrylic resin, fluororesin, polyimide resin, and light-transmitting thermoplastic or thermosetting resin such as various hot melts.

As the insulating adhesive of the present invention, a first insulating adhesive and a second insulating adhesive are provided. As in the present invention, by filling two kinds of insulating adhesives between the substrates in a predetermined arrangement, it is possible to maintain a structure in which the substrate and the semiconductor light emitting element are reliably brought into contact with each other. When the adhesive is cured, it contracts or expands, so that the pinching force changes from the time when the adhesive is applied. In addition, deterioration may occur due to the passage of time or driving for a long time, and the clamping force may change. Specifically, if the sandwiching force of the adhesive is too strong, cracks or the like may occur in the substrate or the semiconductor light emitting element, and it may be difficult to drive the semiconductor light emitting element. On the other hand, when the clamping force is too small, there is a possibility that the light emitting element is not lighted due to poor contact between the conductive substrate and the semiconductor light emitting element, and further, the conductive substrate is peeled off.
Further, depending on the adhesive, the conductive substrates may contact each other without being able to absorb the bending of the substrates. As a result of such a change, an electrical resistance is increased or an element that does not emit light is generated, resulting in uneven color development and light distribution as a device, thereby preventing a change in clamping force after the insulating adhesive is cured. There is a need. In the present invention, since they are distributed and arranged using at least two kinds of insulating adhesives, it is possible to securely bond the substrates to each other and maintain the structure, and to prevent the substrate from cracking. it can. In addition, the adhesive strength of the adhesive is weakened and the substrate is not peeled off, so that a semiconductor light emitting device having a stable structure can be obtained.

(First insulating adhesive)
The first insulating adhesive 31 has a role of protecting the side surface of the semiconductor light emitting element. Therefore, it is preferable to be disposed in contact with the semiconductor light emitting element. Since it is arranged close to the semiconductor light emitting element, if the clamping force of the first insulating adhesive is too strong, not only is the load applied to the semiconductor light emitting element, but also the conductive film or substrate in the vicinity thereof is cracked. And cracking may occur. Therefore, it is preferable that the first insulating adhesive has little shrinkage after curing. Further, the light density is high in the region where the first insulating adhesive is disposed. Therefore, it is preferable that the first insulating adhesive has high light resistance and little deterioration due to light. Thereby, a lifetime characteristic can be improved. The thickness of the first insulating adhesive only needs to cover at least the side surface, and preferably has a thickness of about 0.01 to 0.5 mm from the side surface of the semiconductor light emitting element. In addition, when arranged on the substrate in a state of being mixed with the semiconductor light emitting device, the viscosity or softness is such that the insulating adhesive located on the upper surface and the lower surface of the semiconductor light emitting device is moved by pressing the second substrate. It is preferable to have.
Specific examples of the first insulating adhesive include silicone resin and fluorine resin. Among them, it is preferable to use dimethyl silicone or CYTOP manufactured by Asahi Glass Co., Ltd. as a material that satisfies the above characteristics.

(Second insulating adhesive)
The second insulating adhesive is disposed between the first insulating adhesives. By disposing the second insulating adhesive in this manner, a structure with stable adhesiveness in the surface can be obtained, and a semiconductor light emitting device with little characteristic change even during driving can be obtained. That is, since the first substrate and the second substrate are bonded, a substrate having a large clamping force, that is, a substrate having a large shrinkage after curing is preferable. Even if the distance between the substrates is reduced due to the shrinkage after curing the adhesive, it is placed at a position away from the semiconductor light emitting element, so that the strength as a device is maintained with little influence on the semiconductor light emitting element. Can do.
In addition, a gap may be provided between the first insulating adhesive and the second insulating adhesive, but it is preferable that both are provided in contact with each other. By filling the space between the substrates with an insulating adhesive, the adhesion of the substrates and the light distribution of the semiconductor light emitting device can be stabilized.
The linear expansion coefficient of the second insulating adhesive is preferably smaller than the linear expansion coefficient of the first insulating adhesive. By using a second insulating adhesive having a low linear expansion coefficient as the second insulating adhesive to which the substrates are bonded together, the bonding between the substrates can be stabilized, and a semiconductor light emitting device with little characteristic change even at high temperature operation Can do.
Specifically, an epoxy resin is preferably used as the second insulating adhesive. Even during high-temperature operation and long-time driving, the insulating adhesive is hardly denatured and expanded, and poor conduction can be prevented.
Moreover, it is preferable that the refractive index of a 2nd insulating adhesive is larger than the refractive index of a 1st insulating adhesive. This is because the light extraction efficiency can be improved by the light diffusion effect at the interface with the first insulating adhesive.
Moreover, it is preferable to use a thermosetting resin as the second insulating adhesive. Although details will be described later, the conduction failure can be greatly reduced.
Further, another insulating adhesive may be optionally provided between the first insulating adhesive and the second insulating adhesive. In addition, the ratio of the arrangement of the first insulating adhesive and the second insulating adhesive is not particularly limited and can be arbitrarily selected.

(Elastic material)
As shown in FIG. 2, it is preferable to include an elastic material 33 in the insulating adhesive. The elastic material is provided to prevent the conductive substrates from contacting each other. Therefore, the elastic material is required to be insulating. Further, it is preferable to have elasticity and / or strength that does not cause cracking or chipping due to the stress when sandwiched between the substrates. As the elastic material, spherical beads made of plastic or rubber can be used. Specifically, Sekisui Chemical Co., Ltd. Micropearl EX, Natoko Co., Ltd. Natoko Spacer, Shin-Etsu Chemical Co., Ltd. silicone rubber powder, etc. can be used.
The size of the elastic material is preferably smaller than the thickness of the semiconductor light emitting element. This is because the semiconductor light emitting element and the conductive substrate are reliably brought into contact with each other when the conductive substrates are bonded together. Moreover, it is preferable that it is a magnitude | size of at least about 1 micrometer or more.
The elastic material is preferably mixed with the second insulating adhesive. Although details will be described later, if the elastic material adheres to the surface of the semiconductor light emitting element, cracks or cracks are generated in the semiconductor light emitting element, but this can be prevented. Moreover, it is preferable that an elastic material is formed with a translucent material.

(Auxiliary electrode)
As shown in FIG. 8, the auxiliary electrode 40 may be provided on the surface of at least one of the conductive substrates. The auxiliary electrode is preferably provided between the substrate and the conductive film or between the conductive film and the insulating adhesive. In the light-emitting device of the present invention, the connection portion 12 is connected to an external power supply. However, current does not easily flow in a region far from the connection portion 12, and uneven light emission may occur. By providing the auxiliary electrode, light emission with uniform intensity can be obtained in the plane. In the case of using a light-transmitting substrate, the conductive film formed on the surface of the substrate is often formed using a thin film to ensure light-transmitting properties. When formed of a thin film, the light-transmitting property can be secured, but the current supply to the light emitting element tends to be insufficient. In such a case, it is effective to provide an auxiliary electrode.
The auxiliary electrode preferably has a width of about 10 to 500 μm and a length that is about the same as the length from the end on the connection side to the opposite side. The thickness of the auxiliary electrode is preferably at least thinner than the thickness of the semiconductor light emitting element, and specifically, it is preferably about 0.1 to 30 μm. The auxiliary electrodes are preferably arranged with an interval of about 1 to 10 mm. As a position where the auxiliary electrode is disposed, it is effective to dispose the auxiliary electrode so that the position is 0.5 to 5 mm from the light emitting element. The shape of the auxiliary electrode is not particularly limited. A plurality of conductive films partially provided over the substrate may be connected.
Specific materials for the auxiliary electrode include Ag, Au, Cu and the like.
Further, the conductive film may be provided using the same material or a different material. As a method for forming the auxiliary electrode, a known method such as sputtering, plating, printing, or dispenser can be appropriately used.

  Hereinafter, a method for manufacturing a semiconductor light emitting device of the present invention will be described with reference to FIGS. 4 to 7, (a) shows a top view and (b) shows a side view.

First, as shown in FIG. 4, a conductive substrate is prepared, and a second insulating adhesive 32 is disposed on the first conductive substrate 10a. The second insulating adhesive is preferably arranged so that a predetermined amount is distributed on the conductive substrate. Specifically, it is preferable to arrange about 0.01 to 10.0 μl per location and arrange them on the substrate with a spacing of about 1 to 10 mm. As a specific application method, a dispenser or screen printing can be used.
Moreover, it is preferable that the second insulating adhesive is disposed on the first conductive substrate at substantially equal intervals. Thereby, it can be used as a mark for arranging the semiconductor light emitting elements in a later step, and uniform light emission can be obtained by arranging the semiconductor light emitting elements at equal intervals.

  Moreover, it is preferable that after the second insulating adhesive is applied, the viscosity is increased so as not to flow. For example, it is preferably semi-cured by heating or irradiation with ultraviolet light. When using a resin adhesive, it is preferable to be in a B-stage state, for example. As heating conditions, about 50-100 degreeC and about 10-60 minutes are mentioned. This is preferable because the adhesive does not flow and the subsequent handling is easy.

The second insulating adhesive preferably includes an elastic material. By disposing the elastic material prior to mounting the semiconductor light emitting element, it is possible to prevent the elastic material from adhering to the upper surface of the semiconductor light emitting element. Further, by disposing the second insulating adhesive containing the elastic material so as to be distributed at a predetermined position, the second insulating adhesive is different from the portion where the second insulating adhesive is applied when the semiconductor light emitting element is disposed. By simply arranging the semiconductor light emitting element at the position, the contact between the semiconductor light emitting element and the elastic material can be prevented, and the occurrence of cracks in the light emitting element can be suppressed.
Alternatively, the second insulating adhesive may be disposed on the first conductive substrate by dispenser or screen printing, and then the elastic material may be included in the second insulating adhesive using a spray or the like. Good. At this time, it is preferable that a mask or the like is provided as appropriate in a region where the semiconductor light emitting element is arranged so that the elastic material does not adhere, and the mask is removed before the semiconductor light emitting element is arranged.

  Subsequently, as shown in FIG. 5, a first insulating adhesive 31 including the semiconductor light emitting element 20 is disposed on the conductive substrate. By mixing the semiconductor light emitting element with the first insulating adhesive in advance and applying it to the conductive substrate, handling during the process can be improved. This is particularly advantageous when a small semiconductor light emitting element (for example, 100 μm or less) is used. Specifically, when a semiconductor light emitting element is mounted on a mounting board or the like, it is generally adsorbed by a collet or the like and transported onto the mounting board, but the size that the collet can be adsorbed is limited. The smaller the light emitting element is, the more difficult it is to transport it to a desired position. However, by mixing the semiconductor light emitting element in advance with the first insulating adhesive and sucking the volume including the insulating adhesive with a dropper or the like, even a small semiconductor light emitting element can be conveyed to a desired position. Can be arranged. Moreover, it is preferable to arrange | position in the location different from the area | region which applied the 2nd adhesive agent. In addition, when the insulating adhesive is cured in a later step, it is preferable to arrange the first insulating adhesive and the second insulating adhesive so as to contact each other. For example, it may be arranged within 0.5 to 5 mm from the second insulating adhesive arranged previously. Moreover, it is preferable to arrange about 0.001 to 3 μl per one place. As a specific application method, a dispenser or the like can be used. Alternatively, the first insulating adhesive may be disposed on the first conductive substrate by dispenser or printing, and then the semiconductor light emitting element may be included in the first insulating adhesive using a spray or the like. Good. Thereby, it becomes easy to contact the semiconductor light emitting element and the second conductive substrate in a later step. In addition, the semiconductor light emitting device can be arranged in a separate process. In that case, the first insulating adhesive can also be formed by screen printing, and examples of the arrangement of the semiconductor light emitting element include a method of transferring with an adhesive sheet or the like.

Further, the insulating adhesive and / or the semiconductor light emitting element may be arranged irregularly or regularly. Although a plurality of semiconductor light emitting elements may be arranged close to each other, it is preferable that the semiconductor light emitting elements are arranged apart from each other from the viewpoint of dispersing the heat source.
Moreover, the direction of the electrodes of each semiconductor light emitting element 20 may be aligned so that one of the electrodes is all positive or negative. Alternatively, a semiconductor light-emitting element having a positive electrode on the side in contact with the first conductive substrate and a semiconductor light-emitting element having a negative electrode on the upper electrode may be mixed (with the electrodes not aligned).
Further, in the case of using a semiconductor light emitting element in which electrodes are formed on the same surface side, the first substrate or the second substrate can be made of an insulating material, and the direction of the electrodes is a conductive substrate. It is preferable to arrange so as to be on the side.

  Next, as shown in FIG. 6, the second conductive substrate is arranged so that the surfaces on which the conductive film is formed face each other. As shown in FIG. 1, it is preferable to arrange a pair of substrates having the same size so as not to overlap each other so that the end portions are exposed, and to provide a connection portion. With this configuration, it is not necessary to provide a connection portion on the outer surface of the light-emitting device, and the strength of the semiconductor light-emitting device can be increased by providing a protective layer with an insulating film or the like on the outside. In addition, the first insulating adhesive and / or the second insulating adhesive is used to fill the gap between the conductive substrates with the insulating adhesive before the second conductive substrate is placed and cured. May be injected.

Finally, as shown in FIG. 7, a pressure is applied to the second conductive substrate so that the first conductive substrate and the second conductive substrate are bonded together to sandwich the semiconductor light emitting element, and the first insulating adhesion is performed. The semiconductor light emitting device can be obtained by curing the agent and the second insulating adhesive. By pressurizing the second conductive substrate, the first insulating adhesive wraps around the side surface of the semiconductor light emitting element, and the semiconductor light emitting element contained in the first insulating adhesive has the first conductive property. It can be brought into electrical contact with the substrate. When the elastic material is disposed above or below the semiconductor light emitting device, the semiconductor light emitting device is cracked or cracked by pressurizing the substrate. However, according to the manufacturing method of the present invention, this is surely prevented. can do. Examples of the curing method for the insulating adhesive include heating and irradiation with ultraviolet light.
As a specific pressurizing method, a known method such as a roller can be used. In addition, it is preferable to soften the first insulating adhesive by heating at this time. As heating conditions, it is preferable to carry out in about 120-180 degreeC and about 10-60 minutes. In addition, it is preferable that the conductive substrate is bonded so that the first insulating adhesive and the second insulating adhesive are in contact with each other. The light extraction can be improved by preventing the voids from being formed.
Further, after the conductive substrates are bonded together, the both may be bonded firmly using a pressure roller or the like.

Further, the driving method of the semiconductor light emitting element is preferably direct current driving or direct current pulse driving when the direction of the electrode is uniform, while preferably the alternating current when the direction of the electrode is not uniform. Sine wave drive and AC pulse drive.
The supplied current is preferably 10 mA or less per semiconductor light emitting element, and is preferably set to 1 W or more and 10 W or less per 10 cm square of the conductive substrate 10.
In addition, the semiconductor light emitting device thus obtained may be arbitrarily divided and used as a light emitting device.

Examples of the semiconductor light emitting device of the present invention are shown below.
<Example 1>
In the semiconductor light emitting device 100 of the present embodiment as shown in FIG. 1, a plurality of nitride semiconductor light emitting elements 20 are disposed between conductive substrates 10a and 10b each having a transparent conductive film made of ITO on a glass substrate. ing. In this semiconductor light emitting device, as shown in FIG. 3, an n-type nitride semiconductor layer, an active layer, and a p-type nitride semiconductor layer are formed on a GaN substrate, and the p-type nitride semiconductor layer is made of ITO with p. The side electrode is formed of Ti / Au on the back surface of the substrate. Between the semiconductor light emitting elements, a silicone resin is used as a first insulating adhesive covering the side surface of the semiconductor light emitting element, and an epoxy is used as a second insulating adhesive provided between the first insulating adhesives. Filled with resin. Further, as shown in FIG. 1, the conductive substrates face each other so that the end portions are exposed to each other, and are connected to the outside through the connection portions 12 at the exposed end portions.

  The semiconductor light-emitting device of this example is a double-sided light-emitting type semiconductor light-emitting device, and light that has passed through the conductive substrate 10 is emitted in the vertical direction side of FIG. Of the emitted light, the light directed upward from the semiconductor light emitting element 20 is transmitted through the upper conductive substrate 10 b and extracted outside the semiconductor light emitting device 100. Further, the light directed downward from the semiconductor light emitting element 20 passes through the lower conductive substrate 10 a and is extracted out of the semiconductor light emitting device 100. Further, the light emitted to the side of the semiconductor light emitting element is scattered at the interface between the first adhesive and the second adhesive, proceeds upward or downward, and is emitted to the outside.

Such a semiconductor light emitting device can be manufactured by the following method.
First, two sheets of ITO with 10 nm formed on one surface of a glass substrate having a size of 5 cm square and a thickness of 700 μm are prepared. As shown in FIG. 4, 6 μl of the second insulating adhesive is applied to the surface of one conductive substrate (first conductive substrate) on which ITO is formed using a dispenser. At this time, a predetermined amount is applied on the substrate at equal intervals of 10 mm pitch, and the outer peripheral edge of one side is exposed with a width of about 5 mm.
Thus, what applied the 2nd insulating adhesive on the 1st conductive board | substrate is hold | maintained for 60 minutes at 80 degreeC with a heating apparatus, A 2nd insulating adhesive is a B stage state And

  Subsequently, as shown in FIG. 5, the first insulating adhesive is applied to the exposed region of the first conductive substrate, and the first insulating adhesive including a semiconductor light emitting element having a thickness of 100 μm square and a thickness of 75 μm. The agent is applied 1.5 μl at a time, and 16 semiconductor light emitting elements are arranged.

  Subsequently, as shown in FIG. 6, the other conductive substrate (second conductive substrate) is disposed so that the surfaces on which the ITO is formed face each other. At this time, the first conductive substrate and the second conductive substrate are arranged so as to be shifted so that the outer peripheral end exposed first is exposed.

Subsequently, as shown in FIG. 7, the semiconductor light emitting element, the first insulating adhesive, and the second insulating adhesive are sandwiched between a pair of conductive substrates, and vacuuming is performed and pressure is applied. At this time, it is heated and held at about 150 ° C. The first insulating adhesive around the semiconductor light emitting element moves to the side of the element by the pressing of the second conductive substrate and covers the side surface of the light emitting element. The second insulating adhesive is softened by heating and is in close contact with the second conductive substrate.
A semiconductor light emitting device can be obtained as described above.

In the semiconductor light emitting device of this example, the adhesiveness between the conductive substrates is high, and no lapse of time, long time driving, and no peeling or cracking of the substrate during high temperature operation are observed. Further, since the substrates are firmly bonded to each other, the adhesion between the semiconductor light emitting element and the conductive substrate is also good.
In addition, according to the manufacturing method of this embodiment, the first insulating adhesive and the second insulating adhesive can be reliably distributed and arranged on the first conductive substrate.

<Example 2>
The difference of the present embodiment from the first embodiment is that, as shown in FIG. 2, the second insulating adhesive contains an elastic material. Specifically, the second insulating adhesive includes the second insulating adhesive. Micropearl EX manufactured by Sekisui Chemical Co., Ltd. is included. After the elastic material is mixed with the second insulating adhesive by about 0.3 wt%, the second insulating adhesive is applied to the first conductive substrate. Other than that, it produces similarly to Example 1. FIG.
Compared with the semiconductor light-emitting device of Example 1, the semiconductor light-emitting device of this example can reduce defects due to contact between conductive substrates. Further, since the elastic material does not enter the upper surface or the lower surface of the semiconductor light emitting device, the semiconductor light emitting device does not have poor conduction or cracks.

<Example 3>
The difference of the present embodiment from the first embodiment is that a reflective metal substrate is used for the second conductive substrate. Specifically, Ni (5 μm) is interposed on Cu (300 μm). A conductive film (2 μm) made of Ag is formed. Other than that, it produces similarly to Example 1. FIG. The semiconductor light emitting device of this embodiment is different from the light emitting device of Embodiment 1 in that light is reflected on the second conductive substrate side and light is emitted only on the first conductive substrate side.
In the semiconductor light emitting device of this example, compared with Example 1, the second conductive substrate has conductivity and high thermal conductivity, and therefore has excellent heat dissipation. Therefore, the semiconductor light emitting device of this embodiment has an advantage that the temperature rise is small even when more current is passed.

<Example 4>
The difference of the present embodiment from Embodiment 1 is that a flexible material is used for the second conductive substrate. Specifically, the first adhesive and the semiconductor light emitting element are placed on the first conductive substrate. After the arrangement, the Ag layer side is bonded to the semiconductor light emitting device and the second conductive substrate made of polyimide (12.5 μm) / epoxy (10 μm) / Cu (18 μm) / Ni (5 μm) / Ag (2 μm). Bond with the agent. Other than that, it produces similarly to Example 1. FIG.
The semiconductor light emitting device of the present embodiment can also be configured as a flexible light emitting device 50 that can be bent flexibly and freely as compared with the semiconductor light emitting device of the first embodiment, for example, along a curved surface. It is also possible to arrange a light emitting device.

<Example 5>
The difference of the present embodiment from Embodiment 1 is that an auxiliary electrode is provided on the conductive film of the first conductive substrate, as shown in FIG. A pattern having a length of 5 cm and a width of 500 μm made of an Ag paste having a thickness of 20 μm is formed on the conductive substrate at equal intervals between the planned mounting positions of the semiconductor light emitting element, and then a second insulating adhesive is disposed. Other than that, it produces similarly to Example 1. FIG.
Compared with the semiconductor light emitting device of the first embodiment, the semiconductor light emitting device of this embodiment can supply a current evenly in the plane of the semiconductor light emitting device, and makes light extraction from the semiconductor light emitting device uniform. be able to.

  The semiconductor light-emitting device of the present invention can be used in a wide range of lighting fixtures, vehicle-mounted lighting, displays, indicators, and the like.

DESCRIPTION OF SYMBOLS 100 Semiconductor light-emitting device 10 Conductive substrate 11 Conductive film 12 Connection part 20 Semiconductor light-emitting element 21 Growth substrate 22 N-type semiconductor layer 23 Active layer 24 P-type semiconductor layer 25 P-side electrode 26 N-side electrode 31 First insulating adhesion Agent 32 Second Insulating Adhesive 33 Elastic Material 40 Auxiliary Electrode

Claims (10)

In a semiconductor light emitting device in which a plurality of semiconductor light emitting elements are sandwiched between a pair of substrates at least one of which has translucency,
Between the adjacent semiconductor light emitting elements, the first insulating adhesive and the second insulating adhesive are provided, and the first insulating adhesive is disposed so as to cover the side surfaces of the respective semiconductor light emitting elements. A semiconductor light emitting device in which a second insulating adhesive is disposed between the first insulating adhesives.   The semiconductor light emitting device according to claim 1, wherein the second insulating adhesive is disposed so as to contact the first insulating adhesive and includes an elastic material.   The semiconductor light emitting device according to claim 2, wherein the elastic material is a sphere having a diameter smaller than a thickness of the semiconductor light emitting element.   4. The semiconductor light emitting device according to claim 1, wherein a refractive index of the second insulating adhesive is larger than a refractive index of the first insulating adhesive. 5.   5. The semiconductor light emitting device according to claim 1, wherein a linear expansion coefficient of the second insulating adhesive is smaller than a linear expansion coefficient of the first insulating adhesive.   5. The semiconductor light emitting device according to claim 1, wherein the first insulating adhesive is a silicone resin, and the second insulating adhesive is an epoxy resin. 6.   The semiconductor light-emitting device according to claim 1, wherein at least one of the substrates is a glass substrate provided with a translucent conductive film. Placing a second insulating adhesive on the substrate;
Semi-curing the second insulating adhesive;
Disposing a first insulating adhesive including a semiconductor light emitting element on the substrate;
A semiconductor comprising: an adhesive curing step of sandwiching the semiconductor light emitting element using the substrate and a substrate different from the substrate and curing the first insulating adhesive and the second insulating adhesive Manufacturing method of light-emitting device.   The method for manufacturing a semiconductor light emitting device according to claim 8, wherein in the adhesive curing step, the first insulating adhesive and the second insulating adhesive are arranged on the substrate so as to contact each other.   10. The method of manufacturing a semiconductor light emitting device according to claim 8, further comprising a step of mixing an elastic material with the second insulating adhesive before disposing the second insulating adhesive on the substrate. 11.

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