JP2007042806A - Light emitting module, its manufacturing method, and projective light source unit for display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light emitting module with uniform irradiation pattern and a projective light source unit for display device using the module. <P>SOLUTION: The light emitting module comprises a substrate, an electrode formed on one principal surface of the substrate, and a plurality of light emitting elements mounted on the foregoing principal surface. The light emitting element includes a semiconductor multilayer film composed of a first conductive semiconductor layer, a light emitting layer, and a second conductive semiconductor layer stacked in this order from the side of the substrate. An outer peripheral end of an upper surface part of the second conductive semiconductor layer and the foregoing electrode are electrically connected, and the lower surface of the first conductive semiconductor layer and the foregoing electrode are electrically connected. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a light emitting module, a method for manufacturing the same, and a light source unit for a projection display device using the light emitting module.

  A light-emitting diode (LED) is known as a light-emitting element including a semiconductor multilayer film. This light emitting element is used as a light source for liquid crystal backlight, a light source for indicator, a light source for display, a light source for reading sensor, and the like. In particular, with the recent increase in the output of LEDs, LEDs are being put into practical use as light sources for projection display devices that display images on an irradiation surface such as a screen (see, for example, Patent Document 1).

  FIG. 13 shows a schematic plan view of a light source for a projection display device using a conventional LED. As shown in FIG. 13, the projection display light source 100 includes a red light emitting module 101R, a green light emitting module 101G, and a blue light emitting module 101B, and each light emitting module 101R, 101G, 101B has a light emitting surface on each light emitting surface side. An integrator lens 102 that equalizes the light intensity in a plane orthogonal to the optical axis of the incident light, a collimator lens 103 that shapes the emitted light from the integrator lens 102 into parallel light, and at least one of the light emitted from the collimator lens 103 A liquid crystal array switch 104 that switches between display and non-display according to each pixel of a projected screen (not shown) by transmitting or blocking the part is disposed. Further, a combining prism 105 is disposed on the front surface of the liquid crystal array switch 104. The combining prism 105 refracts the light emitted from the liquid crystal array switch 104, and projects the light onto the screen with the same emission direction. A heat sink 106 is mounted on the back side of each light emitting module 101R, 101G, 101B, and heat generated from each light emitting module 101R, 101G, 101B is dissipated from the heat sink 106.

  FIG. 14A is a sectional view of a conventional LED, and FIG. 14B is a plan view of the LED bare chip. As shown in FIG. 14A, the LED 200 includes a substrate 201, an electrode 202 formed on the substrate 201, and an LED bare chip 203 flip-chip mounted on the electrode 202. The LED bare chip 203 includes a sapphire substrate 210, an n-type semiconductor layer 211, a light emitting layer 212, and a p-type semiconductor layer 213 sequentially stacked on the sapphire substrate 210. The light emitting layer 212 is not in contact with a part 211a of the main surface of the n-type semiconductor layer 211 on the substrate 201 side, and an n-side electrode 214a is provided. The n-type semiconductor layer 211 is electrically connected to the electrode 202 through the n-side electrode 214a and the conductive adhesive layer 215. The p-type semiconductor layer 213 is electrically connected to the electrode 202 through the p-side electrode 214b and the conductive adhesive layer 215. From the above structure, as shown in FIG. 14B, the region above the n-side electrode 214a in the light emitting surface of the LED bare chip 203 becomes the non-light emitting portion 204a, and the other portion becomes the light emitting portion 204b.

FIG. 15A is a sectional view of another conventional LED, and FIG. 15B is a plan view of the LED bare chip. As shown in FIG. 15A, the LED 300 includes a substrate 301, an electrode 302 formed on the substrate 301, and an LED bare chip 303 mounted on the electrode 302. The LED bare chip 303 includes a SiC substrate 310, an n-type semiconductor layer 311, a light emitting layer 312, and a p-type semiconductor layer 313 sequentially stacked on the SiC substrate 310. SiC substrate 310 and electrode 302 are electrically connected by wire 305 through upper surface electrode 304. The p-type semiconductor layer 313 is electrically connected to the electrode 302 via the p-side electrode 314 and the conductive adhesive layer 315. From the above structure, as shown in FIG. 15B, the upper electrode 304 and the wire 305 provided on the light emitting surface of the LED bare chip 303 are blocked from light emission and become a shadow portion 306.
JP-A-10-123512

  When the light emitted from the light source for a projection display device having the LDE 200 or 300 having the above-described configuration is collimated by a collimator lens, a part of the irradiation pattern may be lost due to the influence of the non-light-emitting portion 204a or the shadow portion 306, There is a problem that the shadow part 306 is projected onto the irradiation pattern. Therefore, the conventional projection display light source 100 uses the integrator lens 102 to uniform the light intensity before collimating the emitted light to obtain a uniform irradiation pattern. However, when the integrator lens 102 is used, there is a problem that the size and weight of the light source for the projection display device increase.

  The present invention solves the above-described conventional problems, and provides a thin and lightweight light source for a projection display device, a light emitting module used therefor, and a manufacturing method thereof.

  The light emitting module of the present invention is a light emitting module including a substrate, an electrode formed on one principal surface of the substrate, and a plurality of light emitting elements mounted on the one principal surface, A first conductive type semiconductor layer, a light emitting layer, and a second conductive type semiconductor layer including a semiconductor multilayer film laminated in this order from the substrate side, and an outer peripheral edge of an upper surface portion of the second conductive type semiconductor layer The portion and the electrode are electrically connected, and the lower surface portion of the first conductivity type semiconductor layer and the electrode are electrically connected.

  In the first light emitting module manufacturing method of the present invention, a semiconductor layer is formed by laminating a second conductive semiconductor layer, a light emitting layer, a first conductive semiconductor layer, and an entire surface electrode in this order on a first substrate. Dividing the semiconductor layer into a plurality of layers, and laminating the second conductive semiconductor layer, the light emitting layer, the first conductive semiconductor layer, and the entire surface electrode in this order on the first substrate. A step of forming a plurality of the light emitting elements, a step of forming a plurality of electrodes on the second substrate, and joining the first substrate and the second substrate, A step of bonding the electrode of the second substrate, a step of removing the first substrate after the bonding, and a current collecting electrode is provided at an outer peripheral end of the upper surface portion of the second conductivity type semiconductor layer And electrically connecting the current collecting electrode and the electrode of the second substrate. And butterflies.

  In the second light emitting module manufacturing method of the present invention, the second conductive semiconductor layer, the light emitting layer, the first conductive semiconductor layer, and the entire surface electrode are laminated on the first substrate in this order. A step of dividing the first substrate on which the semiconductor layer is formed into a plurality of portions to form a light emitting element, and a step of forming a plurality of electrodes on the second substrate. Joining the plurality of first substrates and the second substrate to join the whole surface electrodes of the plurality of light emitting elements and the electrodes of the second substrate; and after the joining, the first substrate A step of removing the first substrate, a step of providing a current collecting electrode at an outer peripheral end of the upper surface portion of the second conductive semiconductor layer, and electrically connecting the current collecting electrode and the electrode of the second substrate It is characterized by including.

  The light source unit for a projection display device uses the light emitting module of the present invention as a light source.

  Since the light emitting module of the present invention does not block the emitted light on the light emitting surface, uniform light emission can be realized. Moreover, since the light source unit for projection type display apparatuses of this invention uses the light emitting module of this invention as a light source, it can make an irradiation pattern uniform, without using an integrator lens.

  The light emitting module manufacturing method of the present invention can reasonably manufacture the above light emitting module of the present invention.

  The light emitting module of the present invention includes a substrate, electrodes formed on one principal surface of the substrate, and a plurality of light emitting elements mounted on the one principal surface.

The base material constituting the substrate is not particularly limited. For example, a ceramic base material made of Al ₂ O ₃ , AlN or the like, a semiconductor base material made of Si or the like, or an electric insulating material layer is laminated on a metal layer. Laminated substrates can be used. As the electrical insulating material layer, for example, a composite material containing 70 to 95% by mass of an inorganic filler and 5 to 30% by mass of a thermosetting resin composition can be used. In addition, the thickness of the base material which comprises the said board | substrate should just be 0.1-1 mm, for example.

  The light emitting element includes a semiconductor multilayer film in which a first conductive semiconductor layer, a light emitting layer, and a second conductive semiconductor layer are stacked in this order from the substrate side.

  In the light emitting element having the above structure, the second conductivity type semiconductor layer side is the light emitting surface. Here, the “first conductivity type” is a p-type or n-type conductivity type, and the “second conductivity type” is a conductivity type opposite to the first conductivity type. For example, when the first conductive semiconductor layer is a p-type semiconductor layer, the second conductive semiconductor layer is an n-type semiconductor layer. As the first conductivity type semiconductor layer, for example, a p-GaN layer that is a p-type semiconductor layer, an n-GaN layer that is an n-type semiconductor layer, or the like can be used. As the second conductivity type semiconductor layer, for example, a p-GaN layer that is a p-type semiconductor layer, an n-GaN layer that is an n-type semiconductor layer, or the like can be used, as in the case of the first conductivity type semiconductor layer. . As the light emitting layer, for example, a GaInN light emitting layer can be used. The thicknesses of the p-type semiconductor layer, the light emitting layer, and the n-type semiconductor layer may be, for example, 0.1 to 0.5 μm, 0.01 to 0.1 μm, and 0.5 to 3 μm, respectively.

  As the light emitting element, for example, a red LED that emits red light with a wavelength of 590 to 650 nm, a green LED that emits green light with a wavelength of 500 to 550 nm, a blue LED that emits blue light with a wavelength of 450 to 500 nm, and the like can be used. As the red LED, for example, an LED using an AlGaInP-based material can be used, as the green LED, for example, an LED using a GaInN-based material can be used, and as the blue LED, for example, an LED using a GaInN-based material Can be used.

  In addition, the outer peripheral end of the upper surface portion of the second conductivity type semiconductor layer and the electrode of the substrate are electrically connected, and the lower surface portion of the first conductivity type semiconductor layer and the electrode are electrically connected. Has been. By electrically connecting the outer peripheral end portion of the upper surface portion of the second conductivity type semiconductor layer on the light emitting surface side and the electrode, light can be emitted from the light emitting surface without being blocked.

  In order to improve current collection from the second conductivity type semiconductor layer, a current collecting electrode can be provided on the outer peripheral end of the upper surface portion of the second conductivity type semiconductor layer. As the current collecting electrode, for example, a Ti / Pt / Al electrode can be used. The thickness of the current collecting electrode is, for example, 0.1 to 1 μm.

  Furthermore, a transparent electrode can be formed on the second conductive semiconductor layer in order to improve current collection from the second conductive semiconductor layer. The transparent electrode can be formed of, for example, a conductive transparent oxide such as indium-tin composite oxide (ITO).

  Further, an entire surface electrode can be provided on the lower surface portion of the first conductivity type semiconductor layer in order to improve electrical connection between the first conductivity type semiconductor layer and the electrode of the substrate. For example, an Rh / Pt / Au electrode can be used as the full surface electrode. The thickness of the entire surface electrode is, for example, 0.5 to 2 μm.

  The plurality of light emitting elements are electrically connected to each other to form a light emitting module. Thereby, the light emission intensity can be increased.

  Next, the manufacturing method of the light emitting module of this invention is demonstrated. The manufacturing method of the light emitting module of this invention is a suitable manufacturing method of the light emitting module of this invention mentioned above. In addition, in the following description, the description which overlaps with description of the light emitting module of this invention mentioned above is abbreviate | omitted.

  In the first method for manufacturing a light emitting module of the present invention, a semiconductor layer is formed by laminating a second conductive semiconductor layer, a light emitting layer, a first conductive semiconductor layer, and an entire surface electrode in this order on a first substrate. And dividing the semiconductor layer into a plurality of layers, and laminating the second conductive semiconductor layer, the light emitting layer, the first conductive semiconductor layer, and the entire surface electrode in this order on the first substrate. A step of forming a plurality of the light emitting elements, a step of forming a plurality of electrodes on the second substrate, and joining the first substrate and the second substrate, A step of bonding the electrode of the second substrate, a step of removing the first substrate after the bonding, and providing a collecting electrode at the outer peripheral end of the upper surface portion of the second conductivity type semiconductor layer And a step of electrically connecting the current collecting electrode and the electrode of the second substrate.

  Thereby, the light emitting module which can be made to radiate | emit without interrupting | blocking light from a light emission surface can be manufactured rationally.

  Moreover, the 1st manufacturing method of the light emitting module of this invention can further include the process of laminating | stacking a transparent electrode on the said 2nd conductivity type semiconductor layer.

  In the second method for manufacturing a light emitting module of the present invention, a second conductive semiconductor layer, a light emitting layer, a first conductive semiconductor layer, and an entire surface electrode are stacked in this order on a first substrate. A step of dividing the first substrate on which the semiconductor layer is formed into a plurality of portions to form a light emitting element, and a step of forming a plurality of electrodes on the second substrate. Bonding the plurality of first substrates and the second substrate to bond the whole surface electrodes of the plurality of light-emitting elements and the electrodes of the second substrate; and after the bonding, the first substrate A step of removing the first substrate, and a step of providing a collecting electrode on the outer peripheral end of the upper surface portion of the second conductive semiconductor layer, and electrically connecting the collecting electrode and the electrode of the second substrate. Including.

  Thereby, the light emitting module which can be made to radiate | emit without interrupting | blocking light from a light emission surface can be manufactured rationally.

  Moreover, the 2nd manufacturing method of the light emitting module of this invention can further include the process of laminating | stacking a transparent electrode on the said 2nd conductivity type semiconductor layer.

  Next, the light source unit for a projection display device of the present invention will be described. The light source unit for a projection display device of the present invention uses the above-described light emitting module of the present invention as a light source. In addition, in the following description, the description which overlaps with description of the light emitting module of this invention mentioned above is abbreviate | omitted.

  Since the light source unit for a projection display device of the present invention uses the light emitting module of the present invention as a light source, the irradiation pattern can be made uniform without using an integrator lens.

  Further, the light source unit for a projection display device according to the present invention switches between display / non-display according to each pixel of the projected screen by transmitting or blocking at least part of the light emitted from the light emitting module. It may further include a liquid crystal panel for performing the above. As the liquid crystal panel, for example, a liquid crystal array switch in which a liquid crystal element section is divided corresponding to each pixel of a projected screen can be used.

  In addition, the light source unit for a projection display device of the present invention may further include a heat radiator that contacts a main surface opposite to the one main surface of the substrate of the light emitting module. This is because the heat generated from the light emitting element can be radiated from the heat radiating body, so that deterioration of the light emitting module due to heat can be prevented. The said heat radiator is not specifically limited, For example, a heat sink etc. can be used.

  The light source unit for a projection display device according to the present invention may further include a socket to which the light emitting module can be attached and detached. This is because the light emitting module can be easily replaced.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, in the following description, the description which overlaps with the above-mentioned description may be abbreviate | omitted.

(Embodiment 1)
First, an embodiment of the first light emitting module of the present invention will be described. FIG. 1 is a plan view showing a first light emitting module of the present invention, FIG. 2A is a cross-sectional view taken along the line II of FIG. 1, and FIG. 2B is a cross-sectional view of the main part of FIG. 2A and 2B, the light emitting module 1 includes a submount substrate 10 made of alumina, an electrode 11 made of Ti / Pt / Au formed on one main surface 10a of the submount substrate 10, and an upper surface of the one main surface 10a. And a plurality of light emitting elements 12 mounted on. The light emitting element 12 includes a p-GaInN layer (first conductivity type semiconductor layer) 12a, a GaInN light emission layer 12b, and an n-GaInN layer (second conductivity type semiconductor layer) 12c in this order from the submount substrate 10 side. Are stacked. A collector electrode 13 made of Ti / Pt / Al is provided on the outer peripheral end of the upper surface portion of the n-GaInN layer 12c, and the collector electrode 13 and the electrode 11 are made of a conductor 14 made of Ti / Pt / Al. Is electrically connected through. The collecting electrode 13 and the conductor 14 are integrally formed. The lower surface portion of the p-GaInN layer 12a and the electrode 11 are electrically connected via a full-surface electrode 15 made of Rh / Pt / Au and a conductive adhesive layer 16 made of Au / Sn. Each light emitting element 12 is electrically connected to each other through the electrode 11 and the conductor 14. An insulating layer 23 made of a silicon nitride film is disposed between the light emitting element 12 and the conductor 14.

  The electrode 11 is electrically connected to the back electrode 18 through a contact pin 17 made of Pt that penetrates the submount substrate 10. The submount substrate 10 is mounted on the module substrate 19. The module substrate 19 is formed of a laminate of an Al substrate 19a and a composite layer 19b, and a conductor pattern 20 is formed on the composite layer 19b. The back electrode 18 made of Ti / Au and the conductor pattern 20 are electrically connected via a conductive adhesive layer 21 made of solder or the like. Furthermore, the light emitting element 12 and the submount substrate 10 are covered with a transparent resin 22 made of an epoxy resin or a silicone resin. By providing sawtooth irregularities on the surface of the light emission surface (upper surface) of the transparent resin 22, reflection can be prevented and light extraction efficiency can be increased. The conductor pattern 20 is led out from the transparent resin 22 to form a power supply terminal 24 (FIG. 1).

  The light emitting module of the present embodiment can emit light without blocking from the light emitting surface of the light emitting element 12 by adopting the above configuration.

  Next, an example of the manufacturing method of the light emitting module of this embodiment is demonstrated. 3 to 6 to be referred to are process cross-sectional views illustrating the method for manufacturing the light emitting module of the present embodiment. 3 to 6, the same components as those in FIGS. 1 and 2 are denoted by the same reference numerals, and description thereof is omitted.

  First, as shown in FIG. 3A, an n-GaInN layer (second conductivity type semiconductor layer) 12c, a GaInN light emitting layer 12b, and a GaInN light emitting layer 12b are formed on a Si substrate (first substrate) 30 by crystal growth by MOCVD. A p-GaInN layer (first conductivity type semiconductor layer) 12a is formed. Next, as shown in FIG. 3B, a full-surface electrode 15 is formed on the p-GaInN layer 12a by sputtering. Next, as shown in FIG. 3C, part of the crystal-grown layer is partially removed by selective etching until it reaches the Si substrate 30, and the portion that becomes the light emitting element 12 is divided into a plurality of parts on the Si substrate 30. To form.

  Subsequently, as shown in FIG. 4D, a submount substrate (second substrate) 10 including contact pins 17 is prepared. Next, as shown in FIG. 4E, a plurality of electrodes 11 and a conductive adhesive layer 16 are formed on the main surface of the submount substrate 10. Further, a back electrode 18 is formed on the surface opposite to the one main surface of the submount substrate 10 by plating. Next, as shown in FIG. 4F, the entire surface electrode 15 of the light emitting element 12 formed on the Si substrate 30 and the conductive adhesive layer 16 formed on the submount substrate 10 are overlapped, and the temperature is raised to about 300 ° C. while pressing. As a result, the entire surface electrode 15 and the conductive adhesive layer 16 are joined.

  Next, as shown in FIG. 5G, the Si substrate 30 (FIG. 4F) is scraped off to about 30 μm by mechanical polishing, and the remaining Si substrate 30 is removed by chemical etching with NaOH or the like. At this time, the surface 31 of the n-GaInN layer 12c is also slightly etched to form innumerable pits on the surface 31. Next, as shown in FIG. 5H, after the insulating layer 23 is formed around the light emitting element 12, the current collecting electrode 13 and the conductor 14 are integrally formed at the outer peripheral end of the surface 31 of the n-GaInN layer 12c. Then, the current collecting electrode 13 and the electrode 11 are electrically connected. Next, as shown in FIG. 5I, the submount substrate 10 is divided into individual pieces to obtain a submount substrate 32 with a light emitting element.

  Subsequently, as shown in FIG. 6A, the conductor pattern 20 and the power supply terminal 24 are formed on the module substrate 19. Next, as shown in FIG. 6B, a conductive adhesive layer 21 is formed on the conductor pattern 20. Next, as shown in FIG. 6C, the submount substrate 32 with a light emitting element is disposed on the module substrate 19, and the back electrode (18) and the conductive adhesive layer (21) are ultrasonically bonded. Finally, as shown in FIG. 6D, the light emitting module of this embodiment is obtained by covering the submount substrate 32 with the light emitting element with the transparent resin 22.

  Although omitted in the present embodiment, an ITO electrode (transparent electrode) may be further formed on the n-GaInN layer 12c by sputtering or the like.

(Embodiment 2)
Next, an embodiment of the second light emitting module of the present invention will be described. FIG. 7 is a plan view showing a second light emitting module of the present invention, and FIG. 8 is a sectional view taken along line II-II in FIG. The light emitting module of the present embodiment has substantially the same structure as the light emitting module of the first embodiment except that the submount substrate is removed from the light emitting module of the first embodiment, and the same components as those in FIGS. Are given the same reference numerals.

  In FIG. 8, the light emitting module 1 is mounted on a module substrate 40 made of alumina, a conductor pattern 20 made of Ti / Pt / Au formed on one main surface 40a of the module substrate 40, and one main surface 40a. A plurality of light emitting elements 12. The light emitting element 12 includes a p-AlGaInP layer (first conductivity type semiconductor layer) 12d, an AlGaInP light emission layer 12e, and an n-AlGaInP layer (second conductivity type semiconductor layer) 12f stacked in this order from the module substrate 40 side. Has been. A collector electrode 13 made of Ti / Pt / Al is provided at the outer peripheral end of the upper surface portion of the n-AlGaInP layer 12f, and the collector electrode 13 and the conductor pattern 20 are made of a conductor made of Ti / Pt / Al. 14 is electrically connected. The collecting electrode 13 and the conductor 14 are integrally formed. The lower surface portion of the p-AlGaInP layer 12d and the conductor pattern 20 are electrically connected through a full-surface electrode 15 made of Rh / Pt / Au and a conductive adhesive layer 16 made of Au / Sn. Each light emitting element 12 is electrically connected to each other through the conductor pattern 20 and the conductor 14.

  The light emitting element 12 is covered with a transparent resin 22 made of an epoxy resin. Note that an insulating layer 23 made of a silicon nitride film is disposed between the light emitting element 12 and the conductor 14. The conductor pattern 20 is led out from the transparent resin 22 to form a power supply terminal 24 (FIG. 1).

  The light emitting module of the present embodiment can emit light without blocking from the light emitting surface of the light emitting element 12 by adopting the above configuration.

  Next, an example of the manufacturing method of the light emitting module of this embodiment is demonstrated. 9 to 11 to be referred to are process cross-sectional views illustrating the method for manufacturing the light emitting module of the present embodiment. 9 to 11, the same components as those in FIGS. 3 to 5 are denoted by the same reference numerals.

  First, as shown in FIG. 9A, an n-AlGaInP layer (second conductivity type semiconductor layer) 12f and an AlGaInP light emitting layer 12e are formed on an n-GaAs substrate (first substrate) 41 by crystal growth by MOCVD. Then, a p-AlGaInP layer (first conductivity type semiconductor layer) 12d is formed. Next, as shown in FIG. 3B, a full-surface electrode 15 is formed on the p-AlGaInP layer 12d by sputtering. Next, as shown in FIG. 3C, the n-GaAs substrate 41 is divided into pieces by a grinder 42.

  Subsequently, as shown in FIG. 10D, a plurality of conductor patterns 20 and a conductive adhesive layer 16 are formed on one main surface of the module substrate 40 (second substrate). Next, as shown in FIG. 10E, the entire surface electrode 15 of the light emitting element 12 formed on the n-GaAs substrate 41 and the conductive adhesive layer 16 formed on the module substrate 40 are overlapped and heated to about 300 ° C. while pressing. By raising, the whole surface electrode 15 and the conductive adhesive layer 16 are joined. Next, as shown in FIG. 5F, the n-GaAs substrate 41 (FIG. 5E) is removed by polishing and chemical etching with NaOH or the like. At this time, the surface 31 of the n-AlGaInP layer 12 f is also slightly etched, and innumerable pits are formed on the surface 31.

  Next, as illustrated in FIG. 11G, an insulating layer 23 is formed around the light emitting element 12. Next, as shown in FIG. 11H, the collector electrode 13 and the conductor 14 are integrally formed at the outer peripheral end of the surface 31 of the n-AlGaInP layer 12f, and the collector electrode 13 and the conductor pattern 20 are electrically connected. Connect to. Finally, as shown in FIG. 11I, the light emitting module of this embodiment is obtained by covering the light emitting element 12 with a transparent resin 22.

  Although omitted in the present embodiment, an ITO electrode (transparent electrode) may be further formed on the n-AlGaInP layer 12f by sputtering or the like.

(Embodiment 3)
Next, an embodiment of a light source unit for a projection display device of the present invention will be described. FIG. 12 is a schematic plan view showing an example of a light source unit for a projection display device of the present invention. The light source unit for a projection display device according to the present embodiment uses a light emitting module having the same structure as the light emitting module described in the first or second embodiment.

  As shown in FIG. 12, the light source unit 50 for a projection display device includes a red light emitting module 51R, a green light emitting module 51G, and a blue light emitting module 51B, and on the light emitting surface side of the light emitting modules 51R, 51G, 51B, A liquid crystal array switch 52 that switches between display and non-display according to each pixel of the projected screen 56 by transmitting or blocking at least part of the light emitted from 51R, 51G, and 51B, and the emitted light A collimator lens 53 for shaping into parallel light is disposed. Further, a multiplexing prism 54 is disposed on the front surface of the collimator lens 53. By refracting the outgoing light by the combining prism 54, the directions of the outgoing lights from the light emitting modules 51R, 51G, 51B are matched. A projection lens 55 is disposed in front of the multiplexing prism 54, and the emitted light is projected onto the screen 56 by the projection lens 55. A heat sink 57 is mounted on the back side of each light emitting module 51R, 51G, 51B, and heat generated from each light emitting module 51R, 51G, 51B is radiated from the heat sink 57.

  Since the light source unit 50 for the projection display device of the present embodiment uses the light emitting module of the first embodiment or the second embodiment, the irradiation pattern can be made uniform without using an integrator lens. Further, since no integrator lens is used, a thin and lightweight light source unit for a projection display device can be provided.

  The light emitting module of the present invention and the light source unit for a projection display device using the light emitting module are useful for realizing a thin and lightweight projection display device and the like because the irradiation pattern can be made uniform without using an integrator lens. .

It is a top view which shows the 1st light emitting module of this invention. 1A is a cross-sectional view taken along the line II of FIG. 1, and B is a cross-sectional view of the main part of A. FIG. It is process sectional drawing explaining the manufacturing method of the light emitting module of Embodiment 1. FIG. It is process sectional drawing explaining the manufacturing method of the light emitting module of Embodiment 1. FIG. It is process sectional drawing explaining the manufacturing method of the light emitting module of Embodiment 1. FIG. It is process sectional drawing explaining the manufacturing method of the light emitting module of Embodiment 1. FIG. It is a top view which shows the 2nd light emitting module of this invention. It is sectional drawing of the II-II line | wire of FIG. It is process sectional drawing explaining the manufacturing method of the light emitting module of Embodiment 2. FIG. It is process sectional drawing explaining the manufacturing method of the light emitting module of Embodiment 2. FIG. It is process sectional drawing explaining the manufacturing method of the light emitting module of Embodiment 2. FIG. It is a schematic plan view which shows an example of the light source unit for projection type display apparatuses of this invention. It is a schematic plan view of the light source for projection type display apparatuses using conventional LED. A is a sectional view of a conventional LED, and B is a plan view of the LED bare chip. A is a sectional view of another conventional LED, and B is a plan view of the LED bare chip.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light emitting module 10 Submount board | substrate 11 Electrode 12 Light emitting element 12a p-GaInN layer 12b GaInN light emitting layer 12c n-GaInN layer 12d p-AlGaInP layer 12e AlGaInP light emitting layer 12f n-AlGaInP layer 13 Current collecting electrode 14 Conductor 15 Whole surface electrode 16 Conductive adhesive layer 17 Contact pin 18 Back electrode 19 Module substrate 19a Al substrate 19b Composite layer 20 Conductive pattern 21 Conductive adhesive layer 22 Transparent resin 23 Insulating layer 24 Feed terminal 30 Si substrate 31 Surface 32 Submount substrate with light emitting element 40 Module substrate 41 n-GaAs substrate 42 grinder 50 light source unit 51R for projection display device red light emitting module 51G green light emitting module 51B blue light emitting module 52 liquid crystal array switch 53 collimator lens 5 Multiplexing prism 55 projection lens 56 screen 57 heatsink

Claims (13)

A light-emitting module including a substrate, electrodes formed on one principal surface of the substrate, and a plurality of light-emitting elements mounted on the one principal surface;
The light emitting element includes a semiconductor multilayer film in which a first conductive semiconductor layer, a light emitting layer, and a second conductive semiconductor layer are stacked in this order from the substrate side,
The outer peripheral end of the upper surface portion of the second conductivity type semiconductor layer and the electrode are electrically connected,
The light emitting module, wherein the lower surface portion of the first conductivity type semiconductor layer and the electrode are electrically connected.   The light emitting module according to claim 1, wherein a current collecting electrode is further formed on an outer peripheral end of the upper surface portion of the second conductivity type semiconductor layer.   The light emitting module according to claim 1, wherein a full-surface electrode is further formed on a lower surface portion of the first conductivity type semiconductor layer.   The light emitting module according to claim 1, wherein a transparent electrode is further formed on the second conductive semiconductor layer.   The light emitting module according to claim 1, wherein the plurality of light emitting elements are electrically connected to each other. A step of forming a semiconductor layer by laminating a second conductive semiconductor layer, a light emitting layer, a first conductive semiconductor layer, and an entire surface electrode in this order on a first substrate;
A light emitting device in which the semiconductor layer is divided into a plurality of layers, and the second conductive semiconductor layer, the light emitting layer, the first conductive semiconductor layer, and the entire surface electrode are stacked in this order on the first substrate. A step of forming a plurality,
Forming a plurality of electrodes on a second substrate;
Bonding the first substrate and the second substrate to bond the entire surface electrode of the light emitting element and the electrode of the second substrate;
Removing the first substrate after the bonding;
Providing a current collecting electrode on an outer peripheral end of the upper surface portion of the second conductivity type semiconductor layer, and electrically connecting the current collecting electrode and the electrode of the second substrate;
The manufacturing method of the light emitting module characterized by including.   The manufacturing method of the light emitting module of Claim 6 which further includes the process of laminating | stacking a transparent electrode on the said 2nd conductivity type semiconductor layer. A step of forming a semiconductor layer by laminating a second conductive semiconductor layer, a light emitting layer, a first conductive semiconductor layer, and an entire surface electrode in this order on a first substrate;
Dividing the first substrate on which the semiconductor layer is formed into a plurality of parts to form a light emitting element;
Forming a plurality of electrodes on a second substrate;
Bonding the plurality of divided first substrates and the second substrate to bond the whole surface electrodes of the light emitting elements and the electrodes of the second substrate;
Removing the first substrate after the bonding;
Providing a current collecting electrode on an outer peripheral end of the upper surface portion of the second conductivity type semiconductor layer, and electrically connecting the current collecting electrode and the electrode of the second substrate;
The manufacturing method of the light emitting module characterized by including.   The method for manufacturing a light emitting module according to claim 8, further comprising a step of laminating a transparent electrode on the second conductive type semiconductor layer.   A light source unit for a projection display device, wherein the light emitting module according to claim 1 is used as a light source.   The projection according to claim 10, further comprising a liquid crystal panel that switches between display and non-display according to each pixel of the projected screen by transmitting or blocking at least part of the light emitted from the light emitting module. Light source unit for type display device.   The light source unit for a projection display device according to claim 10, wherein the light emitting module further includes a radiator.   The light source unit for a projection display device according to claim 10, further comprising a socket to which the light emitting module can be attached and detached.

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