JP2011114244A - Element mounting body and light emitting body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an element mounting body in which separation of electrodes or the like is suppressed. <P>SOLUTION: The element mounting body for mounting a functional element, comprises: an insulating body having a flat part and a projecting part projecting from the flat part; and conductive layer electrically connecting to the functional element and applied to a surface of the projecting part. The projecting part has a top surface approximately parallel to the flat part and a recessed surface at a corner from a side surface continuous to the flat part to the top surface. The conductive layer is applied to a region from the top surface to the recessed surface of the projecting part. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to an element mounting body and a light emitting body.

  For example, a functional element such as a light emitting diode (LED) is usually mounted and used in a package provided with an electrode for supplying power to the functional element. The following Patent Documents 1 and 2 describe an example of an element mounting body on which a light emitting element is mounted. In the element mounting body described in Patent Documents 1 and 2, electrodes are formed on the surface of a substrate on which the element is mounted, and includes an inclined surface provided so as to surround the element mounting area. This inclined surface functions as a reflecting surface for efficiently collecting light emitted from the light emitting element in a direction substantially perpendicular to the mounting surface on which the element is mounted. In the element mounting body described in Patent Documents 1 and 2, electric power is supplied to the light emitting element through an electrode continuous from the mounting area to the slope. As the substrate of the light emitting element mounting body, ceramics or the like having high insulation and reflectivity and high mechanical strength is used. For example, for forming an electrode on the surface of a substrate mainly composed of ceramics, a so-called printed wiring technique is used in which a metallized layer is formed by applying and baking an electrode paste.

JP 2005-277380 A JP 2002-246650 A

As the light-emitting element mounting body is miniaturized, it is required to form electrodes with a finer size with higher accuracy in forming electrodes by printed wiring. However, the conventional printed wiring technology has a limit to miniaturization and high accuracy. In particular, when the mounting body has a relatively complicated three-dimensional structure, such as an inclined surface (reflection surface) of the light emitting element mounting body, for example, wiring that is continuous between the mounting surface of the light emitting element and the reflecting surface is It was difficult to form with the desired dimensional accuracy. In addition, light emitting elements such as LEDs generate relatively large heat during light emission. For example, an electrode made of metal has a larger coefficient of thermal expansion than an insulating base made of ceramics, for example. In a light-emitting element mounting body in which an electrode layer is simply formed on the surface of an insulating base made of ceramics by conventional printed wiring technology, thermal expansion and contraction of the electrode and the base accompanying the light emission and extinction of the light-emitting element Due to the difference in the ratio, there is a problem that the electrode is easily peeled off from the substrate. The present invention has been devised to solve such problems in the prior art.

In order to solve the above-described problem, the present application provides a functional element mounting body on which a functional element is mounted, an insulating base including a flat portion on a side where the functional element is disposed, and the base of the base A conductive layer electrically connected to the functional element, provided on the side of the plane portion; and the base protrudes from the plane portion, and has a top surface substantially parallel to the plane portion and the plane portion. A protruding portion having a continuous side surface, and the protruding portion is provided with a recess at a corner portion extending from the top surface to the side surface of the protruding portion, and the conductor layer is formed from the top surface. Provided is an element mounting body characterized by being attached to a concave portion.

  Moreover, the light emitting body characterized by comprising the above-described element mounting body and the light emitting element disposed on the conductor layer of the element mounting body is also provided.

  In the element mounting body of the present invention, the electrodes are controlled to a predetermined shape with high accuracy, and the operation reliability is relatively high. Further, electrode peeling and the like due to temperature fluctuations are suppressed.

(A) is a schematic perspective view of the LED package which is one Embodiment of the element mounting body of this invention, (b) is a schematic perspective view of the base | substrate of the LED package shown to Fig.1 (a). . It is a figure explaining the LED package shown in FIG. 1, (a) is a top view, (b) is a schematic sectional drawing in the BB line shown in FIG. 2 (a), (c) is FIG. 2 (a). It is a schematic sectional drawing in the CC line shown. It is a figure explaining other embodiment of the LED package shown in FIG. 2, (a) is a schematic perspective view, (b)-(d) is a schematic sectional drawing. It is a figure explaining one Embodiment of the light-emitting body 20 of this embodiment, (a) is a schematic top view of a light-emitting body, (b) is a schematic sectional drawing in the BB line shown to Fig.2 (a), ( (c) is a schematic sectional drawing in CC line shown to Fig.2 (a).

  An embodiment of the element mounting body of the present invention will be described with reference to the drawings. 1 and 2 are schematic explanatory diagrams for explaining an LED package 10 which is an embodiment of the element mounting body of the present invention. FIG. 1A is a schematic perspective view of the LED package 10, and FIG. 1B is a schematic perspective view of the base 6 constituting the LED package 10. 2A is a top view, FIG. 2B is a schematic cross-sectional view taken along line BB shown in FIG. 2A, and FIG. 2C is a schematic view taken along line CC shown in FIG. It is sectional drawing. Moreover, FIG.2 (d) is a figure which expands and shows the broken-line part shown in FIG.2 (b).

The LED package 10 is used by mounting an LED element 2 (see FIG. 2) which is a light emitting element. The LED package 10 includes an insulating base 6, a conductive layer 8 provided on the surface of the base 6, and an electrode body 9.
The substrate 6 includes a flat portion 4, and a convex portion 18 including a slope 16 for reflecting light from the light emitting element is provided so as to surround the flat portion 4. The top surface 31 of the convex portion 18 is substantially parallel to the flat portion 4.

  The base 6 has a protruding portion 11 protruding from the flat portion 4. The protruding portion 11 includes a side surface 13 that is continuous with the flat surface portion 4, a top surface 15 that is substantially parallel to the flat surface portion 4, and a concave surface 17 that is provided at a corner from the side surface 13 to the top surface 15. The concave surface refers to a surface located in a more inner region of the protruding portion 11 than both the first virtual plane including the top surface 15 and the second virtual plane including the top portion 15. In the LED package 10, the concave surface 17 has a first inner surface 17 a substantially parallel to the top surface 15 and a second inner surface 17 b substantially parallel to the side surface 13. In the LED package 10, the protruding portion 18 is continuously provided from the flat portion 4 to the slope 16.

  Moreover, in the LED package 10, as shown in the drawing, the two protruding portions 11 are arranged so as to face each other with the wall portion 19 in between. The wall portion 19 includes a wall surface 21 that is connected to the top surface 15 and the concave surface 17 of the protruding portion 11 and is substantially perpendicular to both the top surface 15 and the concave surface 17.

  The base 6 is composed mainly of ceramics. In the LED package 10 for mounting the LED element 2, it is preferable that the ceramic is mainly composed of alumina, for example. Alumina has good reflectivity with respect to the LED element 2. In addition, a fine structure of several mm to 1 mm or less can be formed relatively easily by molding. Further, it is possible to form the electrode relatively easily using metallization technology. In these respects, alumina is preferably used as a material constituting the base 6, but other ceramic materials, resin materials, and the like can be used depending on the application, and the material of the base 6 is not particularly limited. The base 6 includes a protruding portion 11, and the protruding portion 11 has a relatively high mechanical strength.

  The conductive layer 8 is deposited from the top surface 15 to the concave surface 17 of the protruding portion 11 of the base 6. The conductive layer 8 is also attached to the wall surface 21 of the wall portion 19. The conductive layer 8 has a known multilayer metal film structure in which a plating layer is laminated on a metallized layer, for example. The conductive layer 8 is configured, for example, by laminating a Ni plating layer and an Au plating layer on a Mo—Mn metallization layer. In the formation of the conductive layer 8, for example, a known printing technique may be used in which a paste material that is a raw material of the Mo—Mn metallized layer is arranged in a predetermined shape, for example.

  In forming the conductive layer 8 using a printing technique, if the conductive layer 8 is formed on the top surface 15 of the protruding portion 11, the conductive paste member protrudes and is applied to a portion other than the top surface 15. Therefore, the conductive layer 8 can be formed on the top surface 15 with high shape accuracy. However, in this case, the conductive paste spills from the top surface 15 toward the side surface 13 and easily spreads to the plane 6. In the LED package 10, the projecting portion 11 is provided with a concave surface 17, and the conductive paste spilled from the top surface 15 to the side surface 17 is dammed by the concave surface 17, and the conductive layer 8 has high shape accuracy. It is formed with. The LED package 10 has a first inner surface 17a substantially parallel to the top surface 15, and the position of the conductive layer 8 is defined with high accuracy by the first inner surface 17a.

  The conductive layer 8 is also attached to the wall surface 21 of the wall portion 19. The conductive layer 8 attached to the two protruding portions 11 arranged so as to face each other with the wall portion 19 interposed therebetween is reliably separated by the wall portion 19. In the LED package 10, the conductive layers 8 are electrically connected between the two protruding portions 11 facing each other even when the conductive paste is disposed to such an extent that the conductive paste is applied to the concave portion 17 using the printing technique as described above. It has been deterred. In the LED package 10, the concave portion 17 and the wall portion 19 define the electrode width (lateral length in FIG. 1C), position, and shape of the conductive layer 8. Thereby, in the LED package 10, the shape and positional accuracy of the conductive layer 8 are relatively high. For example, even if the electrode width is as fine as 1 mm or less, the position and shape are defined with high accuracy.

  As shown in FIGS. 2B and 2C, the conductive layer 8 is formed along the top surface 15 of the protruding portion 11 from the flat portion 4 to the inclined surface 16 of the base 6. The electrode body 9 is formed on the top surface 21 of the protrusion 18 and is connected to the conductive layer 8.

  FIG. 3 is a diagram for explaining another embodiment of the element mounting body, where (a) is a schematic perspective view of the element mounting body of the other embodiment, and (b) to (c) are different implementations. It is a schematic sectional drawing of the element mounting body of a form. In the base body constituting the element mounting body, the concave surface 17 of the projecting portion 11 does not need to be provided continuously along the peripheral line of the top surface 15, and a plurality of the concave surfaces 17 as shown in FIG. It may be provided discretely at each location, or only one location may be provided. Further, the cross-sectional shape of the concave surface is not particularly limited, and may be entirely curved as shown in FIG. 3 (b), and a plurality of steps may be formed in a staircase shape as shown in FIG. 3 (c). Steps may be continuous. Moreover, as shown in FIG.3 (d), the structure which has a deep step part partially may be sufficient. The shape of the concave surface is not particularly limited.

  FIG. 4 is a diagram illustrating an embodiment of the light emitter 20 of the present embodiment. 4A is a schematic top view of the luminous body 20, FIG. 4B is a schematic cross-sectional view taken along line BB shown in FIG. 4A, and FIG. 4C is a diagram showing C shown in FIG. It is a schematic sectional drawing in the -C line | wire.

  The luminous body 20 is configured by arranging the LED element 2 in the LED package 10 shown in FIG. The LED element 2 is a known light-emitting diode element, and is disposed on the LED package 10 via a conductive layer 8 as shown in FIG. In the light-emitting body 2, the LED element 2 is flip-chip connected to two electrically conductive layers 8 that are electrically independent from each other. In the light emitting body 20, electric power is supplied to the LED element 2 through the conductive layer 8, and the LED element 2 emits light according to the supplied electrode.

  In the luminous body 20, the light emitted from the LED element 2 is reflected by the inclined surface 16 and is irradiated with high efficiency in a direction substantially perpendicular to the main surface 4. The conductive layer 8 is continuously provided from the main surface 4 to the slope 16 and is drawn outward from the main surface 4 to the slope 16. The conductive layer 8 is further connected to the electrode body 9. The electrode body 9 of the light emitting body 20 is connected to an external power source through, for example, a bonding wire, and the LED element 2 emits light by power supplied through the external power source. In the light emitting body 20, the bonding wire and the LED element 2 can be separated from each other, so that the LED element 2 can be prevented from being damaged in a wiring process such as a bonding process.

  The LED element 2 generates heat with light emission, and the conductive layer 8 and the base 6 thermally expand in response to the heat generation near the arrangement area of the LED element 2. For example, the substrate 6 made of ceramics and the conductive layer 8 made of, for example, a multilayer metal layer have different coefficients of thermal expansion, and the degree of thermal expansion due to light emission is different. In the light-emitting body 20, the conductive layer 8 is attached so as to cover the protruding portion 11 from the top surface 15 to the concave surface 17, and the adhesion strength between the base 6 and the conductive layer 8 is strong. Further, the conductive layer 8 is easily expanded and contracted in the direction perpendicular to the main surface 4. In the light emitting body 20, distortion at the joint surface between the base 6 and the conductive layer 8 is suppressed, and stress is dispersed in a direction perpendicular to the main surface 4. Moreover, in the light-emitting body 20, the base body 6 has the protruding portion 11, and the mechanical strength is relatively strong. For this reason, even if the thermal stress accompanying light emission / extinction of the LED element 2 is applied, the base 6 is relatively less likely to be cracked or cracked.

In the light emitting body 20, the conductive layer 8 is formed in a predetermined shape and a predetermined position with high accuracy, and a failure such as peeling of the conductive layer 8 due to light emission hardly occurs. The luminous body 20 has relatively high electrical performance and luminous efficiency, and relatively high operational reliability.
For example, the light emitter 20 may be manufactured as follows.

  First, the base 6 is produced. First, alumina powder and sintering aid powder are mixed, water is added, and wet pulverization is performed. After grinding, a slurry is prepared by adding and mixing polyvinyl alcohol or the like as an organic binder. The slurry is spray dried to produce granules. The granules are pressure-molded using a mold to form a formed body. The shape of this mold is designed so that the shape of the substrate is obtained after firing. For example, a recess is formed in the mold so as to become a convex portion after firing. The formed body is fired at 1500 to 1700 ° C., and the substrate 6 mainly composed of alumina is produced. Thereafter, if necessary, the surface of the substrate may be barrel-polished in order to remove burrs, and further washed and dried.

  Next, the conductive layer 8 is formed on the substrate 6. A paste containing Mo powder and Mn powder is applied so as to be placed on the top surface 15 of the protruding portion 11 of the produced base 6. In this paste application, the paste is defined and arranged with high accuracy over the entire top surface 15. The paste material spilled from the top surface 15 during this coating process is held by the concave surface 17 and is prevented from protruding to the side surface 13. Thereafter, the whole is heat-treated in a reducing atmosphere with the paste disposed. By heating, a first metal layer deposited on the substrate 6 is formed. Thereafter, a plating layer as a second metal layer is formed on the first metal layer. Plating is performed in the order of Ni plating and Au plating. The thickness of the Ni plating is, for example, 1 to 10 μm, and the thickness of the Au plating is, for example, 0.1 to 3 μm. The element mounting body 10 is manufactured in this way.

  Thereafter, the electrode body 9 is formed. The electrode body 9 disposed on the flat top surface 21 may be formed using a known printed wiring technique such as a screen printing method. For example, using a screen printing method, a paste containing Mo powder and Mn powder is applied in a predetermined shape, and heat treatment is performed in a reducing atmosphere to form a metallized layer having a predetermined shape. At this time, the paste passes over the convex portion (top portion) 11 a and is connected to the conductive layer 8. Thereafter, the electrode body 9 is formed by sequentially laminating Ni plating and Au plating on the metallized layer surface.

  Next, the LED element 2 is arranged on the created LED package 10. The LED 2 is disposed on the main surface 4 through the electrode 2. In the luminous body 2, an electrode (not shown) of the LED element 2 is disposed so as to face the conductive layer 8, and the electrode of the LED element 2 and the conductive layer 8 are bonded by flip chip bonding. For mounting the LED element 2, a method by which the LED element 2 and the conductive layer 8 can be electrically connected can be selected. For example, the mounting method may be a soldering method, wire bonding connected through a metal wire, or the like.

  Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention.

2 LED element 4 Plane part 6 Base 10 LED package 11 Projection part 15 Top surface 13 Side surface 15 Top surface 16 Slope 17 Concave surface 17a First inner surface 17b Second inner surface 18 Convex portion 19 Wall portion 20 Light emitter 21 Wall surface

Claims (8)

A functional element mounting body on which functional elements are mounted,
An insulating base having a planar portion and a protruding portion protruding from the planar portion;
A conductor layer that is electrically connected to the functional element and is deposited on the surface of the protruding portion;
The projecting portion has a top surface substantially parallel to the planar portion, and a concave surface is provided at a corner from the side surface continuous with the planar portion to the top surface,
The element mounting body, wherein the conductor layer is deposited from the top surface of the projecting portion to the concave surface.   The element mounting body according to claim 1, wherein the concave surface has a portion substantially parallel to the top surface. The base body includes a wall surface connected to the top surface and the concave surface of the projecting portion and substantially perpendicular to both the top surface and the concave surface;
The element mounting body according to claim 1, wherein the conductor layer is attached to the wall surface. The functional element is a light emitting element,
The base includes a slope that is continuous with the planar portion,
The element mounting body according to any one of claims 1 to 3, wherein the protruding portion and the conductor layer are continuously provided from the flat portion to the slope.   The element mounting body according to claim 1, wherein the base body contains ceramic as a main component.   6. The element mounting body according to claim 5, wherein the substrate is mainly composed of alumina. The element mounting body according to any one of claims 1 to 6,
A light emitting element disposed on the conductor layer of the element mounting body;
A light emitter characterized by comprising:   The light-emitting body according to claim 7, wherein the light-emitting element is flip-chip bonded onto the electrode.