JP5413137B2 - Light emitting device and method for manufacturing light emitting device - Google Patents

Description

  The present invention relates to a light-emitting device that can be used for a display device, a lighting fixture, a display, a backlight light source of a liquid crystal display, and the like, and a method for manufacturing the light-emitting device.

  In recent years, various electronic components have been proposed and put into practical use, and the performance required for them has been increased. Electronic components are particularly required to drive stable performance for a long time even under severe usage environments. The same applies to light emitting devices such as light emitting diodes (LEDs), and the performance required in the general lighting field, the in-vehicle lighting field, etc. is increasing day by day, especially high output (high brightness), high Reliability is required. Furthermore, a low-cost light emitting device is required while satisfying these characteristics.

  In general, a light-emitting device includes a base on which electronic components such as a semiconductor light-emitting element (hereinafter also referred to as a light-emitting element) and a protective element are mounted, and a conductive member for supplying power to the electronic components. Furthermore, the light emitting device includes a sealing member for protecting the electronic component from the external environment.

  In order to increase the output of the light emitting device, in addition to improving the output of the mounted light emitting element itself, the light extraction efficiency should be improved by the material and shape of the substrate, conductive member, sealing member, etc. Is effective.

  For example, a metal member having good conductivity is used as the material of the conductive member. By plating silver on the surface of the metal member, the light from the light emitting element can be efficiently reflected. As a material for the sealing member, a resin that easily transmits light from the light emitting element is suitable. In particular, the lifetime of the light-emitting device can be extended by using a silicone resin excellent in weather resistance and heat resistance for the sealing member.

  Here, for example, silver used as a reflective material tends to be easily deteriorated by sulfur components in the atmosphere. For this reason, various devices have been conventionally used to prevent silver deterioration. For example, a technique using an organic silver discoloration preventing agent on a silver plating layer that is a light reflecting surface in a cavity in which a light emitting element is mounted is known (see Patent Document 1). Further, in order to prevent silver discoloration in the light emitting device, a technique for applying noble metal plating on a silver plating layer that is a light reflecting surface in a cavity in which a light emitting element is mounted (see Patent Document 2), or silver plating is performed. A technique (see Patent Document 3) for covering the formed lead frame with sol-gel glass is disclosed.

  In addition, in order to increase the output of the light emitting device, the amount of heat generated by the light emitting element increases as the output of the mounted light emitting element itself is improved. Therefore, in the light emitting device, metal eutectic bonding has been used in order to efficiently dissipate the heat of the light emitting element to the package side. Accordingly, a method of improving light extraction efficiency by forming a silver film on the back surface (lower surface) of the light emitting device / metal eutectic interface and reducing light absorption by the metal eutectic is disclosed ( (See Patent Document 4). Here, if the silver film is formed even on the outer periphery of the light emitting element, peeling of the silver occurs in the process of separating the light emitting element from a wafer having a large number of light emitting elements and separating it into individual light emitting elements such as bars or chips. Sometimes. For this reason, silver may not be formed up to the outer periphery of the light emitting element. In this case, silver is deposited on the back surface (lower surface) of the light emitting element so that the area is smaller than the back surface of the light emitting element. As a result, when metal eutectic bonding is performed, the metal eutectic material is formed in the area where the silver on the back surface of the light emitting element is formed due to the wettability relationship. A gap corresponding to the thickness of the metal eutectic material is generated between the plated portion.

  For example, a wire such as a gold wire that electrically connects the electrode of the blue light emitting element and the conductive member serves as an absorption source that absorbs blue light. A technique for improving the light extraction efficiency of a light emitting device by suppressing light absorption by such a wire (see Patent Document 5) is disclosed.

JP 2006-303092 A JP 2006-303069 A JP 2007-324256 A JP 2007-266338 A JP 2009-55006 A

  It is expected that the reliability and productivity of the light-emitting device will be improved if a passivation film that protects silver or the like plated on the conductive member of the light-emitting device from sulfur components in the atmosphere is formed by a vacuum process. Is done. However, for example, in a light-emitting device that forms silver on the back surface of the light-emitting element so that the width is narrower than the width of the light-emitting element, when a passivation film is formed by a vacuum process, a conductive member is formed due to the straightness of sputtering. Among the silver-plated portions, the gap portions that are shaded by the light-emitting elements cannot be covered with the passivation film. In general, when a film is formed by sputtering, for example, a portion such as a so-called pinhole that cannot be partially formed may occur. In addition, in the cleaning process that follows the sputtering process, dust or the like is peeled off along with the passivation film formed on the surface of the light-emitting device when the film is formed by sputtering. As a result, the silver plating buried under the dust is exposed. Further, if there are minute irregularities on the substrate side on which the passivation film is to be formed, there may be a portion where the film cannot be formed. Therefore, further improvements in reliability and lifespan are demanded.

  Furthermore, in a light emitting device including a wire such as a gold wire that electrically connects the electrode of the light emitting element such as blue and the silver-plated portion of the conductive member, light irradiated from the light emitting element is absorbed by the back surface of the wire. Therefore, there is a demand for improving light extraction efficiency without absorbing light from the light emitting element in the light emitting device.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a light-emitting device with high output and high reliability. Another object of the present invention is to provide a method for manufacturing the light emitting device.

In order to solve the above problems, a light emitting device according to a first aspect of the present invention includes a base, a conductive member provided on the base, a silver-containing metal provided on at least a part of the conductive member, and placed on the light emitting element on the substrate, in the light emitting element and the silver-containing surface of the metal, and an insulating member provided so as to cover at least a portion of the silver-containing metal, covered with the insulating member And a metal layer containing a metal other than silver, which is provided so as to cover the non- conductive portion .

  According to this configuration, in the light emitting device, the insulating member is covered with the silver-containing metal or the like provided on the conductive member. Thus, even if a silver-containing metal is provided on the surface of the conductive member in order to increase the light extraction efficiency, the insulating member can protect silver from corrosive gases such as sulfide gas in the atmosphere. Therefore, it is possible to prevent the silver used for increasing the output from being discolored by the corrosive gas, and to improve the reliability and life. In the light-emitting device, a portion where the insulating member is not formed is covered with a metal layer containing a metal other than silver on the surface of the conductive member. By doing so, the part where the insulating member is not formed is protected from sulfur gas in the atmosphere and the light extraction efficiency is further improved by reflecting the light emitted from the light emitting element from the part where the insulating member is not formed. Can be increased. Here, “on the substrate” means being on the upper side of the substrate, and the light emitting element can be mounted via a conductive member and / or a silver-containing metal.

  Further, the light emitting device according to the present invention has a wire for electrically connecting a portion to be an electrode of the conductive member and an electrode terminal of the light emitting element in the light emitting device according to the first aspect of the present invention, Preferably, the insulating member is formed on the upper surface of the wire, and the metal layer is formed on the lower surface of the wire.

  According to such a configuration, in the light emitting device, the metal layer containing a metal other than silver covers the back surface of the wire on which the insulating member is not formed, so that the light directly irradiated from the light emitting element to the back surface of the wire is absorbed by the wire. As a result, the amount of absorbed light can be reduced. Therefore, the light extraction efficiency is improved and the light output can be improved.

  The light-emitting device according to the present invention is the light-emitting device according to the first aspect of the present invention, wherein the reflectance of the metal layer formed on the lower surface of the wire is 50 for light in the wavelength range of 430 nm to 490 nm. % Or more is preferable.

  According to this configuration, the light emitting device can efficiently reflect light in the wavelength range of 430 nm to 490 nm. Therefore, when a light emitting element having a peak wavelength of the emission spectrum as described above is used, the light extraction efficiency is improved and the light output can be improved.

  The light-emitting device according to the present invention is preferably the light-emitting device according to the first aspect of the present invention, further comprising a sealing member that further covers the light-emitting element and the wire.

  According to this configuration, the light emitting device can have a long life by protecting the light emitting element and the wire from dust, moisture, external force, and the like by the sealing member.

  In the light emitting device according to the first aspect of the present invention, the light emitting device according to the present invention preferably includes a reflective layer having a smaller area than the lower surface of the light emitting element on the lower surface side of the light emitting element.

  According to such a configuration, the light emitting device includes the reflective layer having a small contact area on the lower surface side of the light emitting element, and therefore, the light traveling from the light emitting element in all directions toward the lower reflective layer is the reflective layer. The light is reflected, proceeds to the upper surface side of the light emitting element, and is extracted outside. However, of the light traveling downward from the light emitting element, the light traveling to the outer peripheral side of the reflective layer is not reflected by the reflective layer but is reflected by the substrate on which the light emitting element is mounted and extracted outside the light emitting element. Become. Further, even if the insulating member cannot be formed on the side surface of the reflective layer or the surrounding area below the reflective layer, the portion where the insulating member is not formed is covered with a metal layer containing a metal. Therefore, the metal layer can protect the side surface of the reflective layer and the surrounding area below the reflective layer, and can efficiently reflect the light traveling below the light emitting element. This also suppresses deterioration of the silver provided in the vicinity of the light emitting element, in particular, sulfidation, thereby reducing the adverse effect on the light output of the light emitting device and obtaining a high output light emitting device.

  In order to solve the above problem, a light emitting device according to a second aspect of the present invention includes a base, a conductive member provided on the base, a light emitting element placed on the base, and the conductive A wire for electrically connecting a portion to be an electrode of the member and an electrode terminal of the light emitting element, an insulating member provided so as to cover the light emitting element and the wire from above, and the light emitting element and the wire And a metal layer containing a metal other than silver provided so as to cover a portion where the insulating member is not formed on the surface.

  According to such a configuration, in the light emitting device, the metal layer containing a metal other than silver covers the lower surface of the wire, thereby reducing the amount of light absorbed by the wire that is directly irradiated from the light emitting element to the back surface of the wire. be able to. Therefore, the light extraction efficiency is improved and the light output can be improved.

  The light-emitting device according to the present invention is the light-emitting device according to the first and second aspects of the present invention, wherein the metal layer has ruthenium, rhodium, palladium, osmium, iridium, platinum, chromium, nickel, titanium. The metal is preferably a metal selected from the group consisting of zinc or an alloy containing at least the metal.

  According to such a configuration, in the light emitting device, the metal layer containing a metal other than silver covering the portion where the insulating member is not formed contains a noble metal silver metal such as a platinum group having a high light reflectance. Light from the light emitting element can be reflected efficiently. Therefore, the light extraction efficiency is improved and the light output can be improved.

In order to solve the above problems, a method for manufacturing a light-emitting device according to the present invention includes a die bonding step of bonding a light-emitting element to a substrate provided with a conductive member at least partially coated with a silver-containing metal, An insulating member forming step of forming an insulating member so as to cover the light emitting element and the silver-containing metal on a part of the surface of the light emitting element and the silver-containing metal, and a conductor portion not covered with the insulating member And a metal layer forming step of forming a metal layer containing a metal other than silver by electroplating.

  According to such a procedure, the light emitting device manufacturing method forms the insulating member in the insulating member forming step. Therefore, even if a silver-containing metal is used on the surface of the conductive member in order to increase the light extraction efficiency, Silver can be protected from sulfide gas or the like in the atmosphere by the filmed insulating member. And since the manufacturing method of the light emitting device coats with a film of a metal layer containing a metal other than silver by electrolytic plating in the metal layer forming step even if a pinhole or the like occurs in the film formation of the insulating member, The silver-containing metal on which the insulating member is not formed can be protected from sulfur gas in the atmosphere. Therefore, the reliability and productivity of the light emitting device can be improved. Furthermore, this metal layer can improve the light extraction efficiency by reflecting light emitted from the light emitting element from a portion having a low reflectivity where an insulating member is not formed. Here, the metal used for the metal layer is a metal that can be electroplated, and preferably contains a noble metal-based silver stable metal such as a platinum group having a high light reflectance.

  In the method for manufacturing a light emitting device according to the present invention, after the die bonding step, the portion serving as the electrode of the conductive member and the electrode terminal of the light emitting element are electrically connected by a wire through the silver-containing metal. A wire bonding step, wherein in the insulating member forming step, an insulating member is formed so as to cover the light emitting element, the silver-containing metal and the wire from above, and in the metal layer forming step, the light emitting element, It is preferable to form a metal layer containing a metal other than silver by electrolytic plating so as to cover the silver-containing metal and the portion where the insulating member is not formed on the surface of the wire.

  According to such a procedure, the method for manufacturing the light emitting device performs the metal layer forming step subsequent to the wire bonding step and the insulating member forming step. Therefore, the metal layer containing metal is also formed on the back surface of the wire on which the insulating member is not formed. Can be formed. Thereby, the absorption amount by which the light directly irradiated from the light emitting element to the back surface of the wire is absorbed by the wire can be reduced. Therefore, the light emitting device can improve the light extraction efficiency and improve the light output.

According to the light emitting device of the present invention, the conductive member or the like can be protected by the insulating member or the metal layer of metal other than silver, and light from the light emitting element can be efficiently extracted to the outside by the metal layer of metal other than silver. Therefore, high output and high reliability can be realized.
According to the method for manufacturing a light emitting device of the present invention, a conductive member or the like is protected by an insulating member, and a metal metal layer is formed on the insulating member by electrolytic plating. Can be easily manufactured.

It is a perspective view which shows an example of the light-emitting device which concerns on embodiment of this invention. FIG. 2 is a plan view of the light emitting device shown in FIG. 1 as seen partially from the light emitting surface side. FIG. 3 is an XX cross-sectional arrow view of the light emitting device shown in FIG. 2. It is sectional drawing which shows the manufacturing process of the light-emitting device which concerns on embodiment of this invention. It is sectional drawing which shows the manufacturing process of the light-emitting device which concerns on embodiment of this invention. It is sectional drawing which shows the manufacturing process of the light-emitting device which concerns on embodiment of this invention. It is sectional drawing which shows the manufacturing process of the light-emitting device which concerns on embodiment of this invention. It is sectional drawing which shows the manufacturing process of the light-emitting device which concerns on embodiment of this invention. It is sectional drawing which shows the modification of the light-emitting device which concerns on embodiment of this invention. It is the top view which permeate | transmitted partially the other modification of the light-emitting device which concerns on embodiment of this invention from the light emission surface side. It is a YY cross-sectional arrow view of the light-emitting device shown in FIG.

  A mode for carrying out the present invention will be described below with reference to the drawings. However, the embodiment described below exemplifies a light emitting device and a manufacturing method thereof for embodying the technical idea of the present invention, and the present invention limits the light emitting device and the manufacturing method thereof to the following. is not. Moreover, the same name and code | symbol have shown the member same or the same quality, and abbreviate | omits detailed description suitably.

  In the following, 1. 1. Outline of configuration of light emitting device 2. Manufacturing method of light emitting device Each of the members constituting the light-emitting device will be described in order in each chapter.

[1. Outline of configuration of light emitting device]
An outline of a configuration of a light emitting device according to an embodiment of the present invention will be described with reference to FIGS. In the light emitting device 100 shown in FIG. 1, the base 101 is configured by firing a plurality of laminated ceramic green sheets, for example. The base 101 has a recess 109. Recess 109 has an open top surface and a side surface and a bottom surface. After the light emitting element 104 (see FIG. 2) is placed in the recess 109, the recess 109 is sealed with a sealing member 108 made of resin or the like.

  FIG. 2 is a plan view of the light emitting device 100 as seen through the sealing member 108 from the light emitting surface side. Conductive members 102A and 102B as electrodes are disposed on the bottom surface of the recess 109 so as to be exposed. As shown in FIG. 2, the conductive member 102A exposed on the bottom surface of the recess 109 is a cathode (-electrode), and the conductive member 102B exposed on the bottom surface of the recess 109 is an anode (+ electrode). On the cathode-side conductive member 102A, a semiconductor light emitting element (hereinafter referred to as a light emitting element) 104 and a protection element 105 are provided as electronic components. The positive and negative electrodes (electrode terminals) of the light-emitting element 104 are electrically connected to the conductive members 102A and 102B by conductive wires 106, respectively.

  The protection element 105 is composed of, for example, a Zener diode. The protective element 105 has a positive electrode on the bottom side thereof fixed to the conductive member 102 </ b> A by a bonding member such as a metal paste, and is electrically connected, and a negative electrode is electrically connected to the conductive member 102 </ b> B by a wire 106. A cathode mark 107 is provided on the upper surface of the base 101 to indicate which of the conductive members 102A and 102B is on the cathode side. Note that an anode mark may be provided instead of the cathode mark to indicate the polarity of the light emitting device 100.

As shown in FIG. 3, the conductive members 102 </ b> A and 102 </ b> B are provided so as to be exposed also on the lower surface (back surface) of the base 101 in order to function as terminals electrically connected to the outside. The conductive member 102 </ b> A disposed on the back surface of the base body 101 is provided so as to be electrically continuous with the conductive member 102 </ b> A disposed on the bottom surface of the recess 109 inside the base body 101. Similarly, the conductive member 102 </ b> B disposed on the back surface of the base body 101 is provided so as to be electrically continuous inside the base body 101 with the conductive member 102 </ b> B disposed on the bottom surface of the recess 109. And the silver containing metal 103 as a reflecting material is provided by the plating etc. on the surface of the electrically-conductive members 102A and 102B exposed on the bottom surface of the recess 109, respectively. Further, the light-emitting element 104 is provided on the surface of the silver-containing metal 103 provided on the bottom surface of the recess 109 via the adhesive layer 123, and the other surface of the silver-containing metal 103 is covered with the insulating member 110. ing. In addition, a metal layer 112 is formed at a portion where the insulating member 110 is not formed and the silver-containing metal 103 is exposed. In particular the lower region of the light emitting element 104, a silver-containing metal 103 is coated with a metal layer 1 12, including the portion exposed.

  For example, as shown in FIG. 4, the light emitting element 104 includes a substrate 104a, a laminated semiconductor structure 104b such as a light emitting layer sequentially laminated on the substrate 104a, and an electrode terminal 104c formed on the laminated semiconductor structure 104b. Have. Note that the positive and negative electrode terminals of the light-emitting element 104 are provided on a surface where a different semiconductor layer is exposed.

  Further, for example, a patterned Ag / Pt / AuSn film can be formed on the lower surface (back surface) of the light emitting element 104. In the example shown in FIG. 3, between the light emitting element 104 and the base 101, in order from the lower surface side of the light emitting element 104, for example, a reflective layer 121 made of Ag, a barrier layer 122 made of Pt, and a metal substrate as a die bond member. An adhesive layer 123 made of AuSn which is a crystal is disposed. The areas of the reflective layer 121, the barrier layer 122, and the adhesive layer 123 arranged on the lower surface side of the light emitting element 104 are smaller than the area of the back surface of the light emitting element 104 (see FIG. 4).

  For example, after the light emitting element 104 has undergone a die bonding process that is placed on the flux applied to the bottom surface of the recess 109, a subsequent reflow process, and a cleaning process, each wire 106 is arranged on the bottom surface of the recess 109. Are connected to the silver-containing metal 103 on the surfaces of the conductive members 102A and 102B.

  As described above, the light emitting device 100 includes the insulating member 110 that mainly protects the silver-containing metal 103 on the surfaces of the conductive members 102A and 102B in the recess 109 of the base 101. In addition to the silver-containing metal 103, the insulating member 110 is provided so as to cover the surface of the light emitting element 104, the wire 106, and the base 101 (the bottom surface and side surfaces of the recess 109) from above in the recess 109. Further, the insulating member 110 covers the upper surface of the base 101 in addition to the recess 109.

  Further, as described above, the light emitting device 100 includes the metal layer 112 so as to cover the exposed surface of the silver-containing metal 103 disposed in the recess 109 of the base 101. In FIG. 3, the metal layer 112 is provided so as to cover a portion where the insulating member 110 is not formed on the surface of the conductor portion such as the light emitting element 104, the wire 106, and the silver-containing metal 103. The metal layer 112 includes, for example, a silver-containing metal 103 positioned below the light emitting element 104, a reflection layer 121 disposed below the light emitting element 104, a side surface of the barrier layer 122, the adhesive layer 123, and a lower surface of the wire 106 ( The back surface). The metal layer 112 is a reflective film that includes a highly reflective metal other than silver and reflects light from the light emitting element 104. Details of the metal layer 112 will be described later.

As described above, in the light emitting device 100, the silver-containing metal 103 provided on the conductive members 102 </ b> A and 102 </ b> B is covered with the insulating member 110, and the conductor portion where the insulating member 110 is not formed includes a metal containing a metal other than silver. Covered with a layer 112. Therefore, silver can be protected from corrosive gases such as sulfide gas in the atmosphere. Accordingly, silver degradation can be suppressed even in an environment where the light emitting device 100 is exposed to the atmosphere. In addition, the light emitting device 100 includes a highly reflective metal layer 112 that covers a conductor portion on which the insulating member 110 is not formed. Therefore, in the light-emitting device 100, when the light-emitting element 104 emits light, the light is reflected by the metal layer 112, and light can be efficiently extracted outside. In the light emitting device 100, since the insulating member 110 is formed on the upper surface of the wire 106, the adhesion between the wire 106 and the sealing member 108 (see FIG. 8) can be improved.
Furthermore, since the back surface of the wire 106 is covered with the highly reflective metal layer 112 in the light emitting device 100, when the light emitting element 104 disposed below the wire 106 is caused to emit light, the back surface side of the wire 106. The amount of light absorption can be reduced. At this time, the highly reflective metal layer 112 covering the back surface of the wire 106 reflects light emitted from the light-emitting element 104, so that light can be efficiently extracted to the outside. Through the above operation, a light-emitting device with high output, high reliability, and long life can be realized.

[2. Manufacturing method of light emitting device]
Next, a method for manufacturing a light emitting device according to an embodiment of the present invention will be described. The light emitting device 100 shown in FIGS. 1 to 3 can be obtained through the manufacturing steps shown in FIGS. 4 to 8, for example. That is, the light emitting device manufacturing method mainly includes a die bonding step (see FIG. 4), a wire bonding step (see FIG. 5), an insulating member forming step (see FIG. 6), and a metal layer forming step (see FIG. 7). ). Furthermore, when forming the sealing member 8, a sealing member formation process (refer FIG. 8) is performed.

  The die bonding step (see FIG. 4) can be performed by various methods depending on the type of the die bonding member for bonding the light emitting element 104 to the substrate 101, the bonding method, and the like. Here, the die bonding process is based on the premise that the base 101 and the light emitting element 104 have already been manufactured. However, for example, a step of providing the conductive members 102A and 102B on the base 101 or a step of providing the silver-containing metal 103 on the conductive members 102A and 102B may be performed before the die bonding step. Among these, the step of providing the conductive members 102A and 102B on the base 101 can be performed by various methods depending on the material of the base 101, the materials of the conductive members 102A and 102B, and the method used in the die bonding step. Closely related.

  Here, the manufacturing method of the light emitting device 100 is formally divided into a first process to a sixth process, and a silver-containing metal forming process (first process), a die bonding process (second process), and a wire bonding process (first process). 3 steps), an insulating member forming step (fourth step), a metal layer forming step (fifth step), and a sealing member forming step (sixth step) will be sequentially described.

  For convenience, each manufacturing process will be described using one light-emitting device 100 with reference to FIGS. 4 to 8 as appropriate. In these manufacturing processes, a plurality of light-emitting device substrates are aggregated. Yes. Then, after the aggregate of the substrates is divided in the final process, the outer surface of the substrate 101 of each light emitting device 100 is exposed.

<2-1. First step (silver-containing metal forming step)>
The first step is a step until the silver-containing metal 103 is provided on the conductive members 102 </ b> A and 102 </ b> B of the light emitting device 100. Here, 2-1-A. A conductive member forming step, and 2-1-B. A silver plating process is performed.

<< 2-1-A. Conductive member formation process >>
As shown in FIG. 4, in this embodiment, the base 101 of the light emitting device 100 has a recess 109. Conductive members 102A and 102B are formed on the bottom surface of the recess 109 of the base 101 so as to be exposed.

  The conductive members 102A and 102B can be provided on the inner side wall of the recess 109 to provide a function as a reflecting member, in addition to being used as an electrode for energizing. In addition, the conductive members 102A and 102B can be exposed from the back surface of the base 101 to provide a function as a heat radiating member. The conductive members 102 </ b> A and 102 </ b> B exposed from the back surface of the substrate 101 can also have a function as an electrode. In addition, the conductive member used as the electrode and the conductive member used as the heat dissipation member can be electrically blocked. The conductive member can also be provided as a cathode mark 107 indicating the polarity of the light emitting device 100 as shown in FIG.

  The method of forming such conductive members 102A and 102B can be changed as appropriate according to the material of the base 101 and the like. For example, in the case of using the substrate 101 made of ceramic, the conductive paste is applied by baking a conductive paste containing fine particles of a refractory metal such as tungsten or molybdenum at a stage of an unfired ceramic green sheet. The members 102A and 102B can be obtained. Alternatively, the conductive members 102A and 102B can be formed on a pre-fired ceramic plate.

  For example, when a glass epoxy resin substrate is used as the substrate 101, the conductive members 102A and 102B can be formed as follows. In this case, first, a copper plate is attached to a prepreg obtained by semi-curing an epoxy resin containing glass cloth or an epoxy resin and thermally cured. Thereafter, a metal member such as copper is patterned into a predetermined shape using a photolithography method. Thereby, the conductive members 102 </ b> A and 102 </ b> B can be formed in the base 101.

<< 2-1-B. Silver plating process >>
Subsequently, the silver-containing metal 103 is provided on the conductive members 102A and 102B formed as described above. Note that the silver-containing metal 103 is not provided on the conductive member embedded in the base 101.

  As a method for providing the silver-containing metal 103, a plating method, a sputtering method, a vapor deposition method, or the like can be used. When the plating method is used, any method of electrolytic plating and electroless plating can be used. For example, in the case where the silver-containing metal 103 is provided only on the conductive members 102A and 102B, it is easiest to use the electrolytic plating method after electrically connecting the corresponding parts. In the case where an electroless plating method, a sputtering method, or a vapor deposition method is used, it can be provided only on the conductive members 102A and 102B by a photolithography method.

  The silver-containing metal 103 may be provided directly on the base conductive members 102A and 102B, or may be indirectly provided on the conductive members 102A and 102B through a metal not containing silver. Further, after the silver-containing metal 103 is provided on the conductive members 102A and 102B that are not particularly patterned, the conductive members 102A and 102B and the silver-containing metal 103 may be patterned into a predetermined shape. Note that the surfaces of the conductive members 102 </ b> A and 102 </ b> B may be at least partially covered with the silver-containing metal 103.

<2-2. Second process (die bonding process)>
The second step is a step of bonding the light emitting element 104 to the conductive members 102A and 102B of the light emitting device 100 via a die bonding member such as a resin composition. Here, 2-2A. Resin composition forming step, 2-2B. And heating step.

<< 2-2-A. Resin composition forming process >>
The resin composition may be formed so as to be interposed between the conductive members 102A and 102B and the light emitting element 104. Therefore, the site | part which forms a resin composition may be any of following (A1)-(A3).
(A1) Region on which the light emitting element 104 is placed on the conductive members 102A and 102B (A2) The back surface of the light emitting element 104 (A3) Both A1 and A2

  The component of the resin composition includes, for example, rosin (pine resin) or a thermosetting resin. Furthermore, you may make the resin composition contain activators, such as a solvent for viscosity adjustment, various additives, and an organic acid, as needed. Furthermore, a powdered metal may be contained. The resin composition can be in the form of a liquid, paste, or solid (sheet, block, or powder). Depending on the composition of the resin composition or the shape of the substrate 101, the resin composition can be used. The shape of the composition can be appropriately selected.

  Next, in the case where the part where the resin composition is formed is the above-described (A1) region where the light emitting element 104 is placed on the conductive members 102A and 102B, the resin composition forming method and the resin composition ( A method of joining via flux or solder will be described.

  First, as shown in FIG. 4, a liquid or paste-like resin composition 111 is formed on the silver-containing metal 103 provided on the conductive members 102A and 102B. As described above, a method of forming the liquid or paste-like resin composition 111 on the conductive members 102A and 102B is appropriately selected from methods such as a potting method, a printing method, and a transfer method according to the viscosity of the resin composition 111 and the like. You can choose. Subsequently, the light emitting element 104 is placed on the place where the resin composition 111 is formed. In the case where a solid resin composition is provided, a method such as installation on an insulating member can be used in the same manner as the light-emitting element 104 is mounted. The light-emitting element 104 may be fixed by melting a liquid, paste-like, or solid resin composition once by heating or the like. Moreover, a resin composition may be used independently or may be used in combination.

  The amount of the resin composition may be adjusted to be equal to or larger than the bonding area of the mounted light emitting element 104 after the light emitting element 104 is installed to form the resin composition. preferable. Further, when the plurality of light emitting elements 104 are placed on the liquid or paste resin composition 111, the light emitting elements 104 move due to the surface tension of the liquid or paste resin composition 111 and the predetermined position. May be off. Therefore, in order to prevent such a situation, it is desirable to place each light emitting element 104 on the resin composition 111 that is individually independent.

  The amount of the resin composition 111 illustrated in FIG. 4 was adjusted so as to be an area larger than the bonding area of the light emitting element 104 to be mounted, so that the resin composition 111 was formed. In this case, after the light-emitting element 104 is installed, the resin composition 111 is in a state of being wider than the bonding area of the adhesive layer 123 provided below the light-emitting element 104.

  In addition, the thickness of the resin composition is preferably adjusted in consideration that the suitable thickness varies depending on the type of the resin composition. As for the thickness of the resin composition, when the light emitting element 104 is placed, the resin composition is crushed and spreads sideways as it is, or the resin composition follows the unevenness of the base 101 and spreads. It is preferable to adjust in consideration of the above.

Further, depending on the material of the light-emitting element 104, the bonding method, and the like, it is preferable to include a conductive member in the resin composition. For example, the following specific examples B1 and B2 can be given.
(B1) Using this light-emitting element 104 manufactured by using a conductive silicon (Si) substrate as the light-emitting element substrate 104a and laminating gallium nitride-based semiconductor layers to form a laminated semiconductor structure 104b, this nitriding is performed. (B2) An insulating sapphire substrate is used as the substrate 104a of the light emitting element, and a gallium nitride based semiconductor layer is laminated to form a laminated semiconductor structure. In the case where the sapphire surface of the gallium nitride based semiconductor light-emitting device is used as a bonding surface using the light-emitting device 104 manufactured by configuring the light-emitting device 104b

  In the case of the specific example (B1), the conductive members 102A and 102B provided on the base body 101 and the light emitting element 104 need to be conducted at the joint portion. Therefore, in such a case, it is preferable to mix a conductive member such as a metal having a relatively low melting point in the resin composition.

<< 2-2-B. Heating process >>
In the heating step, heating is performed at a temperature higher than the temperature at which at least a part of the resin composition formed as described above volatilizes. The heating temperature varies depending on the substance contained in the resin composition. For example, the following (C1) to (C3) can be mentioned.
(C1) When the resin composition contains a thermosetting resin, it is preferably heated to a temperature higher than the temperature at which the resin is cured.
(C2) When the resin composition contains rosin and a metal film having a low melting point is provided on the light-emitting element 104 or the silver-containing metal 103, the temperature exceeds the temperature at which the metal having the low melting point melts. It is preferable to heat.
(C3) Even when the resin composition contains both rosin and a metal having a low melting point, it is preferably heated to a temperature equal to or higher than the temperature at which the metal having a low melting point is melted.

  The case of (C2) will be described in more detail. Here, it is assumed that a metal film is provided on the back surface of the light emitting element 104. For example, when a metal film is formed on the silicon surface of the gallium nitride based semiconductor light emitting device using the silicon substrate of the specific example (B1), or a gallium nitride based semiconductor using the sapphire substrate of the specific example (B2). In the case where a metal film is formed on the sapphire surface of the light emitting element, the metal film and the silver-containing metal 103 are formed by the action of the rosin component in the resin composition by heating and the phenomenon that the metals try to diffuse each other. And a metal bond can be formed. Thereby, the light emitting element 104 can be fixed more firmly. In the specific example (B1), the conductive members 102A and 102B and the light emitting element 104 can be electrically connected.

  In the heating step, a washing step can be further performed after the heating. In particular, when it is desired to remove most or all of the resin residue of the resin composition containing rosin, it is preferable to perform a washing step.

<2-3. Third Step (Wire Bonding Step)>
The third step is a step of electrically connecting the conductive members 102 </ b> A and 102 </ b> B as electrodes covered with the silver-containing metal 103 in the second step and the electrode terminals on the light emitting element 104 with a conductive wire 106. FIG. 5 shows a state in which the third step is completed. Note that the adhesive layer 123 illustrated in FIG. 5 is obtained by deforming the adhesive layer 123 illustrated in FIG.

<2-4. Fourth step (insulating member forming step)>
In the fourth step, following the third step, the insulating member is an insulating protective film so as to cover the conductive members 102A and 102B covered with the silver-containing metal 103, the light emitting element 104 and the wire 106 from above. The member 110 is provided, and FIG. 6 shows a state where the fourth step is completed.

  As shown in FIG. 6, by covering the silver-containing metal 103 with the insulating member 110, it is possible to suppress silver alteration due to sulfidation or the like. Therefore, the silver-containing metal 103 exposed on the top and side surfaces of the substrate 101 and the silver-containing metal exposed on the inner surface (bottom surface and side surfaces) of the recess 109 provided in the substrate 101 in the stage of performing the fourth step. It is preferable to form the insulating member 110 so as to cover a position where a component (such as a sulfur component-containing gas) that alters silver easily reaches from the outside in the entire exposed region including 103. In addition, it is preferable that the insulating member 110 is formed so as to cover a region having an area of at least 40% or more of the total area of the entire exposed region of the silver-containing metal 103 exposed from the base 101 at this stage. Further, the insulating member 110 is formed so as to cover almost the entire area excluding the silver-containing metal 103 exposed on the back surface of the base 101 out of the entire exposed region of the silver-containing metal 103 exposed from the base 101 at this stage. It is more preferable.

  Further, in the stage of performing the fourth step, the area of 90% or more of the entire area is limited to the exposed region of the silver-containing metal 103 exposed only on the inner surface (bottom surface, side surface) of the recess 109. It is preferable to form the insulating member 110 so as to cover this region. Furthermore, at this stage, it is preferable to provide the insulating member 110 so as to cover almost 100% of the exposed region of the silver-containing metal 103 on the inner surface (bottom surface, side surface) of the recess 109.

  Furthermore, it is preferable to provide a state where the insulating member 110 covers the silver-containing metal 103 so that there is no region where the silver-containing metal 103 is exposed after all steps such as division are completed. Note that the silver-containing metal 103 (silver-containing metal 103 embedded in the mounting region of the light emitting element 104, the bonding region of the wire 106, or the like) embedded in the substrate 101 or the substrate 101 in the step of performing the fourth step. The insulating member 110 is not provided up to the silver-containing metal 103 exposed on the lower surface (back surface).

  As shown in FIG. 6, the insulating member 110 is formed so as to cover the entire area of the silver-containing metal 103 provided on the surface of the conductive members 102 </ b> A and 102 </ b> B exposed from the base 101 on the bottom surface of the recess 109. In this way, by providing the insulating member 110 so as to cover almost the entire exposed region of the silver-containing metal 103 provided on the bottom surface of the recess 109, the deterioration of the silver-containing metal 103 and the accompanying light absorption loss are suppressed. be able to.

  This insulating member 110 may be provided other than on the silver-containing metal 103. For example, as illustrated in FIG. 6, the insulating member 110 includes a base exposed portion 101 </ b> A and a concave portion 109 where the base 101 is exposed between the positive and negative conductive members 102 </ b> A and 102 </ b> B on the bottom surface of the concave portion 109 provided in the base 101. The side wall 101B and the upper surface 101C of the base 101 can be provided.

  As will be described later, it is preferable to use an inorganic material for the material of the insulating member 110. As a method of forming the insulating member 110, a PVD (Physical Vapor Deposition) method such as a sputtering method, a vapor deposition method, or an ion plating method, A film forming method such as a CVD (Chemical Vapor Deposition) method, thermal spraying, or coating treatment can be used. For example, the insulating member 110 can be formed by a vacuum process.

  As shown in FIG. 6, alteration such as sulfidation can be suppressed by covering the silver-containing metal 103 with the insulating member 110. However, if the concave portion 109 is temporarily sealed after the completion of the fourth step, there is the following inconvenience. That is, as shown in FIG. 6, when a part of the outer periphery of the back surface of the light emitting element 104 is not in contact with the silver-containing metal 103 (there is a portion where the reflective layer 121 or the like is not formed on the back surface of the light emitting element 104) In some cases, such as when there is a gap between the silver-containing metal 103 and the silver-containing metal 103, the insulating member 110 applied in the fourth step may not be able to cover all of the silver-containing metal 103. In addition, as shown in FIG. 6, pin holes 131 and the like may occur in the insulating member 110 due to various causes. In this case, a corrosive gas enters from the pinhole and corrodes the silver-containing metal 103. However, since the manufacturing method of the light emitting device according to the present embodiment includes the next fifth step after the fourth step is completed and before the recess 109 is sealed, such a situation can be prevented.

<2-5. Fifth step (metal layer forming step)>
In the fifth step, the metal layer 112 containing a highly reflective metal other than silver is electroplated on the portion where the insulating member 110 formed in the fourth step is not formed and the portion where the conductive portion such as silver is exposed. FIG. 7 shows a state in which the fifth step is completed. As a material of the metal layer 112, a metal that can be plated can be used.

  For example, when rhodium is used as the material of the metal layer 112, an acidic solution containing, for example, 3% rhodium is prepared as a plating solution. Then, a rectangular substrate aggregate in which several hundreds of light emitting devices 100 that have been wire-bonded are arranged in a matrix is immersed in the plating solution. Then, a positive electrode for electroplating (not shown) in which the conductive members 102A and 102B of the light emitting device 100 are electrically connected, and a platinum negative electrode (not shown) that is preliminarily immersed in the plating solution and disposed opposite to each other. In the middle, electrolytic plating is performed by applying a voltage from a power supply device (not shown).

  At this time, the plus side electrode is electrically connected to the conductive members 102A and 102B of the light emitting device 100 of the substrate assembly, and a voltage is applied between the minus side electrode of platinum. Thereby, the electrolytic plating can be simultaneously performed on the individual substrates 101 of the substrate assembly.

  In the fifth step, the metal layer 112 is formed by electroplating, so that, for example, the high-reflection other than silver is selectively applied to the gap portion on the back surface side of the light emitting element 104 and the conductor portion such as the pinhole 131. A metal layer 112 containing an index metal can be formed. That is, in the case of the electrolytic plating method, if the insulating member 110 is formed on the silver-containing metal 103, no potential is generated in that portion, and thus the metal layer 112 is not formed on the surface of the insulating member 110. Thereby, the surface of the part (conductor part) where the silver-containing metal 103 is exposed without forming the insulating member 110 can be easily covered with the metal layer 112.

<2-6. Sixth step (sealing member forming step)>
In the sixth step, the sealing member 108 that covers the light emitting element 104 is formed and cured. FIG. 8 is a view showing that the sealing member 108 is filled in the recess 109 and the light emitting element 104 is covered. When the recess 109 is formed in the base 101 as described above, the sealing member 108 can be easily formed by injecting molten resin into the recess 109. The formed sealing member 108 can be cured by heating, light irradiation, or the like. Conditions for curing the sealing member 108 can be appropriately selected depending on the material of the sealing member 108 to be used. Note that the sealing member 108 can be formed of a single member, or can be formed as a plurality of layers of two or more layers.

  In the case where the sealing member 108 is cured by heating, the temperature, temperature, time, atmosphere, and the like of temperature increase or decrease can be appropriately selected. Further, when the sealing member 108 is cured by light irradiation, the light irradiation time, the wavelength of the irradiation light, and the like can be appropriately selected according to the material of the sealing member 108 to be used. Further, the sealing member 108 may be cured by using both heating and light irradiation.

[3. Each member constituting the light emitting device]
Here, 3-1. Substrate, 3-2. Conductive member, 3-3. Silver-containing metal, 3-4. Insulating member, 3-5. Metal layer, 3-6. Die bond member (resin composition and metal bonding member), 3-7. Sealing member, 3-8. Wire, 3-9. Wavelength conversion member, 3-10. Light emitting element, 3-11. Each member constituting the light emitting device 100 will be described in order, divided into sections of metal film.

<3-1. Base>
In the present embodiment, the base 101 is provided with conductive members 102A and 102B for protecting electronic components such as the light emitting element 104 and the protective element 105 and supplying electric current from the outside to these electronic components. . As a material of the base 101, an insulating member is preferable, and a member that hardly transmits light from the light emitting element 104, external light, or the like is preferable. Moreover, what has a certain amount of strength is preferable, and more specifically, ceramics (Al ₂ O ₃ , AlN, etc.), phenol resin, epoxy resin, polyimide resin, BT resin (bismaleimide triazine resin), PPA (polyphthalamide) ) And the like. When the material of the substrate 101 is a resin, glass fibers and inorganic fillers (SiO ₂ , TiO ₂ , Al ₂ O _3, etc.) are mixed to improve mechanical strength, reduce thermal expansion, and reflectivity. Improvements can also be achieved.

<3-2. Conductive member>
The conductive members 102A and 102B are for electrically connecting the light emitting element 104 to the outside. A preferable material for the conductive members 102A and 102B can be appropriately selected according to the material of the base 101, the manufacturing method of the base 101, and the like.

  For example, when ceramic is used as the material of the substrate 101, the material of the conductive members 102A and 102B is preferably a member having a high melting point that can withstand the firing temperature of the ceramic sheet, and has a high melting point such as tungsten or molybdenum. It is preferable to use a metal.

  For example, when glass epoxy resin or the like is used as the material of the substrate 101, the material of the conductive members 102A and 102B is preferably a material that can be easily processed. Specifically, copper, aluminum, gold, silver, tungsten, Examples thereof include metals such as iron and nickel, iron-nickel alloys, phosphor bronze, iron-containing copper, and molybdenum.

  For example, when the base 101 is made of an injection-molded epoxy resin, the conductive members 102A and 102B are preferably members having a relatively large mechanical strength. In this case, the material of the conductive members 102A and 102B is preferably a member that is easy to be punched, etched, bent, and has a relatively large mechanical strength. Specific examples include metals such as copper, aluminum, gold, silver, tungsten, iron, and nickel, or iron-nickel alloys, phosphor bronze, iron-containing copper, and molybdenum.

<3-3. Silver-containing metal>
The silver-containing metal 103 is provided on the surfaces of the conductive members 102A and 102B exposed from the base 101. As a method for forming the silver-containing metal 103, a plating method, a sputtering method, a vapor deposition method, or the like can be used. The material of the silver-containing metal 103 may be only silver, or an alloy of silver and a metal having a high light reflectance such as copper, gold, aluminum, rhodium, or a multilayer of silver and a metal having a high light reflectance. A film or the like may be used. Preferably, it is composed of silver alone. In addition, the film thickness of the silver-containing metal 103 is preferably a film thickness that can efficiently reflect light from the light emitting element 104, and specifically, about 1 nm to 50 μm is preferable. In addition, when making the silver containing metal 103 into a multilayer film, it is preferable that the thickness of the whole multilayer film shall be in this range.

<3-4. Insulating material>
The insulating member 110 is mainly provided on the silver-containing metal 103. It is preferable to provide the insulating member 110 so as to cover almost the entire region of the silver-containing metal 103 exposed from the base 101 in a state before the insulating member 110 is manufactured. As a material of the insulating member 110, a light-transmitting material is preferable, and it is preferable to mainly use an inorganic compound. _{Specifically, SiO 2, Al 2 O 3} , TiO 2, ZrO 2, ZnO 2, Nb 2 O 5, MgO, SrO, In 2 O 3, TaO 2, HfO, SeO, oxidation, such as Y 2 _{O 3} And nitrides such as SiN, AlN, and AlON, and fluorides such as MgF ₂ . These may be used alone or in combination. Alternatively, it may be laminated.

  As for the film thickness of the insulating member 110, it is preferable to reduce the film thickness so that light loss does not occur due to multiple reflection at the interface of the sealing member 108 / insulating member 110 and the interface of the insulating member 110 / silver-containing metal 103. Further, a thickness that does not allow gas such as sulfur to pass through is also necessary. Although the preferable range of the film thickness differs somewhat depending on the type of material used for the insulating member 110, the film thickness of the insulating member 110 is preferably about 1 nm to 10 μm. When the insulating member 110 is a multilayer, it is preferable that the film thickness of the entire layer be within this range. In addition, the insulating member 110 is preferably formed as a dense film so that a gas such as sulfur is difficult to pass.

<3-5. Metal layer>
The metal layer 112 is a reflective film containing a highly reflective metal other than silver. The metal layer 112 is provided on the conductor including the silver-containing metal 103 in the recess 109 of the base 101. It is preferable to provide the metal layer 112 so as to cover almost the entire region of the silver-containing metal 103 exposed in the recess 109 before the metal layer 112 is formed. The material of the metal layer 112 is preferably a material having a high light reflectance. Specific examples include ruthenium, rhodium, palladium, osmium, iridium, platinum, chromium, nickel, titanium, and zinc. These may be used alone or in combination. Alternatively, it may be laminated. The film thickness of the metal layer 112 is preferably about 1 nm to 10 μm. Moreover, it is preferable that the reflectance of the metal layer 112 formed on the lower surface of the wire 106 is 50% or more with respect to light (blue light) in a wavelength range of 430 nm to 490 nm. Note that the material of the metal layer 112 is not limited to the above metal, and may be Cu, Al, or the like, for example.

<3-6. Die Bond Member (Resin Composition and Metal Bonding Member)>
The resin composition (die-bond member) used in the die-bonding process is a bonding member for bonding the light-emitting element 104, the protective element 105, etc. via the silver-containing metal 103 on the conductive members 102A and 102B in the recess 109 of the base 101. is there.
As described in the chapter of the method for manufacturing a light-emitting device, after the light-emitting element 104 is placed on the resin composition, heating is performed at a temperature at which at least a part of the resin composition volatilizes.

  For example, when the resin composition contains a thermosetting resin, it is desirable that the light emitting element 104 be placed on the resin composition and then heated to a temperature higher than the temperature at which the thermosetting resin is cured. By heating in this way, the light emitting element 104 can be bonded and fixed by the thermosetting resin contained in the resin composition.

  You may make the resin composition contain metal powders, such as silver, gold | metal | money, palladium, and the other electroconductive member. In this way, the light emitting element 104 and the silver-containing metal 103 can be electrically connected while the light emitting element 104 is bonded and fixed. Furthermore, the resin composition may contain a solvent for adjusting the viscosity and various additives. In addition, when a metal powder is contained, the resin composition can be used as a metal bonding member. In the case where a conductive member is contained, the resin composition can be used as a conductive wire bonding member that conducts to the light emitting element 104.

  Moreover, the following two are mentioned as a form in which a die-bonding member contains both a resin composition and a metal joining member by another member. For example, when the resin composition contains rosin and a metal bonding member made of a metal having a low melting point is provided on the back surface of the light-emitting element 104 or the surface of the silver-containing metal 103 bonded to the resin composition, After the light-emitting element 104 is placed on the composition, it is desirable to heat to a temperature at which the metal having a low melting point melts. Similarly, when the resin composition contains rosin and a metal having a low melting point, and a metal film (metal bonding member) such as a silver reflective film is provided on the back surface of the light-emitting element 104 bonded to the resin composition. In this case, after the light emitting element 104 is mounted on the resin composition, it is preferable to heat the metal having a low melting point to a temperature at which the metal melts. By doing in this way, the light emitting element 104 and the silver containing metal 103 can be firmly fixed and conducted by metal bonding using a metal having a low melting point. Also in this case, the resin composition may further contain a solvent for adjusting the viscosity, various additives, an activator, and the like.

  Moreover, when a part of resin composition volatilizes and lose | disappears by heating, you may remove the resin composition which remained after heating by washing | cleaning etc. In particular, when the resin composition contains rosin, it is preferably washed. As the cleaning liquid, a glycol ether organic solvent or the like is preferable.

  As the die bond member, for example, depending on the material of the light emitting element 104, the conductive material or the insulating material can be used. For example, as in the specific example (B2), an insulating sapphire substrate is used for the substrate 104a (see FIG. 4) of the light-emitting element 104, and a nitride semiconductor layer is stacked on the substrate, thereby forming a stacked semiconductor structure 104b (FIG. 4) to form the light emitting element 104, either an insulating die-bonding member or a conductive die-bonding member can be used. Further, for example, as in the specific example (B1), in the case where a conductive SiC substrate or the like is used for the substrate 104a (see FIG. 4) of the light-emitting element 104, a conductive die-bonding member is used. The metal 103 and the light emitting element 104 can be made conductive.

  An epoxy resin, a silicone resin, or the like can be used as the insulating die bond member. In the case of using these resins, a metal layer having a high reflectance such as an Ag film can be provided on the back surface of the light emitting element 104 in consideration of deterioration due to light or heat from the light emitting element 104. In this case, an evaporation method, a sputtering method, a method for bonding thin films, or the like can be used.

As the conductive die bond member, a conductive paste such as silver, gold, or palladium, solder such as Au—Sn eutectic, or a brazing material such as a metal having a low melting point can be used.
Further, among these insulating and conductive die-bonding members, in particular, when a translucent die-bonding member is used, it contains a fluorescent member that absorbs light from the light-emitting element 104 and emits light of different wavelengths. It can also be made.

<3-7. Sealing member>
The sealing member 108 is a member that protects the light emitting element 104, the wire 106, and the like placed in the concave portion 109 of the base 101 from dust, moisture, external force, and the like, and is a translucent material that can transmit light from the light emitting element 104. Those having properties are preferred. Specific examples of the material of the sealing member 108 include a silicone resin, an epoxy resin, and a urea resin. In addition to such materials, for example, a colorant, a light diffusing agent, a filler, a wavelength conversion member (fluorescent member), and the like can be contained.

  The filling amount of the sealing member 108 may be an amount that covers the electronic components such as the light emitting element 104 and the protective element 105, the wire 106, and the like. In the case where the filling amount of the sealing member 108 is minimized, the surface of the sealing member 108 is formed in a substantially flat shape as illustrated. Note that in the case where the sealing member 108 has a lens function, the surface of the sealing member 108 may be raised so as to have a shell shape or a convex lens shape.

<3-8. Wire>
The wire 106 connects the electrode terminal 104 c (see FIG. 4) of the light emitting element 104 and the conductive members 102 </ b> A and 102 </ b> B disposed in the recess 109 of the base 101 via the silver-containing metal 103. Examples of the material of the wire 106 include metals such as gold, copper, platinum, and aluminum, and alloys thereof. In particular, it is preferable to use gold having excellent thermal resistance.

<3-9. Wavelength conversion member>
The sealing member 108 may include a fluorescent member that emits light having a different wavelength by absorbing at least part of light from the light emitting element 104 as a wavelength conversion member. As the fluorescent member, it is better to convert the light from the light emitting element 104 into a longer wavelength. The fluorescent member may be formed of a single type of fluorescent material or the like, or may be formed of a single layer in which two or more types of fluorescent material are mixed, or contains one type of fluorescent material, etc. Two or more single layers may be stacked, or two or more single layers each of which is mixed with two or more kinds of fluorescent substances may be stacked.

As the fluorescent member, for example, any member that absorbs light from a light emitting element having a nitride semiconductor as a light emitting layer and converts the light into light having a different wavelength may be used.
As the fluorescent material, for example, a nitride-based phosphor or an oxynitride-based phosphor that is mainly activated by a lanthanoid element such as Eu or Ce can be used. More specifically, it is preferably at least any one or more selected from the groups described in the following (D1) to (D3).
(D1) Alkaline earth halogen apatite, alkaline earth metal borate, alkaline earth metal aluminate, alkaline earth metal, mainly activated by lanthanoids such as Eu and transition metal elements such as Mn Fluorescent substance such as sulfide, alkaline earth metal thiogallate, alkaline earth metal silicon nitride, germanate, etc. (D2) Rare earth aluminate, rare earth silicate, alkali mainly activated by lanthanoid elements such as Ce Phosphors such as earth metal rare earth silicates (D3) Phosphors such as organic or organic complexes mainly activated by lanthanoid elements such as Eu

Among these, a YAG (Yttrium Aluminum Garnet) phosphor, which is a rare earth aluminate phosphor mainly activated by a lanthanoid element such as Ce in (D2), is preferable. The YAG phosphor is represented by the following composition formula (D21) to (D24).
(D21) Y ₃ Al ₅ O ₁₂ : Ce
_{(D22) (Y 0.8 Gd 0.2} ) 3 Al 5 O 12: Ce
_{(D23) Y 3 (Al 0.8} Ga 0.2) 5 O 12: Ce
(D24) (Y, Gd) ₃ (Al, Ga) ₅ O ₁₂ : Ce

For example, part or all of Y may be substituted with Tb, Lu, or the like. _{Specifically, Tb 3 Al 5 O 12:} Ce, Lu 3 Al 5 O 12: may be Ce or the like. Furthermore, phosphors other than the above-described phosphors having the same performance, function, and effect can be used.

<3-10. Light emitting element>
In the present embodiment, it is preferable to use a light emitting diode as the light emitting element 104. The light emitting element 104 can be selected from any wavelength. For example, in the case of using a blue (light with a wavelength of 430 nm to 490 nm) or green (light with a wavelength of 490 nm to 570 nm) light emitting element, ZnSe or a nitride-based semiconductor (In _X Al _Y Ga _1-XY N, 0 ≦ X, 0 ≦ Y, X + Y ≦ 1), and those using GaP can be used. As a red light emitting element (light having a wavelength of 620 nm to 750 nm), GaAlAs, AlInGaP, or the like can be used. Furthermore, a semiconductor light emitting element made of a material other than this can also be used. The composition, emission color, size, number, and the like of the light-emitting element to be used can be appropriately selected depending on the purpose.

  When an insulating substrate is used as the substrate 104a (see FIG. 4) of the light-emitting element 104, a metal film is provided on the insulating substrate, and the metal film side is placed on the conductive members 102A and 102B on which the silver-containing metal 103 is formed. It is preferable to make it join.

The light emitting element 104 can select various emission wavelengths depending on the material of each semiconductor layer of the stacked semiconductor structure 104b (see FIG. 4) and the mixed crystal degree thereof. For example, in the case of manufacturing a light-emitting device in which a fluorescent material is contained in the resin composition 111 or the sealing member 108, a nitride semiconductor (In _X Al _Y Ga) capable of emitting a short wavelength is used as a semiconductor used for the light-emitting layer. _1-X—YN , 0 ≦ X, 0 ≦ Y, and X + Y ≦ 1) may be mentioned as preferable examples for efficiently exciting the fluorescent substance.

<3-11. Metal film>
A metal film that can be formed on the lower surface (back surface) of the light-emitting element 104 can function as, for example, the reflective layer 121, the barrier layer 122, the adhesive layer 123, and the like illustrated in FIG.
The reflective layer 121 is a layer that efficiently reflects the light emitted by the light emitting element 104 to the inside of the substrate 104a or the stacked semiconductor structure 104b. Thus, light can be extracted to the outside from another exposed end surface of the light emitting element 104. As specific materials, Ag, Al, Rh, Pt, Pd, or the like is preferably used. For example, when silver or a silver alloy is used, an element with high reflectivity and good light extraction can be obtained.

  The barrier layer 122 is a layer for preventing diffusion of components used for forming the die bond member. As specific materials, materials having a high melting point such as W and Mo, Pt, Ni, Rh, Au and the like are preferable.

  The adhesive layer 123 is a layer that adheres the light emitting element 104 to the base 101. Specific materials include In, Pb—Pd, Au—Ga, Au and Ge, Si, In, Zn, and Sn, Al and Zn, Ge, Mg, Si, and In, Cu And an alloy of Ge and In, an Ag-Ge alloy, and a Cu-In alloy. Preferable examples include eutectic alloy films, such as an alloy mainly composed of Au and Sn, an alloy mainly composed of Au and Si, and an alloy mainly composed of Au and Ge. Of these, AuSn is particularly preferable.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to this, It can implement variously in the range which does not change the meaning. For example, in the light emitting device 100, the areas of the reflective layer 121, the barrier layer 122, and the adhesive layer 123 disposed on the lower surface side of the light emitting element 104 are smaller than the area of the lower surface of the light emitting element 104. However, the present invention is not limited to this. For example, as in the light emitting device 100A illustrated in FIG. 9, the area of the reflective layer 121, the barrier layer 122, and the adhesive layer 123 disposed on the lower surface side of the light emitting element 104 is modified to be equal to the area of the light emitting element 104. can do. Note that FIG. 9 shows a cross section of each layer having the same area, and therefore, the width of the reflective layer 121, the barrier layer 122, and the adhesive layer 123 is substantially equal to the width of the light emitting element 104 in a cross sectional view. .

In the light emitting device 100A of this modification, for example, the insulating member 110 formed by a vacuum process can cover the side surfaces of the reflective layer 121, the barrier layer 122, and the adhesive layer 123. Therefore, to reduce the coverage area of the metal layer 112, it can reduce the amount of the metal layer 1 12. In this case, the metal layer 112 mainly covers the lower surface (back surface) of the wire 106 and the pinholes of the insulating member 110 provided on the silver-containing metal 103. Note that a metal film such as the reflective layer 121 is not necessarily provided on the lower surface side of the light-emitting element 104.

  In addition, the light emitting device 100 according to the embodiment includes the surface mount type (face-up) light emitting element 104. For example, as in the light emitting device 100B illustrated in FIGS. A face-down light emitting element 104 may be provided. The light emitting device 100 </ b> B according to this modification includes two light emitting elements 104. Each light emitting element 104 is fixed and electrically connected to the silver-containing metal 103 on the conductive members 102 </ b> A and 102 </ b> B in the recess 109 through an adhesive layer 123 of AuSn that is a metal eutectic.

  In addition, as shown in FIG. 11, for example, a metal layer 112 other than silver is formed in a portion where the insulating member 110 formed by a vacuum process cannot wrap around behind the light emitting element 104 due to the straightness of sputtering. Is formed. Specifically, the metal layer 112 covers the side surface of the adhesive layer 123 disposed on the lower surface side of the light emitting element 104 as a conductor portion in which the insulating member 110 is not formed behind the light emitting element 104. Yes. In the case of such a face-down type, the light emitting element can be wireless, light absorption by the wire can be prevented, and light can be efficiently extracted from the light emitting surface side.

  Moreover, although the light emitting device 100 according to the embodiment includes the light emitting element 104 that outputs light in the visible light region, the light emitting device 100 may include a light emitting element that outputs ultraviolet light or infrared light. Moreover, although the light emitting device 100 according to the embodiment includes the light emitting element 104 and the protection element 105, electronic components such as a light receiving element can also be mounted.

  Further, although the light emitting device 100 according to the above embodiment is provided with the recess 109 in the base 101, the light emitting element 104 may be placed without providing the recess.

  Moreover, this specification does not specify the member shown by the claim as the member of embodiment by any means. In particular, the dimensions, materials, shapes, relative arrangements, and the like of the component parts described in the embodiments are described with the intention of limiting the scope of the present invention only to that unless otherwise specified. It's just an illustrative example. Note that the size, film thickness, positional relationship, and the like of the members shown in each drawing may be exaggerated for clarity of explanation.

  Since the light emitting device according to the present invention can suppress deterioration of the silver-containing metal, it can efficiently reflect the light from the light emitting element, and is a light emitting device excellent in light extraction efficiency. It can also be used in backlights for lighting fixtures, displays, liquid crystal displays, as well as image reading devices and projector devices in facsimiles, copiers, scanners, and the like.

DESCRIPTION OF SYMBOLS 100,100A, 100B Light-emitting device 101 Base | substrate 101A Base | substrate exposed part 101B Side wall of a recessed part 101C Upper surface of base | substrate 102A, 102B Conductive member 103 Silver containing metal 104 Light-emitting element 104a Substrate 104b Laminated semiconductor structure 104c Electrode terminal 105 Protection element 106 Wire 107 Cathode mark 108 Sealing member 109 Recess 110 Insulating member 111 Resin composition 112 Metal layer 121 Reflective layer 122 Barrier layer 123 Adhesive layer 131 Pinhole

Claims (9)

A substrate;
A conductive member provided on the substrate;
A silver-containing metal provided on at least a part of the conductive member;
A light emitting element mounted on the substrate;
On the surfaces of the light emitting element and the silver-containing metal, an insulating member provided so as to cover at least a part of the silver-containing metal and silver provided so as to cover a conductor portion not covered with the insulating member A metal layer containing a metal other than
A light emitting device comprising:   A wire that electrically connects a portion to be an electrode of the conductive member and an electrode terminal of the light emitting element; the insulating member is formed on an upper surface of the wire; and the metal layer is formed on a lower surface of the wire. The light emitting device according to claim 1, wherein the light emitting device is formed.   The light emitting device according to claim 2, wherein the reflectance of the metal layer formed on the lower surface of the wire is 50% or more with respect to light in a wavelength region of 430 nm to 490 nm.   The light emitting device according to claim 2, further comprising a sealing member that further covers the light emitting element and the wire.   5. The light emitting device according to claim 1, further comprising a reflective layer having a smaller area on the lower surface side of the light emitting element than the lower surface of the light emitting element. A substrate;
A conductive member provided on the substrate;
A light emitting element mounted on the substrate;
A wire for electrically connecting a portion to be an electrode of the conductive member and an electrode terminal of the light emitting element;
An insulating member provided to cover the light emitting element and the wire from above;
A metal layer containing a metal other than silver provided so as to cover a portion where the insulating member is not formed on the surface of the light emitting element and the wire;
A light emitting device comprising:   The metal layer is a metal selected from the group consisting of ruthenium, rhodium, palladium, osmium, iridium, platinum, chromium, nickel, titanium, and zinc, or an alloy containing at least the metal. The light emitting device according to claim 6. A die bonding step of bonding a light emitting element to a substrate provided with a conductive member at least partially coated with a silver-containing metal;
An insulating member forming step of forming an insulating member on a part of the surface of the light emitting element and the silver-containing metal so as to cover the light emitting element and the silver-containing metal ;
A metal layer forming step of forming a metal layer containing a metal other than silver by electrolytic plating so as to cover the conductor portion not covered with the insulating member;
A method for manufacturing a light-emitting device, comprising: After the die bonding step, it has a wire bonding step of electrically connecting a portion to be an electrode of the conductive member via the silver-containing metal and an electrode terminal of the light emitting element with a wire,
In the insulating member forming step, an insulating member is formed so as to cover the light emitting element, the silver-containing metal and the wire from above,
In the metal layer forming step, a metal layer containing a metal other than silver is formed by electrolytic plating so as to cover a portion where the insulating member is not formed on the surface of the light emitting element, the silver-containing metal, and the wire. A method for manufacturing a light emitting device according to claim 8.

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