JP2014107502A - Light emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light emitting device which achieves high luminous efficiency.SOLUTION: A light emitting device 1 comprises: a semiconductor light emitting element 10; a window plate member 20 which may transmit light radiated from the semiconductor light emitting element 10 and on which the semiconductor light emitting element 10 is mounted in a flip chip manner; a cooling solution 30 for cooling the semiconductor light emitting element 10; a sealing container 22 which seals the cooling solution 30 therein in cooperation with the window plate member 20; and electrodes 41, 42 for packaging which are provided on one surface of the sealing container 22 which is different from a surface on which the window plate member 20 is disposed.

Description

  The present invention relates to a light emitting device. More particularly, the present invention relates to a light emitting device having a semiconductor light emitting element.

  As display devices and lighting devices, light-emitting devices that use light-emitting diodes (LEDs), which are semiconductor light-emitting elements, as light-emitting elements are widely used. A light emitting device having a light emitting diode is formed by sealing the light emitting diode with a transparent resin mold. The sealed light emitting diode is mounted on a printed circuit board by wire bonding or flip chip mounting.

  Patent Document 1 describes a technique in which a plurality of light emitting elements are sealed with a capsule material such as transparent or translucent silicone, and a reflective coating is applied to the outer surface of the capsule member. In the technique described in Patent Document 1, light emitted from a plurality of light emitting elements can be uniformly mixed by randomly reflecting light emitted from the plurality of light emitting elements by a reflective coating.

  However, if the power consumption of the light emitting diode is increased to increase the luminous flux of light emitted from the light emitting diode, the amount of heat generated from the light emitting diode may exceed the amount of heat released from the resin mold. . Further, it is known that, in the light emitting diode, when the temperature of the light emitting diode rises, the total luminous flux of light emitted from the light emitting diode is lowered, and the light emission efficiency of the light emitting diode is lowered. In order to solve such a problem, as a sealing member for sealing the light emitting diode, it has been studied to employ a member having higher heat dissipation characteristics than a resin mold.

  Patent Documents 2 and 3 describe techniques that employ a liquid as a sealing member of a semiconductor light emitting device. The light emitting diode package described in Patent Document 2 uses a liquid refrigerant as a sealing member of a light emitting diode chip. In the light emitting diode package described in Patent Document 2, the sapphire substrate on which the light emitting element layers are stacked is arranged so as to face the window plate member. On the other hand, the LED array head described in Patent Document 3 uses an insulating liquid substance as a sealing member of an LED chip. In the LED array head described in Patent Document 3, the LED chip is flip-chip mounted on a transparent substrate by solder bumps and sealed with a sealing material together with a liquid substance.

JP 2006-121083 A Japanese Patent Laid-Open No. 2008-4689 Japanese Utility Model Publication No. 7-21329

  In the light emitting diode package described in Patent Document 2, the light emitting diode chip is arranged such that a sapphire substrate that emits a relatively small amount of light faces a window plate member to which light is irradiated to the outside. For this reason, in the light emitting diode package described in Patent Document 2, the light emitting efficiency of the light emitting diode package is lowered.

  On the other hand, in the LED array head described in Patent Document 3, the light emitting portion of the LED chip is mounted so as to face a transparent substrate that is irradiated with light to the outside of the LED array head, but the liquid substance is a sealing material. Sealed. In general, since the sealing material has a low reflectance, the LED array head described in Patent Document 3 does not irradiate most of the light emitted from the LED chip to the side surface and the back surface. For this reason, it is not easy to increase the light emission efficiency of the LED array head described in Patent Document 3.

  Further, since the LED array head described in Patent Document 3 is assumed to be used in an LED printer, a part of light emitted from the light emitting unit is emitted from the transparent substrate through the spacer and the lens. Is. In the LED array head described in Patent Document 3, since light is not irradiated from the entire surface of the transparent substrate, it is not easy to increase the light emission efficiency.

  Accordingly, an object of the present invention is to provide a light emitting device having a high light emission efficiency in a light emitting device having a semiconductor light emitting element.

  To achieve the above object, a light-emitting device according to the present invention includes a semiconductor light-emitting element, a window plate member that is capable of transmitting light emitted from the semiconductor light-emitting element, and on which the semiconductor light-emitting element is flip-chip mounted, A cooling solution for cooling the semiconductor light emitting element, a sealing container that seals the cooling solution together with the window plate member, and a sealing container that is different from the surface on which the window plate member is disposed And an electrode for mounting provided on the surface.

  Furthermore, in the light emitting device according to the present invention, the sealing container material forming the sealing container preferably includes aluminum, or copper plated with aluminum or silver.

  The inner surface of the sealing container material is formed of aluminum or silver having a high reflectance, so that the light irradiated from the semiconductor light emitting element is reflected and irradiated to the outside of the semiconductor light emitting element through the window plate member. Therefore, the light emission efficiency of the light emitting device can be improved.

  Further, since the sealing container material contains aluminum or copper having a high thermal conductivity, heat generated from the semiconductor light emitting element is dissipated through a heat conduction path formed by the cooling solution, the sealing container, and the mounting substrate. Therefore, the heat dissipation characteristics of the light emitting device are improved. By improving the heat dissipation characteristics of the light emitting device, the light emission efficiency of the light emitting device can be further improved.

  Furthermore, in the light emitting device according to the present invention, it is preferable that an uneven portion is formed on the inner surface of the sealing container.

  Furthermore, in the light emitting device according to the present invention, it is preferable that the concavo-convex portion convects the cooling solution.

  By forming an uneven portion on the inner surface of the sealing container, the cooling solution can be agitated randomly. The heat dissipation characteristics of the light emitting device can be further improved by randomly stirring the cooling solution.

  Furthermore, in the light emitting device according to the present invention, it is preferable that the uneven portion has a Fresnel lens shape.

  The uneven part is formed on the surface facing the window plate member of the sealing container, and by having a Fresnel lens-like shape, most of the reflected light of the light irradiated from the semiconductor light emitting element to the opposite side of the window plate member, It is possible to directly irradiate the outside of the semiconductor light emitting device.

  The uneven portion is formed on the surface of the window plate member on which the semiconductor light emitting element is mounted and has a Fresnel lens shape, whereby the light incident on the uneven portion can be refracted and irradiated in a desired direction.

  According to the light emitting device of the present invention, it is possible to irradiate much of the light emitted from the semiconductor light emitting element to the outside of the semiconductor light emitting element, so that the light emission efficiency of the light emitting device can be improved.

  In addition, according to the light emitting device of the present invention, the heat of the semiconductor light emitting element can be dissipated through the heat conduction path formed by the cooling solution, the sealing container, and the mounting substrate, thereby further improving the light emission efficiency of the light emitting device. It became possible.

(A) is a figure which shows roughly the relationship between the temperature of a light emitting diode, and the total luminous flux of the light irradiated from a light emitting diode, (b) is the electric current applied to a light emitting diode, and is irradiated from a light emitting diode. It is a figure which shows roughly the relationship with the total luminous flux of the light to be. It is a perspective view of an example of a light-emitting device. FIG. 3 is a cross-sectional view of one cross section of the light emitting device shown in FIG. 2. It is sectional drawing of the other cross section of the light-emitting device shown in FIG. (A) is a figure which shows the light emission state of the light-emitting device shown in FIG. 2, (b) is a figure which shows the thermal radiation state of the light-emitting device shown in FIG. (A) is sectional drawing of the cross section of the other example of a light-emitting device, (b) is sectional drawing of the other cross section of the light-emitting device shown to (a). (A) is a figure which shows the light emission state of the light-emitting device shown in FIG. 6, (b) is a figure which shows the thermal radiation state of the light-emitting device shown in FIG. (A) is sectional drawing of the cross section of the other example of a light-emitting device, (b) is sectional drawing of the other cross section of the light-emitting device shown to (a). (A) is a figure which shows the light emission state of the light-emitting device shown in FIG. 8, (b) is a figure which shows the thermal radiation state of the light-emitting device shown in FIG. It is sectional drawing of the cross section of the other example of a light-emitting device. It is sectional drawing of the cross section of the other example of a light-emitting device.

  Hereinafter, a light emitting device according to the present invention will be described with reference to the drawings. However, it should be noted that the technical scope of the present invention is not limited to these embodiments, and extends to equivalents to the invention described in the claims.

  FIG. 1A is a diagram schematically showing the relationship between the temperature of a light emitting diode to which a constant current is applied and the total luminous flux of light emitted from the light emitting diode, and FIG. It is a figure which shows roughly the relationship between the electric current and the total luminous flux of the light irradiated from a light emitting diode. In FIG. 1B, the broken line is a curve showing the characteristics of the conventional light emitting device, and the solid line is a curve showing the characteristics of the light emitting device having good heat dissipation characteristics.

  As shown in FIG. 1A, the total luminous flux of light emitted from the light emitting diode gradually decreases as the temperature of the light emitting diode increases even when a current having a constant current value is applied to the light emitting diode. . There are two factors that cause the temperature of the light emitting diode to rise: an external factor and an internal factor. The external factor is a factor such as an environmental temperature around the light emitting diode. The internal factor is a factor such as a temperature rise caused by increasing the current value of the current applied to the light emitting diode.

  When the temperature of the light emitting diode rises, the total luminous flux of light emitted from the light emitting diode decreases. In order to maintain the total luminous flux of the light emitted from the light emitting diode when the temperature of the light emitting diode rises, it is required to increase the current value of the current applied to the light emitting diode. However, as indicated by the above internal factors, the temperature of the light emitting diode increases as the current value of the current applied to the light emitting diode increases. When the current value of the current applied to the light emitting diode increases and the temperature of the light emitting diode rises, the total luminous flux of light emitted from the light emitting diode with the same current value decreases.

  The luminous efficiency of the light emitting diode is indicated by the ratio between the total luminous flux of light emitted from the light emitting diode and the power consumption consumed by the light emitting diode. For this reason, if the current value applied to the light emitting diode is increased in order to maintain the total luminous flux of the light emitted from the light emitting diode, the light emission efficiency of the light emitting diode will be reduced.

  By improving the heat dissipation characteristics of the light emitting diode, the temperature rise of the light emitting diode when the same current value is applied can be suppressed, and the light emission efficiency of the light emitting diode can be prevented from decreasing. That is, by improving the heat dissipation characteristics of the light emitting diode, the light emitted from the light emitting diode is applied when a current having the same current value is applied to the light emitting diode as indicated by an arrow a in FIG. The total luminous flux will increase. Further, by improving the heat dissipation characteristics of the light emitting diode, the current value of the current applied to the light emitting diode is reduced in order to obtain the same total luminous flux as indicated by the arrow b in FIG.

  Accordingly, an object of the present invention is to provide a light emitting device with high light emission efficiency by improving the heat dissipation characteristics of a light emitting diode mounted on the light emission efficiency.

  2 is a perspective view of the light emitting device 1, FIG. 3 is a vertical sectional view of the light emitting device 1 taken along the line AA ′, and FIG. 4 is a sectional view taken along the line BB ′ of the light emitting device 1.

  The light emitting device 1 includes a light emitting diode 10, a bump 15, a window plate member 20, a sealing container 22, a cooling solution 30, and a power feeding unit 40, and is mounted on the mounting substrate 100.

  The light emitting diode 10 includes a substrate 11 that is a sapphire substrate and a semiconductor layer 13 formed on the substrate 11. The semiconductor layer 13 includes an n-type semiconductor layer, a light emitting layer, and a p-type semiconductor layer, and is formed on one surface of the substrate 11. The semiconductor layer 13 starts to emit light when a voltage equal to or higher than a predetermined threshold voltage is applied via the bump 15.

  The light emitting diode 10 irradiates light in all directions of the upward direction, the side surface direction, and the downward direction. Since the light beam irradiated downward from the light emitting diode 10 is irradiated through the substrate 11, it becomes smaller than the light beam irradiated from the light emitting diode 10 in the other direction. Further, the light irradiated downward from the light emitting diode 10 is refracted at the interface between the substrate 11 and the cooling solution 30 at a refractive index defined by the magnetic permeability and dielectric constant of the substrate 11 and the cooling solution 30.

  The bump 15 is a joining member formed of gold, and joins the light emitting diode 10 and the window plate member 20 and supplies power to the semiconductor layer 13 of the light emitting diode 10. The bump 15 is disposed so as to face the substrate 11 with the semiconductor layer 13 interposed therebetween.

  The window plate member 20 is a rectangular plate surface member made of glass having an electrode made of ITO (Indium Tin Oxide). The window plate member 20 directly transmits light emitted upward from the semiconductor layer 13 of the light emitting diode and transmits reflected light of light emitted from the semiconductor layer 13 of the light emitting diode in the other direction.

  The sealing container 22 is made of aluminum, has four side wall portions 22a to 22d, and a bottom surface portion 22e, and seals the cooling solution 30 in cooperation with the window plate member 20. Each of the four side wall portions 22a to 22d of the sealing container 22 is a rectangular wall portion, and the side sides of the side wall portions 22a to 22d are perpendicular to the side sides of the adjacent side wall portions 22a to 22d. Arranged so as to touch each other. The bottom surface portion 22e is a rectangular wall portion, and is disposed so as to be in contact with the bottom sides of the four side wall portions 22a to 22d at right angles. The sealing container 22 is press-molded using a mold having a corresponding shape.

  The sides facing the bottom sides of the four side wall portions 22a to 22d of the sealing container 22 that are in contact with the bottom sides 22e are respectively connected to end portions of the surface of the window plate member 20 on which the light emitting diodes 10 are mounted via unshown bonding members. Are joined. The joining member is selected so that the joining portion between the side wall portions 22a to 22d and the window plate member 20 is firmly joined.

  The cooling solution 30 is sealed by the window plate member 20 and the sealing container 22, and is a liquid cooling that conducts heat generated by the light emitting diode 10 to the side wall portions 22 a to 22 d and the bottom surface portion 22 e of the sealing container 22. It is a medium. The cooling solution 30 is a fluorine-based inert liquid. The fluorine-based inert liquid is an insulator and is an inert liquid with respect to the material forming the light emitting diode 10 and the bump 15.

  The power feeding unit 40 includes electrodes 41 and 42 and wirings 43 to 46. Each of the electrodes 41 and 42 is a mounting electrode provided on the bottom surface opposite to the window plate member and connected to a power supply unit (not shown) formed on the mounting substrate 100. Each of the wirings 43 and 44 has a conductive portion made of copper and an outer skin portion formed of an insulator disposed around the conductive portion. The wirings 43 and 44 are respectively disposed on the outer surfaces of the side wall portions 22c and 22a of the sealing container 22, and one end is connected to the electrodes 41 and 42, and the other end is connected to the wirings 45 and 46, respectively. Each of the wirings 45 and 46 is made of ITO, and is disposed on the surface of the window plate member 20 opposite to the surface on which the light emitting diode 10 is mounted. One end of each of the wirings 45 and 46 is connected to the wirings 43 and 44, respectively, and the other end is connected to the bump 15 via a hole and an electrode formed in the window plate member 20.

  The mounting substrate 100 is a glass composite substrate on which a conductive pattern for mounting the light emitting diode 10 and other electronic components (not shown) is formed.

  FIG. 5A is a diagram illustrating a light emission state of the light emitting device 1. In FIG. 5A, a broken line arrow indicates a path of light emitted from the light emitting diode 10 of the light emitting device 1. In FIG. 5A, the power supply unit 40 is omitted for the sake of simplicity.

  The upper surface of the semiconductor layer 13 of the light emitting diode 10 faces the window plate member 20 that transmits light through the bumps 15. For this reason, the light irradiated from the upper surface of the semiconductor layer 13 of the light emitting diode 10 is directly irradiated to the outside of the light emitting device 1 from the window plate member 20.

  On the other hand, the lower surface of the semiconductor layer 13 of the light emitting diode 10 is in contact with the substrate 11 over the entire surface. For this reason, the light beam emitted from the lower surface of the semiconductor layer 13 of the light emitting diode 10 becomes smaller than the light beam emitted from the upper window plate member 20 of the semiconductor layer 13 of the light emitting diode 10. The light irradiated from the lower surface of the semiconductor layer 13 of the light emitting diode 10 reflects the inner surface of the sealing container 22 and is irradiated from the window plate member 20 to the outside of the light emitting device 1. Therefore, in the light emitting device 1, much of the light emitted from the semiconductor layer 13 of the light emitting diode 10 can be emitted from the window plate member 20 to the outside of the light emitting device 1.

  FIG. 5B is a diagram illustrating a heat dissipation state of the light emitting device 1. In FIG. 5B, a broken line arrow indicates a conduction path of heat irradiated from the light emitting diode 10 of the light emitting device 1. In FIG. 5B, the power feeding unit 40 is omitted for the sake of simplicity.

  A first conduction path of heat generated in the light emitting diode 10 is a path that reaches the mounting substrate 100 via the bumps 15, the window plate member 20, and the side wall portions 22 a to 22 d of the sealing container 22. The second conduction path of the heat generated in the light emitting diode 10 is a path that reaches the mounting substrate 100 through the cooling solution 30 and the side wall portions 22a to 22d or the bottom surface portion 22e of the sealing container 22.

  When the light emitting diode 10 is generating heat, a temperature difference is generated between the temperature of the cooling solution 30 located near the light emitting diode 10 and the temperature of the cooling solution 30 located near the sealed container 22. For this reason, the cooling solution 30 convects inside the sealed container 22, and the heat dissipation effect through the second conduction path of the heat generated in the light emitting diode 10 is improved.

  6A is a vertical cross-sectional view of the light-emitting device 2, and FIG. 6B is a cross-sectional view taken along the line CC 'of the light-emitting device 2 shown in FIG. 6A. 6A and 6B, the power feeding unit 40 is omitted for the sake of simplicity.

  The light emitting device 2 is different from the light emitting device 1 described with reference to FIGS. 2 to 5 in that the uneven portion 50 is formed on the inner surface of the bottom surface portion 22 e of the sealing container 22.

  The concavo-convex portion 50 is made of aluminum and is integrally formed with other portions of the sealing container 22. The concavo-convex portion 50 has a concave Fresnel lens shape, and is formed so that the inclined surface faces the light emitting diode 10. The cross-section of the concavo-convex portion 50 has a shape in which substantially right-angled triangular shapes that are arranged so that the slope faces toward the light emitting diode 10 are continuously arranged. Moreover, when the uneven | corrugated | grooved part 50 is seen from the direction of the light emitting diode 10, it becomes a shape where the several concentric circle is arrange | positioned.

  When the uneven portion 50 has a concave Fresnel lens shape, when the light emitted from the light emitting diode 10 is directly incident, the incident light is reflected in a direction substantially perpendicular to the plane of the window plate member 20. it can.

  FIG. 7A is a diagram illustrating a light emission state of the light emitting device 2. In FIG. 7A, a broken line arrow indicates a path of light emitted from the light emitting diode 10 of the light emitting device 2. In FIG. 7A, the power supply unit 40 is omitted for the sake of simplicity.

  Light irradiated from the upper surface of the semiconductor layer 13 of the light emitting diode 10 is directly irradiated to the outside of the light emitting device 2 from the window plate member 20.

  On the other hand, the light emitted from the lower surface of the semiconductor layer 13 of the light emitting diode 10 enters the concavo-convex portion 50, is reflected in a direction substantially perpendicular to the plane of the window plate member 20, and is emitted from the window plate member 20 to the light emitting device 2. Can be irradiated to the outside. In the light emitting device 2, the window plate is not reflected again on the inner wall of the sealing container 22 such as the side walls 22 a to 22 d of the sealing container 22, without much of the light irradiated from the lower surface of the semiconductor layer 13 of the light emitting diode 10. It is possible to irradiate the light emitting device 2 from the member 20.

  FIG. 7B is a diagram illustrating a heat dissipation state of the light emitting device 2. In FIG. 7B, a broken line arrow indicates a conduction path of heat irradiated from the light emitting diode 10 of the light emitting device 2, and a solid line arrow indicates a direction in which the cooling solution 30 convects. In FIG. 7B, the power feeding unit 40 is omitted for the sake of simplicity.

  The heat conduction path generated in the light emitting diode 10 of the light emitting device 2 is the same as the heat conduction path generated in the light emitting diode 10 of the light emitting device 1 described with reference to FIGS. That is, the first conduction path is a path through the bump 15, the window plate member 20, and the side wall portions 22 a to 22 d of the sealing container 22, and the second conduction path is the side wall of the cooling solution 30 and the sealing container 22. This is a path through the portions 22a to 22d or the bottom surface portion 22e.

  When the light emitting diode 10 is generating heat, the cooling solution 30 convects inside the sealed container 22. In the light emitting device 2, the convection cooling solution 30 collides with the concavo-convex portion 50, the convection direction changes randomly, and turbulence occurs. Thereby, in the light-emitting device 2, the stirring effect of the cooling solution 30 inside the sealing container 22 is improved, and the heat dissipation effect via the second conduction path of the heat generated in the light-emitting diode 10 is further improved.

  With reference to FIG. 8 and 9, the light-emitting device 3 which is another example of a light-emitting device is demonstrated.

  8A is a vertical cross-sectional view of the light-emitting device 3, and FIG. 8B is a cross-sectional view along the line DD ′ of the light-emitting device 3 shown in FIG. 8A. 8A and 8B, the power feeding unit 40 is omitted for the sake of simplicity.

  The light emitting device 3 is different from the light emitting device 1 described with reference to FIGS. 2 to 5 in that the uneven portion 52 is formed on the surface of the window plate member 20 on which the light emitting diode 10 is mounted.

  The concavo-convex portion 52 is made of glass and is integrally formed with other portions of the window plate member 20. The concavo-convex portion 52 has a convex Fresnel lens shape, and is formed so that the inclined surface faces in a direction opposite to the light emitting diode 10. The cross section of the concavo-convex portion 52 has a shape in which right-angled triangles arranged so that the slope faces in the direction opposite to the light emitting diode 10 are continuously arranged. Moreover, when the uneven | corrugated | grooved part 52 is seen from the bottom face part 22e direction of the sealing container 22, it will become a shape by which the several concentric circle is arrange | positioned around the light emitting diode 10 arrange | positioned at the center part.

  FIG. 9A is a diagram illustrating a light emission state of the light emitting device 2. In FIG. 9A, a broken line arrow indicates a path of light emitted from the light emitting diode 10 of the light emitting device 3. 9A and 9B, the power supply unit 40 is omitted for the sake of simplicity.

  Light irradiated from the upper surface of the semiconductor layer 13 of the light emitting diode 10 is directly irradiated to the outside of the light emitting device 2 from the window plate member 20.

  On the other hand, most of the light emitted from the lower surface of the semiconductor layer 13 of the light emitting diode 10 is reflected by the bottom surface portions 22 e and 22 a to 22 d of the sealing container 22 and enters the concavo-convex portion 52. The light incident on the concavo-convex portion 52 is refracted by the concavo-convex portion 52 and is irradiated in a direction substantially perpendicular to the plane of the window plate member 20.

  Since the uneven portion 52 has a convex Fresnel lens shape, light traveling in a substantially vertical direction when light traveling from the side wall portions 22a to 22d of the sealing container 22 toward the light emitting diode 10 enters the uneven portion 52. Is emitted from the window plate member 20 to the outside of the light emitting diode. That is, the concavo-convex portion 52 refracts light from the side wall portions 22 a to 22 d of the sealing container 22 toward the light emitting diode 10 in a direction substantially perpendicular to the window plate member 20. For example, when light irradiated from the lower surface of the light emitting diode 10 is reflected by the bottom surface portion 22e and the side wall portions 22a to 22d of the sealing container 22 and then enters the concavo-convex portion 52, the direction substantially perpendicular to the window plate member 20 The light that travels to is emitted from the window plate member 20 to the outside of the light emitting diode. Further, the concavo-convex portion 52 transmits not only light traveling from the side wall portions 22a to 22d of the sealing container 22 toward the light emitting diode 10 but also light traveling from the peripheral portion of the bottom surface portion 22e of the sealing container 22 toward the light emitting diode 10. Can irradiate outside.

  FIG. 9B is a diagram illustrating a heat dissipation state of the light emitting device 3. In FIG. 9B, a broken line arrow indicates a conduction path of heat irradiated from the light emitting diode 10 of the light emitting device 3, and a solid line arrow indicates a direction in which the cooling solution 30 convects.

  The heat conduction path generated in the light emitting diode 10 of the light emitting device 3 is the same as the heat conduction path generated in the light emitting diode 10 of the light emitting device 1 described with reference to FIGS. That is, the first conduction path is a path through the bump 15, the window plate member 20, and the side wall portions 22 a to 22 d of the sealing container 22, and the second conduction path is the side wall of the cooling solution 30 and the sealing container 22. This is a path through the portions 22a to 22d or the bottom surface portion 22e.

  When the light emitting diode 10 is generating heat, the cooling solution 30 convects inside the sealed container 22. In the light emitting device 3, the convection cooling solution 30 collides with the concavo-convex portion 52, the convection direction changes randomly, and turbulence occurs. Thereby, in the light-emitting device 3, the stirring effect of the cooling solution 30 inside the sealing container 22 is improved, and the heat dissipation effect through the second conduction path of the heat generated in the light-emitting diode 10 is further improved.

  Since the light emitting devices 1 to 3 are joined to the window plate member 20 by the joining member disposed so that the light emitting diode 10 faces the substrate 11 through the semiconductor layer 13, the light emitted from the surface with high light emission efficiency. Can be directly irradiated to the outside of the light emitting devices 1 to 3. In addition, most of the light emitted from the lower surface of the semiconductor layer 13 through the substrate 11 can be reflected from the inner surface of the sealing container 22 and irradiated outside the light emitting devices 1 to 3. Therefore, the light emitting devices 1 to 3 can improve the light emission efficiency.

  In the light emitting devices 1 to 3, the heat generated in the light emitting diode 10 is radiated through the cooling solution 30 and the conductive path reaching the mounting substrate 100 through the side wall portions 22 a to 22 d or the bottom surface portion 22 e of the sealing container 22. Therefore, the temperature rise of the light emitting diode 10 can be suppressed. For this reason, the light-emitting devices 1 to 3 can further improve the light emission efficiency.

  Since the light-emitting device 2 has the uneven portion 50, a large amount of reflected light that is irradiated from the lower surface of the semiconductor layer 13 through the substrate 11 and enters the uneven portion 50 is further reflected on the surface, The light can be irradiated to the outside of the light emitting device 2 through the window plate member 20.

  Moreover, since the light-emitting device 2 has the uneven part 50, the heat dissipation characteristics of the light-emitting device 2 can be further improved by randomly stirring the cooling solution 30.

  Since the light emitting device 3 has the uneven portion 52, the light incident on the uneven portion 52 can be refracted and irradiated in a desired direction.

  Moreover, since the light-emitting device 3 has the concavo-convex portion 52, the heat dissipation characteristics of the light-emitting device 3 can be further improved by randomly stirring the cooling solution 30.

  The light emitting diodes 10 of the light emitting devices 1 to 3 are disposed at a substantially central portion of the window plate member 20, but may be disposed at any position within the plane of the window plate member 20. Moreover, although the single light emitting diode 10 is each mounted in the light-emitting devices 1-3, you may mount a some light emitting diode. For example, the light emitting device may include three light emitting diodes: a first diode that emits red light, a second diode that emits green light, and a third diode that emits blue light.

  Moreover, although the board | substrate 11 of the light emitting diode 10 of the light-emitting devices 1-3 is a sapphire substrate, it is good also as a board | substrate formed with the other material which permeate | transmits light.

  In addition, the bump 15 that joins between the light emitting diode 10 and the window plate member 20 of the light emitting devices 1 to 3 is a joining member formed of gold, but other metals such as copper and nickel, or gold, copper and It is good also as a joining member formed with the alloy containing metals, such as nickel. Further, instead of the bumps 15, other coupling members such as conductive paste may be employed.

  Further, the window plate member 20 of the light emitting devices 1 to 3 is a plate surface member made of glass having ITO, but is made of a material that transmits light and does not cause deformation and deterioration due to heat generation of the light emitting diode 10. A plate surface member may be used.

  Moreover, although the sealing container 22 of the light emitting devices 1 to 3 is made of aluminum, the thermal conductivity is 50 [W / m · K] or more at room temperature, and it may be formed of another metal that reflects light. Good. For example, the sealing container 22 may be formed by plating silver or aluminum as a reflective layer on copper. In addition, the sealing container 22 uses a material other than a metal such as a metal having a thermal conductivity of 50 [W / m · K] or more at room temperature or a ceramic, and reflects light by a process such as plating. You may form with the member processed in this way. In addition, although it is preferable that the heat conductivity of the material which forms the sealing container 22 of the light-emitting devices 1-3 is 50 [W / m * K] or more at normal temperature, depending on the amount of heat generated from the light-emitting diode 10, A material having a thermal conductivity of 50 [W / m · K] or less at room temperature may be used.

  Further, instead of the sealing container 22, a cylindrical member having no bottom plate portion may be used. When a cylindrical member is used instead of the sealing container 22, the cylindrical member and the mounting substrate 100 are joined by the same method as the joining between the sealing container 22 and the window plate member 20. The

  In addition, the fluorine-based inert liquid used as the cooling solution 30 of the light-emitting devices 1 to 3 may be any fluorine-based liquid as long as it is inert to the material such as the light-emitting diode, but from 3M (registered trademark) It is preferred to use the provided Fluorinert®. In addition, as the fluorine-based inert liquid, it is preferable to use Galden (registered trademark) provided by Solvay Solexis Sochieta Perathoni.

  Moreover, although the cooling solution 30 of the light-emitting devices 1 to 3 is a fluorine-based inert liquid, pure water may be used as the cooling solution 30. The cooling solution 30 is preferably a liquid having a boiling point of 150 ° C. or higher, and more preferably a liquid having a boiling point of 200 ° C. or higher.

  In addition, the wirings 45 and 46 of the power feeding unit 40 of the light emitting devices 1 to 3 are respectively disposed on the surface of the window plate member 20 opposite to the surface on which the light emitting diode 10 is mounted. The plate member 20 may be disposed on the surface on which the light emitting diode 10 is mounted.

  FIG. 10 is a diagram showing the light emitting device 4.

  The light emitting device 4 is different from the light emitting device 1 described with reference to FIGS. 2 to 5 in that the wirings 45 and 46 are arranged on the surface of the window plate member 20 on which the light emitting diode 10 is mounted.

  In the light emitting device 4, the wirings 45 and 46 are arranged on the surface of the window plate member 20 on which the light emitting diode 10 is mounted, and therefore no hole is formed in the window plate member 20. In the light emitting device 4, the step of forming a hole in the window plate member 20 can be omitted, and thus the number of manufacturing steps can be reduced as compared with the light emitting devices 1 to 3. Further, in the light emitting device 4, it is possible to reduce light loss due to light reflection and refraction occurring at the boundary between the ITO disposed inside the hole and the window plate member 20. Further, in the light emitting device 4, it is possible to prevent variation in the direction of light due to reflection and refraction of incident light that occurs at the boundary between the ITO disposed in the hole and the window plate member 20. Furthermore, since ITO has a relatively high refractive index, it is arranged in the order of the window plate member 20, ITO and air in the order of ITO, the window plate member 20 and air in the direction of the light path. The light can be extracted more easily.

  In the light emitting devices 1 to 4, the window plate member 20 is disposed to face the bottom surface 22 e of the sealing container 22 that contacts the mounting substrate surface 100, and the electrodes 41 and 42 are provided on the bottom surface 22 e of the sealing container 22. However, the electrodes 41 and 42 may be provided on any surface different from the surface on which the window plate member 20 of the sealing container 22 is disposed.

  FIG. 11 is a diagram illustrating the light emitting device 5.

  In the light emitting device 5, it is described with reference to FIGS. 2 to 5 that the bottom surface 22 e of the sealing container 22 does not contact the mounting substrate surface 100 but the side surface 22 c of the sealing container 22 contacts the mounting substrate surface 100. This is different from the light emitting device 1 described above. The light emission described with reference to FIGS. 2 to 5 is that the electrodes 41 and 42 are not provided on the bottom surface 22e of the sealing container 22 but the electrodes 41 and 42 are provided on the side surface 22c of the sealing container 22. Different from the device 1.

  In the light emitting device 5, the electrode 41 is connected to the light emitting diode 10 through a wiring 43, and the electrode 42 is connected to the light emitting diode 10 through wirings 44 a, 44 b and 46. However, like the electrode 41, the electrode 42 may be connected to the light emitting diode 10 only through the wiring formed on the window plate member 20 without using the wirings 44 a, 44 b and 46.

  Moreover, although the uneven | corrugated | grooved part 50 of the light-emitting device 2 is formed by integrally molding with the sealing container 22, it joins the member shape | molded separately from the sealing container 22 to the bottom face part 22e of the sealing container 22. The uneven portion 50 may be formed by the above. In this case, the concavo-convex portion 50 is formed of a material whose thermal conductivity is 50 [W / m · K] or higher at room temperature and whose inner surface is processed to reflect light by a process such as plating. May be.

  Moreover, although the uneven | corrugated | grooved part 50 of the light-emitting device 2 has the shape of a concave Fresnel lens shape, it is good also as other uneven | corrugated shapes, such as a random uneven | corrugated shape. The concavo-convex portion 50 can have a preferable shape according to the application in which the light emitting device 2 is used and the number of light emitting diodes mounted on the light emitting device 2.

  Moreover, although the uneven | corrugated | grooved part 50 of the light-emitting device 2 is formed on the inner surface of the bottom face part 22e of the sealing container 22, you may form on the inner surface of the side wall parts 22a-22d of the sealing container 22.

  Moreover, although the uneven | corrugated | grooved part 52 of the light-emitting device 3 is formed by integrally molding with the window board member 20, it joins the member shape | molded separately from the window board member 20 to the plate | board surface of the window board member 20. The uneven portion 52 may be formed. In this case, the uneven portion 52 may be formed of a member other than glass that transmits light.

  Moreover, although the uneven | corrugated | grooved part 52 of the light-emitting device 3 has the shape of a convex Fresnel lens shape, it is good also as other uneven | corrugated shapes, such as a random uneven | corrugated shape. The concavo-convex portion 52 can have a preferable shape according to the application in which the light emitting device 3 is used and the number of light emitting diodes mounted on the light emitting device 3.

  In the light emitting device 2, the uneven portion 50 is formed, and in the light emitting device 3, the uneven portion 52 is formed, but the light emitting device may have both the uneven portions 50 and 52. Further, the light emitting device may further include an uneven portion formed on the inner surfaces of the side wall portions 22a to 22d of the sealing container 22 in addition to the uneven portions 50 and 52.

1, 2, 3 Light-emitting device 10 Light-emitting diode 20 Window plate member 22 Sealing container 30 Cooling solution 40 Power supply portion 41, 42 Electrode 50, 52 Concavity and convexity portion 100 Mounting substrate

Claims (6)

A semiconductor light emitting device;
A window plate member capable of transmitting light emitted from the semiconductor light emitting element, wherein the semiconductor light emitting element is flip-chip mounted;
A cooling solution for cooling the semiconductor light emitting device;
A sealing container for sealing the cooling solution in the window plate member in cooperation with the inside;
In the sealing container, mounting electrodes provided on any surface different from the surface on which the window plate member is disposed,
A light emitting device comprising:   The light emitting device according to claim 1, wherein the sealing container material forming the sealing container includes aluminum, or copper plated with aluminum or silver.   The light emitting device according to claim 1, wherein an uneven portion is formed on an inner surface of the sealing container.   The light emitting device according to any one of claims 1 to 3, wherein an uneven portion is formed on a surface of the window plate member on which the semiconductor light emitting element is mounted.   The light emitting device according to claim 3, wherein the uneven portion convects the cooling solution.   The light emitting device according to any one of claims 3 to 5, wherein the uneven portion has a Fresnel lens shape.

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