JP2015188034A - Manufacturing method of light-emitting device, light-emitting device, and projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a light-emitting device excellent in heat dissipation, a highly reliable light-emitting device obtained by the same, and a projector.SOLUTION: The manufacturing method of a light-emitting device 100 includes: a first bonding layer forming step of filling a recess 40 of a substrate 20 with a first conductive paste 310, sintering the first conductive paste 310, and forming a first bonding layer 31; and a second bonding layer forming step of forming a second bonding layer 32 that bonds the first bonding layer 31 and a semiconductor light emitting element 10 by interposing a second conductive paste 320 between the first bonding layer 31 and the semiconductor light emitting element 10, and sintering the second conductive paste 320.

Description

  The present invention relates to a method for manufacturing a light emitting device, a light emitting device, and a projector.

  In recent years, development of semiconductor light emitting devices has been energetically performed. As specific semiconductor light-emitting elements, a semiconductor laser (Laser Diode), a super luminescent diode (hereinafter also referred to as “SLD”), an LED (Light Emitting Diode), and the like are known.

  In a light emitting device including such a semiconductor light emitting element, the semiconductor light emitting element is mounted on a support substrate such as a copper base for the purpose of efficiently radiating the heat of the semiconductor light emitting element (see, for example, Patent Document 1). ). In the light emitting device described in Patent Literature 1, the Cu substrate and the semiconductor light emitting element are bonded via a bonding layer that is a sintered body of Ag nanoparticles. According to such a bonding layer, it is considered that the thermal conductivity can be increased and the heat of the semiconductor light emitting device can be efficiently transmitted to the Cu substrate via the bonding layer.

JP 2008-31371 A

  However, in the light emitting device described in Patent Document 1, since the bonding surface of the Cu substrate is a flat surface, the contact area between the Cu substrate and the bonding layer cannot be sufficiently widened. Therefore, particularly when the amount of heat generated by the semiconductor light emitting element is large, heat transfer to the Cu substrate through the bonding layer becomes insufficient, and there is a problem that the heat radiation function of the semiconductor light emitting element cannot be fully exhibited. .

  An object of the present invention is to provide a method for manufacturing a light-emitting device having excellent heat dissipation, and a highly reliable light-emitting device and projector obtained by this manufacturing method.

Such an object is achieved by the present invention described below.
In the method for manufacturing a light emitting device of the present invention, a first bonding layer is formed by filling a first conductive paste in the concave portion of a substrate having a concave portion, and sintering the first conductive paste to form a first bonding layer. Process,
A second junction in which a second conductive paste is interposed between the first bonding layer and the semiconductor light emitting element, and the second conductive paste is sintered to bond the first bonding layer and the semiconductor light emitting element. And a second bonding layer forming step of forming a layer.

  Thus, by providing the substrate with a recess and forming the recess so as to fill the first bonding layer, the heat of the semiconductor light emitting element can be efficiently transmitted to the substrate through the bonding layer. Therefore, a light emitting device with excellent heat dissipation can be obtained.

In the method for manufacturing a light emitting device of the present invention, prior to the second bonding layer forming step, a third conductive paste is applied to the semiconductor light emitting element, and the third conductive paste is sintered to form a third bonding layer. A third bonding layer forming step of forming
In the second bonding layer forming step, the second bonding layer is preferably bonded to the third bonding layer.

  As a result, a defective area such as a void (bubble) can be reduced between the semiconductor light emitting element and the second bonding layer, and a bonding area can be secured, so that heat from the semiconductor element can be more reliably transmitted to the substrate. It becomes possible and heat dissipation improves.

The light emitting device manufacturing method of the present invention preferably includes a third bonding layer polishing step of polishing the surface of the third bonding layer prior to the second bonding layer forming step.
Thereby, the junction area of a board | substrate and a semiconductor light-emitting device is securable.

  In the method for manufacturing a light emitting device of the present invention, it is preferable that the first conductive paste, the second conductive paste, and the third conductive paste contain metal particles having a particle size of 1 nm or more and 100 nm or less. .

  Thereby, since the fusion | melting temperature of a 2nd conductive paste can be restrained low, a board | substrate and a semiconductor light-emitting element can be joined, reducing a thermal damage.

  In the method for manufacturing a light emitting device of the present invention, it is preferable that a metal layer is provided on a surface of the recess in the first bonding layer forming step.

  Thereby, the adhesiveness of a board | substrate and a 1st joining layer can be improved.

  In the method for manufacturing a light emitting device of the present invention, it is preferable that the side surface of the recess is an inclined surface that is inclined with respect to the thickness direction of the substrate.

  Thereby, it becomes easy to fill the concave portion with the first conductive paste, and for example, generation of voids can be effectively suppressed.

The method for manufacturing a light emitting device of the present invention preferably includes a first bonding layer polishing step of polishing the surface of the first bonding layer prior to the second bonding layer forming step.
Thereby, the junction area of a board | substrate and a semiconductor light-emitting device is securable.

In the method for manufacturing a light emitting device of the present invention, the concave portion includes a first portion and a second portion connected to the first portion and having a width smaller than the first portion,
In the first bonding layer forming step, it is preferable that the first conductive paste is poured into the concave portion through the first portion.

  Thereby, for example, the first conductive paste can be filled into the second portion by capillary action. By using the capillary phenomenon in this way, generation of voids in the second portion can be more effectively suppressed.

The light emitting device of the present invention is manufactured by the method for manufacturing a light emitting device of the present invention.
As a result, a light emitting device with high heat dissipation and high reliability can be obtained.

The projector of the present invention includes a light emitting device of the present invention,
A light modulation device that modulates light emitted from the light emitting device according to image information;
And a projection device that projects an image formed by the light modulation device.
Thereby, a highly reliable projector is obtained.

It is sectional drawing which shows the light-emitting device which concerns on 1st Embodiment of this invention. It is a top view which shows typically the semiconductor light-emitting device which the light-emitting device shown in FIG. 1 has. It is the sectional view on the AA line in FIG. It is sectional drawing for demonstrating the manufacturing method of the light-emitting device shown in FIG. It is sectional drawing for demonstrating the manufacturing method of the light-emitting device shown in FIG. It is sectional drawing for demonstrating the manufacturing method of the light-emitting device shown in FIG. It is a figure which shows the board | substrate which the light-emitting device concerning 2nd Embodiment of this invention has, (a) is a top view, (b) is a BB sectional drawing in (a). It is a figure which shows the board | substrate which the light-emitting device concerning 3rd Embodiment of this invention has, (a) is a top view, (b) is CC sectional view taken on the line in (a). It is a top view which shows the supply method of the 1st electroconductive paste to the recessed part of the board | substrate shown in FIG. It is the top view and sectional drawing which show the modification of the board | substrate shown in FIG. It is a block diagram which shows an example of the optical system of the projector of this invention.

  Hereinafter, a method for manufacturing a light emitting device, a light emitting device, and a projector of the present invention will be described in detail based on embodiments shown in the accompanying drawings.

1. Light Emitting Device / Method of Manufacturing Light Emitting Device <First Embodiment>
First, the light emitting device and the manufacturing method thereof according to the first embodiment will be described.

  FIG. 1 is a cross-sectional view showing a light emitting device according to a first embodiment of the present invention. FIG. 2 is a plan view schematically showing a semiconductor light emitting element included in the light emitting device shown in FIG. 3 is a cross-sectional view taken along line AA in FIG. 4 to 6 are cross-sectional views for explaining a method of manufacturing the light emitting device shown in FIG.

≪Light emitting device≫
A light-emitting device 100 illustrated in FIG. 1 includes a semiconductor light-emitting element 10, a substrate 20, and a bonding layer 30 that bonds them. Hereinafter, the semiconductor light emitting device 10, the substrate 20, and the bonding layer 30 will be sequentially described.

-Semiconductor light emitting device-
The semiconductor light emitting device 10 is an SLD (super luminescent diode). For example, the SLD can reduce speckle noise compared to a semiconductor laser and can achieve higher output than an LED. Therefore, the SLD is suitable, for example, when the light emitting device 100 is used as a light source such as a projector. It is. However, the semiconductor light emitting element 10 is not limited to the SLD, and may be, for example, a semiconductor laser or an LED.

  2 and 3, the semiconductor light emitting device 10 includes a substrate 102, a first cladding layer 104, an active layer 106, a second cladding layer 108, a contact layer 109, a first electrode 112, The second electrode 114 and the insulating part 120 are stacked.

  As the substrate 102, for example, a first conductivity type (for example, n-type) GaAs substrate or the like can be used.

  The first cladding layer 104 is formed on the substrate 102. As the first cladding layer 104, for example, an n-type InGaAlP layer can be used.

  The active layer 106 is formed on the first cladding layer 104. The active layer 106 can have, for example, a multiple quantum well (MQW) structure in which three quantum well structures each composed of an InGaP well layer and an InGaAlP barrier layer are stacked. In the present embodiment, the active layer 106 has a first side surface 131 on which the light emitting portion 11 is formed, and a second side surface 132 and a third side surface 133 that are inclined with respect to the first side surface 131.

  A part of the active layer 106 constitutes a first gain region 150, a second gain region 160, and a third gain region 170. The gain regions 150, 160, and 170 can generate light, and the light can be guided through the gain regions 150, 160, and 170 while receiving gain.

  The first gain region 150 is provided from the second side surface 132 to the third side surface 133, and is provided in parallel to the first side surface 131. The second gain region 160 is provided from the second side surface 132 to the first side surface 131, and overlaps the first gain region 150 on the second side surface 132. The third gain region 170 is provided from the third side surface 133 to the first side surface 131, and overlaps the first gain region 150 on the third side surface 133.

  In the light generated in the gain regions 150, 160, and 170, the reflectance of the first side surface 131 is lower than the reflectance of the second side surface 132 and the reflectance of the third side surface 133. Thereby, the connection part between the second gain region 160 and the first side surface 131 and the connection part between the third gain region 170 and the first side surface 131 can be the light emitting part 11. Further, the second and third side surfaces 132 and 133 can be reflective surfaces.

  The gain regions 160 and 170 are connected to the first side surface 131 while being inclined with respect to the normal line P of the first side surface 131. As a result, light generated in the gain regions 150, 160, 170 directly between the end surface of the first side surface 131 of the second gain region 160 and the end surface of the first side surface 131 of the third gain region 170 is directly Multiple reflections can be avoided. As a result, since a direct resonator cannot be configured, laser oscillation of light generated in the gain regions 150, 160, and 170 can be suppressed or prevented.

  The gain regions 150, 160, and 170 can constitute a gain region group 180. In the semiconductor light emitting device 10, one gain region group 180 is provided. The number of gain region groups 180 is not particularly limited, and may be two or more.

  The second cladding layer 108 is formed on the active layer 106. As the second cladding layer 108, for example, a second conductivity type (for example, p-type) InGaAlP layer or the like can be used. For example, the p-type second cladding layer 108, the active layer 106 not doped with impurities, and the n-type first cladding layer 104 constitute a pin diode. Each of the first cladding layer 104 and the second cladding layer 108 is a layer having a larger forbidden band width and a smaller refractive index than the active layer 106. The active layer 106 has a function of generating light and guiding it while amplifying the light. The first cladding layer 104 and the second cladding layer 108 have a function of confining injected carriers (electrons and holes) and light (a function of suppressing light leakage) with the active layer 106 interposed therebetween.

  In the semiconductor light emitting device 10, when a forward bias voltage of a pin diode is applied between the first electrode 112 and the second electrode 114 (current is injected), gain regions 150, 160, and 170 are generated in the active layer 106. In the gain regions 150, 160, and 170, recombination of electrons and holes occurs. This recombination causes light emission. With this generated light as a starting point, stimulated emission occurs in a chain, and the light intensity is amplified in the gain regions 150, 160, and 170. Then, the light whose intensity has been amplified is emitted as light L from the light emitting unit 11. That is, the semiconductor light emitting device 10 is an edge-emitting semiconductor light emitting device.

  The contact layer 109 and a part of the second cladding layer 108 constitute a columnar portion 122. The planar shape of the columnar portion 122 is the same as the planar shape of the gain regions 150, 160, and 170. That is, the planar shape of the upper surface of the contact layer 109 is the same as the planar shape of the gain regions 150, 160, and 170. For example, the current path between the first and second electrodes 112 and 114 is determined by the planar shape of the columnar section 122, and as a result, the planar shape of the gain regions 150, 160, and 170 is determined.

The insulating part 120 is provided on the second cladding layer 108 and on the side of the columnar part 122. As the insulating part 120, for example, a SiN layer, a SiO ₂ layer, a SiON layer, an Al ₂ O ₃ layer, or a polyimide layer can be used. When the above-described material is used as the insulating part 120, the current between the first and second electrodes 112 and 114 can flow through the columnar part 122 sandwiched between the insulating parts 120, avoiding the insulating part 120. The insulating part 120 has a refractive index smaller than that of the second cladding layer 108. In this case, the effective refractive index of the vertical cross section of the portion where the insulating portion 120 is formed is smaller than the effective refractive index of the vertical cross section of the portion where the insulating portion 120 is not formed, that is, the portion where the columnar portion 122 is formed. Thereby, light can be efficiently confined in the gain regions 150, 160, and 170 in the planar direction.

  The first electrode 112 is formed on the entire lower surface of the substrate 102. As the 1st electrode 112, what laminated | stacked in order of the Cr layer, the AuGe layer, Ni layer, and Au layer from the board | substrate 102 side can be used, for example.

  The second electrode 114 is formed on the contact layer 109. The planar shape of the second electrode 114 is the same as the planar shape of the gain regions 150, 160, 170, for example. As the second electrode 114, for example, a stacked layer in the order of a Cr layer, an AuZn layer, and an Au layer from the contact layer 109 side can be used.

  The semiconductor light emitting element 10 is formed by a semiconductor processing technique such as a photolithography technique and an etching technique.

  As shown in FIG. 1, the semiconductor light emitting element 10 having the above configuration is mounted on a substrate 20 in a junction-down state. That is, the semiconductor light emitting device 10 has the second electrode 114 side facing the substrate 20 so that the active layer 106 is located on the substrate 20 side of the substrate 102 of the semiconductor light emitting device 10 (up and down in the example of FIG. Implemented in reverse). Since the semiconductor light emitting element 10 is an edge emitting semiconductor light emitting element, the light L emitted from the light emitting unit 11 travels in a direction along the main surface of the substrate 20.

-Board-
The substrate 20 mainly has a function of supporting the semiconductor light emitting element 10 and a function of radiating the heat of the semiconductor light emitting element 10. Such a substrate 20 is composed of, for example, a silicon substrate. A recess 40 is formed on the upper surface of the substrate 20 (the surface on the semiconductor light emitting element 10 side). The recess 40 has a rectangular shape in plan view, a side surface 41 of which is tapered with respect to the thickness direction of the substrate 20, and a transverse area gradually decreases from the opening toward the bottom surface. That is, the recess 40 has a quadrangular pyramid shape.

  A metal film 50 formed by sputtering, vapor deposition or the like is provided on the surface of the recess 40. The metal film 50 is a film for improving the adhesion between the substrate 20 and the bonding layer 30. Therefore, by providing the metal film 50, a bonding area between the substrate 20 and the semiconductor light emitting element 10 is secured, the bonding strength is improved, and the light emitting device 100 having high mechanical strength and excellent reliability can be obtained. The constituent material of the metal film 50 is not particularly limited as long as the above effect can be exhibited. For example, various materials such as Au, Ag, Cu, Pt, Pb, Ni, Cr, W, Mo, Ti, and the like can be used. A metal material or an alloy material containing these metals can be used.

  Note that wiring that is electrically connected to the semiconductor light emitting element 10 may be formed on the substrate 20. In this case, for example, the wiring can be electrically connected to the second electrode 114 via the bonding layer 30 and can be electrically connected to the first electrode 112 via the bonding wire.

-Junction layer-
The bonding layer 30 includes a first bonding layer 31 disposed in the recess 40, a third bonding layer 33 provided on the lower surface of the semiconductor light emitting element 10, and the first bonding layer 31 and the third bonding layer 33. And a second bonding layer 32 provided (intervened) therebetween, and is constituted of these laminated bodies.

  Thus, by arranging the first bonding layer 31 in the recess 40, the contact area between the first bonding layer 31 and the substrate 20 can be increased, and the first bonding layer 31 is embedded in the substrate 20. (Embed). Therefore, more heat generated in the semiconductor light emitting element 10 can be efficiently transferred to the substrate 20 through the bonding layer 30. In particular, in the present embodiment, the recess 40 has a tapered shape, and heat is transferred radially from the first bonding layer 31 to the substrate 20, so that the heat of the semiconductor light emitting element 10 can be efficiently transferred to the substrate 20. . In addition, since the side surfaces of the second bonding layer 32 and the third bonding layer 33 are exposed in the bonding layer 30, the heat of the semiconductor light emitting element 10 can be radiated from these side surfaces. Therefore, the heat of the semiconductor light emitting element 10 can be sufficiently radiated from the substrate 20, and the heat of the semiconductor light emitting element 10 can be radiated from the bonding layer 30. As a result, the light emitting device 100 is excellent in heat dissipation.

  The first, second, and third bonding layers 31, 32, and 33 are preferably 200 W / K · m or more. Thereby, sufficiently high thermal conductivity can be imparted to the bonding layer 30, and the heat of the semiconductor light emitting element 10 can be more efficiently transferred to the substrate 20.

  Each of the first, second, and third bonding layers 31, 32, and 33 is formed by sintering a conductive paste, as will be described later in the manufacturing method.

≪Method for manufacturing light emitting device≫
Next, a method for manufacturing the light emitting device 100 will be described with reference to the drawings.

  The method for manufacturing the light emitting device 100 includes a first bonding layer forming step of filling the concave portion 40 of the substrate 20 with the first conductive paste 310 and sintering the first conductive paste 310 to form the first bonding layer 31. The first bonding layer polishing step of polishing the surface of the first bonding layer 31, the third conductive paste 330 is disposed on the lower surface of the semiconductor light emitting element 10 (on the second electrode 114), and the third conductive paste 330 is used. A third bonding layer forming step of sintering to form the third bonding layer 33; a third bonding layer polishing step of polishing the surface of the third bonding layer; and the first bonding layer 31 and the third bonding layer 33. A second bonding layer forming step in which the second conductive paste 320 is interposed therebetween and the second conductive paste 320 is sintered to form the second bonding layer 32.

[First bonding layer forming step]
First, as shown in FIG. 4A, a substrate 20 made of a silicon substrate is prepared. Next, a mask having an opening corresponding to the concave portion 40 is formed on the surface of the substrate 20, and the substrate 20 is wet-etched through the mask, whereby the concave portion 40 is formed in the substrate 20 as shown in FIG. Form. According to the wet etching, the crystal plane of silicon is exposed, so that a tapered recess 40 is naturally formed.

  Next, as shown in FIG. 4C, a metal film 50 is formed on the inner surface of the recess 40 by sputtering or vapor deposition.

  Next, as shown in FIG. 4D, the first conductive paste 310 is supplied and arranged (filled) in the recess 40. The supply of the first conductive paste 310 into the recess 40 can be performed, for example, by a dispensing method using a dispenser. By supplying the first conductive paste 310 by the dispensing method, the supplied first conductive paste 310 gradually spreads into the recess 40 due to a capillary phenomenon, so that voids (gap / bubbles with the substrate 20) are generated. Is effectively suppressed. In particular, since the concave portion 40 is tapered, when the first conductive paste 310 is supplied into the concave portion 40, the first conductive paste 310 travels along the side surface of the concave portion 40 to the bottom of the concave portion 40 smoothly. From this point, the generation of voids is effectively suppressed. However, the supply of the first conductive paste 310 into the recess 40 is not limited to the dispensing method, and may be performed, for example, by a screen printing method.

  Here, the first conductive paste 310 is not particularly limited, and for example, a paste in which metal particles 312 are dispersed in a solvent 311 can be used.

  The metal particles 312 are not particularly limited, and for example, silver particles, copper particles, and the like can be used. Further, the particle size (diameter) of the metal particles 312 is not particularly limited, but specifically, it is preferable to include particles having a size of about 1 nm or more and 100 nm or less. That is, the metal particles 312 preferably include so-called “metal nanoparticles”. As a result, the first bonding layer 31 having a low melting point and high thermal conductivity can be formed. On the other hand, examples of the solvent 311 include hydrocarbon solvents such as n-hexane, n-heptane, n-undecane and toluene, higher alcohols such as n-nonanol and n-undecanol, alcohols such as octanol and terpineol, and aqueous systems. A solvent can be used.

  Next, the first conductive paste 310 is sintered to form the first bonding layer 31 as shown in FIG.

[First bonding layer polishing step]
Next, as shown in FIG. 5A, the surface of the first bonding layer 31 is polished to remove unnecessary films such as an oxide film formed on the surface of the first bonding layer 31, and the first bonding The surface of the layer 31 is flattened. In this way, by removing unnecessary films and planarizing the surface, in the subsequent second bonding layer forming step, a bonding area between the first bonding layer 31 and the second bonding layer 32 is secured, and more It can be firmly joined. In addition, it does not specifically limit as a grinding | polishing method, For example, it can carry out by CMP (chemical mechanical polishing), plasma processing, etc.

  In the present embodiment, the upper surface of the first bonding layer 31 is flush with the upper surface of the substrate 20, but the position of the upper surface of the first bonding layer 31 is not limited to this, and the upper surface of the substrate 20. It may be located on the lower side or may be located on the upper side (that is, a part of the first bonding layer 31 may protrude from the recess 40).

[Third bonding layer forming step]
Next, as shown in FIG. 5B, a semiconductor light emitting element 10 is prepared. Next, the third conductive paste 330 is supplied and disposed on the surface of the second electrode 114 of the semiconductor light emitting device 10. The supply / arrangement of the third conductive paste 330 can be performed using, for example, a screen printing method or a dispensing method. In addition, it does not specifically limit as the 3rd conductive paste 330, For example, the same thing as the 1st conductive paste 310 can be used. Next, the third conductive paste 330 is sintered to form the third bonding layer 33 as shown in FIG.

[Third bonding layer polishing step]
Next, as shown in FIG. 5D, the surface of the third bonding layer 33 is polished to remove unnecessary films such as an oxide film formed on the surface of the third bonding layer 33, and the third bonding layer. The surface of the layer 33 is flattened. In this way, by removing unnecessary films and planarizing the surface, in the subsequent second bonding layer forming step, a bonding area between the third bonding layer 33 and the second bonding layer 32 is secured, and more It can be firmly joined. In addition, it does not specifically limit as a grinding | polishing method, For example, it can carry out by CMP (chemical mechanical polishing), plasma processing, etc.

[Second bonding layer forming step]
Next, as shown in FIG. 6A, the second conductive paste 320 is supplied and disposed on the first bonding layer 31 of the substrate 20. The second conductive paste 320 is not particularly limited, and for example, a paste obtained by dispersing metal particles 322 in a solvent 321 can be used. The metal particles 322 are not particularly limited, and silver particles, copper particles, and the like can be used. Further, the particle size (diameter) of the metal particles 322 is not particularly limited, but for example, it is preferable to include particles having a size of about 1 nm or more and 100 nm or less. That is, the metal particles 322 preferably include so-called “metal nanoparticles”. As described above, since the metal particles 322 include those having a small particle diameter, the melting point can be lowered, and the metal particles 322 are fused at a low temperature. That is, the firing temperature of the second conductive paste 320 can be lowered, and thermal damage to the semiconductor light emitting element 10 and the substrate 20 can be reduced. On the other hand, examples of the solvent 321 include hydrocarbon solvents such as n-hexane, n-heptane, n-undecane, and toluene, higher alcohols such as n-nonanol and n-undecanol, alcohols such as octanol and terpineol, and aqueous systems. A solvent can be used.

Next, as illustrated in FIG. 6B, the semiconductor light emitting element 10 is disposed on the substrate 20 such that the third bonding layer 33 is disposed on the second conductive paste 320. Next, as shown in FIG. 6C, the second conductive paste 320 is baked to form the second bonding layer 32 bonded to the first and third bonding layers 31 and 33. Thereby, the bonding layer 30 including the first, second, and third bonding layers 31, 32, and 33 is formed, and the substrate 20 and the semiconductor light emitting element 10 are bonded via the bonding layer 30.
Thus, the light emitting device 100 is obtained.

  According to such a manufacturing method, the light emitting device 100 having excellent heat dissipation can be easily manufactured.

Second Embodiment
7A and 7B are diagrams showing a substrate included in the light emitting device according to the second embodiment of the present invention, in which FIG. 7A is a plan view and FIG. 7B is a cross-sectional view taken along line BB in FIG.

  Hereinafter, the light emitting device according to the second embodiment will be described with a focus on differences from the above-described embodiment, and description of similar matters will be omitted.

  The light emitting device of the second embodiment is the same as the light emitting device of the first embodiment described above, except that the shape of the recess formed in the substrate is different. In FIG. 7, the same reference numerals are given to the same components as those in the above-described embodiment.

  As shown in FIG. 7, the side surface of the recess 40 of the present embodiment is substantially parallel to the thickness direction of the substrate 20 and is substantially orthogonal to the upper surface. On the other hand, the bottom surface of the recess 40 is an arch-shaped curved surface curved in a concave shape. With such a shape, when the first conductive paste 310 is filled in the recess 40 in the manufacturing process of the light emitting device 100, the first conductive paste 310 extends along the recess on the bottom surface of the recess 40. Since it expands inside, generation | occurrence | production of a void can be suppressed more effectively.

  Also according to the second embodiment, the same effects as those of the first embodiment described above can be exhibited.

<Third Embodiment>
8A and 8B are diagrams showing a substrate included in the light emitting device according to the third embodiment of the present invention. FIG. 8A is a plan view, and FIG. 8B is a cross-sectional view taken along the line CC in FIG. FIG. 9 is a plan view showing a method of supplying the first conductive paste to the recesses of the substrate shown in FIG. 10 is a plan view and a cross-sectional view showing a modification of the substrate shown in FIG.

  Hereinafter, the light emitting device according to the third embodiment will be described with a focus on differences from the above-described embodiments, and description of similar matters will be omitted.

  The light emitting device of the third embodiment is the same as the light emitting device of the first embodiment described above, except that the shape of the recess formed in the substrate is different. In FIG. 8, the same reference numerals are given to the same components as those in the above-described embodiment.

  As shown in FIG. 8, the recess 40 of the present embodiment is connected to the first portion 40A and the first portion 40A, and a pair of first recesses having a width W smaller than the first portion 40A and a depth of the recess. Two portions 40B. Further, the pair of second portions 40B are disposed to face each other with the first portion 40A interposed therebetween, and are connected to the first portion 40A. In the recess 40 having such a shape, the first portion 40 </ b> A functions as a supply port for supplying the first conductive paste 310.

  As shown in FIG. 9A, when the first conductive paste 310 is supplied from the first portion 40A in the manufacturing process of the light emitting device 100, it is supplied to the first portion 40A as shown in FIG. 9B. The first conductive paste 310 spreads in the second portion 40B by capillary action. According to such a method, since the first portion 40A is opened larger than the second portion 40B, the first conductive paste 310 can be easily supplied into the recess 40. Furthermore, since the first conductive paste 310 is filled into the second portion 40B by capillary action, voids are unlikely to occur in the second portion 40B.

  Also according to the third embodiment, the same effects as those of the first embodiment described above can be exhibited.

  As a modification of the present embodiment, for example, a plurality of first portions 40A may be provided as shown in FIG. In the recess 40 shown in FIG. 10, three first portions 40A are provided side by side, and these are connected by two second portions 40B. The central first portion 40A is configured to be smaller than the width of the first portion 40A provided at the end. In this case, the first conductive paste 310 may be supplied from each of the three first portions 40A. As a result, the second conductive portion 310 is filled with the first conductive paste 310 from both ends thereof, so that the second conductive portion 310 can be filled efficiently and in a short time. Can do.

2. Next, the projector of the present invention will be described. However, the configuration shown below is an example, and the configuration of the projector of the present invention is not limited to the following configuration.

  As shown in FIG. 11, the projector 500 includes a red light source 100R, a green light source 100G, and a blue light source 100B that emit red light, green light, and blue light. The light emitting device 100 described above can be used as the light sources 100R, 100G, and 100B.

  The projector 500 further includes lens arrays 502R, 502G, and 502B, transmissive liquid crystal light valves (light modulation devices) 504R, 504G, and 504B, and a projection lens (projection device) 508.

  Light emitted from the light sources 100R, 100G, and 100B is incident on the lens arrays 502R, 502G, and 502B. For example, the incident surfaces of the lens arrays 502R, 502G, and 502B are inclined at a predetermined angle with respect to the optical axis of the light emitted from the light sources 100R, 100G, and 100B. Thereby, the optical axis of the light emitted from the light sources 100R, 100G, and 100B can be converted. Therefore, for example, the light emitted from the light sources 100R, 100G, and 100B can be orthogonal to the irradiation surface of the liquid crystal light valve 504. In particular, as shown in FIG. 2, when the gain regions 160 and 170 of the semiconductor light emitting element 10 are provided to be inclined with respect to the first side surface 131, the light emitted from the light emitting device 100 Since the lens array 502R, 502G, 502B is incident on the perpendicular line P, it is desirable that the incident surfaces of the lens arrays 502R, 502G, 502B are inclined at a predetermined angle.

  The lens arrays 502R, 502G, and 502B have convex curved surfaces on the liquid crystal light valves 504R, 504G, and 504B sides. As a result, the light whose optical axis has been converted on the incident surfaces of the lens arrays 502R, 502G, and 502B is condensed by the convex curved surface (or the diffusion angle can be reduced). Therefore, the liquid crystal light valves 504R, 504G, and 504B can be irradiated with good uniformity. As described above, the lens arrays 502R, 502G, and 502B can control the optical axis of the light emitted from the light sources 100R, 100G, and 100B to collect the light.

  The light condensed by the lens arrays 502R, 502G, and 502B is incident on the liquid crystal light valves 504R, 504G, and 504B. Each of the liquid crystal light valves 504R, 504G, and 504B modulates the incident light according to image information.

  The three color lights modulated by the liquid crystal light valves 504R, 504G, and 504B are incident on the cross dichroic prism 506. For example, the cross dichroic prism 506 is formed by bonding four right-angle prisms, and a dielectric multilayer film that reflects red light and a dielectric multilayer film that reflects blue light are arranged in a cross shape on the inner surface thereof. . Three color lights are synthesized by these dielectric multilayer films.

The light synthesized by the cross dichroic prism 506 enters a projection lens 508 that is a projection optical system. The projection lens 508 enlarges and projects the image formed by the liquid crystal light valves 504R, 504G, and 504B onto the screen (display surface) 510. As a result, a desired image is displayed on the screen 510.
The projector 500 has been described above.

  In the above example, a transmissive liquid crystal light valve is used as the light modulation device. However, a light valve other than liquid crystal may be used, or a reflective light valve may be used. Examples of such a light valve include a reflection type liquid crystal light valve and a digital micromirror device (Digital Micromirror Device). Further, the configuration of the projection optical system is appropriately changed depending on the type of light valve used.

  Further, the scanning type image having a scanning unit that is an image forming apparatus that displays an image of a desired size on the display surface by causing the light sources 100R, 100G, and 100B to scan light from the light source on the screen. The present invention can also be applied to a light source device of a display device (projector).

  As mentioned above, although the manufacturing method of the light-emitting device, the light-emitting device, and the projector of this invention were demonstrated based on embodiment of illustration, this invention is not limited to this, The structure of each part has the same function. Any configuration can be substituted. In addition, any other component may be added to the present invention. Moreover, you may combine each embodiment mentioned above suitably.

  In the above-described embodiment, the third bonding layer is formed in the semiconductor light emitting device, but the third bonding layer may be omitted. In this case, the second bonding layer and the semiconductor light emitting element may be bonded.

  In the above-described embodiment, the first bonding layer polishing step and the third bonding layer polishing step are included. However, these steps may be performed as necessary and may be omitted.

  DESCRIPTION OF SYMBOLS 100 ... Light-emitting device 100B ... Blue light source 100G ... Green light source 100R ... Red light source 10 ... Semiconductor light-emitting device 102 ... Substrate 104 ... First clad layer 106 ... Active layer 108 ... Second clad layer 109 …… Contact layer 11 …… Light emitting portion 112 …… First electrode 114 …… Second electrode 120 ...... Insulating portion 122 …… Columnar portion 131 …… First side surface 132 …… Second side surface 133 …… Third side surface 150 …… First gain region 160 …… Second gain region 170 …… Third gain region 180 …… Gain region group 20 …… Substrate 30 …… Junction layer 31 …… First junction layer 310 …… First conductivity Paste 311 …… Solvent 312 …… Metal particles 32 …… Second bonding layer 320 …… Second conductive paste 321 …… Solvent 322 …… Metal particles 33 …… Third bonding layer 330 …… Third conductive paste 40 …… Concavity 40A …… First part 40B …… Second part 41 …… Side 50 …… Metal film 500 …… Projector 502R, 502G, 502B …… Lens array 504, 504R, 504G, 504B ... Liquid crystal light valve 506 ... Cross dichroic prism 508 ... Projection lens 510 ... Screen L ... Light P ... Perpendicular W ... Width

Claims (10)

A first bonding layer forming step of filling the concave portion of the substrate having the concave portion with a first conductive paste and sintering the first conductive paste to form a first bonding layer;
A second junction in which a second conductive paste is interposed between the first bonding layer and the semiconductor light emitting element, and the second conductive paste is sintered to bond the first bonding layer and the semiconductor light emitting element. And a second bonding layer forming step of forming a layer. Prior to the second bonding layer forming step, a third bonding layer forming step of applying a third conductive paste to the semiconductor light emitting element and sintering the third conductive paste to form a third bonding layer. Have
2. The method for manufacturing a light emitting device according to claim 1, wherein in the second bonding layer forming step, the second bonding layer is bonded to the third bonding layer.   3. The method for manufacturing a light emitting device according to claim 2, further comprising a third bonding layer polishing step of polishing a surface of the third bonding layer prior to the second bonding layer forming step.   4. The light emitting device according to claim 2, wherein the first conductive paste, the second conductive paste, and the third conductive paste include metal particles having a particle size of 1 nm or more and 100 nm or less. Method.   5. The method for manufacturing a light emitting device according to claim 1, wherein, in the first bonding layer forming step, a metal layer is provided on a surface of the concave portion.   6. The method for manufacturing a light emitting device according to claim 1, wherein a side surface of the concave portion is an inclined surface that is inclined with respect to a thickness direction of the substrate.   The method for manufacturing a light emitting device according to claim 1, further comprising a first bonding layer polishing step of polishing a surface of the first bonding layer prior to the second bonding layer forming step. . The recess has a first part and a second part connected to the first part and having a width smaller than the first part,
8. The method for manufacturing a light emitting device according to claim 1, wherein in the first bonding layer forming step, the first conductive paste is poured into the recess through the first portion. 9.   A light-emitting device manufactured by the method for manufacturing a light-emitting device according to claim 1. A light emitting device according to claim 9;
A light modulation device that modulates light emitted from the light emitting device according to image information;
A projector for projecting an image formed by the light modulation device.

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