Abstract:
In semiconductor light-emitting devices in which a light-emitting layer is formed on one surface of a substrate, and an n-side electrode and a p-side electrode are formed over the same surface of the substrate as the light-emitting layer, heat generated by a semiconductor light-emitting element needs to be dissipated to a submount. However, it is extremely complicated to fabricate connection members serving also as heat dissipating members and to control fabrication of the connection members, according to semiconductor light-emitting elements having electrodes of various sizes and shapes. By increasing the density of p-side bumps near the n-side electrode, the heat transfer area from the semiconductor light-emitting element to the submount is increased near the n-side electrode, whereby the heat dissipation effect is enhanced.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to semiconductor light-emitting devices, and more particularly to semiconductor light-emitting devices in which a semiconductor light-emitting element, which has an n-side electrode and a p-side electrode over one surface of a substrate, is placed on a submount. 
       BACKGROUND ART 
       [0002]    Semiconductor light-emitting elements for use in light-emitting diodes and laser diodes are produced by forming a light-emitting layer on a sapphire or GaN substrate. One type of semiconductor light-emitting element, which has a current supplying electrode formed on one surface of a substrate, emits light from the other surface of the substrate, on which the light-emitting layer is not formed. This type of semiconductor light-emitting element is capable of emitting a large amount of light since no electrode need be provided on the light-emitting surface for emitting light. 
         [0003]    In recent years, semiconductor light-emitting elements have been used for lighting applications. The aforementioned type of semiconductor light-emitting element has been increasingly used, and power supply has been increased in order to increase the amount of light emission. This type of semiconductor light-emitting element, which has a current supplying electrode formed on one surface of the substrate, is typically mounted on a part for supplying a current, called a submount, and dissipates heat to the submount. A current-carrying electrode is provided between the semiconductor light-emitting element and the submount, and this electrode often serves also as a heat dissipating member. 
         [0004]    Patent Document 1 discloses a semiconductor light-emitting device in which a bump electrode is provided in each light-emitting element in order to increase heat dissipation efficiency. Each bump electrode is connected to a corresponding anode electrode (which is a p-side electrode), and is sized so as to cover substantially the entire surface of the anode electrode (see claim 3 of Patent Document 1). 
         [0005]    Patent Document 2 also discloses that first and second large bumps are provided as electrodes in order to enhance a heat dissipation effect, and the total planar cross-sectional area of the large bumps is at least 30% of the planar cross-sectional area of a semiconductor light-emitting element (see claim 2 of Patent Document 2). The first and second bumps are bumps connected to a p-side electrode and an n-side electrode, respectively. 
       Citation List 
     Patent Document 
       [0006]    PATENT DOCUMENT 1: Japanese Published Patent Application No. 2005-64412 
         [0007]    PATENT DOCUMENT 2: Japanese Published Patent Application No. 2003-218403 
       SUMMARY OF THE INVENTION 
     Technical Problem 
       [0008]    Supplying a large current to a semiconductor light-emitting element generates heat since the semiconductor light-emitting element releases excess energy, which fails to be converted to light, as heat. The type of semiconductor light-emitting element, which has a current supplying electrode formed on one surface of a substrate, needs to dissipate heat via a connection electrode that is provided between the semiconductor light-emitting element and the submount. 
         [0009]    The amount of heat dissipation is determined by the contact area, and the thermal conductivity of the material of the connection electrode. Thus, increasing the contact area as in the above Patent Documents is reasonable in order to enhance the heat dissipation effect. However, there are various types of semiconductor light-emitting elements, and manufactures need to fabricate semiconductor light-emitting elements of various sizes according to applications. 
         [0010]    In this case, fabricating connection electrodes according to the individual electrode shapes of semiconductor light-emitting elements increases the number of kinds of parts, complicating the process control. The present invention was developed in view of this problem. 
       Solution To The Problem 
       [0011]    In order to solve the above problem, a semiconductor light-emitting device according to the present invention includes: a submount having a p-side extended electrode and an n-side extended electrode, which are formed on one surface thereof; a p-side connection member formed on an upper surface of the p-side extended electrode, and an n-side connection member formed on an upper surface of the n-side extended electrode; and a semiconductor light-emitting element having a light-emitting layer on one surface thereof, and having a p-side electrode and an n-side electrode on one surface of the light-emitting layer, the p-side electrode being electrically connected to the p-side extended electrode via the p-side connection member, and the n-side electrode being electrically connected to the n-side extended electrode via the n-side connection member, wherein multiple ones of the p-side connection member are provided, the one surface of the light-emitting layer is formed by a first region located within a predetermined distance from the n-side electrode, and a second region other than the first region, and the predetermined distance is such that an area of the first region is one third of that of the second region, and a sum x of bottom areas of the p-side connection members located in the first region is larger than one third of a sum y of bottom areas of the p-side connection members located in the second region. 
       Advantages of the Invention 
       [0012]    With the above configuration, a relatively large number of p-side connection members are located near the n-side connection member, thereby enhancing the heat dissipation effect near the n-side connection member. The above configuration also eliminates the need to individually fabricate electrodes capable of dissipating heat, according to the types of semiconductor light-emitting devices. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    [ FIG. 1 ]  FIG. 1A  is a schematic cross-sectional view of a semiconductor light-emitting device according to an embodiment, and  FIG. 1B  is a schematic plan view thereof. 
           [0014]    [ FIG. 2 ]  FIGS. 2A and 2B  are diagrams showing the configuration of a semiconductor light-emitting device of a comparative example of the embodiment. 
           [0015]    [ FIG. 3 ]  FIGS. 3A and 3B  are diagrams illustrating a variation of the semiconductor light-emitting device of the embodiment. 
           [0016]    [ FIG. 4 ]  FIGS. 4A and 4B  are diagrams illustrating variations of the semiconductor light-emitting device of the embodiment. 
           [0017]    [ FIG. 5 ]  FIGS. 5A and 5B  are diagrams illustrating variations of the semiconductor light-emitting device of the embodiment. 
           [0018]    [ FIG. 6 ]  FIGS. 6A and 6B  are diagrams showing the configuration of a semiconductor light-emitting element. 
           [0019]    [ FIG. 7 ]  FIGS. 7A and 7B  are diagrams showing the configuration of a submount. 
       
    
    
     DESCRIPTION OF REFERENCE CHARACTERS 
       [0000]    
       
           1  Semiconductor Light-Emitting Device 
           10  Semiconductor Light-Emitting Element 
           11  Substrate 
           12  n-Type Layer 
           13  Active Layer 
           14  p-Type Layer 
           15  Light-Emitting Layer 
           15   a - 15   e  Light-Emitting Layer 
           16  n-Side Electrode 
           16   a - 16   e  n-Side Electrode 
           17  p-Side Electrode 
           17   a - 17   e  p-Side Electrode 
           21  Submount 
           22  n-Side Extended Electrode 
           23  p-Side Extended Electrode 
           24  n-Side Bump 
           24   a - 24   e  n-Side Bump 
           25  p-Side Bump 
           25   a - 25   e  p-Side Bump 
           100 - 105  First Region 
           200 - 205  Second Region 
       
     
       DESCRIPTION OF EMBODIMENTS 
       [0041]      FIGS. 1A-1B  show an example semiconductor light-emitting device  1 .  FIG. 1A  is a cross-sectional view, and  FIG. 1B  is a plan view. The semiconductor light-emitting device  1  is structured so that a semiconductor light-emitting element  10  is fixed to a submount  21 . 
         [0042]    The semiconductor light-emitting element  10  is structured so that a light-emitting layer  15  including an n-type layer and a p-type layer is laminated on a substrate  11 . An n-side electrode  16  is formed on the n-type layer, and a p-side electrode  17  is formed on the p-type layer. A surface of the substrate  11 , on which the light-emitting layer  15  is not formed, serves as a light-emitting surface  36  for emitting light. In  FIG. 1A , the n-side electrode  16  and the p-side electrode  17  are formed on the lower surface (one surface) of the semiconductor light-emitting element  10 . 
         [0043]    Extended electrodes  22 ,  23  are formed on one surface (the upper surface) of the submount  21 . The extended electrodes  22 ,  23  are electrodes for supplying a current to the semiconductor light-emitting element  10 . The n-side extended electrode  22  is connected to the n-type layer of the semiconductor light-emitting element  10 , and the p-side extended electrode  23  is connected to the p-type layer of the semiconductor light-emitting element  10 . 
         [0044]    N-side bumps  24  are formed on the upper surface of the n-side extended electrode  22  so as to be connected to the n-side electrode  16  of the semiconductor light-emitting element  10 . P-side bumps  25  are formed on the upper surface of the p-side extended electrode  23  so as to be connected to the p-side electrode  17  of the semiconductor light-emitting element  10 . That is, the n-side bumps  24  are n-side connection members, and the p-side bumps  25  are p-side connection members. In  FIGS. 1A-1B , a plurality of n-side bumps and a plurality of p-side bumps are provided, and are collectively represented by reference characters  24 ,  25 , respectively. Note that the respective lower surfaces of the n-side extended electrode  22  and the p-side extended electrode  23  are in contact with the upper surface of the submount  21 . 
         [0045]    The semiconductor light-emitting device  1  of  FIG. 1  has no p-type layer in a portion where the n-side electrode  16  is formed. Thus, the semiconductor light-emitting device  1  does not emit light in this portion. In order to increase luminous efficiency, the area of the portion where the n-side electrode  16  is formed needs to be as small as possible. On the other hand, since the p-side electrode  17  is formed on one surface of the light-emitting layer  15 , a portion where the p-side electrode  17  is formed may have a large area. 
         [0046]    If the n-side electrode  16  and the p-side electrode  17  have different areas from each other in this manner, a current flow is concentrated near the n-side electrode  16 . Thus, heat generation increases near the n-side electrode  16 , and the temperature in this region becomes higher than in other regions, thereby reducing the luminous efficiency. Accordingly, the heat transfer area of the semiconductor light-emitting element  10  to the submount  21  is increased near the n-side electrode  16  to enhance a heat dissipation effect near the n-side electrode  16 . 
         [0047]    More specifically, the p-side bumps  25  for conducting heat from the semiconductor light-emitting element  10  to the submount  21  are arranged so that a large number of p-side bumps  25  are located near the n-side electrode  16 , and a small number of p-side bumps  25  are located in a region away from the n-side electrode  16 . More precisely, provided that a first region  100  is a region located within a predetermined distance from the n-side electrode  16  in the one surface of the light-emitting layer  15  on which the p-side electrode  17  is formed, and a second region  200  is a region other than the first region  100  in the one surface of the light-emitting layer  15 , the sum x of the bottom areas of the p-side bumps  25  in the first region  100  and the sum y of the bottom areas of the p-side bumps  25  in the second region  200  satisfy the following relation. 
         [0000]        x/ (the area of the first region)&gt; y/ (the area of the second region) 
         [0000]    The bottom area of the p-side bump  25  refers to the area of the bottom surface of the p-side bump  25 , which is in contact with the upper surface of the p-side electrode  17 . 
         [0048]    In  FIG. 1B , the first region  100  is a region in a sector, which is located within a predetermined distance L from the n-side region  16 , and the second region  200  is a region other than the first region  100  in the one surface of the light-emitting layer  15  on which the p-side electrode  17  is formed. 
         [0049]    If the area of the first region  100  is too small relative to the area of the one surface of the light-emitting layer  15 , the heat dissipation effect may not be sufficient even if the above relation is satisfied. On the contrary, if the area of the first region  100  is too large, an excessive number of p-side bumps  25  can exist when the above relation is satisfied. Thus, the first region  100  and the second region  200  are formed so that the area of the first region  100  is one third of that of the second region  200 . This can produce a sufficient heat dissipation effect and secure a necessary and sufficient number of p-side bumps  25  when the above relation is satisfied. If the area of the first region  100  is one third of that of the second region  200 , the above relation “x/(the area of the first region)&gt;y/(the area of the second region)” is represented by “x/y&gt;⅓.” 
         [0050]    For example, if the first region  100  and the second region  200  are arranged so as to form a part of concentric circles about the n-side electrode  16 , and the area of the first region  100  is one third of that of the second region  200 , the first region  100  is within the range of a radius r from the n-side electrode  16 , and the second region  200  is located outside the first region  100 , and is within the range of a radius 2r from the n-side electrode  16 . It should be noted that the area of the first region  100  need not necessarily be exactly one third of that of the second region  200 , and may be within ±20% of one third of the area of the second region  200 . 
         [0051]    The heat dissipation effect near the n-side electrode  16  is enhanced if “x/(the area of the first region)” is larger than “y/(the area of the second region).” In order to further enhance the heat dissipation effect, “x/(the area of the first region)” is preferably at least 1.2 times “y/(the area of the second region),” more preferably at least 1.5 times “y/(the area of the second region),” and even more preferably at least two times “y/(the area of the second region).” In  FIG. 1B , “x/(the area of the first region)” is about three times “y/(the area of the second region).” 
         [0052]    In the semiconductor light-emitting device  1  of  FIGS. 1A-1B , the plurality of p-side bumps  25  having the same shape and the same bottom area are arranged so as to satisfy the relation “x/(the area of the first region)&gt;y/(the area of the second region).” That is, the density of the p-side bumps  25  is increased near the n-side electrode  16 , and is decreased in the region away from the n-side electrode  16 . 
         [0053]    In a comparative semiconductor light-emitting device  1 ′ shown in  FIGS. 2A-2B , the density of p-side bumps  25 ′ is constant both near the n-side electrode  16  and in a region away from the n-side electrode  16 . Thus, the heat dissipation effect is not enhanced near the n-side electrode  16  as in the semiconductor light-emitting device  1  of  FIGS. 1A-1B . Note that although only one n-side bump  24 ′ is provided in  FIGS. 2A-2B , three n-side bumps  24  are provided in  FIGS. 1A-1B , and the total bottom area of the n-side bumps  24  is larger than the bottom area of the n-side bump  24 ′ in  FIGS. 2A-2B . In this regard as well, the semiconductor light-emitting device  1  of  FIGS. 1A-1B  has a higher heat dissipation effect near the n-side electrode  16  than the comparative semiconductor light-emitting device  1 ′ of  FIGS. 2A-2B . 
         [0054]    Modifications will be described below with reference to a semiconductor light-emitting element. 
         [0055]      FIG. 3A  is a diagram showing only the semiconductor light-emitting element of  FIG. 1B . 
         [0056]    In a semiconductor light-emitting element of  FIG. 3B , two n-side electrodes  16   a,    16   a  are formed in two diagonally opposite corners of a rectangular substrate  11 . Thus, two first regions  101 ,  101  corresponding to the two n-side electrodes  16   a,    16   b  are defined on one surface of a light-emitting layer  15   a,  and a second region  201  is located between the first regions  101 ,  101 . The sum of the areas of the two first regions  101 ,  101  is one third of the area of the second region  201 . In this example, the sum x of the bottom areas of p-side bumps  25   a  located in the two first regions  101 ,  101  is about 1.2 times the sum y of the bottom areas of p-side bumps  25   a  located in the second region  201 , and x/y&gt;⅓. Three n-side bumps  24   a  are positioned on each n-side electrode  16   a,    16   a.  The p-side bumps  25   a  are connected to a p-side electrode  17   a.    
         [0057]    In semiconductor light-emitting elements shown in  FIGS. 4A-4B , one or two n-side electrodes  16   b,    16   c  are formed on one or two sides of a substrate  11 . 
         [0058]    In the semiconductor light-emitting element of  FIG. 4A , one n-side electrode  16   b  is formed in the middle of one side of the rectangular substrate  11 . In this example, a first region  102  in one surface of a light-emitting layer  15   b  is substantially semicircular, and the area of the first region  102  is one third of that of a second region  202 . The sum x of the bottom areas of p-side bumps  25   b  located in the first region  102  is about the same as the sum y of the bottom areas of p-side bumps  25   b  located in the second region  202 , and x/y&gt;⅓. Three n-side bumps  24   b  are positioned on the n-side electrode  16   b.  The p-side bumps  25   b  are connected to a p-side electrode  17   b.    
         [0059]    In the semiconductor light-emitting element of  FIG. 4B , two n-side electrodes  16   c,    16   c  are formed in the middle of two opposite sides of a rectangular substrate  11 . Thus, two first regions  103 ,  103  corresponding to the two n-side electrodes  16   c,    16   c  are defined on one surface of a light-emitting layer  15   c,  and a second region  203  is located between the first regions  103 ,  103 . The sum of the areas of the two first regions  103 ,  103  is one third of that of the second region  203 . The sum x of the bottom areas of p-side bumps  25   c  located in the two first regions  103 ,  103  is about 0.6 times the sum y of the bottom areas of p-side bumps  25   c  located in the second region  203 , and x/y&gt;⅓. Three n-side bumps  24   c  are positioned on each n-side electrode  16   c,    16   c.  The p-side bumps  25   c  are connected to a p-side electrode  17   c.    
         [0060]    In a semiconductor light-emitting element of  FIG. 5A , an n-side electrode  16   d  is formed in the center of a rectangular substrate  11 . A first region  104  in one surface of a light-emitting layer  15   d  is circular, and the area of the first region  104  is one third of that of a second region  204 . The sum x of the bottom areas of p-side bumps  25   d  located in the first region  104  is about 1.7 times the sum y of the bottom areas of p-side bumps  25   d  located in the second region  204 , and x/y&gt;⅓. Four n-side bumps  24   d  are positioned on the n-side electrode  16   d.  The p-side bumps  25   d  are connected to a p-side electrode  17   d.    
         [0061]    In a semiconductor light-emitting element of  FIG. 5B , an n-side electrode  16   e  is formed in one corner of a rectangular substrate  11  as in  FIG. 3A . A first region  105  and a second region  205  in one surface of a light-emitting layer  15   e  are the same in shape and size as the first region  100  and the second region  200  of the semiconductor light-emitting element of  FIG. 1B . The semiconductor light-emitting element of  FIG. 5B  is different from that of  FIG. 1B  in that the semiconductor light-emitting element of  FIG. 5B  has two types of p-side bumps  25   e,    25   z  having different sizes from each other. The bottom area of the larger p-side bump  25   z  is about 30 times that of the smaller p-side bump  25   e.  The semiconductor light-emitting element of  FIG. 5B  has two larger p-side bumps  25   z,  and most of the bottom surfaces of the p-side bumps  25   z  is located in the first region  105 . The sum x of the bottom areas of the p-side bumps  25   e,    25   z  located in the first region  105  is about 1.4 times the sum y of the bottom areas of the p-side bumps  25   e,    25   z  located in the second region  205 , and x/y&gt;⅓. Three n-side bumps  24   e  are positioned on the n-side electrode  16   e.  The p-side bumps  25   e,    25   z  are connected to a p-side electrode  17   e.    
         [0062]    As described above, in the above example semiconductor light-emitting device, the density of the bottom areas of the p-side bumps is higher in the vicinity of the n-side electrode than in the region away from the n-side electrode. This enhances the effect of heat dissipation from the semiconductor light-emitting element to the submount. 
         [0063]    Possible materials of the example semiconductor light-emitting device will be described below. 
         [0064]      FIG. 6A  is a cross-sectional view of the semiconductor light-emitting element  10  corresponding to the semiconductor light-emitting device  1  of  FIG. 1A , and  FIG. 6B  is a plan view as viewed from the electrode plane side. The semiconductor light-emitting element  10  is formed by a substrate  11 , an n-type layer  12 , an active layer  13 , a p-type layer  14 , an n-side electrode  16 , and a p-side electrode  17 . The n-side layer  12 , the active layer  13 , and the p-side layer  14  are collectively referred to as a light-emitting layer  15 . A surface of the substrate  11 , on which the light-emitting layer  15  is not formed, serves as a light-emitting surface  36 . 
         [0065]    The substrate  11  serves to hold the light-emitting layer  15 . The substrate  11  can be made of an insulating material such as sapphire. However, it is a primary object of the above embodiment to diffuse heat that is generated by current concentration in the case where the n-side electrode  16  is provided at one or several positions on the substrate  11 . Thus, it is more preferable to use a conductive substrate as the substrate  11 . More specifically, in the case of using gallium nitride (GaN) as a base material of a light-emitting portion, it is preferable to use as the substrate  11  a conductive substrate having about the same refractive index as that of the light-emitting layer  15 , such as GaN, SiC, AlGaN, or AlN, in order to reduce reflection of light at the interface between the n-type layer  12  and the substrate  11 . In the case of using zinc oxide (ZnO) as a base material of the light-emitting portion, ZnO is preferable as a material of the substrate  11 . 
         [0066]    The n-type layer  12 , the active layer  13 , and the p-type layer  14  of the light-emitting layer  15  are sequentially laminated on the substrate  11 . Although the respective materials of the n-type layer  12 , the active layer  13 , and the p-type layer  14  are not specifically limited, each of the n-type layer  12 , the active layer  13 , and the p-type layer  14  is preferably made of a GaN compound. More specifically, the n-type layer  12 , the active layer  13 , and the p-type layer  14  are preferably made of GaN, InGaN, and GaN, respectively. Note that AlGaN or InGaN may be used as the n-type layer  12  and the p-type layer  14 . A GaN or InGaN buffer layer may further be provided between the n-type layer  12  and the substrate  11 . For example, the active layer  13  may have a multilayer structure (a quantum well structure) in which InGaN and GaN layers are alternately laminated. 
         [0067]    In this light-emitting layer  15  formed by laminating the n-type layer  12 , the active layer  13 , and the p-type layer  14 , the active layer  13  and the p-type layer  14  are removed in a part of the surface of the light-emitting layer  15  to expose the n-type layer  12 . The n-side electrode  16  is formed on the exposed n-type layer  12 . Note that in the case of the conductive substrate  11 , the n-type layer  12  may also be removed to form the n-side electrode  16  directly on the substrate  11 . The p-side electrode  17  is also formed on the p-type layer  14 . That is, the light-emitting layer  15 , and the p-side electrode  17  and the n-side electrode  16  can be formed on the same side of the substrate  11  by removing the active layer  13  and the p-type layer  14  so as to expose the n-type layer  12 . 
         [0068]      FIG. 6B  shows the semiconductor light-emitting element  10  as viewed from the side on which the n-side electrode  16  and the p-side electrode  17  are formed. In the figure, the p-side electrode  17  is shown to occupy a larger area than the n-side electrode  16 . However, the present invention is not limited to this configuration, and the area ratio between the p-side electrode  17  and the n-side electrode  16 , and the shapes of the p-side electrode  17  and the n-side electrode  16  may be changed as appropriate according to the design of the semiconductor light-emitting element. The n-side electrode  16  may be partially extended along the respective side surfaces of the remaining active layer  13  and the remaining p-side layer  14  with an insulating film therebetween, so as to partially cover the respective surfaces of the p-type layer  14  and the p-side electrode  17 . This facilitates connection to the bumps. 
         [0069]    The p-side electrode  17  is preferably an electrode made of a material having high reflectance, such as Ag, Al, or Rh, in order to reflect light emitted by the light-emitting layer  15  toward the light-emitting surface  36 . It is more desirable to provide between the p-type layer  14  and the p-side electrode  17  a thin film electrode layer such as Pt, Ni, or Co, or a light-transmitting electrode layer such as indium tin oxide (ITO) in order to reduce the ohmic contact resistance between the p-type layer  14  and the p-side electrode  17 . Al, Ti, or the like can be used as the n-side electrode  16 . It is preferable to form an Au or Al film on the respective surfaces of the p-side electrode  17  and the n-side electrode  16  in order to increase adhesion strength to the bumps. These electrodes can be formed by a vacuum deposition method, a sputtering method, or the like. 
         [0070]    The size of the semiconductor light-emitting element  10  is not specifically limited. However, the above embodiment has a heat dissipation effect especially when a large current is supplied. Thus, it is more preferable that the semiconductor light-emitting element  10  emit a larger amount of light, and have a larger total area. Specifically, it is desirable that the size of the semiconductor light-emitting element  10  be at least 600 μm by 600 μm. The semiconductor light-emitting element  10  having a larger total area can operate more like a surface emission light source. Note that although the planar shape of the semiconductor light-emitting element  10  is not limited to a square, it is often convenient to manufacture the semiconductor light-emitting element  10  having a square planar shape. 
         [0071]      FIG. 7A  is a cross-sectional view of the submount  21  and the bumps  24 ,  25  corresponding to the semiconductor light-emitting device  1  of  FIG. 1A .  FIG. 7B  is a plan view of the submount  21  as viewed from the extended electrode ( 22 ,  23 ) side. A silicon zener diode, a silicon diode, silicon, aluminum nitride, alumina, other ceramic material, or the like can be used as the submount  21 . 
         [0072]    Although gold, gold-tin, solder, an indium alloy, a conductive polymer, or the like can be used as a material of the bumps  24 ,  25 , gold or a material mainly containing gold is especially preferable. With these materials, the bumps  24 ,  25  can be formed by a plating method, a vacuum deposition method, a screen printing method, a droplet injection method, a wire bump method, or the like. 
         [0073]    For example, in the wire bump method, gold bumps are formed by bonding one ends of gold wires to the extended electrodes  22 ,  23  on the submount  21  by a bonder, and cutting the wires. In the droplet injection method, a volatile solvent, having dispersed therein fine nanoparticles of a highly conductive material such as gold, is printed by a method similar to an inkjet printing method, and the solvent is volatilized and removed to form bumps as aggregations of the nanoparticles. 
         [0074]    A method for individually forming the bumps  24 ,  25  is especially suitable for forming the bumps of the above semiconductor light-emitting devices, since it is often easy to change the formation positions (the positions where the bumps are to be formed) by changing a program of a forming apparatus. 
         [0075]    Note that although the bumps are described above in detail as the connection members, the connection members are not limited to the bumps. 
         [0076]    Throughout the specification, Al represents aluminum, N represents nitrogen, C represents carbon, O represents oxygen, Ag represents silver, Rh represents rhodium, Pt represents platinum, Ni represents nickel, Co represents cobalt, Ti represents titanium, Au represents gold, Ga represents gallium, In represents indium, Zn represents zinc, and Si represents silicon. 
       INDUSTRIAL APPLICABILITY 
       [0077]    The present invention can be used for semiconductor light-emitting elements in which an n-side electrode and a p-side electrode are provided over one surface of a substrate, and the other surface of the substrate serves as a light-emitting surface, and semiconductor light-emitting devices using the same.