JP2013183148A - Substrate for mounting semiconductor light-emitting element, method for manufacturing the same, and semiconductor light-emitting device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a substrate for mounting a semiconductor light-emitting element, in which sulfuration-resistant characteristics of a reflection layer and bonding strength are high, a method for manufacturing the substrate for mounting a semiconductor light-emitting element, and a semiconductor light-emitting device.SOLUTION: The substrate for mounting a semiconductor light-emitting element includes a base material and the reflection layer formed on at least a part of the surface on that side of the base material on which a semiconductor light-emitting element is to be mounted. In the reflection layer, a first opening for exposing a wire bonding region provided on a surface of the base material is formed.

Description

  The present invention relates to a semiconductor light emitting element mounting substrate, a method for manufacturing a semiconductor light emitting element mounting substrate, and a semiconductor light emitting device using the semiconductor light emitting element mounting substrate.

Generally, a semiconductor light emitting device represented by a light emitting diode (LED: Light Emitting Diode) and a laser diode (LD: Laser Diode), for example, on a copper base material or a metal resin composite base material as a semiconductor light emitting element mounting substrate, For example, an LED chip or an LD chip as a semiconductor light emitting element is mounted. The LED chip or LD chip and a part of the surface of the copper base material or metal resin composite base material are surrounded by an envelope made of, for example, a mold resin, and the inside of the envelope is filled with a transparent resin. Yes. The envelope forms an opening, and is formed so that the diameter of the opening increases as the distance from the copper base material or metal resin composite base material increases, that is, in an inverted truncated cone shape. The copper base material or metal resin composite base material and the LED chip or LD chip are electrically connected to each other by a bonding wire such as a gold wire, for example. That is, one end of the bonding wire is connected to a portion of the surface of the copper substrate or metal resin composite substrate that is exposed from the inside of the envelope, and the other end of the bonding wire is connected to the LED chip or the LD chip. The

  In the semiconductor light emitting device as described above, in order to efficiently emit the light emitted from the LED chip or LD chip to the outside, for example, an LED chip or LD chip of a copper base material or a metal resin composite base material is mounted. It is known to form a light reflection layer such as a silver plating layer having a high light reflectance on the side surface (see, for example, Patent Document 1). In such a semiconductor device, an LED chip or an LD chip is mounted on the light reflection layer. Thereby, the light radiated | emitted from the LED chip or LD chip | tip to the copper base material or the metal resin composite base material side is reflected by the light reflection layer, and is radiate | emitted outside through a transparent resin part. Therefore, the light emitted from the LED chip or the LD chip can be efficiently emitted to the outside.

  However, in the semiconductor light emitting device described in Patent Document 1 described above, since the envelope is made of a resin such as a mold resin, the resin transmits gas in the atmosphere such as hydrogen sulfide gas to the inside of the envelope. There was a case. For this reason, for example, hydrogen sulfide gas in the atmosphere that has passed through the inside of the envelope reacts with silver contained in the light reflecting layer, so that silver is sulfided and blackened in some cases. As a result, the reflectivity of the light reflection layer is drastically decreased, and the light emitted from the LED chip or the LD chip may not be efficiently emitted to the outside.

  Therefore, for example, a metal layer (light reflecting layer) containing at least one of silver, silver bismuth, and silver neodymium having high light reflectance is formed on the inclined surface of the frustoconical opening of the envelope, There has been proposed a semiconductor light emitting device in which a resin layer (primer) having a high gas shielding property is formed on at least a metal layer (light reflecting layer) (see, for example, Patent Document 2). Thereby, the light emitted from the LED chip or the LD chip can be efficiently emitted to the outside, and the blackening of the metal layer (light reflection layer) can be reduced. That is, the light emitted from the LED chip or the LD chip to the side (envelope side) is reflected by the metal layer (light reflecting layer) formed on the inclined surface of the envelope, so that the light is emitted. The light can be emitted efficiently. Then, by forming a resin layer having a high gas shielding property, it is possible to reduce the transmission of gas in the atmosphere such as hydrogen sulfide gas into the envelope, and to reduce the blackening of the light reflection layer.

JP 2007-149823 A JP 2010-10279 A

  However, the semiconductor light emitting device described in Patent Document 2 uses an acrylic resin as a constituent material of the resin layer. As described in Patent Document 2, the acrylic resin has the advantage of high gas shielding properties, while being inferior in heat resistance and light resistance, the acrylic resin is discolored (yellowed) by heat and light, In some cases, optical loss occurred. Therefore, the range of use of such a semiconductor light emitting device may be limited.

  Further, as another method for reducing the blackening of the light reflecting layer, for example, it is proposed to provide a protective layer such as a thin organic protective film for preventing sulfidation on the surface of the light reflecting layer containing silver or the like. However, before the bonding wires are connected, that is, before wire bonding, the semiconductor light emitting element mounting substrate is subjected to plasma cleaning or the like in order to stabilize the wire bonding property. Thereby, the protective layer formed on the light reflection layer may be deteriorated or peeled off, and there is a problem that the effect of preventing sulfidation may be reduced.

  Therefore, it is considered that an aluminum layer is formed as a reflective layer of the semiconductor light emitting element on the surface on which the semiconductor light emitting element such as a copper base material or a metal resin composite base material is mounted as the reflective layer of the semiconductor light emitting element. Yes. The aluminum layer has a high reflectance comparable to that of the light reflecting layer containing silver, and can suppress the sulfurization and blackening like the light reflecting layer containing silver.

  In such a semiconductor light emitting element mounting substrate, one end of the bonding wire is connected to the aluminum layer. The thickness of the aluminum layer is often thinner than the thickness of the light reflecting layer containing silver or the like, and does not have the strength necessary for wire bonding. For this reason, when wire bonding is performed, an aluminum oxide film is formed at the joint between the aluminum layer and the bonding wire, which may reduce the bonding strength. Accordingly, it is necessary to set and manage the wire bonding apparatus under such bonding conditions that the aluminum oxide film is sufficiently dispersed and does not remain on the bonding bonding surface (the surface of the aluminum layer). A slight natural oxide film is formed on the atmosphere side of the aluminum layer. For this reason, the thickness of the aluminum layer is formed to such a thickness that the presence of the natural oxide film does not become a problem. Thus, when the bonding wire is connected to the aluminum layer, in order to obtain bonding bonding strength, extremely strict bonding conditions are required as compared with the case where the bonding wire is connected to the light reflecting layer containing silver or the like. There is a problem that. Therefore, conventionally, by destroying the aluminum oxide film, room temperature metal bonding is realized and wire bonding is performed. When wire bonding is performed on the aluminum layer, an aluminum ribbon wire is preferably used and often connected by wedge bonding.

  Accordingly, the present invention provides a semiconductor light-emitting element mounting substrate, a semiconductor light-emitting element mounting substrate manufacturing method, and a semiconductor light-emitting device that solve the above-described problems and have a high anti-sulfurization property of the reflective layer and high bonding bonding strength. With the goal.

In order to solve the above problems, the present invention is configured as follows.
The first aspect of the present invention is:
A substrate;
A reflective layer formed on at least part of the surface of the substrate on which the semiconductor light emitting element is mounted, and
The reflective layer is provided with a semiconductor light emitting element mounting substrate in which a first opening for exposing a wire bonding region provided on the surface of the base is formed.

According to a second aspect of the invention,
A barrier layer is formed between the substrate and the reflective layer,
The semiconductor light emitting element according to the first aspect, wherein the barrier layer is formed with a second opening exposing the wire bonding region at a position corresponding to the first opening formed in the reflective layer. A mounting substrate is provided.

According to a third aspect of the invention,
Preparing a base material having a reflective layer formed on at least a part of the surface on which the semiconductor light emitting element is mounted;
Forming a resist layer on the reflective layer and exposing and developing the resist layer to form a predetermined resist pattern;
Etching the reflective layer using the resist pattern as a mask to form a first opening exposing a wire bonding region provided on the surface of the base material. A method is provided.

According to a fourth aspect of the invention,
Preparing a base material in which a barrier layer and a reflective layer are sequentially formed on at least a part of the surface on which the semiconductor light emitting element is mounted;
Forming a resist layer on the reflective layer and exposing and developing the resist layer to form a predetermined resist pattern;
The reflective layer is etched using the resist pattern as a mask to form a first opening in the reflective layer, and then the barrier layer is etched using the resist pattern and the reflective layer as a mask. Forming a second opening in the barrier layer to expose a wire bonding region provided on the surface, and a method for manufacturing a semiconductor light emitting element mounting substrate.

According to a fifth aspect of the present invention,
Preparing a substrate;
Forming a mask layer having a predetermined pattern on at least a part of the surface of the substrate on which the semiconductor light emitting element is mounted;
Forming a reflective layer by sputtering on at least a part of the surface of the substrate on which the semiconductor light emitting element is mounted that is not covered with the mask layer;
Forming a first opening in the reflective layer that exposes a wire bonding region provided on the surface of the base material by removing the mask layer. Provided.

According to a sixth aspect of the present invention,
Preparing a substrate;
Forming a mask layer having a predetermined pattern on at least a part of the surface of the substrate on which the semiconductor light emitting element is mounted;
A step of sequentially laminating the barrier layer and the reflective layer by sputtering on at least a part of the surface of the substrate on which the semiconductor light emitting element is mounted, which is not covered with the mask layer;
Forming a first opening and a second opening in the reflective layer and the barrier layer, respectively, exposing the wire bonding region provided on the surface of the substrate by removing the mask layer. A method for manufacturing a substrate for mounting a semiconductor light emitting element is provided.

According to a seventh aspect of the present invention,
A semiconductor light emitting device using either the semiconductor light emitting element mounting substrate according to the first or second aspect or the semiconductor light emitting element mounting substrate obtained by the manufacturing method according to any one of the third to sixth. Is provided.

  According to the present invention, it is possible to obtain a semiconductor light-emitting element mounting substrate, a semiconductor light-emitting element mounting substrate manufacturing method, and a semiconductor device, in which the reflective layer has high sulfuration resistance and high bonding bonding strength.

It is a schematic sectional drawing of the board | substrate for semiconductor light-emitting device mounting which concerns on one Embodiment of this invention. It is a schematic sectional drawing of the board | substrate for semiconductor light-emitting device mounting which concerns on the example of a change of one Embodiment of this invention. It is a schematic flowchart which shows the manufacturing process of the board | substrate for semiconductor light-emitting device mounting which concerns on one Embodiment of this invention. It is a schematic flowchart which shows the manufacturing process of the semiconductor light emitting element mounting substrate which concerns on other embodiment of this invention. It is a schematic sectional drawing of the semiconductor light-emitting device using the semiconductor light-emitting element mounting substrate shown in FIG. It is a schematic sectional drawing of the semiconductor light-emitting device using the semiconductor light-emitting element mounting substrate shown in FIG.

(One embodiment of the present invention)
A semiconductor light emitting device mounting substrate and a semiconductor light emitting device using the semiconductor light emitting device mounting substrate according to an embodiment of the present invention will be described below with reference to FIGS.

  As shown in FIGS. 1 and 2, a substrate 1 for mounting a semiconductor light emitting device (hereinafter also simply referred to as a substrate) according to this embodiment includes a base 2 and a side of the base 2 on which the semiconductor light emitting device is mounted. And a reflective layer 3 provided on at least a part of the surface.

  As the base material 2, a material composed of a metal member is preferably used. In addition, you may use the base material 2 which has a metal member. As the metal constituting the metal member, copper, copper alloy, or iron-based alloy is preferably used, but is not limited thereto. In particular, when the metal member is made of copper or a copper alloy, it is preferable from the viewpoint of electrical resistance and thermal resistance, and has the highest versatility. As the iron-based alloy, for example, an iron-nickel alloy such as 42 alloy, an iron-based frame material, or the like can be used. In consideration of mass production, it is preferable to use a hoop material made of copper as the base material 2, but a short sheet material or an individual material can also be used. Moreover, when the copper base material comprised from copper is used as the base material 2, there is no restriction | limiting in the thickness of a copper base material, thickness is selected in consideration of cost.

  A reflective layer 3 is provided on at least a part of the surface of the base 2 on which the semiconductor light emitting element is mounted. The reflective layer 3 reflects and emits light emitted from a semiconductor light emitting element described later. The reflective layer 3 may be formed in a region other than a region where an envelope 13 described later is formed. Specifically, the reflective layer 3 is formed on at least a part of the surface exposed from the bottom of the recess 14 formed in the envelope 13 to be described later, on the surface of the base 2 on which the semiconductor light emitting element is mounted. It only has to be done. Thereby, the reflective layer 3 is an envelope 13 which will be described later with light radiated from the semiconductor light emitting element mounted on the substrate 2 such as an LED chip or an LD chip to the base material 2 side (the reflective layer 3 side). The light can be efficiently reflected to the outside.

  The reflective layer 3 is an aluminum layer made of aluminum. Thereby, compared with the case where a silver layer or a silver alloy layer containing, for example, silver or a silver alloy is formed as the reflective layer 3, the anti-sulfurization characteristic of the reflective layer 3 is improved, the reflective layer 3 is blackened, and the reflectance is increased. Reduction can be suppressed. As a result, the semiconductor light emitting element mounting substrate 1 has high and stable reflection characteristics over a long period of time. Moreover, the aluminum used for the reflective layer 3 has a reflectance that is at least three times that of silver for ultraviolet rays, and has substantially the same reflectance for violet light, red light, and infrared rays as silver. Thus, by forming an aluminum layer as the reflective layer 3, a high reflectance can be ensured.

  The reflective layer 3 is formed, for example, by a vacuum vapor deposition method such as a batch process or a continuous process using a vacuum vapor deposition apparatus having a pressure reduction pressure adjustment function. As the vacuum vapor deposition apparatus, a resistance heating type barrel type apparatus is preferably used. The vacuum deposition apparatus may be, for example, an electron beam system or a plasma system. That is, as a vacuum deposition apparatus, for example, a carbon crucible as an evaporation source is used, and in the load lock system, a material that evaporates the material by irradiating the carbon crucible to form the reflective layer 3 is preferably used. A vacuum vapor deposition apparatus provided with a carbon crucible can perform stable vapor deposition continuously by appropriately optimizing a durable carbon crucible or the like. Moreover, you may use the continuous vapor deposition apparatus which can be vapor-deposited on a hoop material as a vacuum vapor deposition apparatus. The vacuum deposition apparatus can be selected as appropriate in consideration of the quality (film quality) of the reflective layer 3 and productivity. Note that the method for forming the reflective layer 3 is not limited to the vacuum vapor deposition method, and other factors such as ion plating (ion plating) method and sputtering method are considered in consideration of the quality and productivity of the reflective layer 3. A cladding method or the like can be used. The thickness of the reflective layer (aluminum layer) 3 is preferably 0.02 μm or more from the viewpoint of reflectivity, durability, etc., and more preferably 2 μm or less from the viewpoint of flatness.

  The reflective layer 3 is formed with a first opening 5 that exposes a wire bonding region 4 provided on the surface of the substrate 2. As a result, the bonding wire that connects the semiconductor light emitting element mounted on the base 2 and the semiconductor light emitting element mounting substrate 1 is connected to the base 2 via the first opening 5 formed in the reflective layer 3. It is connected to a wire bonding region 4 provided on the surface. That is, no junction with the bonding wire is formed on the reflective layer 3. As a result, it is possible to suppress the formation of an oxide film on the reflective layer 3 during wire bonding, and it is possible to suppress a decrease in bonding bond strength. In addition, since the bonding wire is connected to the wire bonding region 4 provided on the base material 2, the range of conditions for wire bonding is widened compared to the case of being connected to the reflective layer 3, and the assembly speed and yield are increased. improves.

  Note that wire bonding refers to, for example, a gold wire or a copper-based wire in order to electrically connect the electrode on the base material 2 (lead frame) side and the electrode on the semiconductor light emitting element mounted on the base material 2. It means connecting with a bonding wire such as an aluminum wire. Specifically, first, the tip of one end of the bonding wire is made spherical by discharge and connected to the electrode on the semiconductor light emitting element (1st bonding). Next, pressure bonding is performed in such a manner that the other end of the bonding wire is rubbed against the surface of the wire bonding region 4 at a predetermined position of the wire bonding region 4 (electrode on the substrate 2 side) provided on the surface of the substrate 2 ( 2nd bonding). As described above, in 1st bonding, connection by ball bonding is performed, and in 2nd bonding, connection by wedge bonding is often performed. In general, in view of positional accuracy and pressure bonding, the electrode on the semiconductor light emitting element side is often set to 1st bonding. The size of the region 4 where the bonding wire is bonded 2nd, that is, the opening diameter of the first opening 5 is preferably about 4 to 5 times the diameter of the bonding wire used.

  Moreover, as shown in FIG. 2, the base material 2 may be provided with, for example, a copper base material 2a containing copper or a copper alloy, and a silver layer containing silver or a silver alloy layer 2b containing a silver alloy. . That is, the silver layer or the silver alloy layer 2b may be formed on at least the surface of the copper base 2a on which the semiconductor light emitting element is mounted. In addition, even when the base material 2 in which the silver layer or the silver alloy layer 2b is formed on the copper base material 2a is used, the thickness of the reflective layer 3 formed on the base material 2 is 0.02 μm or more and 2 μm. It may be the following.

  The silver layer or the silver alloy layer 2b is formed by performing silver plating. A wet plating method is suitably used as the silver plating, and a silver cyanide plating bath is generally used as the wet plating method, but a non-cyanide bath or the like can also be used. Thereby, the base material 2 in which the silver layer or the silver alloy layer 2b is formed on the entire six surfaces of the copper base material 2a can be obtained at low cost. When performing silver plating, an organic brightener such as butynediol and saccharin, and a small amount of metal salt such as antimony, nickel, cobalt, tin, and selenium are added to the plating bath to form a silver layer or a silver alloy. The glossiness of the layer 2b can be further improved. Moreover, by adding a silver salt and adding a gold plating raw material such as potassium gold cyanide to the plating bath, silver alloy plating can be performed, and the silver alloy layer 2b can be formed. Similarly, silver alloy plating can also be performed by adding a compound salt such as platinum, palladium, rhodium, nickel, or indium into a plating bath to which a silver salt is added. Note that the silver layer or the silver alloy layer 2b having the desired quality of the present embodiment can also be formed by a dry plating method such as vacuum deposition.

  The thickness of the silver layer or the silver alloy layer 2b is preferably 1.0 μm or more and 5.0 μm or less, but can be appropriately changed depending on the semiconductor light emitting element to be mounted. In addition, when the silver layer or the silver alloy layer 2b is formed by the wet plating method, the thickness of the silver layer or the silver alloy layer 2b can be calculated by integrating the current values at the time of plating.

  In addition, a barrier layer 6 may be formed between the substrate 2 and the reflective layer 3. The barrier layer 6 contains at least one of titanium, nickel, chromium, cobalt, tantalum, niobium, vanadium, tungsten, and molybdenum. Thus, by forming the barrier layer 6, it can suppress that the base material 2 and the reflection layer 3 react. That is, it is possible to prevent a metal such as copper or oxygen contained in the base material 2 from diffusing into the reflective layer 3. The metal used for the barrier layer 6 is appropriately selected according to the purpose and application. As a method for forming the barrier layer 6, for example, a vacuum evaporation method, an electron beam evaporation method, a resistance heating evaporation method, an ion plating (ion plating) method, or a sputtering method in consideration of bonding characteristics and productivity. A cladding method or the like can be used.

  In the barrier layer 6, a second opening 7 that exposes the wire bonding region 4 provided on the surface of the substrate 2 is formed at a position corresponding to the first opening 5 provided in the reflective layer 3. . Thereby, the bonding wire for connecting the semiconductor light emitting element mounted on the substrate 2 and the semiconductor light emitting element mounting substrate 1 is formed in the first opening 5 and the barrier layer 6 formed in the reflective layer 3. In addition, it is connected to a wire bonding region 4 provided on the surface of the substrate 2 through the second opening 7. Accordingly, the range of conditions under which wire bonding can be performed is widened, and a decrease in bonding bonding strength can be suppressed.

[Method for Manufacturing Substrate for Semiconductor Light-Emitting Element Mounting]
Next, an embodiment of a method for manufacturing the semiconductor light emitting element mounting substrate 1 according to the present invention will be described. In the present embodiment, a manufacturing method for manufacturing the semiconductor light emitting element mounting substrate 1 shown in FIG. 2 will be described mainly with reference to FIG. FIG. 3 is a schematic flowchart showing the manufacturing process of the semiconductor light emitting element mounting substrate 1 according to the present embodiment.

  As shown in FIG. 3A, first, the base material 2 is prepared. In the base material 2, the barrier layer 6 and the reflective layer 3 are respectively formed in order from the base material 2 side on at least part of the surface of the base material 2 on the side where the semiconductor light emitting element is mounted. In the present embodiment, as the substrate 2, for example, a substrate including a copper substrate 2a containing copper and a silver alloy layer 2b containing silver or a silver alloy layer containing silver is used. That is, the base material 2 used in this embodiment has a silver layer containing silver or a silver alloy layer 2b containing a silver alloy formed on the surface of the copper base material 2a on the side where the semiconductor light emitting element is mounted.

  As a method for forming the reflective layer 3 on at least a part of the surface of the base 2 on which the semiconductor light emitting element is mounted, for example, in a device such as a vapor deposition apparatus for forming the reflective layer 3 described above, the base It is conceivable to provide a function of shielding areas other than the area where the reflective layer 3 on 2 is formed (for example, an area where an envelope 13 described later is provided). In addition, for example, after the reflective layer 3 is formed and formed on the entire surface of the substrate 2, for example, the reflective layer 3 formed in a region where an envelope 13 described later is provided is removed by etching or the like. There is. In addition, you may use methods other than these.

Next, a resist layer 8 is formed on the reflective layer 3 as shown in FIG. As the resist layer 8, for example, a dry resist film (A58 manufactured by Asahi Kasei E-Materials Co., Ltd.) can be used. Then, a dry resist film is placed on the reflective layer 3 formed on the substrate 2, and then thermocompression bonded at 120 ° C. using, for example, a roll laminator (GL835PRO manufactured by Aco Brands Japan Co., Ltd.). Thus, the resist layer 8 is formed on the reflective layer 3.

  The resist layer 8 is exposed and developed to form a predetermined resist pattern on the resist layer 8. In the present embodiment, a predetermined resist pattern (circular shape in the present embodiment) is formed on the resist layer 8 by performing exposure and development using a photomask having a predetermined mask pattern formed on the resist layer 8. Is forming. In addition, for example, a predetermined resist pattern may be formed on the resist layer 8 by a so-called direct drawing method using a laser beam or the like.

  Then, as shown in FIG. 3C, the reflective layer 3 is etched using a predetermined resist pattern formed on the resist layer 8 as a mask, on the surface of the base material 2 (in this embodiment, a silver layer or a silver layer). A first opening 5 exposing the wire bonding region 4 provided on the surface of the alloy layer 2b is formed.

  Specifically, the resist layer 8 and the reflective layer 3 are exposed with ultraviolet g rays using an exposure apparatus (for example, EMA-400 manufactured by Union Optics Co., Ltd.). Thereafter, development and water washing are performed with a 3% by weight aqueous solution of sodium hydroxide. When washing with water, the exposed resist layer 8 and the reflective layer 3 (aluminum) are dissolved and removed with sodium hydroxide to form a predetermined resist pattern and the first opening 5. Thus, the partial etching of the reflective layer 3 can be performed during the normal development time of the resist layer 8, and a resist pattern can also be formed. In this embodiment, it is sufficient to perform the immersion for 90 seconds in the developer at room temperature, but for the sake of safety, additional immersion was performed for 5 seconds. Industrially, an apparatus that performs continuous development often employs a method in which a developer is sprayed in a shower, and it is necessary to determine the development time in accordance with the conditions according to the apparatus. In this embodiment, a predetermined resist pattern is formed on the resist layer 8 and at the same time, the reflective layer 3 is etched using the resist pattern formed on the resist layer 8 as a mask to form the first opening 5. However, the present invention is not limited to this. That is, the formation of the resist pattern on the resist layer 8 and the etching of the reflective layer 3 do not have to be performed simultaneously, and may be performed separately. Further, when the reflective layer 3 is provided on the entire surface of the base material 2, the reflective layer 3 formed in a region where an envelope 13 to be described later is provided is etched simultaneously with the formation of the first opening 5. It may be removed.

  Thereafter, as shown in FIG. 3D, the wire bonding region provided on the surface of the base material 2 by etching the barrier layer 6 using the resist pattern formed in the resist layer 8 and the reflective layer 3 as a mask. A second opening 7 is formed to expose 4.

  Specifically, the substrate 2 on which the barrier layer 6 is formed is immersed for 10 seconds in a mixed solution (diluted solution) containing 10% by weight of a mixture in which hydrofluoric acid: ammonium fluoride is mixed at a ratio of 1: 6. As a result, the barrier layer 6 was etched to form the second opening 7. The etching of the barrier layer 6 is preferably performed by immersing in a hydrofluoric acid-based etching solution, but is not limited to this. That is, the etching rate may be adjusted by appropriately changing the concentration and composition of the etching solution in consideration of the thickness and temperature of the barrier layer 6.

  Thereafter, as shown in FIG. 3E, the resist layer 8 is peeled off. Specifically, after exposing the wire bonding region 4 provided on the surface of the substrate 2, the resist layer 8 was peeled by dipping in a release agent. As the release agent, for example, PK-SFR8130 manufactured by Parker Corporation is used. And the semiconductor light emitting element mounting substrate 1 which concerns on this embodiment is obtained, and the manufacturing process is complete | finished.

  Note that the manufacturing method according to this embodiment can also be applied to manufacturing the semiconductor light emitting element mounting substrate 1 in which the barrier layer 6 is not formed between the base material 2 and the reflective layer 3. That is, first, a base material 2 having a reflective layer 3 formed on at least a part of a surface on which a semiconductor light emitting element is mounted is prepared. Next, a resist layer 8 is formed on the reflective layer 3, and the resist layer 8 is exposed and developed to form a predetermined resist pattern. Then, the reflective layer 3 is etched using the resist pattern as a mask, thereby forming a first opening 5 that exposes the wire bonding region 4 provided on the surface of the substrate 2. Thereafter, the resist layer 8 is peeled off to obtain the semiconductor light emitting element mounting substrate 1 on which the barrier layer 6 is not formed.

  The manufacturing method of the semiconductor light emitting element mounting substrate 1 according to the present invention is not limited to the above manufacturing method. Next, another embodiment of the method for manufacturing the semiconductor light emitting element mounting substrate 1 according to the present invention will be described mainly with reference to FIG. FIG. 4 is a schematic flowchart showing the manufacturing process of the semiconductor light emitting element mounting substrate 1 according to the present embodiment.

  The manufacturing method according to this embodiment is different from the manufacturing method shown in FIG. 3 described above in that after the mask layer 9 is formed on the substrate 2, the barrier layer 6 and the reflective layer 3 are sequentially formed by sputtering. By removing the layer 9, the first opening 5 is formed in the reflective layer 3 and the second opening 7 is formed in the barrier layer 6 at the same time.

  In this embodiment, as shown to Fig.4 (a), the base material 2 is prepared first. In this embodiment, the base material 2 provided with the copper base material 2a containing copper and the silver alloy layer 2b containing the silver layer or silver alloy containing silver is prepared as the base material 2, for example. The silver layer or silver alloy layer 2b is provided on the surface of the copper substrate 2a on which the semiconductor light emitting element is mounted.

  Next, as shown in FIG. 4B, a mask layer 9 having a predetermined pattern is formed on at least a part of the surface of the base 2 on which the semiconductor light emitting element is mounted. As the mask layer 9, for example, a polyimide resin film or a metal member containing metal can be used. In the case of the present embodiment, since the polymer mask layer 9 is already disposed when the reflective layer 3 is formed, impurities such as carbon are present in the reflective layer 3 in the formation of the reflective layer 3. It may be mixed. Therefore, it is more preferable to dispose the mask layer 9 made of a metal member for the purpose of suppressing the entry of impurities into the film quality of the reflective layer 3.

Then, as shown in FIG. 4C, the barrier layer 6 is formed by sputtering on at least a part of the surface of the substrate 2 on the side where the semiconductor light emitting element is mounted that is not covered with the mask layer 9. Thereafter, as shown in FIG. 4D, the reflective layer 3 is formed on the barrier layer 6 not covered with the mask layer 9 by sputtering, and the reflective layer 3 is laminated on the barrier layer 6.

  Thereafter, as shown in FIG. 4E, the mask layer 9 is removed. As a result, the first opening 5 is formed in the reflective layer 3, and the second opening 7 is formed in the barrier layer 6. The first opening 5 and the second opening 7 are openings that expose the wire bonding region 4 provided on the surface of the substrate 2 (on the surface of the silver layer or the silver alloy layer 2b in this embodiment). And the semiconductor light emitting element mounting substrate 1 which concerns on this embodiment is obtained, and the manufacturing process is complete | finished.

  Note that the manufacturing method according to this embodiment can also be applied to manufacturing the semiconductor light emitting element mounting substrate 1 in which the barrier layer 6 is not formed between the base material 2 and the reflective layer 3. That is, first, the base material 2 is prepared. Next, a mask layer 9 having a predetermined pattern is formed on at least a part of the surface of the base 2 on which the semiconductor light emitting element 1 is mounted. Then, the reflective layer 3 is formed by sputtering on at least a part of the surface of the substrate 2 on the side where the semiconductor light emitting element is mounted that is not covered with the mask layer 9. Then, the reflective layer 3 is formed by removing the mask layer 9 to expose the first opening 5 that exposes the wire bonding region 4 provided on the surface of the substrate 2. Thereby, even if it is the manufacturing method which concerns on this embodiment, the board | substrate 1 for semiconductor light-emitting device mounting in which the barrier layer 6 is not formed is obtained.

[Semiconductor light emitting device]
Next, a semiconductor light emitting device using the semiconductor light emitting element mounting substrate 1 described above will be described. FIG. 5 is a schematic cross-sectional view of a semiconductor light emitting device using the semiconductor light emitting element mounting substrate 1 shown in FIG. FIG. 6 is a schematic cross-sectional view of a semiconductor light emitting device using the semiconductor light emitting element mounting substrate 1 shown in FIG. The difference between the semiconductor light emitting device shown in FIG. 5 and the semiconductor light emitting device shown in FIG. 6 is that the semiconductor light emitting device in which the barrier layer 6 is formed between the base material 2 and the reflective layer 3 as shown in FIG. Whether the element mounting substrate 1 is used or the semiconductor light emitting element mounting substrate 1 in which the barrier layer 6 is not formed as shown in FIG. 5 is used. Therefore, hereinafter, a semiconductor light emitting device using the semiconductor light emitting element mounting substrate 1 on which the barrier layer 6 shown in FIG. 6 is formed will be mainly described, and description of the semiconductor light emitting device shown in FIG. 5 will be omitted.

  As shown in FIG. 6, in the semiconductor light emitting device 10, two semiconductor light emitting element mounting substrates 1 </ b> A and 1 </ b> B are arranged close to each other on substantially the same surface. Then, the semiconductor light emitting element 11 is mounted on the reflective layer 3 of the one substrate 2, and the first opening that exposes the wire bonding region 4 to the reflective layer 3 and the barrier layer 6 of the other substrate 2. 5 and the second opening 7 are respectively formed so as to expose the wire bonding region 4. As the semiconductor light emitting element 11, for example, an LED chip such as a GaAs-Si-LED, an AlGaAs-LED, a GaP-LED, an AlGaInP-LED, an InGaN-LED, or an LD chip is used. Then, the semiconductor light emitting element 11 is mounted on the reflective layer 3 formed on the base material 2 via, for example, a conductive paste. Then, the bonding wire 12 is bonded to the surface of the base material 2 (wire bonding region 4) exposed from the first opening 5 and the second opening 7 formed in the reflective layer 3 and the barrier layer 6, and the semiconductor light emitting element 11. Is connected.

An envelope 13 is provided so as to surround the reflective layer 3 formed on the substrate 2 and the semiconductor light emitting element 11. The envelope 13 is made of a resin such as a mold resin. Then, at least a part of the back surface of the semiconductor light emitting element mounting substrates 1A and 1B is covered with a resin constituting the envelope 13. The envelope 13 is formed with a recess 14 whose diameter increases as the distance from the base material 2 increases. That is, the recessed part 14 is formed in the shape of an inverted truncated cone opened in a divergent shape, and the side surface of the recessed part 14 is formed in an inclined surface. In addition, the side surface of the recessed part 14 may not be an inclined surface, for example, may be a vertical surface. Recess 14 of envelope 13
A reflective layer (not shown) containing aluminum, for example, may be formed on the side surface constituting the film. Thereby, the light radiated | emitted from the semiconductor light-emitting element 11 can be radiate | emitted to the exterior more efficiently.

  The semiconductor light emitting element 11 is sealed by filling the inside of the recess 14 of the envelope 13 with a transparent resin (light transmissive resin) 15. As the transparent resin 15, for example, a transparent epoxy resin or the like can be used.

  Note that the transparent resin 15 may be mixed with a phosphor material such as yttrium aluminum garnet (YAG). Thereby, the wavelength of the light emitted from the semiconductor light emitting element 11 can be converted. That is, for example, when a GaN LED chip having a wavelength of 460 nm is used as the semiconductor light emitting element 11, a pseudo white LED device can be obtained as the semiconductor light emitting device 10.

  In the semiconductor light emitting device 10 according to this embodiment, the reflective layer 3 is exposed from the bottom of the recess 14 of the envelope 13. Therefore, the light emitted from the semiconductor light emitting element 11 is reflected by the reflective layer 3 toward the opening side of the recess 14 (envelope 13). Then, the light reflected by the reflective layer 3 passes through the transparent resin 15 filled in the recess 14 and is emitted to the outside of the semiconductor light emitting device 10. As a result, the amount of light emitted from the semiconductor light emitting device 10 to the outside can be increased. That is, the light emitted from the semiconductor light emitting element 11 can be efficiently emitted to the outside of the semiconductor light emitting device 10. The reflective layer 3 contains aluminum. As a result, the semiconductor light emitting device 10 has high and stable reflection characteristics over a long period of time.

(Effect according to this embodiment)
According to the present embodiment, one or more effects shown below are produced.

(A) According to this embodiment, the substrate 1 for mounting a semiconductor light emitting element includes the base material 2, and the reflective layer 3 is provided on at least a part of the surface of the base material 2 on the side where the semiconductor light emitting element 11 is mounted. Is formed. The reflective layer 3 has a first opening 5 that exposes the surface of the substrate 2.

  As a result, a decrease in bonding bond strength can be suppressed, and the range of bonding conditions can be expanded. That is, one end of the bonding wire 12 is connected to a wire bonding region 4 provided on the surface of the substrate 2 through a first opening 5 formed in the reflective layer 3. 12 is not formed. In addition, since the bonding wire 12 is connected to the wire bonding region 4 provided on the base material 2, the range of conditions for wire bonding is widened compared to the case where it is connected to the reflective layer 3, and the assembly speed and yield are increased. Will improve.

  Moreover, by forming an aluminum layer containing aluminum as the reflective layer 3, it is possible to improve the sulfidation resistance. That is, it can suppress that the reflective layer 3 is blackened and a reflectance falls compared with the case where the silver layer and silver alloy layer 2b containing silver and a silver alloy are formed as the reflective layer 3, for example. As a result, the semiconductor light emitting element mounting substrate 1 has high and stable reflection characteristics over a long period of time.

(B) According to this embodiment, the barrier layer 6 is formed between the base material 2 and the reflective layer 3. The barrier layer 6 has a second opening 7 that exposes the wire bonding region 4 at a position corresponding to the first opening 5 formed in the reflective layer 3. Thereby, it can suppress that the base material 2 and the reflection layer 3 react. Moreover, the conditions for wire bonding are widened.

(Other embodiments of the present invention)
As mentioned above, although one Embodiment of this invention was described concretely, this invention is not limited to the above-mentioned embodiment, In the range which does not deviate from the summary, it can change suitably.

In the embodiment described above, the case where a plate material made of copper, a copper alloy, or an iron-based alloy is used as the base material 2 has been described. In addition, for example, as the base material 2, for example, a composite material in which a metal such as copper or a copper alloy and a plate material (not shown) using an organic material or an inorganic material are combined may be used. That is, for example, a copper-clad plate or a laminate thereof obtained by pasting copper such as copper wiring on a hard, thin, and flexible resin plate using an organic material may be used. As the organic material, for example, an epoxy resin, a polyimide resin, an acrylic resin, a polyester resin, a polystyrene resin, or the like can be used. Specifically, for example, a glass epoxy substrate or a glass cloth substrate resin plate can be used. As the inorganic material, for example, silicon, a III-V group compound semiconductor such as GaAs or InP, quartz glass, or the like can be used. In addition, the board | plate material using an organic material or an inorganic material is opposite to the surface on the opposite side to the surface by which the semiconductor light emitting element 11 is mounted of the metal part of the base material 2, ie, the surface where the reflective layer 3 is provided. It is formed on the side surface.

  Moreover, in embodiment mentioned above, the case where the base material 2 was comprised with a copper base material, and the case provided with the copper base material 2a and the silver alloy layer 2b containing the silver layer or silver alloy containing silver were demonstrated. . In addition, for example, the base material 2 may include a copper base material 2a containing copper or a copper alloy, and a metal layer. That is, a metal layer may be formed on at least the surface of the copper substrate 2a on which the semiconductor light emitting element is mounted.

The metal layer is formed including a metal having a high melting point. Specifically, the metal layer is formed including at least one of palladium, gold, tin, nickel, copper-tin alloy, copper-nickel alloy, and iron-nickel alloy. Compared with copper, palladium has an advantage of preventing discoloration (antioxidation effect) due to oxidation of copper, being easily compatible with tin used in solder, and ensuring solder wettability. Gold has the advantage of improving solder wettability. Tin has the advantage that it is easy to solder and is inexpensive, but it may have the disadvantage of being easily oxidized. Nickel is highly effective in preventing discoloration due to oxidation of copper, and has the advantage that the handling characteristics of the semiconductor light emitting element mounting substrate 1 are improved. Further, for example, copper contained in the base material 2 such as the copper base material 2a can be prevented from diffusing to the reflective layer 3 side. That is, the copper diffusion barrier property is improved. The copper-tin alloy has an advantage that it has a higher antioxidation effect than copper, and is easier to get used to tin than tin or copper. The copper-nickel alloy has the advantage of being easily compatible with tin compared to nickel. An iron-nickel alloy has an advantage that it has a low coefficient of thermal expansion and good bondability with an inorganic material. Based on these points, for example, depending on the use conditions / manufacturing conditions such as ease of plating, cost, solder characteristics, copper diffusion barrier properties, etc., the material that forms one or more metal layers optimal as a metal layer is appropriately selected. Selected.

  For example, the base material 2 may include a copper base material 2a containing copper or a copper alloy, a nickel layer, and a palladium layer. That is, a nickel layer may be formed on at least a part of the surface of the copper base 2a on which the semiconductor light emitting element is mounted, and a palladium layer may be formed on a part of the surface of the nickel layer.

  The nickel layer and the palladium layer can be formed by a wet plating method such as electroplating. Thereby, it is often possible to form a nickel layer and a palladium layer on the entire six surfaces of the substrate 2 at low cost. The nickel layer and the palladium layer having the desired quality of the present invention can also be formed by a dry plating method such as vacuum deposition.

  The thickness of the nickel layer is preferably 0.4 μm or more and 1.5 μm or less, and the thickness of the palladium layer is preferably 0.01 μm or more and 0.2 μm or less. The thicknesses of the nickel layer and the palladium layer are appropriately adjusted depending on the soldering conditions. In addition, when the nickel layer and the palladium layer are formed by a wet plating method, the thickness (film thickness) of the nickel layer and the palladium layer can be calculated by integrating current values at the time of plating.

  As described above, by forming a nickel layer on the surface of the base material 2, discoloration due to copper oxidation of the copper base material 2 a can be suppressed, and handling characteristics of the semiconductor light emitting element mounting substrate 1 are improved. In addition, it is possible to prevent the copper contained in the copper base 2a from diffusing to the reflective layer 3 side.

  Also, a palladium layer is formed on the surface of the nickel layer, and the outermost surface layer of the substrate 2 is a palladium layer, whereby the second opening formed in the first opening 5 and the barrier layer 6 formed in the reflective layer 3. The surface of the wire bonding region 4 exposed from the opening 7 becomes a palladium layer. Therefore, at the time of wire bonding, one end of the bonding wire is connected to the wire bonding region 4, that is, the surface of the palladium layer. Palladium is a stable metal that is difficult to oxidize, so that the bonding strength can be further improved.

  Further, for example, a gold flash plating layer may be formed on the outermost surface of the substrate 2 on the side where the semiconductor light emitting element is mounted. The gold flash plating layer is formed by, for example, a wet plating method. The thickness of the gold flash plating layer can be appropriately changed according to the semiconductor light emitting element to be mounted, but is preferably 0.1 μm or less. In addition, when a gold flash plating layer is formed by a wet plating method, the thickness of the gold flash plating layer can be calculated by integrating current values during plating.

  In the above-described embodiment, the silver layer or the silver alloy layer 2b, the metal layer, the nickel layer and the palladium layer, and the gold flash plating layer respectively form the semiconductor light emitting element 11 of the copper base material 2a constituting the base material 2, for example. Although it formed on the surface of the mounting side, it is not limited to this. That is, you may form on both surfaces of the copper base material 2a, and may form only on the surface on the opposite side to the side which mounts the semiconductor light-emitting element 11 of the copper base material 2a.

  Moreover, you may form the silver layer or the silver alloy layer 2b on the surface of the metal layer formed on the copper base material 2a which comprises the base material 2, for example including copper, or the nickel layer and the palladium layer. Then, the reflective layer 3 is formed on the silver layer or the silver alloy layer 2b.

  In the above embodiment, the first opening 5 formed in the reflective layer 3 and the second opening 7 formed in the barrier layer 6 are formed in a circular shape, but the present invention is not limited to this. For example, the first opening 5 and the second opening 7 may be rectangular or the like, and if the wire bonding region 4 provided on the surface of the substrate 2 can be exposed, the first opening 5 The shape of 5 and the shape of the second opening 7 may be different.

In the above-described embodiment, the vertical element in which electrodes are formed on the front surface and the back surface of the semiconductor light emitting element 11 is used as the semiconductor light emitting element 11, but the present invention is not limited to this. For example, a lateral element such as a planar LED (for example, GaN-based) that forms a pair of electrodes on the same surface may be used. In the case of a lateral element such as a planar structure, a method of electrically connecting the cathode and the anode with a bonding wire 12 with the electrode surface facing the surface side (opposite side of the substrate 2), and the electrode surface Any method of direct connection of the cathode and the anode (so-called flip chip mounting method) may be used facing downward (base material 2 side). When a vertical element is used as the semiconductor light emitting element 11, one or more power supply terminals may be used for connection between the bonding wire 12 and the surface electrode, and a plurality of power supply terminals connected to the surface electrode may be provided. Wire bonding connection may be used. When a plurality of power supply terminals are used, the layout of wiring between light-emitting devices may be facilitated when driving with a large current, which is used properly.

  In the above-described embodiment, as shown in FIGS. 5 and 6, the case where the two semiconductor light emitting element mounting substrates 1A and 1B used in the semiconductor light emitting device 10 have the same layer configuration has been described. It is not limited to. That is, for example, one substrate for semiconductor light emitting element mounting 1A uses a base material 2 having a copper base 2a and a silver layer or a silver alloy layer 2b, and another substrate for semiconductor light emitting element mounting 1B. The base material 2 provided with the copper base material 2a, the nickel layer, and the palladium layer, and the nickel layer and the palladium layer formed in order from the copper base material 2a side may be used. That is, the two substrates for semiconductor light emitting elements 1A and 1B used in the semiconductor light emitting device 10 may use the base material 2 of the above-described embodiment having different layer configurations.

  In the above-described embodiment, as shown in FIGS. 5 and 6, at least a part of the bottom surface of the semiconductor light emitting element mounting substrates 1 </ b> A and 1 </ b> B used in the semiconductor light emitting device 10 is a resin constituting the envelope 13. However, the present invention is not limited to this. For example, the entire bottom surface of the semiconductor light emitting element mounting substrates 1 </ b> A and 1 </ b> B may be covered with a resin constituting the envelope 13. Further, for example, the entire bottom surface of the semiconductor light emitting element mounting substrates 1A and 1B may be exposed. That is, the entire bottom surface of the semiconductor light emitting element mounting substrates 1 </ b> A and 1 </ b> B may not be covered with the resin constituting the envelope 13. When the entire bottom surfaces of the semiconductor light emitting element mounting substrates 1A and 1B are exposed, for example, a metal heat sink or the like is attached to the bottom surfaces of the semiconductor light emitting element mounting substrates 1A and 1B by soldering or the like. It is good to connect. Thereby, the heat dissipation of the semiconductor light emitting device 10 is improved and the light output can be increased.

  In the above-described embodiment, the case where the 1st bonding is performed by ball bonding and the 2nd bonding is performed by wedge bonding has been described. However, the present invention is not limited to this. That is, for example, 1st bonding may be performed by wedge bonding, and 2nd bonding may be performed by ball bonding. Furthermore, the bonding wire 12 and the electrode of the substrate 2 (lead frame) may be connected by 1st bonding, or the bonding wire 12 and the electrode on the semiconductor light emitting element 11 may be connected by 2nd bonding.

  In these embodiments, the same effects as those of the above-described embodiments are obtained.

  Next, examples of the present invention will be described, but the present invention is not limited thereto.

(Example)
In the examples, first, a copper substrate of a copper strip including a copper alloy (C-194) having a length of 100 m, a width of 50 mm, and a thickness of 0.2 mm was prepared. Then, a nickel layer having a thickness of 0.5 μm and a palladium layer having a thickness of 0.05 μm are wet on the surface of the copper substrate on which the semiconductor light emitting element 11 is mounted in order from the copper substrate side. A base material 2 formed by a plating method was prepared. In addition, the thickness of the nickel layer and the palladium layer was calculated based on the integrated value of the current value at the time of plating.

Next, a resistance heating type barrel-type vacuum vapor deposition apparatus is used to form an aluminum layer on the surface of the substrate 2 on which the semiconductor light emitting element 11 is mounted, that is, on the surface of the palladium layer in this embodiment. A reflective layer 3 was formed. Specifically, first, the above-described base material 2 was cut into a short material having a width of 50 mm and a length of 150 mm. And 16 cut | disconnected base materials 2 were arranged radially on the umbrella-shaped jig | tool with a radius of 300 mm, and this set 3 units | sets were arrange | positioned to the barrel. And the output of the resistance heating source was set to 1 kW, and exhausted until the degree of vacuum was 8 × 10 ⁻⁴ Pa. Thereby, the reflective layer 3 composed of an aluminum layer having a thickness of 0.05 μm was formed on the surface of the substrate 2.

  After forming the reflective layer 3 on the surface of the substrate 2 on which the semiconductor light emitting element 11 is mounted, the reflective layer 3 is etched to expose the wire bonding region 4 provided on the surface of the substrate 2. Are formed in the reflective layer 3. Specifically, first, after a dry resist film (A58 manufactured by Asahi Kasei E-Materials Co., Ltd.) is placed on the reflective layer 3, for example, a roll laminator (GL835PRO manufactured by Aco Brands Japan Co., Ltd.) is used. The resist layer 8 is formed on the reflective layer 3 by thermocompression bonding at 120 ° C. Thereafter, the resist layer 8 is exposed and developed to form a predetermined resist pattern on the resist layer 8. Then, the resist layer 8 and the reflective layer 3 are exposed with ultraviolet g rays using an exposure apparatus (for example, EMA-400 manufactured by Union Optics Co., Ltd.). Thereafter, development and water washing are performed with a 3% by weight aqueous solution of sodium hydroxide. When washing with water, the exposed portions of the resist layer 8 and the reflective layer 3 (aluminum) are dissolved and removed with sodium hydroxide, and a first opening 5 having a predetermined shape is formed in the reflective layer 3. In this example, since the bonding wire 12 having a wire diameter of 25 μm was used, the shape (opening diameter) of the first opening 5 was set to 100 μm, which is four times the wire diameter of the bonding wire 12.

Thereafter, the position of the first opening 5 formed on the reflective layer 3 is aligned, and a stamping is performed on the pattern of the LED chip (SMD: surface mount type) as the semiconductor light emitting element 11, and the semiconductor light emitting element mounting substrate 1 was produced.

(Comparative example)
In the comparative example, the first opening 5 that exposes the wire bonding region 4 provided on the surface of the substrate 2 was not formed in the reflective layer 3. Other than that, a substrate for mounting a semiconductor light emitting element was fabricated in the same manner as in the above-described example.

(Evaluation of reflectivity and anti-sulfur properties)
About the above-mentioned Example and comparative example, the reflectance and the sulfidation resistance were confirmed as follows.

  First, the reflectance is evaluated. The initial reflectivity of the reflective layer 3 of the example and the comparative example was as good as 91% at a wavelength of 460 nm. In addition, the initial reflectance in this case is a reflectance compared with the case where the reflectance of barium sulfate at a wavelength of 460 nm is 100%.

Next, the resistance to sulfuration is evaluated. For the anti-sulfurization property, a test based on the corrosion resistance test method of JIS H8502 plating was performed. That is, 3 ppm of H ₂ S (hydrogen sulfide) was sprayed for 96 hours at an ambient temperature of 40 ° C. and a humidity of 80% to the samples of the semiconductor light emitting element mounting substrate prepared in the above examples and comparative examples. Then, about each sample of an Example and a comparative example, when the change of the reflectance in wavelength 460nm was measured, the reflectance ratio was 98%. The reflectance ratio in this case is a ratio compared to the case where the initial reflectance of each sample is 100%. That is, when an aluminum layer is formed as the reflective layer 3, the reflectance ratio after spraying H2S for 96 hours is 98% with respect to the initial reflectance, which is almost unchanged from the initial reflectance, and can maintain a high level. It was found to have a high resistance to sulfuration.

(Evaluation of bonding strength)
Next, about the above-mentioned Example and comparative example, the bonding joint strength was confirmed as follows.

In the example, first, argon plasma cleaning was performed to wire bond the wire bonding region 4 exposed from the first opening 5 formed in the reflective layer 3. Then, a GaAlInP-LED (emission wavelength 640 nm) chip as the semiconductor light emitting element 11 is placed on a portion of the reflective layer 3 where the first opening 5 is not formed, and a silver paste (made by Harima Kasei Co., Ltd.) Die bonding was performed using a functional silver paste (product number ST) (curing conditions: 170 ° C., 3 hours). Thereafter, wire bonding was performed using a gold wire (M3 25 μmφ manufactured by Tanaka Kikinzoku Co., Ltd.) as the bonding wire 12 and a wire bonder (4522 manufactured by K & S) as the bonding apparatus. A capillary having a tip diameter of 160 μm was used. That is, first, one end of the bonding wire 12 was connected to the electrode on the semiconductor light emitting element 11 (1st bonding). Thereafter, the other end of the bonding wire 12 was connected to the wire bonding region 4 provided on the surface of the substrate 2 (2nd bonding).

  In the comparative example, first, the surface of the reflective layer 3 was cleaned with argon plasma in order to perform wire bonding. Then, one end of the bonding wire 12 was connected to the electrode on the semiconductor light emitting element 11 (1st bonding). Thereafter, the other end of the bonding wire 12 was connected to the reflective layer 3 formed on the substrate 2 (2nd bonding). Other than that, wire bonding was performed in the same manner as in the above-described example.

  The bonding strength of the semiconductor light emitting element mounting substrate thus fabricated was evaluated. Table 1 shows the results of the evaluation test of the bonding strength of the examples and comparative examples. Bonding bonding strength was evaluated by a wire pull test (type 4000 manufactured by Dage). Specifically, 20 wire bondings were performed for each of the example and the comparative example. Then, 10 wire pull tests were carried out for the 1st bonding, and 10 pieces were carried out for the 2nd bonding, and the average value of each was measured to obtain the bonding bond strength. In addition, the measurement position was set to be within 20% of the distance between the joints in the vicinity of each of the first bonding joint and the 2nd bonding joint. And bond bonding strength set as (circle) the thing obtained 30 mN or more by the wire pull test, and made less than 30 mN x.

  As shown in Table 1, as for the 1st bonding joint strength, sufficient bonding joint strength of 50 mN or more was obtained in both Examples and Comparative Examples. The 2nd bonding bonding strength of the example was a stable high bonding bonding strength of 40 mN. On the other hand, the bonding strength of the 2nd bonding of the comparative example was about 10 mN, and the strength was not obtained so much.

  As described above and as shown in Table 1, it was found that the semiconductor light-emitting element mounting substrates 1 of Examples and Comparative Examples have high reflectivity and high resistance to sulfuration. Further, it was found that the semiconductor light-emitting element mounting substrate 1 of the example had high both the first bonding bonding strength and the second bonding bonding strength. On the other hand, it was found that in the comparative example in which the wire bonding was performed on the reflective layer 3, the 2nd bonding strength was lowered.

DESCRIPTION OF SYMBOLS 1 Substrate for semiconductor light emitting element mounting 2 Base material 3 Reflective layer 4 Wire bonding area 5 First opening 6 Barrier layer 7 Second opening 8 Resist layer 9 Mask layer 10 Semiconductor light emitting device 11 Semiconductor light emitting element 12 Bonding wire 13 14 Recess 15 Transparent resin

Claims (7)

A substrate;
A reflective layer formed on at least part of the surface of the substrate on which the semiconductor light emitting element is mounted, and
A substrate for mounting a semiconductor light emitting element, wherein the reflective layer is formed with a first opening exposing a wire bonding region provided on the surface of the base material. A barrier layer is formed between the substrate and the reflective layer,
The second opening for exposing the wire bonding region is formed in the barrier layer at a position corresponding to the first opening formed in the reflective layer. A substrate for mounting a semiconductor light emitting device. Preparing a base material having a reflective layer formed on at least a part of the surface on which the semiconductor light emitting element is mounted;
Forming a resist layer on the reflective layer and exposing and developing the resist layer to form a predetermined resist pattern;
Etching the reflective layer using the resist pattern as a mask to form a first opening exposing a wire bonding region provided on the surface of the substrate. Manufacturing method of mounting substrate. Preparing a base material in which a barrier layer and a reflective layer are sequentially formed on at least a part of the surface on which the semiconductor light emitting element is mounted;
Forming a resist layer on the reflective layer and exposing and developing the resist layer to form a predetermined resist pattern;
The reflective layer is etched using the resist pattern as a mask to form a first opening in the reflective layer, and then the barrier layer is etched using the resist pattern and the reflective layer as a mask. Forming a second opening in the barrier layer to expose a wire bonding region provided on the surface. A method of manufacturing a substrate for mounting a semiconductor light emitting element, comprising: Preparing a substrate;
Forming a mask layer having a predetermined pattern on at least a part of the surface of the substrate on which the semiconductor light emitting element is mounted;
Forming a reflective layer by sputtering on at least a part of the surface of the substrate on which the semiconductor light emitting element is mounted that is not covered with the mask layer;
Forming a first opening in the reflective layer that exposes a wire bonding region provided on the surface of the base material by removing the mask layer. A method for manufacturing a substrate. Preparing a substrate;
Forming a mask layer having a predetermined pattern on at least a part of the surface of the substrate on which the semiconductor light emitting element is mounted;
A step of sequentially laminating the barrier layer and the reflective layer by sputtering on at least a part of the surface of the substrate on which the semiconductor light emitting element is mounted, which is not covered with the mask layer;
Forming a first opening and a second opening in the reflective layer and the barrier layer, respectively, exposing the wire bonding region provided on the surface of the substrate by removing the mask layer. A method for manufacturing a substrate for mounting a semiconductor light emitting element.   Either the semiconductor light emitting element mounting substrate according to claim 1 or 2 or the semiconductor light emitting element mounting substrate obtained by the method for manufacturing a semiconductor light emitting element mounting substrate according to any one of claims 3 to 6. The semiconductor light emitting device used.

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