JP4026659B2 - Side-emitting type light emitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor device having high mounting precision with respect to other components. <P>SOLUTION: The semiconductor device comprises a semiconductor element 4 and a support member 1 having a recess for housing the semiconductor device 4 and lead electrodes 2 connected to the semiconductor device 4. A main surface of the support member 1 is characterized by comprising at least a first main surface 1a and a second main surface 1b from the recess side. Further, there is a level difference between the first main surface 1a and the second main surface 1b. Further, the second main surface 1b has a recessed shape and a projecting shape and forms an outer wall having an inside cavity. <P>COPYRIGHT: (C)2006,JPO&amp;NCIPI

Description

  The present invention relates to a light emitting device used for a backlight of a liquid crystal display, a panel meter, an indicator lamp, a surface emitting switch, and the like, a light receiving device used for an optical sensor, and an optical device using them.

  Today, there is provided a semiconductor device having a semiconductor element typified by a light-emitting element and a light-receiving element, and a support provided with a lead electrode that protects the light-emitting element and the light-receiving element from the external environment and connects to those electrodes. Yes.

  In particular, as a light emitting device, a light emitting diode capable of emitting white mixed light with high luminance by combining a light emitting element and a phosphor that emits light having different wavelengths by absorbing light from the light emitting element has been developed. . As a result, light sources configured by arranging a plurality of these light emitting diodes are used in various fields. In such a light emitting diode, a light emitting element is fixed to a support body called a package to form a light emitting device. For example, a light-emitting surface of a light-emitting device is provided in a direction substantially perpendicular to the mounting surface of the light-emitting device, and can be irradiated with light in a direction substantially parallel to the mounting surface of the light-emitting device (see, for example, Patent Document 1) .).

  In addition, after the light of the light emitting diode is incident from the light incident surface of the light transmissive member to which the light emitting device such as the light emitting diode is fixed and guided in the light transmissive member, the light emission surface of the light transmissive member Light sources that extract light from the side are known. Examples of such a light source include a planar light source such as a backlight for a liquid crystal display.

JP 2000-196153.

  However, the package disclosed in Patent Document 1 includes a thin film electrode provided on an insulating substrate, and the outer shape of the package is determined only by the insulating substrate. Here, the insulating substrate is highly contracted at high temperatures, and it is difficult to obtain a certain shape. Further, if an insulating substrate is used, there is a limit to downsizing of the package. Furthermore, since the thin film electrode is used, the heat dissipation becomes poor as the size is reduced.

  Therefore, by using a molded body formed by resin injection molding as a package, the light emitting device is reduced in thickness and size, and heat dissipation is improved. Such a package is integrally molded so that the lead electrode is inserted into the package, and after forming the package, the lead electrode has a shape that is easy to mount on the mounting board by bending the portion protruding from the side surface of the package. The Here, since the lead electrode on which the semiconductor element is placed can be easily made relatively large with respect to the overall size of the package, the heat dissipation of the semiconductor device can be improved. However, a package formed by resin injection molding has a tolerance due to the strength of bending the lead electrode (forming), and it is difficult to obtain a certain shape with high productivity. Therefore, when a plurality of semiconductor devices are accurately fitted into an external support or an optical member, it is necessary to provide external shapes corresponding to the external shapes of different packages on the external support or the optical member, respectively. It was difficult to assemble.

  Therefore, the present invention solves the above problems and provides a semiconductor device excellent in mass productivity and mountability and an optical device using the same.

The present invention includes a light emitting element, a support having a recess for placing the light-emitting element, provided with a lead electrode connected to the light emitting element, among the side surfaces of the upper Symbol support, mainly with the recess A side-emitting light-emitting device having a mounting surface that is one of the side surfaces provided perpendicular to the surface and in the longitudinal direction of the recess, wherein the lead electrode has a connection terminal portion protruding from the side surface of the support. And the side surface of the short side of the said recessed part has the recessed part which arrange | positions a hanger lead, and an inclined surface among the side surfaces of the support body arrange | positioned by bending the connecting terminal part.

According to the present invention, a thin side-emitting light-emitting device with high mountability in which the connection terminal portion of the lead electrode is disposed at a predetermined position can be obtained.

  By forming a light emitting device having a semiconductor light emitting element having a longitudinal direction and a short direction and a package according to the present invention, even if the light emitting device is thinned, the semiconductor light emitting element is placed over the entire bottom surface of the recess. Further, the light extraction efficiency of the light emitting device can be improved, and the deterioration of the support using the organic material can be prevented.

  As a result of various experiments, the present inventor has improved the mountability by providing an external shape capable of positioning with other members in a portion where the shape is difficult to change due to a thermal action in a semiconductor device using an insert type package. As a result, the present invention has been found. That is, in the semiconductor device according to the present invention, the main surface of the support has at least a first main surface and a second main surface from the recess for housing the semiconductor element. Due to the presence of the at least two main surfaces, it is possible to easily perform high-precision positioning with an optical member such as a light guide plate.

  Hereinafter, embodiments according to the present invention will be described with reference to the drawings, particularly using a light emitting device as an example. It goes without saying that the semiconductor device according to the present invention is not limited to a light emitting device. 1 to 5 are a schematic perspective view (a) of a light emitting device according to the present invention and a schematic cross-sectional view (b) when the light emitting device is cut in a direction perpendicular to the light emitting surface. Show. FIGS. 16A to 16D are schematic cross-sectional views showing a package molding process in the present embodiment.

  In the light emitting device of the present embodiment, for example, as shown in FIG. 1, the package 1 is integrally molded so that one end portions of both positive and negative lead electrodes 2 are inserted into the package 1. More specifically, the package 1 has a recess capable of accommodating the light emitting element 4 on the main surface side, and one end portion of the positive lead electrode and one end portion of the negative lead electrode are formed on the bottom surface of the recess. Are separated from each other so that their main surfaces are exposed, and an insulating molding material is filled between the positive lead electrode and the negative lead electrode. Here, in this specification, the “main surface” refers to a surface on the light emitting surface side from which light of the semiconductor light emitting element is extracted with respect to the surface of each component of the semiconductor device such as a package and a lead electrode. Further, in the present invention, the shape of the light emitting surface formed on the main surface of the light emitting device is not limited to the quadrangular shape as shown in FIG. 1, but may be an elliptical shape as shown in FIG. By adopting such a shape, the light emitting surface can be made as large as possible while maintaining the mechanical strength of the side wall portion of the package that forms the recess, and a light emitting device that can irradiate a wide range even if it is thinned. it can.

  In the light emitting device of the present embodiment, the positive lead electrode and the negative lead electrode 2 are inserted so that the other end portions protrude from the package side surface. The protruding portion of the lead electrode is bent toward the back surface facing the main surface of the package or toward the mounting surface that is perpendicular to the main surface. Here, in the light-emitting device of the present embodiment, a surface that is perpendicular to the main surface and parallel to the longitudinal direction of the recess is a mounting surface, and a side surface that emits light in a direction substantially parallel to the mounting surface. This is a light emitting type light emitting device.

  The package 1 used in the light emitting device of the present embodiment has a recess formed on the main surface side by the package inner wall surface 8 and has a step on the side wall portion of the package main surface adjacent to the recess. Specifically, it has at least a first main surface 1a adjacent to the recess and a second main surface 1b that is one step lower than the first main surface 1a. That is, there is a step between the first main surface 1a and the second main surface 1b. This step need not be perpendicular to the first and second major surfaces. In order to easily fit the semiconductor device according to the present invention into an external support or an optical member such as a light guide plate, the semiconductor device may be inclined. In addition, it is not limited to the shape which has the 1st main surface 1a and the 2nd main surface 1b, Furthermore, you may provide a 3rd main surface, a 4th main surface, ... and 3 or more main surfaces. Absent. By being configured in this manner, the first main surface 1a, the second main surface 1b, and the side wall of the step structure that can be provided between the first main surface 1a and the second main surface 1b, The outer shape that can be positioned with the optical member is formed in a fixed shape. That is, in order to improve the luminance of the light-emitting device of the present invention or to provide desired optical characteristics, an optical member such as a lens having a specific shape is provided, or a planar light source combining the light-emitting device of the present invention and a light guide plate It may be. At that time, the main surface side shape having at least the first main surface 1a and the second main surface 1b of the light emitting device and the shape that can be fitted without a gap are provided in the optical member or the like, thereby assembling easily and accurately. Therefore, a light source excellent in mass productivity and optical characteristics can be obtained. In the present embodiment, the main surface has a step between the first main surface 1a and the second main surface 1b. However, the present invention is not limited to the shape having the step, and FIG. As shown, it is good also as a main surface which continues so that the 2nd main surface 1b may incline with respect to the 1st main surface 1a. By processing the mounting surface of the optical member into a shape that can be fitted into the continuous first main surface 1a and the second main surface 1b without a gap, the present invention can be used without any particular step. It is a light-emitting device excellent in mounting property with the optical member.

  Figures 17 to 26 show various embodiments of the present invention. According to the embodiment shown in FIG. 17, the second main surface 1b is formed by convex shapes at both ends of the support (package 1). This convex shape is preferably formed on the outer side of the inner wall surface assuming a surface obtained by extending the inner wall surface 8 of the package forming the recess in the direction of the light emission observation surface. With this configuration, a light emitting device in which the convex shape does not hinder light output can be obtained. In addition, the convex shape does not need to be provided at both ends of the package 1, and may be provided singularly or plurally at a location convenient for positioning the optical member such as a light guide plate or the mounting substrate and the semiconductor device. Note that this convex shape does not need to be perpendicular to the longitudinal direction of the package 1 and may be inclined like a groove-shaped concave portion shown in FIG. Furthermore, the connecting line between the convex shape and the first main surface 1a does not have to be a straight line but may be a curved line.

  19 and 20 show an example in which the second main surface 1b is formed by a disk-shaped concave portion or convex portion. That is, the second main surface 1b shown in FIGS. 19 and 20 is a bottom surface of a disk-shaped concave portion and an uppermost surface of the disk-shaped convex portion, respectively. The disk-shaped concave portion or convex portion need not be circular, but may be polygonal.

  Furthermore, the concave portion or the convex portion may have a groove shape as shown in FIG. Furthermore, as shown in FIGS. 22 and 23, the concave portion or the convex portion may be an annular groove or an annular wall having a hollow inside. Needless to say, the shape of the concave portion or the convex portion in the present embodiment is not limited to an annular shape, and may be a polygonal shape.

  24 to 26 show an embodiment in which a concave portion or a convex portion is further formed on the second main surface. Here, the support in FIGS. 24 to 26 has a third main surface in addition to the first and second main surfaces. That is, the third main surface shown in FIGS. 24 and 26 is a convex top surface, and the third main surface shown in FIG. 25 is a concave bottom surface. By comprising in this way, the semiconductor device concerning this invention can position with the optical member which has the shape which can be fitted with the shape of a main surface, and highly accurate. The convex shape in this embodiment is preferably formed integrally with the support, but is formed by fixing a member made of the same material as or a different material to the main surface of the support. Also good.

  As is clear from the above embodiments, the shape constituted by the first main surface and the second main surface in the package of the present invention is the positioning of the semiconductor device of the present invention, the flow of the adhesive, or other It can be freely determined in consideration of factors such as the size and shape of the semiconductor element.

  FIGS. 16A to 16D are schematic cross-sectional views showing the molding process of the package 1 in the present embodiment. Hereinafter, the molding method of the package according to the present invention will be described in order as (a) to (d). First, (a) a lead frame 24 formed by punching a metal flat plate is sandwiched between a pair of forming molds 27 and 28 and formed by inner walls of the protruding mold 27 and the recessed mold 28. A lead frame 24 is placed in the cavity to be formed. At this time, it arrange | positions so that the front-end | tip part of the lead frame 24 formed as a pair of positive / negative lead electrode in a post process may mutually oppose at predetermined intervals. The convex mold 27 has at least one rod-like protruding member 25 (for example, a pin) fitted in the through hole, and is movable in the direction of the cavity and the concave mold 28. Next, (b) the package molding material 26 is injected into the gate provided in the cavity direction with respect to the concave mold 28, and the inside of the cavity is filled with the package molding material 26. The injection direction of the package molding material is shown as an arrow in the package molding material injection direction 29 in FIG. Further, when the package molding material 26 is injected, as shown in FIG. 16B, the lower surface of the protruding member 25 is substantially flush with the inner wall surface of the convex mold 27 (the surface forming the second main surface). However, when the unevenness is formed on the second main surface, the lower surface of the protruding member 25 is disposed so as to protrude to the concave mold 28 to some extent. (C) The molding material filled in the cavity is cured by heating and cooling. (D) First, the concave mold 28 is removed, the second main surface 1b of the package main surface is used as a pin knock surface, the lower surface of the protruding member 25 is pressed against the second main surface 1b, and the protruding member 25 is directed to the concave mold 28. The package 1 is removed from the convex mold 27 by moving to. In addition, the moving direction of the protrusion member 25 is shown as an arrow of the protrusion direction 30 in FIG.

  As described above, the package 1 formed by injection molding using a molding die, such as the package 1 used in the light emitting device of the present embodiment, is prepared in the molding die and then provided inside the die. It is pushed out by a protruding member 25 such as a pin and removed from the mold.

  However, when the removal operation is performed, the molded member portion of the package still has heat and is easily deformed by external pressure. For example, if the lead electrode 2 main surface in the recess is a pin knock surface, the mechanical strength of the molded member is weak, so the holding force of the lead electrode 2 inserted in the inside is weak, and the displacement of the lead electrode 2 and the lead electrode 2 itself may be distorted, and the light emitting element 4 placed on the lead electrode 2 is disposed in an inclined state, and a directional characteristic shift occurs between the light emitting devices. Therefore, it is necessary to provide a pin knock surface on the surface of the package 1. In this case, if the light emitting device is to be downsized, the end portion of the package 1 must be a knock surface. However, when the package 1 is removed from the mold, it is still soft, and if it is knocked with a pin, a part of the molded member is pushed back into the mold. When this pin knock surface is the upper surface of the side wall that forms the recess, the pushed back molding material is directed toward the light reflecting surface formed on the side wall, so that the shape of the light reflecting surface is deformed, which adversely affects the optical characteristics of the light emitting device. There is a risk of

  On the other hand, the light-emitting device of the present embodiment has a first main surface 1a and a second main surface 1b in this order from the concave portion whose opening is the light-emitting surface toward the outside of the light-emitting device. By removing the package from the mold using the main surface 1b of the pin as a pin knock surface, the shape of the concave portion will not be deformed even when the package 1 is miniaturized. It can be formed with good properties.

  In the present embodiment, the shape of the second main surface 1b is not particularly limited, but preferably has a convex portion 1c on the second main surface 1b, and the height of the convex portion 1c is the first height. The height is preferably lower than the height to the main surface. Thereby, when fixing the light-emitting device of this invention to another member, a contact area with an adhesive agent etc. increases on the 2nd main surface 1b, and it can raise adhesive strength. Further, as shown in FIGS. 2 to 4, it is preferable that an outer peripheral wall having a hollow inside is formed by the convex portion 1c. As a result, when the internal cavity is filled with an adhesive and fixed to an optical member or the like, the outer wall prevents the adhesive from flowing out to the lead electrode or the first main surface 1a side. A light-emitting device having excellent characteristics can be formed. The shape having the convex portion 1c on the second main surface 1b not only provides a shape for forming the convex portion 1c on the inner wall surface of the convex die 27, but also presses the protruding member 25 against the second main surface 1b. By applying, it can be formed simultaneously with the step of taking out the package 1 (FIG. 16D).

  The package 1 of the present embodiment has a recess that can accommodate the light emitting element 4 and the light receiving element. The shape of the inner wall surface forming the recess is not particularly limited, but when the light emitting element 4 is placed, it is preferable to have a tapered shape so that the inner diameter gradually increases toward the opening. Thereby, the light emitted from the end face of the light emitting element 4 can be efficiently extracted in the direction of the light emission observation surface. Further, in order to enhance the reflection of light, the inner wall surface of the recess may be provided with a light reflection function such as metal plating such as silver.

  In the light emitting device of the present embodiment, the light emitting element 4 is placed in the concave portion of the package 1 configured as described above, and a light-transmitting resin is filled so as to cover the light emitting element 4 in the concave portion. The sealing member 3 is formed. Next, the manufacturing process and each component of the light emitting device according to this embodiment will be described in detail.

[Step 1: Lead electrode formation]
In this embodiment, first, as a first step, a metal plate is punched to form a lead frame having a plurality of pairs of positive and negative lead electrodes, and metal plating is applied to the surface of the lead frame. . A hanger lead for supporting the package from the lead electrode cut forming step to the light emitting device separation step can be provided on a part of the lead frame.

(Lead electrode 2)
The lead electrode 2 in the present embodiment is a conductor capable of supplying power to the light emitting element and mounting the light emitting element. In particular, the lead electrode 2 according to the present embodiment is integrally molded at the time of molding the package so that one end is inserted into the package from the side of the package and the other end protrudes from the side of the package. The main surface of the end portion of the lead electrode 2 inserted into the package can be integrally molded so as to be exposed from the bottom surface of the recess of the package by bringing a part of the molding die into contact with the lead electrode. In the semiconductor device configured such that the main surface of the end portion of the lead electrode 2 is not exposed from the bottom surface of the recess of the package, the connection between the semiconductor element placed in the recess and the lead electrode exposed outside the recess is conductive. This is done with a wire.

  The material of the lead electrode 2 is not particularly limited as long as it is conductive. However, the lead electrode 2 is required to have good adhesion and electrical conductivity to the conductive wires 5 and the bumps 6 that are members electrically connected to the semiconductor element. . The specific electric resistance is preferably 300 μΩ-cm or less, more preferably 3 μΩ-cm or less. Suitable materials that satisfy these conditions include iron, copper, iron-containing copper, tin-containing copper and copper, gold, silver plated aluminum, iron, copper, and the like.

  In the portion corresponding to each package of the long metal plate after press working, the positive lead electrode is a negative lead electrode so that one end surface thereof faces the one end surface of the negative lead electrode at the bottom surface of the concave portion after molding. And are separated. In this embodiment, the lead electrode 2 whose end principal surface is exposed at the bottom surface of the recess is not specially processed, but a molding resin is provided by providing at least one pair of through holes on the left and right with the longitudinal direction of the recess as an axis. It is also possible to increase the bond strength.

[Step 2: Package formation]
The package 1 according to the present embodiment can be mounted with the light emitting element 4 and functions as a support for fixing and holding the lead electrode 2 on which the light emitting element 4 is mounted. The light emitting element 4 and the conductive wire 5 can be removed from the external environment. It also has a function to protect.

  Subsequent to step 1, the long metal plate is placed between a convex mold and a concave mold, which are forming molds, and these molds are closed. At this time, the end portions of at least two lead electrodes are arranged in a cavity portion obtained by closing the convex and concave shapes. Next, a molding material is injected into the cavity from the gate provided on the concave back surface to cover the ends of at least two lead electrodes. The hollow portion corresponds to the outer shape of the package. In the present embodiment, the mold for molding the molded resin portion has a step on the package main surface adjacent to the recess, and is one step lower than the first main surface 1a and the first main surface 1a. The first main surface 1a has a shape such that a package 1 including the second main surface 1b disposed on the outer side from the recess is obtained. Further, in the forming die, it is preferable that the pressed long metal plate is inserted and disposed between the convex die and the concave die so that the punching direction of the press coincides with the direction of injecting the resin into the forming die. By determining the arrangement direction of the long metal plate in this way, the resin formed in the space formed by the end portions of the positive and negative lead electrodes can be filled without any gap, and on one main surface of the injected molding resin Can be prevented.

  Further, when the hanger lead described above is provided on the lead frame, as shown in FIG. 3A, the package 1 having a recess on the side surface of the package is formed by the shape of the tip of the hanger lead. The package can be supported using the recess.

(Molding material)
The molding material for the package used in the present invention is not particularly limited, and any conventionally known thermoplastic resin such as liquid crystal polymer, polyphthalamide resin, polybutylene terephthalate (PBT), or the like can be used. In particular, when a semi-crystalline polymer resin containing a high melting point crystal such as polyphthalamide resin is used, the surface energy is large, and a sealing resin that can be provided inside the opening or a light guide plate that can be retrofitted Thus, a package having good adhesion with the above can be obtained. Thereby, in the process of filling and curing the sealing resin, it is possible to suppress the occurrence of peeling at the interface between the package and the sealing resin during the cooling process. Moreover, in order to reflect the light from a light emitting element chip | tip efficiently, white pigments, such as a titanium oxide, can be mixed in a package shaping | molding member.

  The molded member thus formed is removed from the mold. Specifically, the concave mold is first opened, and then the pins provided inside the convex mold are projected toward the second main surface of the package. At this time, a cylindrical outer wall having the pin diameter as an inner wall is formed on the second main surface. By having such a cylindrical outer wall, when the light emitting device is fixed to another member with an adhesive or the like, the flow of the adhesive can be prevented, and the fixing force with the other member is improved.

[Step 3: Placement of semiconductor element]
Next, the semiconductor element is fixed to the lead electrode 2 exposed on the bottom surface of the recess provided in the package 1. In this embodiment, a light-emitting element is described as a semiconductor element. However, a semiconductor element that can be used in the present invention is not limited to a light-emitting element, and includes a light-receiving element, an electrostatic protection element (such as a Zener diode or a capacitor), Or what combined those 2 or more types can be used.

(Light emitting element 4)
As the semiconductor element in the present invention, semiconductor elements such as a light emitting element and a light receiving element are conceivable. The semiconductor element used in the present embodiment is an LED chip used as a light emitting element. A plurality of LED chips in the present embodiment may be used in accordance with the size of the bottom surface of the recess, and various shapes can be formed in accordance with the shape of the bottom surface of the recess.

Here, the light emitting device 4 is not particularly limited in the present invention, but when the fluorescent material 7 is used together, a semiconductor light emitting device having an active layer capable of emitting a wavelength capable of exciting the fluorescent material is preferable. Examples of such semiconductor light emitting devices include various semiconductors such as ZnSe and GaN, but nitride semiconductors (In _X Al _Y Ga _1- XYN capable of emitting short wavelengths capable of efficiently exciting fluorescent materials). , 0 ≦ X, 0 ≦ Y, X + Y ≦ 1). The nitride semiconductor may contain boron or phosphorus as desired. Examples of the semiconductor structure include a homostructure having a MIS junction, a PIN junction, and a pn junction, a heterostructure, or a double heterostructure. Various emission wavelengths can be selected depending on the material of the semiconductor layer and the degree of mixed crystal. Moreover, it can also be set as the single quantum well structure and the multiple quantum well structure which formed the active layer in the thin film which produces a quantum effect.

  When a nitride semiconductor is used, a material such as sapphire, spinel, SiC, Si, ZnO, or GaN is preferably used for the semiconductor substrate. In order to form a nitride semiconductor with good crystallinity with high productivity, it is preferable to use a sapphire substrate. A nitride semiconductor can be formed on the sapphire substrate by MOCVD or the like. For example, a buffer layer such as GaN, AlN, or GaAIN is formed on a sapphire substrate, and a nitride semiconductor having a pn junction is formed thereon. The substrate can also be removed after the semiconductor layer is laminated.

As an example of a light emitting device having a pn junction using a nitride semiconductor, a first contact layer formed of n-type gallium nitride, a first cladding layer formed of n-type aluminum nitride / gallium, and a nitride layer on a buffer layer Examples include a double hetero structure in which an active layer formed of indium gallium, a second cladding layer formed of p-type aluminum nitride / gallium, and a second contact layer formed of p-type gallium nitride are sequentially stacked. Nitride semiconductors exhibit n-type conductivity without being doped with impurities. When forming a desired n-type nitride semiconductor, for example, to improve luminous efficiency, it is preferable to appropriately introduce Si, Ge, Se, Te, C, etc. as an n-type dopant. On the other hand, when forming a p-type nitride semiconductor, the p-type dopants such as Zn, Mg, Be, Ca, Sr, and Ba are doped. Since nitride semiconductors are not easily converted to p-type by simply doping with a p-type dopant, it is preferable to reduce resistance by heating in a furnace or plasma irradiation after introducing the p-type dopant. After the electrodes are formed, a light emitting element made of a nitride semiconductor can be formed by cutting the semiconductor wafer into chips. Further, if an insulating protective film made of SiO ₂ or the like is formed by patterning so as to expose only the bonding portions of the electrodes and cover the entire element, a miniaturized light emitting device can be formed with high reliability. When white light is emitted in the light emitting diode of the present invention, the emission wavelength of the light emitting element is preferably 400 nm or more and 530 nm or less, taking into consideration the complementary color relationship with the emission wavelength from the fluorescent material, deterioration of the translucent resin, and the like. More preferably, it is 490 nm or less. In order to further improve the excitation and emission efficiency of the light emitting element and the fluorescent material, 450 nm or more and 475 nm or less are more preferable. Note that a light-emitting element having a main light emission wavelength in an ultraviolet region shorter than 400 nm or a short wavelength region of visible light can be used in combination with a member that is relatively difficult to be deteriorated by ultraviolet rays.

(Bump 6)
In the present embodiment, when the light emitting element 4 is mounted by a flip chip method in which a pair of electrodes provided on the same surface is opposed to a pair of lead electrodes exposed from the package recess, light is emitted to the light emitting surface. There is no blocking object, and uniform light emission can be obtained. The material of the bump is not particularly limited as long as it is conductive, but preferably contains at least one of the materials included in the positive and negative electrodes of the light emitting element and the plating material of the lead electrode. For example, Ag, Au, eutectic solder (Au—Sn), Pb—Sn, lead-free solder and the like can be mentioned. In this embodiment, bumps 6 made of Au are formed on each lead electrode 2, each electrode of the light emitting element 4 is made to face each bump, and heat, ultrasonic waves, and a load are applied to the bump and the electrode. And join. Alternatively, in another embodiment, first, bumps 6 are formed on each electrode of the light emitting element, and then each bump 6 and each lead electrode 2 are opposed to each other and similarly joined by ultrasonic waves. The types of bumps with different formation methods include stud bumps obtained by bonding the ends of conductive wires and then cutting the wires to leave the ends, and metal after applying the desired mask pattern. There are bumps obtained by vapor deposition. Further, such bumps can be provided first on the lead electrode side, or can be provided first on the electrode side of the light emitting element, or provided separately on the lead electrode and the electrode side of the light emitting element. You can also

  Moreover, when mounting by a flip-chip system, it is preferable that a semiconductor element is mounted via a submount as a support substrate. FIG. 7 shows a schematic perspective view of an embodiment mounted via a submount. In the flip chip method, the lead electrode is displaced due to the thermal stress of the package, so that the light emitting element and the lead electrode that are joined via the bump are easily separated. In addition, it is difficult to reduce the distance between the tip portions of the opposing positive and negative lead electrodes to the distance between the positive and negative electrodes of the light emitting element, and it is difficult to stably connect the light emitting element to the lead electrode. Although the above-mentioned problem is solved to some extent by optimizing the package material, further reliability improvement of the light-emitting device can be easily achieved by flip-chip mounting via the submount.

  On the surface of the submount substrate 11, a conductive pattern is disposed by a conductive member 12 from a surface facing the light emitting element 4 to a surface facing the lead electrode 2. It is also possible to provide the conductive pattern intervals so as to be narrowed to the interval between the positive and negative electrodes of the light emitting element 4 by a method such as etching. The material of the submount substrate 11 is preferably aluminum nitride with respect to the light emitting element 4 having substantially the same thermal expansion coefficient as that of the nitride semiconductor light emitting element. By using such a material, the influence of the thermal stress generated between the submount substrate 11 and the light emitting element 4 can be reduced. Alternatively, the material of the submount substrate 11 is preferably silicon, which can have the function of an electrostatic protection element (zener diode) inside and is inexpensive. At this time, the p-type and n-type semiconductors are exposed on the surface of the submount, and the electrodes provided on the p-type and n-type semiconductors are in reverse parallel to the negative electrode and the positive electrode of the light emitting element via bumps, respectively. Connected. The conductive member is preferably made of aluminum, silver, or gold having high reflectivity. Furthermore, it is preferable to provide a hole or a concavo-convex shape at a location where the mounting of the light emitting element 4 is not adversely affected on the submount substrate 11. By providing such a shape, the heat from the light emitting element 4 can be efficiently radiated from the submount. It is preferable to provide at least one through hole in the thickness direction of the submount substrate 11 and to form the conductive member 12 so as to extend on the inner wall surface of the through hole, since the heat dissipation is further improved. In the submount in this embodiment, the conductive pattern is directly connected to the lead electrode. However, the submount may be connected to the lead electrode through a conductive wire.

  In order to improve the reliability of the light emitting device, a gap formed between the positive and negative electrodes of the light emitting element and the submount, or between the positive and negative electrodes of the light emitting element and the lead electrode 2 exposed at the bottom of the recess of the package. May be filled with underfill. The underfill material is, for example, a thermosetting resin such as an epoxy resin. In order to relieve the thermal stress of underfill, aluminum nitride, aluminum oxide, a composite mixture thereof, or the like may be further mixed into the epoxy resin. The amount of underfill is an amount that can fill a gap formed between the positive and negative electrodes of the light emitting element and the submount.

  The conductive pattern provided on the submount and the electrode of the light emitting element 4 are connected by ultrasonic bonding using a bonding member 10 such as Au, eutectic solder (Au-Sn, Pb-Sn), lead-free solder, or the like. In addition, the conductive pattern provided on the submount and the lead electrode 2 are connected by a bonding member 10 such as an Au paste or an Ag paste.

(Conductive wire 5)
On the other hand, after the light emitting element 4 is die-bonded to one lead electrode, each electrode of the light emitting element and the lead electrode 2 may be connected by the conductive wire 5. Here, the bonding member used for die bonding is not particularly limited, and an insulating adhesive such as an epoxy resin, an Au—Sn alloy, a resin containing a conductive material, glass, or the like can be used. The conductive material contained is preferably Ag. When an Ag paste having an Ag content of 80% to 90% is used, a light emitting device having excellent heat dissipation and low stress after bonding can be obtained.

The conductive wire 5 is required to have good ohmic properties, mechanical connectivity, electrical conductivity and thermal conductivity with the electrode of the light emitting element 4. Preferably ^{0.01cal / (s) (cm 2} ) (℃ / cm) or higher as heat conductivity, and more preferably ^{0.5cal / (s) (cm 2} ) (℃ / cm) or more. In consideration of workability and the like, the diameter of the conductive wire is preferably Φ10 μm or more and Φ45 μm or less. In particular, the conductive wire is easily disconnected at the interface between the coating portion containing the fluorescent material and the sealing member not containing the fluorescent material. Even if the same material is used, it is considered that wire breakage is likely because the substantial amount of thermal expansion differs depending on the fluorescent material. Therefore, the diameter of the conductive wire is more preferably 25 μm or more, and more preferably 35 μm or less from the viewpoint of light emitting area and ease of handling. Specific examples of such conductive wires include conductive wires using metals such as gold, copper, platinum, and aluminum, and alloys thereof.

[Step 4: Sealing]
Next, a translucent sealing member 3 is provided to protect the light emitting element 4 from the external environment. The concave portion of the package 1 is filled with the material of the sealing member 3 so as to cover the light emitting element 4 or the conductive wire 5, and the light emitting element 4 is covered by curing.

(Sealing member 3)
The material of the sealing member 3 is not particularly limited as long as it is translucent. Silicone resin, epoxy resin, urea resin, fluororesin, and a hybrid resin including at least one of these resins are excellent in weather resistance. A light-sensitive resin can be used. The sealing member is not limited to an organic material, and an inorganic material having excellent light resistance such as glass and silica gel can also be used. In the present embodiment, any member such as a viscosity extender, a light diffusing agent, a pigment, a fluorescent substance, and the like can be added to the sealing member depending on the intended use. Examples of the light diffusing agent include barium titanate, titanium oxide, aluminum oxide, silicon oxide, silicon dioxide, heavy calcium carbonate, light calcium carbonate, and a mixture containing at least one of them. Furthermore, a lens effect can be provided by making the light emitting surface side of the sealing member have a desired shape, and light emitted from the light emitting element chip can be focused. In addition, when a light receiving element is used as a semiconductor element, it is possible to improve the sensitivity of the light receiving device if light that passes through the sealing member and enters the light receiving element is condensed in the direction of the light receiving element. It is. Specifically, a convex lens shape, a concave lens shape, an elliptical shape as viewed from the light emission observation surface, or a shape obtained by combining a plurality of them can be used.

(Fluorescent substance 7)
In the present invention, when a light-emitting element is used as a semiconductor element, an inorganic fluorescent substance or an organic fluorescent substance is present in and / or around each constituent member such as the light-emitting element, the sealing member, the die bond material, the underfill, and the package. Various fluorescent materials can be arranged. In addition, the fluorescent substance in the present embodiment is provided outside the sealing member so as to cover the light emission observation surface side surface of the sealing member, and is separated from the light emission observation surface side surface of the sealing member and the light emitting element. It is also possible to provide a layer containing a phosphor or a filter inside the sealing member at a certain position. As an example of such a fluorescent substance, there is a fluorescent substance containing a rare earth element which is an inorganic fluorescent substance described below.

As the rare earth element-containing fluorescent material, specifically, at least one element selected from the group of Y, Lu, Sc, La, Gd, Tb and Sm, and at least selected from the group of Al, Ga, and In A garnet (garnet) type phosphor having one element can be mentioned. In particular, the aluminum garnet phosphor used in the present embodiment includes Al and at least one element selected from Y, Lu, Sc, La, Gd, Tb, Eu, Ga, In, and Sm. And a phosphor activated by at least one element selected from rare earth elements, and is a phosphor that emits light when excited by visible light or ultraviolet light emitted from a light emitting element. For example, in addition to the yttrium aluminum oxide phosphor (YAG phosphor) described below, Tb _2.95 Ce _0.05 Al ₅ O ₁₂ , Y _2.90 Ce _0.05 Tb _0.05 Al ₅ O ₁₂ , Y _2.94 Ce _0.05 Pr _0.01 Al ₅ O ₁₂ , Y _2.90 Ce _0.05 Pr _0.05 Al ₅ O _{12, and the} like. Among these, particularly in the present embodiment, two or more kinds of yttrium / aluminum oxide phosphors containing Y and activated by Ce or Pr and having different compositions are used.

In addition, the nitride-based phosphor used in the present invention includes at least one element selected from Be, Mg, Ca, Sr, Ba, and Zn, and C, Si, Ge, Sn. , Ti, Zr, and Hf, and a phosphor activated with at least one element selected from rare earth elements. Furthermore, the nitride-based phosphor used in the present embodiment refers to a phosphor that emits light when excited by absorbing visible light, ultraviolet light, and light emitted from the YAG-based phosphor emitted from the light-emitting element. Examples of the nitride phosphor include (Sr _0.97 Eu _0.03 ) ₂ Si ₅ N ₈ , (Ca _0.985 Eu _0.015 ) ₂ Si ₅ N ₈ , (Sr _0.679 Ca _0.291). Eu _0.03 ) ₂ Si ₅ N ₈ , and the like. Hereinafter, each phosphor will be described in detail.

(Yttrium aluminum oxide phosphor)
The phosphor used in the light-emitting device of the present embodiment is yttrium activated by cerium that is excited by light emitted from a semiconductor light-emitting element having a nitride-based semiconductor as an active layer and can emit light of different wavelengths.・ Based on aluminum oxide phosphors. Specific examples of the yttrium / aluminum oxide fluorescent material include YAlO ₃ : Ce, Y ₃ Al ₅ O ₁₂ : Ce (YAG: Ce), Y ₄ Al ₂ O ₉ : Ce, and a mixture thereof. It is done. The yttrium / aluminum oxide phosphor may contain at least one of Ba, Sr, Mg, Ca, and Zn. Moreover, by containing Si, the reaction of crystal growth can be suppressed and the particles of the fluorescent material can be aligned. In this specification, the yttrium / aluminum oxide phosphor activated by Ce is to be interpreted in a broad sense, and a part or all of yttrium is selected from the group consisting of Lu, Sc, La, Gd and Sm. Or a part or the whole of aluminum is substituted with any one or both of Ba, Tl, Ga, and In, and is used in a broad sense including a fluorescent substance having a fluorescent action.

More specifically, the general formula _{(Y z Gd 1-z)} 3 Al 5 O 12: Ce ( where, 0 <z ≦ 1) photoluminescent fluorescent substance or the general formula represented by _{(Re 1-a Sm a)} 3 Re ' ₅ O ₁₂ : Ce (where 0 ≦ a <1, 0 ≦ b ≦ 1, Re is at least one selected from Y, Gd, La, and Sc, and Re ′ is selected from Al, Ga, and In. At least one kind of photoluminescent fluorescent material. Since this fluorescent material has a garnet (garnet-type) structure, it is resistant to heat, light and moisture, and the peak of the excitation spectrum can be made around 450 nm. The emission peak is also in the vicinity of 580 nm and has a broad emission spectrum that extends to 700 nm.

  Moreover, the photoluminescence fluorescent substance can increase the excitation light emission efficiency in a long wavelength region of 460 nm or more by containing Gd (gadolinium) in the crystal. As the Gd content increases, the emission peak wavelength shifts to a longer wavelength, and the entire emission wavelength also shifts to the longer wavelength side. That is, when a strong reddish emission color is required, it can be achieved by increasing the amount of Gd substitution. On the other hand, as Gd increases, the emission luminance of photoluminescence by blue light tends to decrease. Furthermore, in addition to Ce, Tb, Cu, Ag, Au, Fe, Cr, Nd, Dy, Co, Ni, Ti, Eu, Pr, and the like can be contained as desired.

  Further, when a part of Al in the composition of the yttrium / aluminum / garnet fluorescent material having a garnet structure is replaced with Ga, the emission wavelength can be shifted to the short wavelength side. On the other hand, when part of Y in the composition is replaced with Gd, the emission wavelength can be shifted to the longer wavelength side. When substituting a part of Y with Gd, it is preferable that the substitution with Gd is less than 10%, and the Ce content (substitution) is 0.03 to 1.0. If the substitution with Gd is less than 20%, the green component is large and the red component is small. However, by increasing the Ce content, the red component can be supplemented and a desired color tone can be obtained without lowering the luminance. With such a composition, the temperature characteristics of the fluorescent substance itself are good, and the reliability of the light emitting diode can be improved. In addition, when a photoluminescent fluorescent material adjusted so as to have a large amount of red component is used, it becomes possible to emit an intermediate color such as pink, and a light emitting device having excellent color rendering properties can be formed.

  Such a photoluminescent fluorescent material uses an oxide or a compound that easily becomes an oxide at a high temperature as a raw material for Y, Gd, Al, and Ce, and mixes them sufficiently in a stoichiometric ratio. Get. Alternatively, a mixed raw material obtained by mixing a coprecipitation oxide obtained by firing a solution obtained by coprecipitation of a solution obtained by dissolving a rare earth element of Y, Gd, and Ce in an acid in a stoichiometric ratio with oxalic acid and aluminum oxide. Get. An appropriate amount of fluoride such as barium fluoride or ammonium fluoride is mixed as a flux and packed in a crucible, and baked in air at a temperature range of 1350 to 1450 ° C. for 2 to 5 hours to obtain a baked product. Can be obtained by ball milling in water, washing, separating, drying and finally passing through a sieve.

  In addition, the firing includes a first firing step in which a mixture of a raw material and a flux mixed with a raw material of a fluorescent material is mixed in the atmosphere or in a weak reducing atmosphere, and a second firing step in which the mixture is performed in a reducing atmosphere. It is preferable to perform firing in two stages. Here, the weak reducing atmosphere refers to a weak reducing atmosphere set so as to include at least the amount of oxygen necessary in the reaction process of forming a desired fluorescent substance from the mixed raw material. By performing the first firing step until the formation of the fluorescent substance structure is completed, blackening of the fluorescent substance can be prevented and a decrease in light absorption efficiency can be prevented. In addition, the reducing atmosphere in the second firing step refers to a reducing atmosphere stronger than the weak reducing atmosphere. When firing in two stages in this way, a fluorescent material with high absorption efficiency at the excitation wavelength can be obtained. Therefore, when a light emitting device is formed using the fluorescent material thus formed, the amount of the fluorescent material necessary for obtaining a desired color tone can be reduced, and a light emitting device with high light extraction efficiency can be formed. Can do.

(Silicon nitride phosphor)
Alternatively, a fluorescent substance that is excited and emits light by absorbing visible light emitted from the light-emitting element, ultraviolet light, or visible light from another fluorescent substance can be used. Specifically, Sr—Ca—Si—N: Eu, Mn added, Ca—Si—N: Eu, Sr—Si—N: Eu, Sr—Ca—Si—O—N: Eu, Ca— Examples thereof include Si—O—N: Eu and Sr—Si—O—N: Eu silicon nitride phosphors. The basic constituent elements of this fluorescent substance are represented by the general formula L _X Si _Y N _{(2X / 3 + 4Y / 3)} : Eu or L _X Si _Y O _Z N _{(2X / 3 + 4Y / 3-2Z / 3)} : Eu (L is Sr, Ca, or any one of Sr and Ca.) In the general formula, X and Y are preferably X = 2, Y = 5, or X = 1, Y = 7, but any can be used.

More specifically, the basic constituent elements, Mn is added _{(Sr X Ca 1-X)} 2 Si 5 N 8: Eu, Sr 2 Si 5 N 8: Eu, Ca 2 Si 5 N 8: Eu, _{sr X Ca 1-X Si 7} N 10: Eu, SrSi 7 N 10: Eu, CaSi 7 N 10: it is preferable to use a fluorescent material represented by Eu, during composition of the phosphor, Mg , Sr, Ca, Ba, Zn, B, Al, Cu, Mn, Cr, and at least one selected from the group consisting of Ni and Ni may be contained. The mixing ratio of Sr and Ca can be changed as desired. In addition, by using Si for the composition, it is possible to provide an inexpensive fluorescent material with good crystallinity.

The alkali earth metal group silicon nitride as a base case of using Eu ²⁺ as an activator, O from Eu ₂ O _3, it is preferable to use a material obtained by removing out of the system. For example, it is preferable to use europium alone or europium nitride. However, this is not the case when Mn is added. When Mn is added, diffusion of Eu ²⁺ is promoted, and light emission efficiency such as light emission luminance, energy efficiency, and quantum efficiency can be improved. Mn is contained in the raw material, or Mn alone or a Mn compound is contained in the manufacturing process and fired together with the raw material. However, Mn is not contained in the basic constituent elements after firing, or even if contained, only a small amount remains compared to the initial content. This is probably because Mn was scattered in the firing step.

  In addition, having at least one selected from the group consisting of Mg, Sr, Ca, Ba, Zn, B, Al, Cu, Mn, Cr, O and Ni has a large particle size easily. In addition to forming a fluorescent material, the luminance of emitted light can be increased. Further, B, Al, Mg, Cr and Ni have an effect that afterglow can be suppressed.

  The nitride fluorescent material absorbs part of blue light and emits light in the yellow to red region. When such a nitride fluorescent material, a yellow light emitting fluorescent material, for example, a YAG fluorescent material, and a light emitting element that emits blue light are combined, yellow to red light is emitted into a warm white by mixing colors. A light emitting device is obtained. The light-emitting device that emits white mixed color light can increase the special color rendering index R9 to about 40 at a color temperature of about Tcp = 4600K.

Then, the fluorescent substance: While explaining the manufacturing method of _{((Sr X Ca 1-X} ) 2 Si 5 N 8 Eu), but is not limited to this manufacturing method. The fluorescent material contains Mn and O.

Raw materials Sr and Ca are pulverized. The raw materials Sr and Ca are preferably used alone, but compounds such as imide compounds and amide compounds can also be used. The raw materials Sr and Ca may contain B, Al, Cu, Mg, Mn, Al ₂ O ₃ or the like. The raw materials Sr and Ca are pulverized in a glove box in an argon atmosphere. Sr and Ca obtained by pulverization preferably have an average particle diameter of about 0.1 μm to 15 μm, but are not limited to this range. The purity of Sr and Ca is preferably 2N or higher, but is not limited thereto. In order to improve the mixed state, at least one of the metal Ca, the metal Sr, and the metal Eu can be alloyed, nitrided, pulverized, and used as a raw material.

The raw material Si is pulverized. The raw material Si is preferably a simple substance, but a nitride compound, an imide compound, an amide compound, or the like can also be used. For example, Si ₃ N ₄ , Si (NH ₂ ) ₂ , Mg ₂ Si, or the like. The purity of the raw material Si is preferably 3N or more, but Al ₂ O ₃ , Mg, metal borides (Co ₃ B, Ni ₃ B, CrB), manganese oxide, H ₃ BO ₃ , B ₂ O ₃ , Compounds such as Cu ₂ O and CuO may be contained. Si is also pulverized in a glove box in an argon atmosphere or a nitrogen atmosphere in the same manner as the raw materials Sr and Ca. The average particle size of the Si compound is preferably about 0.1 μm to 15 μm.

  Next, the raw materials Sr and Ca are nitrided in a nitrogen atmosphere. This reaction formula is shown in the following formula 1 and formula 2, respectively.

3Sr + N ₂ → Sr ₃ N ₂ (Formula 1)
3Ca + N ₂ → Ca ₃ N ₂ (Formula 2)
Sr and Ca are nitrided in a nitrogen atmosphere at 600 to 900 ° C. for about 5 hours. Sr and Ca may be mixed and nitrided, or may be individually nitrided. Thereby, a nitride of Sr and Ca can be obtained. Sr and Ca nitrides are preferably of high purity, but commercially available ones can also be used.

  Next, the raw material Si is nitrided in a nitrogen atmosphere. This reaction formula is shown in the following formula 3.

3Si + 2N ₂ → Si ₃ N ₄ (Formula 3)
Silicon Si is also nitrided in a nitrogen atmosphere at 800 to 1200 ° C. for about 5 hours. Thereby, silicon nitride is obtained. The silicon nitride used in the present invention is preferably highly pure, but commercially available ones can also be used.

Sr, Ca or Sr—Ca nitride is pulverized. Sr, Ca, and Sr—Ca nitrides are pulverized in a glove box in an argon atmosphere or a nitrogen atmosphere.
Similarly, Si nitride is pulverized. Similarly, the Eu compound Eu ₂ O ₃ is pulverized. Europium oxide is used as the Eu compound, but metal europium, europium nitride, and the like can also be used. In addition, an imide compound or an amide compound can also be used as the N raw material. Europium oxide is preferably highly purified, but commercially available products can also be used. The average particle size of the alkaline earth metal nitride, silicon nitride and europium oxide after pulverization is preferably about 0.1 μm to 15 μm.

The raw material may contain at least one selected from the group consisting of Mg, Sr, Ca, Ba, Zn, B, Al, Cu, Mn, Cr, O, and Ni. In addition, the above elements such as Mg, Zn, and B can be mixed by adjusting the blending amount in the following mixing step. These elements can be added alone to the raw material, but are usually added in the form of a compound. Such compounds include H ₃ BO ₃ , Cu ₂ O ₃ , MgCl ₂ , MgO · CaO, Al ₂ O ₃ , metal borides (CrB, Mg ₃ B ₂ , AlB ₂ , MnB), B ₂ O ₃ , Cu ₂ O, CuO, and the like.

After the pulverization, Sr, Ca, Sr—Ca nitride, Si nitride, and Eu compound Eu ₂ O ₃ are mixed, and Mn is added. Since these mixtures are easily oxidized, they are mixed in a glove box in an Ar atmosphere or a nitrogen atmosphere.

Finally, a mixture of Sr, Ca, Sr—Ca nitride, Si nitride, and Eu compound Eu ₂ O ₃ is fired in an ammonia atmosphere. By the firing, a fluorescent material represented by (Sr _X Ca _1-X ) ₂ Si ₅ N ₈ : Eu to which Mn is added can be obtained. However, the composition of the target fluorescent substance can be changed by changing the blending ratio of each raw material.

For firing, a tubular furnace, a small furnace, a high-frequency furnace, a metal furnace, or the like can be used. The firing temperature can be in the range of 1200 to 1700 ° C, but the firing temperature is preferably 1400 to 1700 ° C. It is preferable to use a one-step baking in which the temperature is gradually raised and the baking is performed at 1200 to 1500 ° C. for several hours, but the first baking is performed at 800 to 1000 ° C. and the heating is gradually started from 1200. Two-stage firing (multi-stage firing) in which the second stage firing is performed at 1500 ° C. can also be used. The raw material of the fluorescent material is preferably fired using a crucible or boat made of boron nitride (BN). Besides the crucible made of boron nitride, a crucible made of alumina (Al ₂ O ₃ ) can also be used.

  By using the above manufacturing method, it is possible to obtain a target fluorescent substance.

The fluorescent substance emits light reddish that can be used in the present embodiment is not particularly limited, for _{example, Y 2 O 2 S: Eu} , La 2 O 2 S: Eu, CaS: Eu SrS: Eu, ZnS: Mn, ZnCdS: Ag, Al, ZnCdS: Cu, Al and the like.

  The phosphors capable of emitting red light typified by aluminum garnet phosphors and nitride phosphors formed as described above are formed in a single phosphor layer around the light emitting element. Two or more types may be present, or one type or two or more types may be present in the phosphor layer composed of two layers. The phosphor layer is formed by potting or stencil printing using a translucent inorganic member such as translucent resin or glass as a binder. Further, a method of forming after the semiconductor light emitting element is fixed to the support, a method of forming the semiconductor light emitting device after forming it in a semiconductor wafer state, or a method of using these methods in combination is employed. With such a configuration, it is possible to obtain mixed color light by mixing light from different types of phosphors. In this case, it is preferable that the average particle diameters and shapes of the phosphors are similar in order to better mix the light emitted from the phosphors and reduce color unevenness. In addition, the nitride-based phosphor is disposed at a position closer to the light-emitting element than the YAG-based phosphor in consideration of absorbing part of the light whose wavelength has been converted by the YAG-based phosphor. It is preferable to do so. With this configuration, a part of the light wavelength-converted by the YAG phosphor is not absorbed by the nitride phosphor, and the YAG phosphor and the nitride phosphor are mixed. Compared with the case where it is contained, the color rendering properties of mixed color light can be further improved.

(Alkaline earth metal halogen apatite fluorescent substance)
In addition, an element represented by M including at least one selected from Mg, Ca, Ba, Sr, and Zn, and an M ′ including at least one selected from Mn, Fe, Cr, and Sn are represented. An alkaline earth metal halogen apatite fluorescent material activated by Eu having an element can be used, and a light emitting device capable of emitting white mixed light with high luminance can be obtained with high productivity. In particular, an alkaline earth metal halogen apatite fluorescent material activated with Eu containing at least Mn and / or Cl is excellent in light resistance and environmental resistance. In addition, the emission spectrum emitted from the nitride semiconductor can be efficiently absorbed. Further, the white region can emit light, and the region can be adjusted by the composition. Further, it can emit yellow and red light with high brightness by absorbing the ultraviolet region of a long wavelength. Therefore, a light emitting device with excellent color rendering can be obtained. Needless to say, alkaline earth metal chloroapatite fluorescent materials are included as examples of alkaline earth metal halogen apatite fluorescent materials. In the alkaline earth metal halogen apatite fluorescent material, when the general formula is represented by (M _1-xy Eu _x M ′ _y ) ₁₀ (PO ₄ ) ₆ Q ₂ (where M is Mg, Ca, At least one selected from Ba, Sr, Zn, M ′ is at least one selected from Mn, Fe, Cr, Sn, Q is at least one selected from halogen elements F, Cl, Br, and I 0.0001 ≦ x ≦ 0.5 and 0.0001 ≦ y ≦ 0.5), and a light emitting device capable of emitting mixed color light with high productivity is obtained.

In addition to the alkaline earth metal halogen apatite fluorescent material, BaMg ₂ Al ₁₆ O ₂₇ : Eu, (Sr, Ca, Ba) ₅ (PO ₄ ) ₃ Cl: Eu, SrAl ₂ O ₄ : Eu, ZnS: Cu, Zn ₂ GeO ₄ : Mn, BaMg ₂ Al ₁₆ O ₂₇ : Eu, Mn, Zn ₂ GeO ₄ : Mn, Y ₂ O ₂ S: Eu, La ₂ O ₂ S: Eu, Gd ₂ O ₂ S: Eu When at least one fluorescent material selected from the above is included, more detailed color tone can be adjusted, and white light with high color rendering can be obtained with a relatively simple configuration. Furthermore, the above-mentioned fluorescent substance can contain Tb, Cu, Ag, Au, Cr, Nd, Dy, Co, Ni, Ti, Pr, etc. in addition to Eu as desired.

  The particle size of the fluorescent material used in the present invention is preferably in the range of 1 μm to 100 μm, more preferably in the range of 10 μm to 50 μm, and even more preferably in the range of 15 μm to 30 μm. A fluorescent material having a particle size of less than 15 μm is relatively easy to form an aggregate, and is densely settled in a liquid resin, thus reducing the light transmission efficiency. In the present invention, by using such a fluorescent material that does not have a fluorescent material, concealment of light by the fluorescent material is suppressed and the output of the light emitting device is improved. In addition, the fluorescent material having a particle size range of the present invention has high light absorption and conversion efficiency and a wide excitation wavelength range. Thus, by including a large particle size fluorescent material having optically excellent characteristics, light around the dominant wavelength of the light emitting element can be converted and emitted well, and the mass productivity of the light emitting device is improved. Is done.

  Here, in the present invention, the particle size is a value obtained from a volume-based particle size distribution curve. The volume-based particle size distribution curve is obtained by measuring the particle size distribution by a laser diffraction / scattering method. Specifically, in an environment of an air temperature of 25 ° C. and a humidity of 70%, hexametalin having a concentration of 0.05%. Each substance was dispersed in an aqueous sodium acid solution and measured with a laser diffraction particle size distribution analyzer (SALD-2000A; manufactured by Shimadzu Corporation) in a particle size range of 0.03 μm to 700 μm. In the present specification, the particle size value when the integrated value is 50% in this volume-based particle size distribution curve is referred to as the center particle size, and the center particle size of the fluorescent material used in the present invention is in the range of 15 μm to 50 μm. Is preferred. Moreover, it is preferable that the fluorescent substance which has this center particle size value is contained frequently, and the frequency value is preferably 20% to 50%. In this way, by using a fluorescent material with small variation in particle size, a light emitting device having a favorable color tone with suppressed color unevenness can be obtained. The fluorescent material preferably has a shape similar to that of the diffusing agent used in the present invention. In the present specification, the similar shape means a circularity representing the degree of approximation of each particle size with a perfect circle (circularity = perimeter length of a perfect circle equal to the projected area of the particle / perimeter length of the projected particle). The difference between the values is less than 20%. Thereby, the diffusion of light by the diffusing agent and the light from the excited fluorescent substance are mixed in an ideal state, and more uniform light emission is obtained.

[Step 5: Separate for each light emitting device]
Next, the connection portion from the lead frame to each lead electrode is cut and separated into individual light emitting devices. It is also possible to use a hanger lead that supports the package by the side recess 9 provided on the outer wall of the package. At this time, after forming described below, the support by the hanger lead is removed to obtain a package 1 as shown in FIG. By using the hanger leads, the forming process can be performed for each pair of lead electrodes, so that the number of semiconductor device formation processes can be reduced and the workability can be improved.

[Step 6: Forming of lead electrode 2]
Next, the positive and negative lead electrodes protruding from the end face of the package 1 are bent along the side face of the package 1 to form a J-bend type connection terminal portion. Here, the connection terminal portion of the lead electrode 2 refers to a portion of the lead electrode that can contact and be electrically connected to the conductive pattern of the mounting substrate.

  In the present embodiment, when the positive lead electrode and the negative lead electrode protrude from the end surface on the short axis side of the package main surface, the protruding portion is bent toward the back surface facing the main surface of the package (for example, FIG. 1 (a)) is preferable, and this allows the light emitting device to be mounted on the wiring board without adversely affecting mounting solder or the like on the light emitting surface side. The pair of positive and negative lead electrodes 2 are inserted so as to protrude from the end surface on the major axis side of the main surface of the package 1, and the protruding portion of the lead electrode 2 is bent toward a surface perpendicular to the light emitting surface (for example, FIG. 4 (a)) and the contact area between the connecting terminal portion of the lead electrode and the conductive pattern provided on the mounting substrate can be increased to ensure electrical connection, and the mounting accuracy can be increased. In addition, when the light emitting device is temporarily mounted on the mounting substrate and the reflow process is performed, the light emitting device can be prevented from rising from the temporary mounting surface. In this way, when the lead electrode is bent to form the connection terminal portion, it is preferable that the wall surface on the mounting surface side of the molded member and the exposed surface of the lead electrode are located on substantially the same plane. This is because the light emitting device can be stably mounted on the mounting substrate. Note that the structure of the connection terminal portion of the present invention is not limited to the J-bend type, and may be another structure such as a gull wing type. In the present embodiment, it is preferable that the periphery of the side surface of the package where the lead electrode protrudes is molded into a tapered shape with a predetermined angle as shown in FIGS. Accordingly, the connection terminal portion of the lead electrode 2 is arranged at a desired position in consideration of stable mounting of the light emitting device by bending the lead electrode 2 to the very side with the influence of elasticity of the lead electrode 2 taken into consideration. Can be easily done.

  Through the above process, the light-emitting device of this embodiment is manufactured. Furthermore, the light emitting device according to the embodiment produced as described above is arranged at a predetermined interval on a wiring board in which external electrodes are wired on the board, and is electrically connected. The substrate member of the wiring substrate is preferably excellent in thermal conductivity, and an aluminum base substrate, a ceramic base substrate, or the like can be used. In addition, when using a glass epoxy substrate or paper phenol substrate with poor thermal conductivity, it is preferable to take heat dissipation measures such as a thermal pad and a thermal via. Further, the light emitting diode and the wiring board can be electrically connected by a conductive member such as solder. In consideration of heat dissipation, it is preferable to use a silver paste.

(Translucent member)
The semiconductor device of the present invention is provided with a light-emitting surface side or a light-incident side that accurately fits the shape of the light incident part of a light-transmitting member made of a rigid light-transmitting resin or glass such as a lens or a light guide plate. be able to. Here, in this specification, the “light entrance / exit part” is provided for a translucent member that guides light from the semiconductor device or light to the semiconductor device in a desired direction. A portion where light is incident (particularly referred to as “light incident portion”) or a portion where light is emitted to the semiconductor device (particularly referred to as “light exit portion”).

  The translucent member in the present embodiment is a member that uses light reflection or refraction to guide light from a light emitting device incident in the member in a predetermined direction and to have a predetermined light distribution. A member that emits light to the outside. Moreover, the translucent member in another embodiment condenses the light from the outside of the light receiving device incident on the member in the direction of the light receiving element.

  In particular, in this embodiment, the translucent member used in the light emitting device has a light incident part that individually introduces light from the light emitting device. The inner wall of the light incident part has at least a first mounting surface in contact with the first main surface of the light emitting device according to the present embodiment and a second mounting surface in contact with the second main surface. Further, the light incident portion can be provided with a shape that can be fitted to the notch 13 provided on the main surface of the light emitting device.

  As described above, the present invention has a molded member that can always have a substantially constant shape, and by providing the molded member with a shape that can be positioned with another translucent member, the light source has a desired optical characteristic with a high yield. Can be formed.

(Surface light source)
The light source including the light guide plate and the light emitting device can be a planar light source that emits light incident from the light incident portion provided on the side surface of the light guide plate from the other side surface.

  The light guide plate in the present embodiment is a plate-like shape that guides light from a light emitting device incident on a member in a predetermined direction and emits the light from a predetermined surface to the outside of the member by utilizing reflection of light on the inner wall of the member. It is a translucent member. In particular, the light guide plate in the present embodiment refers to a plate-like light guide having a light exit surface that can be used as a planar light source such as a liquid crystal backlight.

  The material of the light guide plate is preferably excellent in light transmittance and moldability, and organic members such as acrylic resin, polycarbonate resin, amorphous polyolefin resin, and polystyrene resin, and inorganic members such as glass can be used. . The surface of the light guide plate preferably has a surface accuracy Ra of 25 μm (see JIS standard) or less in order to improve the transmittance and the total reflected light rate.

  Such a light guide plate is mounted such that the mounting surface provided in the light incident portion faces the main surface of the light emitting device. The light guide plate mounting method can be selected according to the specifications and requirements, such as screwing, bonding, welding, etc., which can be easily positioned and can ensure the bonding strength. In the embodiment, the second main surface of the package and the end surface of the light guide plate are fixed with an adhesive. Further, the planar light source of the present invention can be provided with a diffusion sheet on the upper side. Thus, the planar light source of the present invention can also be used as a direct backlight light source that irradiates other members such as a diffusion sheet disposed above. The selection of the diffusion sheet affects the film thickness and performance of the light guide plate. Therefore, it is preferable to verify and select each time according to specifications and requirements. In this example, a diffusion sheet having a haze value of 88% to 90% (see JIS standard) and a film thickness of about 100 μm is used for a light guide plate made of polycarbonate having excellent heat resistance and a film thickness of 20 mm. Thereby, the space | interval of the dot of each light source is relaxed, and uniform light emission is obtained. Such a diffusion sheet can be attached to the light guide plate directly by adhesion or welding. When a cover lens is provided above, it can be fixed by being sandwiched between the cover lens and the light guide plate. The distance between the diffusion sheet and the light guide plate is preferably 0 mm to 10 mm, and most preferably these interfaces are in close contact. The material of the diffusion sheet is mainly PET, but is not particularly limited as long as it is a material that does not deform or deteriorate due to the heat generated by the light emitting diode.

  The planar light-emitting light source thus obtained can emit light with uniformity and high brightness over the entire light-emitting surface. Examples according to the present invention will be described in detail below. Needless to say, the present invention is not limited to the following examples.

FIG. 1 shows a surface mount (SMD) type light emitting device according to this example. The light-emitting element 4 uses a nitride semiconductor element having a 475 nm In _0.2 Ga _0.8 N semiconductor having a monochromatic emission peak of visible light as an active layer. More specifically, the LED chip as the light-emitting element 4 is obtained by flowing TMG (trimethylgallium) gas, TMI (trimethylindium) gas, nitrogen gas and dopant gas together with a carrier gas onto a cleaned sapphire substrate by MOCVD. It can be formed by depositing a nitride semiconductor. A layer to be an n-type nitride semiconductor or a p-type nitride semiconductor is formed by switching between SiH ₄ and Cp ₂ Mg as the dopant gas.

FIG. 8 shows a plan view of the LED chip in the present embodiment, and FIG. 9 shows a cross-sectional view taken along a broken line AA ′ in FIG. As the element structure of the LED chip of this embodiment, a GaN layer that is an undoped nitride semiconductor, an n-type GaN layer that becomes an n-type contact layer 16 on which an Si-doped n-type electrode is formed, and an undoped structure. The active layer 17 is formed by laminating five sets of GaN layers, which are nitride semiconductors, and then GaN layers to be barrier layers and InGaN layers to be well layers, and finally GaN layers to be barrier layers. It has a multi-quantum well structure. An AlGaN layer and a p-type GaN layer which is a p-type contact layer 19 doped with Mg are sequentially laminated on the active layer 17 as a p-type cladding layer 18 doped with Mg. (Note that a GaN layer is formed on the sapphire substrate 14 at a low temperature to serve as the buffer layer 15. Also, the p-type semiconductor is annealed at 400 ° C. or higher after film formation.)
Etching exposes the surfaces of p-type contact layer 19 and n-type contact layer 16 on the same side as the nitride semiconductor on the sapphire substrate. Next, sputtering using Rh and Zr as materials is performed on the p-type contact layer to provide a diffusion electrode 20 having a pattern as shown in FIG. The diffusion electrode 20 includes a stripe that extends in the direction of the outer edge of the LED chip from the position where the p-side pedestal electrode 21 is formed, and a stripe that branches in the middle of the stripe and extends in the direction of the outer edge of the LED chip. More specifically, the diffusion electrode 20 in the present embodiment extends from the formation position substantially parallel to two sides adjacent to each other in the vicinity of the formation position of the p-side pedestal electrode 21 and forming the outer edge of the LED chip. Two pairs of stripes, a portion extending from the formation position so as to follow the diagonal direction (AA ′ direction) of the LED chip, and a direction branching in the middle of the extending portion and being substantially parallel to the two sides And a stripe having a portion to be stretched. By setting it as such a diffusion electrode 20, the electric current which flows through the diffusion electrode 20 can be spread over a wide range on the p-type contact layer 19, and the luminous efficiency of an LED chip can be improved.

  Further, sputtering using W, Pt, and Au as materials is performed, and a part of the diffusion electrode 20 and the n-type contact layer 16 are stacked in the order of W / Pt / Au, respectively, and the p-side pedestal electrode 21 and the n-side pedestal electrode are stacked. 22 are formed simultaneously. Here, by forming the p-side pedestal electrode 21 and the n-side pedestal electrode 22 at the same time, the number of steps for forming the electrodes can be reduced.

  Instead of the diffusion electrode 20, a metal thin film such as ITO (complex oxide of indium (In) and tin (Sn)) or Ni / Au is formed as a translucent electrode on the entire surface of the p-type nitride semiconductor. Then, the p-side pedestal electrode 21 may be formed on a part of the translucent electrode.

  A scribe line is drawn on the completed semiconductor wafer and then divided by an external force to form an LED chip (light refractive index of 2.5) which is a semiconductor light emitting element.

  A long metal plate made of iron-containing copper having a thickness of 0.15 mm is punched to form a lead frame having a plurality of pairs of positive and negative lead electrodes 2 inserted into each package. Further, Ag plating is applied to the surface of the lead frame in order to improve the light reflectance.

  Next, a molten polyphthalamide resin is poured and cured from a gate corresponding to the lower surface side of the package 1 into a molding die closed with a pair of positive and negative lead electrodes 2 inserted therein, and the package shown in FIG. Form. The package 1 has a recess capable of accommodating the light emitting element, and the positive and negative lead electrodes are integrally formed so that one main surface is exposed from the bottom surface of the recess. Further, the main surface side of the package 1 has a step on the main surface of the side wall portion, and has a first main surface 1a and a second main surface 1b from the concave portion formed by the inner wall surface 8 of the package. Yes. In addition, each of the lead electrodes 2 protruding from the side surface of the package, which is the short side of the light emitting surface, is bent toward the inside of the light emitting device on the back surface side facing the package main surface to form a connection terminal portion.

  The LED chip is bonded and fixed to the main surface of the end portion of the lead electrode 2 exposed on the bottom surface of the concave portion of the package 1 formed in this manner using epoxy resin as a die bond material. Next, the fixed electrode of the LED chip and each lead electrode 2 exposed from the bottom of the recess of the package 1 are connected by a conductive wire 5 made mainly of Au.

  Next, the sealing member 3 is formed. First, light calcium carbonate (refractive index of 1.62) having an average particle diameter of 1.0 μm and an oil absorption of 70 ml / 100 g as a diffusing agent is applied to 100 wt% of the phenylmethyl silicone resin composition (refractive index of 1.53). 3 wt% is contained, and the mixture is stirred for 5 minutes with a rotation and revolution mixer. Next, in order to cool the heat generated by the stirring treatment, the resin is allowed to stand for 30 minutes to return to room temperature and stabilized.

  The curable composition thus obtained is filled into the recesses of the package 1 up to the same plane line as the upper surfaces of both ends of the recesses. Finally, heat treatment is performed at 70 ° C. × 3 hours and 150 ° C. × 1 hour. As a result, a light emitting surface having a smooth recess in a substantially parabolic shape from the upper surface to the center of both end portions of the recess is obtained. Moreover, the sealing member 3 made of a cured product of the curable composition has a first layer having a large content of the diffusing agent and a content of the diffusing agent less than or not contained in the first layer. It is separated into two layers, the second layer, and the surface of the LED chip is covered with the first layer. Furthermore, the first layer is preferably formed continuously from the bottom surface of the recess to the surface of the LED chip. Thereby, the light emitted from the LED chip can be efficiently extracted to the outside, and good light uniformity can be obtained.

  In the light emitting device thus obtained, the first main surface and the second main surface are provided in a fixed shape on the main surface of the package on the light emitting surface side. Any member such as a support or an optical member can be mounted with high accuracy.

  2, 3 and 4 show a semiconductor device according to this example. In Example 1, a semiconductor device is formed in the same manner except that a circumferential outer wall is provided on the second main surface 1 b of the package 1.

  In the semiconductor device according to the present example, when the adhesive is injected into the outer peripheral wall and bonded to another member, the adhesive does not flow out of the outer peripheral wall (particularly, in the recess), and thus has excellent fixing force. It is a highly reliable semiconductor device.

  2, 3 and 4 show a semiconductor device according to this example. Other than the embodiment, except that the Au bump is formed on each electrode of the LED chip, and the flip chip mounting is carried out so as to face each lead electrode exposed from the bottom surface of the recess of the package by ultrasonic bonding. Similarly, a light emitting device is formed.

  The light emitting device according to this embodiment not only has the same effect as the above embodiment, but also has the electrode formation surface of the semiconductor light emitting element as a mounting surface for the lead electrode, and light is extracted from the element substrate side. This is a light emitting device with improved heat dissipation and light extraction efficiency compared to a light emitting device having a mounting surface on the side.

  2, 3 and 4 show the light emitting device according to this example. In Example 3, a light emitting device is formed in the same manner except that the fluorescent material is contained in the sealing member.

The fluorescent material is prepared by co-precipitation with oxalic acid of a solution obtained by dissolving a rare earth element of Y, Gd, and Ce in an acid at a stoichiometric ratio with oxalic acid, and calcining the mixture, and then mixing aluminum oxide. To obtain mixed raw materials. Further, barium fluoride is mixed as a flux, then packed in a crucible, and fired in air at a temperature of 1400 ° C. for 3 hours to obtain a fired product. The fired product is ball _milled in water, washed, separated, dried, and finally passed through a sieve to have a center particle size of 8 μm (Y _0.995 Gd _0.005 ) _2.750 Al ₅ O ₁₂ : Ce _0.250 phosphor Form.

  The silicone resin composition (refractive index: 1.53) is contained in 5.5 wt% of the fluorescent material (refractive index: 1.84), and the mixture is stirred for 5 minutes using a rotation and revolution mixer. The curable composition thus obtained is filled in the package recess to the same plane as the upper surfaces of both ends of the recess. Finally, heat treatment is performed at 70 ° C. × 2 hours and 150 ° C. × 1 hour.

  Accordingly, a light-emitting device capable of emitting mixed-color light of light emitted from the light-emitting element and fluorescence of a fluorescent material that absorbs the light and emits light having different wavelengths can be obtained. In addition, a light emitting surface having a substantially symmetrical parabolic recess from the upper surface to the center of both ends of the recess is obtained, and when combined with a light guide plate, light can be efficiently incident on the light guide plate.

  Except for exposing the positive and negative lead electrodes from the side surface of the package, which is the long axis side of the light emitting surface, and bending the exposed portion to the surface side perpendicular to the light emitting surface (for example, as shown in FIG. 4A). A light emitting device is formed in the same manner as in other embodiments. The light emitting device according to this example can be mounted on the mounting substrate with high stability.

  As shown in FIG. 5, a light emitting device is formed in the same manner as in the other examples except that a notch 13 is provided at one end of the first main surface facing each other. Furthermore, a shape that can be fitted to the notch 13 provided on the main surface of the light emitting device is provided on the mounting surface of the translucent member that faces the main surface of the light emitting device according to the present embodiment. The light emitting device according to the present embodiment can further increase the adhesion force and mounting accuracy with other members such as a translucent member.

  FIG. 10 is a schematic perspective view showing an embodiment of the planar light source in this embodiment, and FIG. 11 is a sectional view. In FIG. 10, the shaded portion is indicated by a dotted line.

  The planar light source in this embodiment includes a light emitting device 32 formed in the same manner as in the other embodiments, and a light guide plate 31 that is a translucent member made of acrylic resin. The light guide plate 31 has a light incident portion 34 for individually introducing light from the plurality of light emitting devices 32 into the light guide plate on one side, and uses reflection on the inner wall surface of the light guide plate on the other side. Light is irradiated in a planar shape from the provided light exit surface 35. One side surface for introducing light into the light guide plate includes a wall surface of the light incident portion 34 and a first mounting surface 33a adjacent to the wall surface of the light incident portion 34 and facing the first main surface 1a of the light emitting device 32. The second mounting surface 33b faces the second main surface 1b. Note that a prism shape (not shown) may be provided on the wall surface of the light incident portion 34 so that light from the light emitting device enters the light guide plate in a wide range.

  As described above, the planar light source according to the present embodiment is a molded member in which the package of the light emitting device can always have a substantially constant shape. By providing the molded member with a shape that can be positioned with the light guide plate, reliability and It is a planar light source with excellent wearability.

  The semiconductor light emitting device in this example will be described with reference to FIGS. FIG. 12 is a plan view of the semiconductor light emitting device in this example as seen from the electrode forming surface side. FIG. 13 is a cross-sectional view of the vicinity of the p-side pedestal electrode 21 taken along the broken line XX in FIG. 12, and shows the semiconductor stacked structure in the first region where the p-side pedestal electrode 21 is provided and the second region. The positional relationship with the provided convex part 23 is shown.

  In the semiconductor light emitting device of this example, the p-side pedestal electrode 21 and the n-side pedestal electrode 22 are provided on the same surface side, and light is extracted from the surface side on which these electrodes are formed. As in the other embodiments, the semiconductor multilayer structure constituting the semiconductor light emitting device includes a GaN buffer layer 15, a non-doped GaN layer, a Si-doped GaN layer that becomes the n-type contact layer 16, and an n-type cladding layer on the sapphire substrate 14. The Si-doped GaN layer, the InGaN layer serving as the active layer 17, the Mg-doped AlGaN layer serving as the p-type cladding layer 18, and the Mg-doped GaN layer serving as the p-type contact layer 19 have a layered structure. Further, the Mg-doped GaN layer, Mg-doped AlGaN layer, InGaN layer, Si-doped GaN layer, and Si-doped GaN layer are partially removed by etching or the like, and the n-side pedestal electrode 22 is formed on the exposed surface of the Si-doped GaN layer. The p-side pedestal electrode 21 is provided on the Mg-doped GaN layer. The n-side pedestal electrode 22 is formed by laminating W, Pt, and Au sequentially from the n-type contact layer side. The diffusion electrode 20 on which the p-side pedestal electrode 21 is formed is formed on almost the entire surface of the p-type contact layer, and Ni and Au are laminated in order from the p-type contact layer side (or an alloy of Ni and Au). As with the n-side electrode, the p-side pedestal electrode 21 is formed by laminating W, Pt, and Au. Further, in order to secure a light emitting region, the diffusion electrode 20 partially surrounds the n-side pedestal electrode 22.

  Here, the n-type contact layer 16 includes a first region provided with a semiconductor multilayer structure having the p-side pedestal electrode 21 and a second region different from the first region, as viewed from the electrode forming surface side. The n-side pedestal electrode 22 and a plurality of protrusions 23 are provided in the second region. As shown in FIG. 13, the top of each protrusion 23 provided in the second region is located closer to the p-type contact layer 19 than the active layer 17 in the cross section of the semiconductor light emitting device. That is, the top of the convex portion 23 is formed to be higher than the active layer 17. Since the semiconductor light emitting device of this embodiment has a DH structure, the top of the protrusion 23 only needs to be higher than the interface between at least the active layer 17 and the n-type semiconductor layer adjacent thereto, but the active layer 17 and p adjacent thereto are sufficient. More preferably, it is higher than the interface with the mold semiconductor layer.

  With this configuration, the light emitted from the active layer 17 in the end surface (side surface) direction hits the convex portion 23, and the traveling direction of the light can be changed to, for example, the observation surface side that is the electrode formation surface side. it can. Further, the light emitted from the end face to the outside of the side surface is scattered by the plurality of convex portions 23, and as a result, it is possible to effectively extract the light and control the directivity of the light. Furthermore, the light guided in the n-type contact layer 16 is irregularly reflected at the root of the convex portion 23 (the connection portion between the n-type contact layer 16 and the convex portion 23), and the light can be extracted effectively. Further, light can be taken into the convex portion 23 from the n-type contact layer 16, and light can be emitted to the outside again from the top of the convex portion 23 or an intermediate portion thereof. In particular, the semiconductor light emitting device in this embodiment can change the traveling direction of the light directly emitted from the active layer 17 in the end face (side face) direction to the light emission observation surface side by the convex portion 23, so Sex control can be performed effectively.

  Further, the above effect is obtained by inclining the convex portion 23 so that the width of the convex portion 23 becomes gradually narrower in the cross section of the convex portion, that is, from the n-type contact layer 16 side to the p-type contact layer 19 side. It will be big. That is, by intentionally forming an angle on the side surface of the convex portion 23, the light from the active layer 17 is totally reflected on the side surface of the convex portion 23, or the light guided through the n-type contact layer 16 is scattered. As a result, it is possible to effectively extract light to the emission observation surface side. The inclination angle of the convex portion 23 is preferably 40 ° to 80 °, then 50 ° to 75 °, and more preferably 60 ° to 65 °. The same applies to the case where the convex section has a trapezoidal shape.

  In addition, it is preferable that the convex portion 23 has substantially the same inclination angle on the side closer to the first region and the inclination angle on the far side. Although the reason for this is not clear, it is considered that uniform light extraction (control of light directivity) is possible as a whole because the inclination angles are the same. The inclination angle is preferably formed in the range described above.

  Furthermore, it is preferable that the convex section has a trapezoidal shape, that is, the convex portion itself has a truncated cone shape. With this configuration, the directivity control of light becomes easier, and more uniform light extraction as a whole becomes possible. When light is extracted from the p-type contact layer 19 side and the p-side contact layer 19 is used as an observation surface, it is considered that this effect can be obtained when the observation surface side of the convex portion 23 includes a plane without including a vertex. It is done.

  Moreover, when the shape of the cross section of the convex portion is a trapezoid, a concave portion can be further provided on the upper side (p side) of the trapezoid. Thereby, when the light guided through the n-type contact layer enters the inside of the convex portion, the concave portion formed at the top of the convex portion is preferable because light is easily emitted to the observation surface side.

  Furthermore, the semiconductor element in this example has at least two or more, preferably three or more protrusions in a direction substantially perpendicular to the emission end face of the semiconductor multilayer structure formed in the first region of the n-type contact layer 16. It is preferable that they are partially overlapped. Thereby, since the light emitted from the first region passes through the convex portion 23 with high probability, the above effect can be obtained more easily.

  The convex portion 23 in this embodiment is preferably formed simultaneously with the step of exposing the n-type contact layer 16 when the n-side pedestal electrode 22 is formed. That is, since the semiconductor light emitting device in this example has a structure including the p-side and n-side electrodes on the same surface side, after stacking up to the p-type contact layer on the substrate, at least from the p side of the semiconductor multilayer structure. It is necessary to remove the region corresponding to the n-side electrode so that the n-type contact layer is exposed. Specifically, for example, after the p-type contact layer 19 is laminated, a resist film is applied and exposed to a desired pattern, the remaining resist film is used as a mask, and a portion (first region) where a p-side electrode is provided later ) And the portion where the convex portion 23 is to be formed (a part of the second region) are removed by etching or the like until the n-type contact layer 22 is exposed. Thereby, since the exposed surface which forms an n side electrode can be formed and the convex part 23 can be formed simultaneously, it becomes possible to simplify a process.

  The convex portion 23 formed as described above has the same stacked structure as the semiconductor stacked structure in the first region. However, although the active layer 17 included in the first region functions as a light emitting layer, the active layer 17 included in the convex portion of the second region does not function as a light emitting layer. This is because the p-side electrode is not formed in the second region (convex portion 23) while the first region has the p-side electrode. That is, carriers (holes and electrons) can be supplied by energization to the active layer 17 in the first region, whereas carriers are supplied to the active layer 17 of the protrusions 23 provided in the second region by energization. Not. Thus, the convex part 23 of this invention cannot light-emit by itself. If a p-side electrode is formed on the convex portion 23 and a current is allowed to flow inside the convex portion to cause the active layer included in the convex portion to emit light, the current path becomes narrow and the driving voltage increases, which is not preferable. Further, since the area of the active layer itself in the convex portion 23 is small, it hardly participates in the light emission. Therefore, the convex portion is divided into a first region directly involved in light emission and a second region not directly involved in light emission. Is preferably formed.

  As described so far, the semiconductor light emitting device in this embodiment reduces the light emitted in the lateral direction (side surface direction of the LED) and selectively emits the light upward (observation surface side). Therefore, when the semiconductor light emitting device is disposed on a support made of an organic material, the life of the support itself can be extended. That is, by using the semiconductor light emitting device in this embodiment, it is possible to greatly reduce the deterioration of the support due to the light emitted from the side surface of the semiconductor light emitting device. Such an effect becomes more remarkable as the surface of the support (particularly, the inner wall surface forming the concave portion on which the semiconductor light emitting element is placed) is closer to the side surface of the semiconductor light emitting element.

  Further, in the semiconductor light emitting device in this example, the convex portion 23 is not formed in the region between the n-side base electrode 22 and the diffusion electrode 20, but the convex portion 23 may be formed in the region. Since the peripheral portion of the n-side pedestal electrode 22 emits light relatively strongly, the above effect can be further improved by providing the convex portion 23 between the n-side pedestal electrode 22 and the diffusion electrode 20.

  The semiconductor light emitting device having the shape having the longitudinal direction and the short direction as described above is placed on the bottom surface of the recess of the package as in the other embodiments. At this time, it is positioned and placed so that the longitudinal direction of the bottom surface of the concave portion and the longitudinal direction of the semiconductor light emitting element and the short direction of the bottom surface of the concave portion and the short direction of the semiconductor light emitting element are substantially parallel. That is, a light emitting device is provided that includes a semiconductor light emitting element having a shape having a longitudinal direction and a short direction, and a package having a bottom surface of a recess corresponding to the size and shape of the semiconductor light emitting element. As a result, even if the bottom surface of the recess has a shape having a longitudinal direction and a short side by reducing the thickness of the package, it can be a region where the semiconductor light emitting element is placed over the entire bottom surface of the recess, and the light emitting device The light extraction efficiency can be improved. In addition, when the size of the semiconductor light emitting device is the size of the entire bottom surface of the recess of the package, the side surface of the semiconductor light emitting device and the inner wall surface of the recess face each other in close proximity. By the portion, the light emitted from the end face of the semiconductor multilayer structure can be directed in the observation plane direction. Therefore, the light emitting device according to this example can significantly reduce the deterioration of the support using the organic material, which has been caused by the light emitted from the side surface of the semiconductor light emitting element.

  Based on FIG. 14, the semiconductor light emitting device in this example will be described. The semiconductor light emitting device of this example is the same as that of Example 8 described above except that the shape of the semiconductor multilayer structure in the first region, the shape of the diffusion electrode 20 associated therewith, and the formation region of the protrusions 23 are different. It is the same composition as. That is, in the semiconductor light emitting device in this example, the first region located between the n-side pedestal electrode 22 and the p-side pedestal electrode 21 has a constricted portion when viewed from the pn electrode arrangement surface side. A plurality of convex portions 23 are formed in the constricted portion. Thereby, light emission and light extraction to the observation surface side can be performed effectively.

  Specifically, in the semiconductor light emitting device in this example, the p-side pedestal electrode 21 and the n-side pedestal electrode 22 are arranged on a broken line XX. As shown in FIG. 14, the p-side diffusion electrode 20 has a longitudinal shape along the broken line XX as viewed from the electrode forming surface side. Accordingly, the shape of the semiconductor light emitting element itself is also broken line XX. It is made into the longitudinal shape along. The current flowing from the p-side pedestal electrode 21 to the n-side pedestal electrode 22 mainly flows in the direction of the broken line XX so that the path is shortest. However, in the diffusion electrode 20 between the p-side pedestal electrode 21 and the n-side pedestal electrode 22, current is supplied to a region away from the broken line XX, the p-side pedestal electrode 21, and the n-side pedestal electrode 22. As a result, light emission is weak compared to other regions. In consideration of the above circumstances, the semiconductor light emitting device in the present embodiment is provided with a constricted portion in the first region located between the n-side pedestal electrode 22 and the p-side pedestal electrode 21, and the constricted portion that should originally emit light. By removing the semiconductor laminated structure in the region corresponding to, and forming a plurality of convex portions 23 at the constricted portion, good light extraction can be realized as a result. This is because a weak light emission region corresponding to the constricted portion is intentionally removed, and a convex portion is provided in the removed region, whereby strong light emission is emitted as it is outside the side surface, and the emitted strong light emission is transmitted through the convex portion. Therefore, it is considered that the light extraction and light directivity controllability are improved.

  Based on FIG. 15, the semiconductor light emitting device in this example will be described. The semiconductor light emitting device in this example is the same as the semiconductor light emitting device in the above example, except that the shape of the semiconductor multilayer structure in the first region, the shape of the diffusion electrode 20 associated therewith, and the formation region of the convex portion 23 are different. It is the composition.

  That is, in the semiconductor light emitting device in this example, the second region where the protrusions 23 are provided is surrounded by the first region, so that the light extraction and the light directivity can be further improved. Furthermore, it is preferable that at least a part of the second region having the convex portion 23 surrounded by the first region is provided in the vicinity of the broken line XX. As described above, the current mainly flows along the direction of the broken line XX, but a part of the first region near the broken line XX is intentionally removed, and a plurality of convex portions 23 are provided in the removed region. As a result, the light extraction efficiency and the light directivity control can be effectively improved. This intentionally removes a part on the broken line XX, so that the current can be spread over a wider region of the semiconductor multilayer structure, and includes the active layer in the region removed from the broken line XX. Since relatively strong light emitted from the end surface of the semiconductor multilayer structure is turned to the observation surface side via the plurality of convex portions 23, it is considered that light extraction and light directivity controllability are improved.

  In addition, the configuration of the semiconductor light emitting device in this example is more preferably used in combination with the configuration of the semiconductor light emitting device in Example 9 described above. That is, the above-described effects can be further improved by providing the semiconductor light emitting device in this example with a constricted portion as described in Example 9 above.

  In addition, the semiconductor laminated structure in the semiconductor light emitting element in each Example mentioned above is not limited. The mixed crystal material, mixed crystal ratio, number of layers, stacking order, etc. in each semiconductor layer can be various materials and numerical values. The same applies to the p-side electrode and the n-side electrode, and the stacking order, constituent materials, film thickness, and the like can be arbitrarily set.

  The light receiving device according to the present embodiment uses a package formed in the same manner as in the first embodiment and a light receiving device as a semiconductor element, and includes a lens-shaped translucent member that collects light incident from the outside of the device onto the light receiving device. It is set as the provided photodetector.

  In the light receiving device according to the present embodiment, the first main surface and the second main surface are provided on the main surface of the package on the light incident side, whereby the first main surface and the second main surface are provided. A light receiving device with high mounting accuracy and adhesive strength to a translucent member having a corresponding mounting surface can be obtained.

  The semiconductor device according to the present invention can be used for a backlight of a liquid crystal display, a panel meter, an indicator lamp, a surface emitting switch, an optical sensor, and the like that require high-precision positioning.

FIG. 1 is a schematic perspective view (a) and a sectional view (b) showing an embodiment of a light emitting device according to the present invention. FIG. 2 is a schematic perspective view (a) and a sectional view (b) showing another embodiment of the light emitting device according to the present invention. FIG. 3 is a schematic perspective view (a) and a sectional view (b) showing another embodiment of the light emitting device according to the present invention. FIG. 4 is a schematic perspective view (a) and a sectional view (b) showing another embodiment of the light emitting device according to the present invention. FIG. 5 is a schematic perspective view showing another embodiment of the light emitting device according to the present invention. FIG. 6 is a schematic perspective view showing another embodiment of the light emitting device according to the present invention. FIG. 7 is a schematic perspective view showing another embodiment of the light emitting device according to the present invention. FIG. 8 is a schematic plan view showing a semiconductor light emitting device in one embodiment of the present invention. FIG. 9 is a schematic cross-sectional view showing a semiconductor light emitting device in one embodiment of the present invention. FIG. 10 is a schematic perspective view showing an embodiment of a light source according to the present invention. FIG. 11 is a schematic cross-sectional view showing an embodiment of a light source according to the present invention. FIG. 12 is a schematic front view showing a semiconductor light emitting device in one embodiment of the present invention. FIG. 13 is a schematic cross-sectional view showing a semiconductor light emitting device in one example of the present invention. FIG. 14 is a schematic front view showing a semiconductor light emitting device in one embodiment of the present invention. FIG. 15 is a schematic front view showing a semiconductor light emitting device in one embodiment of the present invention. FIG. 16 is a schematic cross-sectional view showing a process for forming a semiconductor device in one embodiment of the present invention. FIG. 17 is a schematic perspective view (a) and a sectional view (b) showing an embodiment of the light emitting device according to the present invention. FIG. 18 is a schematic perspective view (a) and a sectional view (b) showing an embodiment of the light emitting device according to the present invention. FIG. 19 is a schematic perspective view (a) and a sectional view (b) showing an embodiment of the light emitting device according to the present invention. FIG. 20 is a schematic perspective view (a) and a sectional view (b) showing an embodiment of the light emitting device according to the present invention. FIG. 21 is a schematic perspective view (a) and a sectional view (b) showing an embodiment of the light emitting device according to the present invention. FIG. 22 is a schematic perspective view (a) and a sectional view (b) showing an embodiment of the light emitting device according to the present invention. FIG. 23 is a schematic perspective view (a) and a sectional view (b) showing an embodiment of the light emitting device according to the present invention. FIG. 24 is a schematic perspective view (a) and a sectional view (b) showing an embodiment of the light emitting device according to the present invention. FIG. 25 is a schematic perspective view (a) and a sectional view (b) showing an embodiment of the light emitting device according to the present invention. FIG. 26 is a schematic perspective view (a) and a sectional view (b) showing an embodiment of the light emitting device according to the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Package 1a ... 1st main surface 1b ... 2nd main surface 1c ... Convex part 2 ... Lead electrode 3 ... Sealing member 4 ... Light emitting element 5 .. Wire 6... Bump 7... Fluorescent substance 8... Inner wall surface 9 of package forming recess. Package side recess 10. Bonding member 11. Conductive member 13 ... notch 14 ... sapphire substrate 15 ... buffer layer 16 ... n-type contact layer 17 ... active layer 18 ... p-type cladding layer 19 ... p-type Contact layer 20 ... diffusion electrode 21 ... p-side pedestal electrode 22 ... n-side pedestal electrode 23 ... convex portion 24 provided in the second semiconductor region ... lead frame 25 ... protruding Member 26 ... Package molding material 27 ... Convex 28 ... Concave 29 ... Package molding material injection direction 30 ... package ejection direction 31 ... light guide plate 32 ... light emitting device 33a ... first mounting surface 33b ... second mounting surface 34 ... light incident part 35 ... Light exit surface

Claims (1)

A light-emitting element , a support having a recess in which the light-emitting element is disposed, and a lead electrode connected to the light-emitting element , and of the side surfaces of the support that is perpendicular to the main surface having the recess and the A side-emitting light emitting device having a mounting surface as one of side surfaces provided in the longitudinal direction of the recess ,
The lead electrode has a connection terminal portion protruding from the side surface of the support body , and the side surface on the short side of the recess is a hanger among the side surfaces of the support body that are arranged by bending the connection terminal portion. A side light-emitting light emitting device having a recess in which a lead is disposed and an inclined surface.

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