JP2013004923A - Post attached reflector for semiconductor light-emitting device, resin package for semiconductor light-emitting device, and semiconductor light-emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a post attached reflector for a semiconductor light-emitting device which is excellent in heat resistance and light resistance, which has high reflectivity even in a thin thickness in a wide range of wavelength, and which is excellent in formability, heat dissipation and mass productivity.SOLUTION: A post attached reflector for a semiconductor light-emitting device is made of a silicone resin compact obtained by forming a liquid thermosetting silicon resin composition by liquid state injection molding. The silicon resin compact has the light reflectivity of 80% or more obtained by measuring a molded form sample of thickness 0.4 mm under a condition of wavelength 460 nm.

Description

  The present invention relates to a retroreflector for a semiconductor light-emitting device used for a lighting fixture, a display, a backlight of a mobile phone or a liquid crystal television, a digital signage, and other light sources, and a resin for a semiconductor light-emitting device formed by pasting the reflector The present invention relates to a package and a semiconductor light emitting device.

  A surface-mounted light-emitting device using a light-emitting element is small in size, has high power efficiency, and has a bright emission color. In addition, since this light emitting element is a semiconductor element, there is no fear of a broken ball. Furthermore, it has excellent initial drive characteristics and is strong against repeated on / off of vibration and lighting. Because of such excellent characteristics, light-emitting devices using light-emitting elements such as light-emitting diodes (LEDs) and laser diodes (LDs) are used as various light sources.

Such a semiconductor light-emitting device includes a light-emitting element electrically connected to a lead mounted on a resin package for a semiconductor light-emitting device having a resin molded body in which a lead and a resin composition are integrally molded. A basic configuration is a configuration in which the light-emitting element is covered with a sealing material.
The resin molded body constituting the package has a wall portion as a reflection frame (reflector) for increasing the reflection efficiency of light from the light emitting element, and the resin molded body is made of a thermoplastic resin such as polyamide. A thermoplastic resin composition containing a white pigment is widely used as a reflective material for increasing the light reflection efficiency.
By the way, a method is disclosed in which a portion (reflective frame) of a resin molded body for improving the reflection efficiency is separately formed, and this reflective frame is bonded to a circuit board using an adhesive. This method has the advantage that the degree of freedom in design for changing the bonding position to the circuit board is large, and the heat dissipation of the package obtained by combining with a circuit board with good heat dissipation improves. However, the disclosed method uses injection molding with a thermoplastic resin such as liquid crystal polymer, PBT, PPS, nylon, etc. from the viewpoint of mass production of the reflective frame, and has a low light resistance and is a thermosetting used for a sealing material. It has been pointed out that the adhesiveness to the adhesive resin is also inferior (see the prior art in Patent Document 1). In addition, these thermoplastic resin compositions have a problem of low reflectance.
In addition, such a reflective frame requires a complicated process in which molded products (reflective frames) that have been separated into pieces are arranged in order to be placed at predetermined positions on the circuit board, and then mechanically transported to the predetermined position. This process hindered mass production.

  As a method not using such a reflection frame, a method has been proposed in which a thermosetting resin such as an epoxy resin is used as in Patent Document 1 and a wiring board (circuit board) and a wall portion are integrally formed by transfer molding. In this method, although the adhesion to the substrate is improved, it is integrally molded with the wiring substrate, so the design flexibility is not easy and the specification change is not easy, and the transfer molding method is inferior in productivity, so the unit number of the product The mold cost is expensive, and the thermosetting resin is used for the wall, so that the light resistance, heat resistance and reflection characteristics are still insufficient.

JP 2008-252148 A

  Under such circumstances, the present invention is a retroreflector excellent in design freedom, which solves the above-mentioned problems of the prior art, has excellent heat resistance and light resistance, and has a high reflectance even in a thin wavelength range. An object of the present invention is to provide a retrofit reflector for a semiconductor light emitting device excellent in moldability and mass productivity, a method for manufacturing the reflector, a resin package for a semiconductor light emitting device to which the reflector is attached, and a semiconductor light emitting device having the resin package And

  As a result of intensive studies to solve the above problems, the present inventor has found that the following inventions meet the above object, and have reached the present invention.

  The reflector of the present invention comprises a silicone resin molded body obtained by liquid injection molding a liquid thermosetting silicone resin composition, and the resin molded body has a wavelength of 460 nm with respect to a molded body sample having a thickness of 0.4 mm. A retroreflector for a semiconductor light emitting device, which is a resin molded body having a light reflectance of 80% or more measured under the above conditions.

In the present invention, the “reflector” is a resin molded body having a wall portion for increasing the reflection efficiency of light from the light emitting element, and is also referred to as a reflection frame. The reflector of the present invention is not formed by integrally forming a circuit board on which a light-emitting element is mounted and a resin to form a reflection frame part, but separately forming a reflection frame and attaching it to the circuit board via an adhesive layer. Therefore, it is referred to as a retroreflector (simply referred to as “reflector”).
In the present invention, the “semiconductor light-emitting device” refers to the above-described reflector, a semiconductor light-emitting element mounted on a circuit board (hereinafter sometimes simply referred to as “light-emitting element”), and a light-emitting element. A light-emitting device containing at least a sealant.
In the present invention, the light emitting element before mounting is referred to as a “resin package for a semiconductor light emitting device” (hereinafter sometimes simply referred to as “package”).

The retroreflector for a semiconductor light-emitting device of the present invention is obtained by liquid injection molding a liquid thermosetting silicone resin composition, and is excellent in moldability, heat resistance, light resistance, reflectance, etc., and adheres to the circuit board. As a result, the light-emitting element can be easily placed, and the resin molded body constituting the wall portion has a reflectance of 460 nm light of a molded body sample having a thickness of 0.4 mm of 80% or more. Since it is molded with a certain thermosetting silicone resin composition, it is possible to maintain a high reflectivity with respect to visible light, and to provide a package rich in light resistance.
In addition, the specific method of the reflectance of light using the molded object sample of thickness 0.4mm is mentioned later with description of embodiment.

  In addition, the liquid thermosetting silicone resin composition of the present invention is suitable for the liquid injection molding (LIM) method, but the liquid injection molding (LIM) method can be continuously molded in large quantities. Suitable for production, does not generate useless cured products, and does not require secondary processing (that is, hardly generates burrs), making it possible to automate the reflector molding process, shorten the molding cycle, and reduce the cost of molded products There is a big merit. Comparing LIM molding and transfer molding, LIM molding has the advantage that the degree of freedom of the shape of the molded body is high, and the molding machine and mold price per unit production amount are relatively low.

  Furthermore, it is preferable that the resin molding which comprises the said wall part is a resin molding which becomes 60% or more of the light reflectivity measured on condition of wavelength 400nm about the molded object sample of thickness 0.4mm.

  Further, the Shore D hardness of the resin molded body is preferably 30 or more and 80 or less, and more preferably 35 or more and 75 or less. If the hardness is smaller than this range, the resulting reflector is likely to be deformed by stress and may be distorted when attached on the wiring board, or the optical design accuracy may be reduced. In addition, if it exceeds this range, chipping and cracking will occur when the reflectors that have been separated into pieces are transported by machine, and special and large-scale equipment such as a dicing device that uses a laser or blade will be required when separating into individual pieces. There is a risk of high costs.

  Moreover, it is desirable that the wall portion of the reflector has a tapered shape such that the thickness decreases toward the end portion. As a result, forward light extraction can be improved.

  Moreover, it is preferable that the side surface terminal part of the said wall part does not have a ridge corner part. With such a structure, the resin molded body constituting the hardened wall portion can be easily detached from the mold in the reflector manufacturing process.

  The reflector of this invention is affixed through the adhesive bond layer on the circuit board for mounting a semiconductor light-emitting device. As the adhesive, a modified silicone resin is preferably used.

  It is preferable that a heat sink is provided on the circuit board. By providing a heat sink, heat dissipation can be further improved.

  The circuit board has a multilayer structure of two or more layers, and a light emitting element can be mounted on at least one layer of the multilayer structure. Thereby, a circuit board having a complicated wiring pattern can also be used.

  The circuit board is an insulating glass epoxy substrate, polybutylene terephthalate (PBT) resin substrate, polyimide substrate, aluminum nitride substrate, boron nitride substrate, silicon nitride substrate, alumina ceramic substrate, glass substrate, flexible glass substrate, or insulating resin It is preferably at least one selected from the group consisting of an aluminum substrate having a layer and / or a hybrid substrate made of a copper substrate, and a plurality of printed wiring portions are formed.

  In the method for manufacturing a resin package for a semiconductor light emitting device according to the present invention, a liquid thermosetting silicone is formed in a space portion formed between the first mold and the second mold, having a dent corresponding to the reflector. It includes at least a step of filling the resin composition by a liquid injection molding method and a step of heating and curing the filled thermosetting silicone resin composition.

  As described above, since the resin molded body is formed by the liquid injection molding method, it is possible to manufacture a reflector having a concave portion with a complicated shape, and furthermore, since continuous molding is possible, it is suitable for mass production, Therefore, secondary processing is unnecessary, and there is an advantage that the molding process of the reflector can be automated, the molding cycle can be shortened, and the cost of the molded product can be reduced.

The reflector can be molded by individual molding that has been conventionally performed. In this case, it is preferable to use an isometric tournament type runner because the resin can be uniformly distributed to the individual reflector spaces of the mold.
The obtained reflector can be separated into individual pieces by, for example, a step of separating from the runner when the mold is opened and closed.
Separately divided reflectors need to be aligned once in order to adhere to the circuit board, and if it is more convenient for subsequent alignment not to be separated, it may be provided to the user with a runner. good. It is possible to easily cut and separate from the runner by pulling or tearing only by making a cut or providing a thin portion at the reflector cutting scheduled portion of the present invention.
As another aspect, the reflector can be molded into a sheet-like reflector molded body having a shape in which a plurality of reflectors are connected in a planar shape via a precut line. Such a molded body becomes runnerless molding, and the yield of the molding resin composition is increased, so that a package can be produced at low cost. This sheet-shaped reflector molded body may be separated into pieces by hand, but can be easily separated, aligned, and automatically bonded to the wiring board as follows, and is a reflector suitable for automatic mounting. Can be provided.
That is, the obtained sheet-like reflector molded body is a perforated sheet with a pre-cut line (cuts or thin portions provided for singulation), and the sheet-shaped reflector formed of the resin composition molded body of the present invention. The molded body can be easily separated from the planned cutting location by pulling, and has the advantage that an expensive dedicated jig such as a dicer is not required, and dust and debris may be produced during cutting. And has a characteristic that the cut surface is smooth.
For this reason, the sheet-shaped reflector molded body is attached to a resin sheet (expanded sheet) having flexibility and elongation characteristics via an adhesive on the back surface, and then this sheet is pulled vertically and horizontally to form a sheet. The reflector molded body is separated by a pre-cut line and can be separated into pieces in an aligned state. This aligned reflector can be automatically picked up by an image recognition device, transported to a predetermined position on the COB wiring board by a suction collet or the like, and pasted through an adhesive.

  The liquid thermosetting silicone resin composition is (A) a polyorganosiloxane, (B) a primary particle having an aspect ratio of 1.2 or more and 4.0 or less, and a primary particle diameter of 0.1 μm or more and 2.0 μm or less. A composition containing a pigment and (C) a curing catalyst is preferred.

  In particular, it is preferable that the center particle size of secondary particles of the (B) white pigment contained in the liquid thermosetting silicone resin composition is 0.2 μm or more and 5 μm or less, and further, the (B) white pigment is Alumina and / or titania are preferred.

In addition, the viscosity of the liquid thermosetting silicone resin composition at a shear rate of 100 s ⁻¹ at 25 ° C. is preferably in the range of 10 Pa · s to 10,000 Pa · s.
The details of (A) polyorganosiloxane, (B) white pigment, and (C) the viscosity of the curing catalyst and resin composition are described in the description of the embodiment.

The resin package for a semiconductor light-emitting device of the present invention is obtained by sticking the retroreflector for a semiconductor light-emitting device to a circuit board for mounting a semiconductor light-emitting element via an adhesive. The reflector may be attached to the circuit board by any method, but is preferably attached by automatic mounting. The adhesive layer refers to a thin layer of adhesive, but the thickness is not limited as long as the reflector can be attached to the circuit board.
When using an automatic mounting machine, it is necessary to align the reflectors after singulation by some means, but using the above-mentioned sheet-shaped reflector molded body makes it easy to divide, align, pick up, and paste. Can be done.
As an example, the sheet-like reflector molded body is attached to a resin sheet (expanded sheet) having flexibility and elongation properties via an adhesive on the back surface, and then this sheet is pulled vertically and horizontally, A sheet-like reflector molded body is separated by a pre-cut line and can be separated into pieces in an aligned state. This aligned reflector can be automatically picked up by an image recognition device, transported to a predetermined position on the COB wiring board by a suction collet or the like, and pasted through an adhesive. Preferred embodiments of the expand sheet and the adhesive adhesive will be described later.

  A semiconductor light-emitting device of the present invention comprises at least the resin package for a semiconductor light-emitting device, a semiconductor light-emitting element, and a sealing material that covers the semiconductor light-emitting element, and the semiconductor light-emitting element includes the semiconductor light-emitting device. It is electrically connected to the circuit board of the resin package for use.

ADVANTAGE OF THE INVENTION According to this invention, the retrofit reflector used for the resin package for semiconductor light-emitting devices which has high durability (light resistance, heat resistance), and can improve LED output by the outstanding reflectance, and its manufacturing method Provided.
According to the present invention, when pasting on the COB wiring board after separating the reflection frames in the conventional method, the complicated process of picking up and aligning the separated pieces is simplified. Is possible.

It is a schematic sectional drawing which shows an example of the semiconductor light-emitting device concerning embodiment of this invention. It is a schematic sectional drawing which shows the mounting state of the semiconductor light-emitting device concerning embodiment of this invention. It is a schematic sectional drawing which shows the mounting state of the semiconductor light-emitting device concerning other embodiment of this invention. FIG. 3 is a schematic cross-sectional view showing a manufacturing process of the semiconductor light emitting device according to the embodiment of FIG. 1. It is a conceptual diagram (perspective view) of a sheet-like reflector molded body. It is an enlarged view of the sheet-like reflector molded object of FIG. It is the figure which showed the one aspect | mode for dividing and aligning a reflector from a sheet-like reflector molded object.

  Hereinafter, a retrofit reflector for a semiconductor light-emitting device according to the present invention, a manufacturing method thereof, a resin package for a semiconductor light-emitting device formed by attaching the reflector, and a semiconductor light-emitting device having the package will be described using embodiments and examples. explain. However, the present invention is not limited to this embodiment and example.

<1. Overview of Semiconductor Light Emitting Device>
FIG. 1 shows a schematic cross-sectional view of an embodiment of a semiconductor light emitting device having a package of the present invention.
A semiconductor light emitting device 1 in FIG. 1 includes a reflector (resin molded body) 2, a light emitting element 3 placed on a circuit board 10, and a sealing material 4 that covers the light emitting element 3.
The reflector 2 includes a wall portion 20 that is molded around the light emitting element 3, and is attached to the circuit board 10 via an adhesive 30. The circuit board 10 is obtained by forming a first printed wiring portion 11 and a second printed wiring portion 12 on the surface of a base substrate 13. The side on which the light emitting element 3 is placed is called the upper side of the circuit board, and the opposite side is called the lower side of the circuit board.

The light-emitting element 3 has a pair of positive and negative first electrodes 3a and second electrodes 3b on the same surface side, and the respective electrodes are connected to the first printed wiring portion 11 and the second printed wiring portion 12, respectively. Electrically connected.
The semiconductor light emitting device 1 of FIG. 1 will be described as having a pair of positive and negative electrodes on the same surface side. However, when using a light emitting element having a pair of positive and negative electrodes on the upper and lower surfaces, The electrode is directly electrically connected to the first printed wiring portion 11 using a conductive die bond material or the like, and the electrode on the upper surface may be wire bonded to the second printed wiring portion 12 by the above-described method.

The light emitting element 3 is placed on the first printed wiring portion 11 via a die bond member.
The first printed wiring portion 11 is electrically connected to the first electrode 3a of the light emitting element 3 via the wire 5a. The second printed wiring portion 12 is electrically connected to the second electrode 3b of the light emitting element 3 via the wire 5b. Note that the light emitting element 3 does not necessarily have to be placed on the first printed wiring portion 11, and may be placed on the circuit board 10.

  In the portion where the light emitting element 3 is placed, a recess is formed by the wall portion 20 and the circuit board 10. The recess has a bottom surface 10a (an upper surface of the circuit board 10) and a side surface 20a (a side surface of the wall portion 20). The first printed wiring portion 11 is exposed from the bottom surface 10a of the recess. The light emitting element 3 is mounted on the exposed portion via a die bond member. The wall part 20 is shape | molded by carrying out liquid injection molding of the liquid thermosetting silicone resin composition. The opening of the recess is wider than the bottom surface 10a, and the side surface 20a can be tapered.

The sealing material 4 is inserted into a recess formed by the circuit board 10 and the wall portion 20 of the package 2 so as to cover the light emitting element 3.
As the sealing material 4, a thermosetting resin or a composition containing a thermosetting resin as a main component (hereinafter collectively referred to as “thermosetting resin composition for sealing material”) is used. In the case of directly using the light, transparent sealing is performed. However, in the case where the light of the light emitting element 3 is converted into an arbitrary wavelength, a phosphor is usually contained.
The wall 20 and the sealing material 4 are made of thermosetting resin, and the physical properties such as the expansion coefficient are close, so that the adhesion is very good. In addition, with the above structure, a semiconductor light emitting device having excellent heat resistance, light resistance, and the like can be provided.

  Hereinafter, each component of the semiconductor light emitting device will be described in detail.

<2. Resin package for semiconductor light emitting devices>
<2.1. Circuit board>
The circuit board 10 is obtained by forming a first printed wiring portion 11 and a second printed wiring portion 12 on the surface of a base substrate 13 which is a base.
The first printed wiring part 11 and the second printed wiring part 12 are electrically insulated with a predetermined distance.

  The material of the base substrate 13 that is the base of the circuit board 10 is a board-like hard material that is electrically insulating and hardly deformed by reflow soldering heat. Insulating glass epoxy substrate, polybutylene terephthalate (PBT) resin substrate, polyimide substrate, aluminum nitride substrate, boron nitride substrate, silicon nitride substrate, alumina ceramic substrate, glass substrate, flexible glass substrate, insulation It is preferably formed of at least one selected from the group consisting of an aluminum substrate having a resin layer and / or a hybrid substrate consisting of a copper substrate, and in particular, a glass epoxy substrate and an aluminum substrate having an insulating resin layer are preferable. In addition, a printed wiring silicon substrate, silicon carbide substrate, sapphire substrate, or the like can be used.

  The 1st printed wiring part 11 and the 2nd printed wiring part 12 can be comprised using electrical good conductors, such as iron, phosphor bronze, and a copper alloy. Moreover, in order to improve the reflectance of the light from the light emitting element 3, the surface of the 1st printed wiring part 11 and the 2nd printed wiring part 12 can also give metal plating, such as silver, aluminum, copper, and gold | metal | money. . Moreover, in order to improve the reflectance of the surface of the 1st printed wiring part 11 and the 2nd printed wiring part 12, it is preferable to make it smooth. Moreover, in order to improve heat dissipation, the area of the 1st printed wiring part 11 and the 2nd printed wiring part 12 can be enlarged. Thereby, the temperature rise of the light emitting element 3 can be effectively suppressed, and a relatively large amount of electricity can be passed through the light emitting element 3. Moreover, heat dissipation can be improved by making the 1st printed wiring part 11 and the 2nd printed wiring part 12 thick.

  The first printed wiring part 11 and the second printed wiring part 12 are a pair of positive and negative electrodes. The first printed wiring unit 11 and the second printed wiring unit 12 may be at least one each, but a plurality of the first printed wiring unit 11 and the second printed wiring unit 12 may be provided. In addition, when a plurality of light emitting elements 3 are mounted on the first printed wiring portion 11, it is necessary to provide a plurality of second printed wiring portions 12. As the pattern of the printed wiring portion, an arbitrary shape can be selected as necessary.

  The portion of the circuit board 10 to which the reflector is bonded is preferably a smooth surface including the printed wiring portion and the base substrate so that the reflector can be bonded without a gap.

<2.2. Reflector>
The reflector 2 constituting the wall portion 20 is formed by liquid injection molding of a liquid thermosetting silicone resin composition, and the light emitting element 3 on the circuit board 10 is placed in order to reflect light from the light emitting element 3. The circuit board is formed in close contact with the circuit board by an adhesive.

The resin molding which comprises the reflector 2 consists of a liquid thermosetting silicone resin composition which has a high reflectance about visible light after hardening.
Specifically, the reflectance of the resin molded body requires that the reflectance of light at 460 nm is 80% or more for a molded body sample having a thickness of 0.4 mm, and more preferably 90% or more.
Further, the reflectance of light having a wavelength of 400 nm is preferably 60% or more, more preferably 80% or more, and still more preferably 90% or more for a molded sample having a thickness of 0.4 mm.
Here, the molded body sample having a thickness of 0.4 mm can be obtained by curing the liquid thermosetting silicone resin composition as a raw material at 180 ° C. for 4 minutes under a pressure of 10 kg / cm ² , for example. it can.
This reflectance can be measured using a colorimeter such as SPECTROPHOTOMETER CM-2600d manufactured by Konica Minolta Co., Ltd., by producing a molded sample having a thickness of 0.4 mm. When only a compact shaped body such as a package is available, a sample having a thickness of 0.4 mm is prepared by polishing the package and the like, and a minute surface reflectance such as Nippon Denshoku VSR400 is used as a reflectance measuring device. Using a meter, it can be obtained by measuring the reflectance in an area of 0.05 mmφ or more.
In addition, the reflectance of a resin molding can be controlled by the kind of resin, the kind of filler, the particle size of filler, content, etc.
The physical properties of the liquid thermosetting silicone resin composition will be described later.

The wall portion 20 of the reflector 2 preferably has a taper (inclined) shape whose thickness decreases toward the end portion, and the recess formed by the circuit board 10 and the wall portion 20 has an opening direction. It has become a wide mouth. As a result, the light extraction efficiency in the forward direction is improved, and the mold releasability during liquid injection molding is improved. Further, the taper is preferably smooth, but can be provided with unevenness. This is because the unevenness of the interface between the wall portion 20 and the sealing material 4 can be improved by providing the unevenness. The inclination angle of the concave portion is preferably 95 ° or more and 150 ° or less, particularly preferably 100 ° or more and 120 ° or less, as measured from the bottom surface.
In addition, when the wall 20 is liquid injection molded using a liquid thermosetting silicone resin composition, the mold releasability is improved, so that molding defects can be suppressed and the molding cycle time can be shortened. A light-emitting device having excellent properties can be provided.

  Moreover, although the side surface end part 20b of the wall part 20 in this embodiment has a ridge angle part, it is good also as a structure which does not have a ridge angle part.

  Hereinafter, the thermosetting silicone resin composition constituting the reflector 2 will be described in detail.

<3. Thermosetting silicone resin composition>
<3.1. Characteristics of thermosetting silicone resin composition>
<3.1.1. Composition of thermosetting silicone resin composition>
The thermosetting silicone resin composition that is the material of the wall portion 20 contains (A) a polyorganosiloxane, (B) a white pigment, and (C) a curing catalyst as main components and, if necessary, other components.
Examples of other components include (D) a curing rate control agent and (E) a fluidity modifier.
In particular, it contains (A) a polyorganosiloxane, (B) a white pigment having an aspect ratio of primary particles of 1.2 to 4.0, a primary particle diameter of 0.1 to 2.0 μm, and (C) a curing catalyst. The thermosetting silicone resin composition formed is suitable.
The preferable composition of the thermosetting silicone resin composition for the resin molded body for a semiconductor light-emitting device used in the present invention for the components (A) to (C) is as follows.
The content of (A) polyorganosiloxane in the thermosetting silicone resin composition used in the present invention is not limited as long as it can be normally used as a resin molding material for forming the wall portion. It is 15 to 50 weight% of the whole material, Preferably it is 20 to 40 weight%, More preferably, it is 25 to 35 weight%.
Further, the content of the white pigment (B) in the composition is not limited as long as it can be normally used as a material for a resin molded body for forming the wall portion. For example, 30% by weight of the entire composition The content is 85% by weight or less, preferably 40% by weight or more and 80% by weight or less, more preferably 45% by weight or more and 70% by weight or less.

<3.1.2. Viscosity of thermosetting silicone resin composition>
The thermosetting silicone resin composition used in the present invention preferably has a viscosity of 10 Pa · s to 10,000 Pa · s at a shear rate of 100 s ⁻¹ at 25 ° C. The viscosity is more preferably 150 Pa · s or more and 1,000 Pa · s or less from the viewpoint of molding efficiency when molding a resin molded body for a semiconductor device.

In particular, in LIM molding using a liquid resin material, burrs due to the material seeping out from minute gaps in the mold are likely to occur, and usually a post-treatment process for removing the burrs is necessary. If the gap between the molds is reduced to suppress the occurrence, short mold (unfilled) is likely to occur. However, when the viscosity of the liquid thermosetting silicone resin composition is in the above range, Therefore, the LIM molding of the resin molded body can be easily and efficiently performed.
If the viscosity at a shear rate of 100 s ^-1 is greater than 10,000 Pa · s, the resin flow is poor, so that filling of the mold becomes insufficient, or it takes time to supply the liquid resin composition when performing injection molding. Therefore, the molding efficiency tends to decrease, for example, the molding cycle becomes longer.
Further, if the viscosity is less than 10 Pa · s, the liquid resin composition leaks from the gap between the molds to generate burrs, or the injection pressure easily escapes into the gap between the molds, so that molding becomes difficult to stabilize. As a result, the molding efficiency tends to decrease. In particular, when the molded body is small, post-processing for removing burrs becomes difficult, so it is important for moldability to suppress the generation of burrs.

In addition, from the viewpoint of thixotropy, the thermosetting silicone resin composition used in the present invention has a viscosity ratio (1 s at a shear rate of 1 s ⁻¹ at 25 ° C. to a viscosity at a shear rate of 100 s ⁻¹ at 25 ° C. preferably ^-1 / 100s ^-1) it is 15 or more, and particularly preferably 30 or more. On the other hand, the upper limit is more preferably 300 or less.

  In order to make a material with good moldability, it is necessary to provide the material with a certain level of thixotropy. However, by satisfying the above conditions, there are few burrs and short molds (unfilled). The material measurement time and molding cycle during molding can be shortened, the molding is easy to stabilize, and the material has high molding efficiency.

When the ratio of the viscosity at a shear rate of 1 s ⁻¹ at 25 ° C. to the viscosity at a shear rate of 100 s ⁻¹ at 25 ° C. is less than 15, that is, when the viscosity at the shear rate of 1 s ⁻¹ is relatively small, molding is performed. Molding is easy because the material can easily enter the gaps between the machine and the mold, causing burrs, dripping easily at the nozzle part, and the injection pressure is not easily transmitted to the material, making molding difficult to stabilize. Can be difficult to control. In LIM molding, resin leakage in the parting line of the sprue part tends to be a problem, but adjusting to the above viscosity range is also effective in suppressing resin leakage.
The viscosity at a shear rate of 100 s ⁻¹ and the viscosity at a shear rate of 1 s ⁻¹ at 25 ° C. are measured using, for example, an ARES-G2-strain-controlled rheometer (manufactured by TA Instruments Japan Co., Ltd.). Can be measured.

<3.2. Components of Thermosetting Silicone Resin Composition>
<(A) Polyorganosiloxane>
The polyorganosiloxane in the present invention refers to a polymer substance in which an organic group is added to a structure having a portion in which a silicon atom is bonded to another silicon atom through oxygen. Here, the polyorganosiloxane is preferably a liquid at normal temperature and pressure. This is because the material becomes easy to handle when molding the resin molded body for a semiconductor light emitting device. Polyorganosiloxane that is solid under normal temperature and normal pressure generally has a relatively high hardness as a cured product, but has low energy required for destruction and low toughness, light resistance and heat resistance are insufficient, This is because many products tend to discolor due to heat.

The polyorganosiloxane usually refers to an organic polymer having a siloxane bond as the main chain, and examples thereof include compounds represented by the following general composition formula (1) and mixtures thereof.
(R ¹ R ² R ³ SiO _1/2 ) _M (R ⁴ R ⁵ SiO _2/2 ) _D (R ⁶ SiO _3/2 ) _T (SiO _4/2 ) _Q (1)
Here, in the above formula (1), R ¹ to R ⁶ are independently selected from an organic functional group, a hydroxyl group, and a hydrogen atom. M, D, T, and Q are 0 or more and less than 1, and M + D + T + Q = 1.
The organic functional group may be arbitrarily selected from known monovalent organic groups as long as it does not impair the light and heat durability, curing characteristics, and reflection characteristics of the obtained resin molded body. Alkyl groups, aromatic groups, alkenyl groups, and alkoxy groups having 1 to 3 carbon atoms are preferable because the resin molding is difficult to be colored by heat, and among them, methyl groups, phenyl groups, and vinyl groups are industrially readily available for light. It is preferable because it is stable, and it is particularly preferable that the polyorganosiloxane and the resin molding have a methyl group mainly from the viewpoint that the bifunctional silicon content can be increased and a flexible resin molding can be obtained.
The unit constituting the main polyorganosiloxane is monofunctional [R ₃ SiO _0.5 ] (triorganosyl hemioxane), bifunctional [R ₂ SiO] (diorganosiloxane), trifunctional [RSiO _1.5 ] (Organosilsesquioxane), tetrafunctional [SiO ₂ ] (silicate), and by changing the composition ratio of these four types of units, the difference in the properties of polyorganosiloxane appears, so the desired properties May be selected as appropriate so that is obtained.

Polyorganosiloxane can be cured by applying heat energy, light energy, or the like in the presence of a curing catalyst. Here, curing refers to changing from a state showing fluidity to a state showing no fluidity. For example, even if the object is left at an angle of 45 degrees from the horizontal for 30 minutes, it is fluid. The state is referred to as an uncured state, and a state having no fluidity can be determined as a cured state. Further, when the object does not exhibit fluidity due to a large filler filling amount, the object is not plastically deformed, and the hardness can be measured with a durometer type A, and the measured hardness value is at least 5 or more. Whether it is uncured or cured can also be determined.
When the polyorganosiloxane is classified according to the curing mechanism, polyorganosiloxanes such as an addition polymerization curing type, a condensation polymerization curing type, an ultraviolet curing type, and a peroxide crosslinking type can be generally exemplified. Among these, addition polymerization curing type (addition type polyorganosiloxane) and condensation curing type (condensation type polyorganosiloxane) are preferable. Among these, a polyorganosiloxane type that has no by-products and cures by irreversible hydrosilylation (addition polymerization) is more preferable. This is because when a by-product is generated during the molding process, the pressure in the molded container tends to increase or it remains as foam in the cured material.

  Addition type polyorganosiloxane refers to a polyorganosiloxane chain crosslinked by an organic addition bond. As a typical example, the molar ratio of the total hydrosilyl group amount to the total alkenyl group amount of a silicon-containing compound having an alkenyl group such as vinylsilane and a silicon compound containing a hydrosilyl group such as hydrosilane is 0.5 times. Examples thereof include compounds having Si—C—C—Si bonds at the cross-linking points obtained by mixing in an amount ratio of 2.0 times or less and reacting in the presence of an addition condensation catalyst such as a Pt catalyst. .

  Examples of the condensed polyorganosiloxane include a compound having a Si—O—Si bond obtained by hydrolysis and polycondensation of an alkylalkoxysilane at a crosslinking point.

<(B) White pigment>
The white pigment (B) used in the present invention preferably has a primary particle aspect ratio of 1.2 or more and 4.0 or less, and a primary particle diameter of 0.1 μm or more and 2.0 μm or less, and does not hinder the curing of the resin. A known white pigment can be appropriately selected. As the white pigment, inorganic and / or organic materials can be used. Here, white means colorless and not transparent. That is, it means a color that can diffusely reflect incident light by a substance that does not have a specific absorption wavelength in the visible light region.

Examples of the inorganic particles that can be used as the white pigment include alumina (hereinafter sometimes referred to as “aluminum oxide”), silicon oxide, titania (hereinafter sometimes referred to as “titanium oxide”), zinc oxide, Metal oxides such as magnesium oxide and zirconium oxide; metal salts such as calcium carbonate, barium carbonate, magnesium carbonate and barium sulfate; boron nitride, alumina white, colloidal silica, aluminum silicate, zirconium silicate, aluminum borate, clay, Examples include talc, kaolin, mica, and synthetic mica.
Among these, alumina, titania, zinc oxide, zirconium oxide, and the like are preferable from the viewpoint of high whiteness and high light reflection effect and hardly change in quality, and alumina and titania are particularly preferable. Also, alumina, boron nitride, and the like are particularly preferable from the viewpoint of improving the thermal conductivity when the material is cured. Alumina is particularly preferable from the viewpoint of high near-ultraviolet light reflection effect and small alteration due to near-ultraviolet light. Titania can be contained to such an extent that problems such as photocatalytic properties, dispersibility, and whiteness do not occur.
These white pigments can be used alone or in admixture of two or more.

  As the refractive index difference between (A) the polyorganosiloxane and (B) the white pigment is larger, the whiteness is higher just by adding a small amount of white pigment, and the resin molding for semiconductor light-emitting devices has better reflection and scattering efficiency. You can get a body. The polyorganosiloxane (A) preferably has a refractive index of about 1.41, and alumina particles having a refractive index of 1.76 can be suitably used as the (B) white pigment.

  Alumina has a low ability to absorb ultraviolet rays, and therefore can be suitably used particularly when used with a light emitting element emitting ultraviolet to near ultraviolet light. The alumina used in the present invention is not limited in crystal form, but α-alumina having characteristics such as chemically stable, high melting point, high mechanical strength, high hardness, and high electric insulation resistance is preferable. Can be used.

In the present invention, when alumina is used as the white pigment (B), the crystallite size of the alumina crystal is preferably 500 to 2,000, more preferably 700 to 1,500, and more preferably 900 to It is particularly preferable that it is 1,300 mm or less. A crystallite is the largest group that can be regarded as a single crystal.
When the crystallite size of the alumina crystal is within the above range, it is preferable in that the pipe, screw, mold, and the like during the molding are less worn and impurities due to the wear are less likely to be mixed. The crystallite size can be confirmed by X-ray diffraction measurement.

In general, alumina has higher durability than titania, and when alumina and titania are used in combination, the durability of the material tends to decrease as the ratio of titania increases. On the other hand, titania has a higher refractive index than alumina and a large difference in refractive index from resin, so that the reflectance of the wall tends to increase as the titania ratio increases.
Therefore, when titania having the same or lower degree is added to alumina, the reflectance is improved more than expected from the titania ratio, and the decrease in durability can be suppressed as much as possible while increasing the reflectance of the material.

  The thermal conductivity during curing of the thermosetting silicone resin composition is preferably higher from the viewpoint of molding efficiency and heat dissipation of the semiconductor light emitting device, but in order to increase the thermal conductivity, the purity is 98% or more. It is preferable to use alumina, more preferably alumina having a purity of 99% or more, and particularly preferably low soda alumina. In order to increase the thermal conductivity, it is also preferable to use boron nitride, and it is particularly preferable to use boron nitride having a purity of 99% or more.

In particular, in a semiconductor light emitting device using a light emitting element having an emission peak wavelength of 420 nm or more, titania can also be suitably used as a white pigment. Although titania has an ultraviolet absorbing ability, it has a high refractive index and a strong light scattering property. Therefore, it has a high reflectance of light having a wavelength of 420 nm or more, and it is easy to exhibit high reflection even with a small addition amount. When titania is used as the white pigment of the present invention, a rutile type that is stable at high temperature, has a high refractive index, and has a relatively high light resistance is more stable than an anatase type that has a large ultraviolet absorbing ability and photocatalytic ability and is unstable at high temperature. A rutile type in which a surface is coated with a thin film of silica or alumina for the purpose of suppressing photocatalytic activity is particularly preferable.
Since titania has a high refractive index and a large difference in refractive index with polyorganosiloxane, it is easy to be highly reflective even with a small addition amount. Therefore, alumina and titania are used in a ratio of 50:50 to 95: 5 (weight ratio). May be.

The white pigment (B) used in the present invention preferably has an aspect ratio of primary particles of 1.2 or more and 4.0 or less.
The aspect ratio is generally used as a simple method for quantitatively expressing the shape of a particle. In the present invention, the major axis length (maximum major axis) of a particle measured by observation with an electron microscope such as SEM is the minor axis length. It is obtained by dividing by the length (the length of the longest part perpendicular to the major axis). When the axial length varies, a plurality of points (for example, 10 points) can be measured with an SEM and calculated from the average value. Alternatively, the same calculation result can be obtained by measuring 30 points and 100 points.
A preferred aspect ratio is 1.25 or more, more preferably 1.3 or more, and particularly preferably 1.4 or more. On the other hand, the upper limit is preferably 3.0 or less, more preferably 2.5 or less, still more preferably 2.2 or less, particularly preferably 2.0 or less, and most preferably 1.8 or less.
When the aspect ratio is in the above range, high reflectance is likely to be exhibited by scattering, and the reflection of light having a short wavelength in the near ultraviolet region is particularly large. Thereby, in the semiconductor light-emitting device using this resin molding, LED output can be improved.
In addition, the use of a white pigment having an aspect ratio in the above range is preferable in terms of molding because, for example, the mold is less worn. When the aspect ratio is larger than the above range, the mold may be worn by contact with the pigment particles. Conversely, when using a white pigment with a small aspect ratio, the packing density of the pigment in the material may be reduced. Since the height can be increased, the frequency of contact between the mold and the pigment increases, and the mold tends to wear. Furthermore, when white pigments with an aspect ratio in the above range are used, the material viscosity can be easily adjusted and adjusted to a viscosity suitable for molding, so that the molding cycle can be shortened and burrs can be prevented. An excellent material.

When the aspect ratio is in the above range, the white pigment is filled in the gaps of the mold and burrs are less likely to occur, but when the aspect ratio is nearly spherical, such as less than 1.2, the burrs pass through the gaps of the mold. Is likely to occur.
In the present invention, the particles whose aspect ratio falls within the above range preferably occupies 60% by volume or more, more preferably 70% by volume or more, and particularly preferably 80% by volume or more of the entire white pigment (B). (B) It is a matter of course for those skilled in the art that the white pigment does not have to satisfy the above aspect ratio range.

  In order to set the aspect ratio within the above range, a general method such as surface treatment or polishing of the white pigment may be employed. It can also be adjusted by crushing (pulverizing) the white pigment to make it fine, or by classifying it with sieve powder or the like.

  The white pigment (B) used in the present invention is preferably a crushed shape, a rounded shape with few crystal corners by treatment after crushing, or a non-spherical pigment produced by firing or the like. Shape is also included.

Moreover, (B) the primary particle diameter of the white pigment is preferably 0.1 μm or more and 2 μm or less. The lower limit is preferably 0.15 μm or more, more preferably 0.2 μm or more, particularly preferably 0.25 μm or more, and the upper limit is preferably 1 μm or less, more preferably 0.8 μm or less, particularly preferably 0. .5 μm or less.
When the primary particle size is in the above range, the material is easy to express high reflectivity by combining the backscattering tendency and the scattered light intensity, and the reflection with respect to light having a short wavelength particularly in the near ultraviolet region is increased, which is preferable. .
If the primary particle diameter is too small, the white pigment tends to have low reflectance because the scattered light intensity is low.If the primary particle diameter is too large, the scattered light intensity tends to increase, but the reflectance tends to be forward scattering. It tends to be smaller.
Further, when the primary particle diameter is in the above range, it is preferable from the viewpoint of moldability, such as easy adjustment to a viscosity suitable for molding and less wear of the mold. When the primary particle diameter is larger than the above range, the impact on the mold due to contact with the pigment particles tends to be large and the wear of the mold tends to be severe, and when using a white pigment whose primary particle diameter is smaller than the above range However, since the material tends to be highly viscous and the filling amount of the white pigment cannot be increased, it tends to be difficult to achieve compatibility between material properties such as high reflection and moldability.
In particular, in order to obtain a material that can be suitably used for liquid injection molding, it is necessary that the material has a thixotropic property of a certain level or more. Adding a white pigment with a primary particle size of 0.1 μm or more and 2.0 μm or less to the composition has a large thixotropy-imparting effect and makes it easy to mold with few burrs and shorts, so viscosity and thixotropy are easy. Can be adjusted.
A white pigment having a primary particle diameter larger than 2 μm can be used in combination for the purpose of increasing the filling rate of the white pigment in the resin composition.

  The primary particle in the present invention refers to the smallest unit that can be clearly distinguished from other particles constituting the powder, and the primary particle diameter can be measured by observation with an electron microscope such as SEM. On the other hand, agglomerated particles formed by agglomeration of primary particles are called secondary particles. The center particle size of secondary particles is determined by dispersing the powder in a suitable dispersion medium (for example, water in the case of alumina) and using a particle size analyzer. Can be measured. When the primary particle size varies, several points (for example, 10 points) are observed with an SEM, and the average value may be set as the particle size. In the measurement, when each particle is not spherical, the longest length, that is, the length of the major axis is taken as the particle diameter.

On the other hand, the white pigment preferably has a secondary particle central particle size (hereinafter sometimes referred to as “secondary particle size”) of 0.2 μm or more, and 0.3 μm or more. More preferred. The upper limit is preferably 5 μm or less, more preferably 3 μm or less, and even more preferably 2 μm or less.
When the secondary particle size is in the above range, the moldability of liquid injection molding becomes good, which is preferable. In addition, it is easy to adjust to a viscosity suitable for molding, and there is little wear on the mold. In addition, since the white pigment does not easily pass through the gap between the molds, burrs are not easily generated, and the mold gate is not easily clogged, so that troubles during molding hardly occur. When the secondary particle size is larger than the above range, the material tends to become non-uniform due to the precipitation of the white pigment, the moldability is impaired due to mold wear and gate clogging, and the reflection of the molded product is Uniformity may be impaired.
In addition, for the purpose of increasing the filling rate of the white pigment in the resin composition, a white pigment having a secondary particle size larger than 10 μm can be used in combination. The central particle diameter means a particle diameter at which the volume integrated value of the volume-based particle size distribution curve becomes 50%, and generally refers to what is called 50% particle diameter (D ₅₀ ) and median diameter.

In the present invention, the content of the (B) white pigment in the resin molded body material for a semiconductor light emitting device is appropriately selected depending on the particle diameter and type of the pigment used and the difference in refractive index between the polyorganosiloxane and the pigment, and is not particularly limited. For example, the content in the composition is usually 30% by weight or more, preferably 45% by weight or more, and usually 85% by weight or less, preferably 70% by weight or less.
When it is within the above range, reflectivity, moldability and the like are good. If it is less than the above lower limit, light tends to be transmitted and the reflection efficiency of the semiconductor light emitting device tends to decrease, and if it is larger than the upper limit, the fluidity of the material tends to deteriorate and the moldability tends to decrease. is there.
Further, in order to increase the thermal conductivity of the thermosetting silicone resin composition, for example, in the range of 0.4 to 3.0, (B) alumina and / or titania as a white pigment is a resin molded product. It is preferable to add 40 to 90 parts by weight with respect to the total amount of the material.
Alternatively, it is preferable to add boron nitride as a white pigment in an amount of 30 parts by weight or more and 90 parts by weight or less based on the total amount of the resin molding material. Alumina, titania, and boron nitride may be used in combination.

<3.2.3. (C) Curing catalyst>
The (C) curing catalyst in the present invention is a catalyst for curing the polyorganosiloxane of (A). This catalyst includes an addition polymerization catalyst and a condensation polymerization catalyst depending on the curing mechanism of the polyorganosiloxane.

  The addition polymerization catalyst is a catalyst for promoting the addition reaction between the alkenyl group and the hydrosilyl group in the component (A). Examples of the addition polymerization catalyst include platinum black, second platinum chloride, platinum chloride. Examples include acids, reaction products of chloroplatinic acid and monohydric alcohol, complexes of chloroplatinic acid and olefins, platinum-based catalysts such as platinum bisacetoacetate, platinum-based catalysts such as palladium-based catalysts and rhodium-based catalysts. . The amount of addition polymerization catalyst is usually 1 ppm or more, preferably 2 ppm or more, usually 100 ppm or less, preferably 50 ppm or less, more preferably 20 ppm or less, based on the weight of component (A) as a platinum group metal. It is.

  As a catalyst for condensation polymerization, acids such as hydrochloric acid, nitric acid, sulfuric acid, organic acids, alkalis such as ammonia and amines, organic boron compounds such as boron alkoxides, metal chelate compounds, and the like can be used. A metal chelate compound containing any one or more of Ti, Ta, Zr, Al, Hf, Zn, Sn, Ga, and Pt can be used. Among them, the metal chelate compound preferably contains one or more of Ti, Al, Zn, Zr, and Ga, and more preferably contains Zr.

The blending amount of the catalyst for condensation polymerization is usually 0.01% by weight or more, preferably 0.05% by weight or more, while the upper limit is usually 10% by weight or less, preferably 6% by weight based on the total weight of the component (A). % Or less.
When the addition amount of the catalyst is within the above range, the curability and storage stability of the resin molded body material for a semiconductor light emitting device are good, and the quality of the molded resin molded body is also good. If the added amount exceeds the upper limit value, there may be a problem in the storage stability of the resin molded body material. If it is less than the lower limit value, the curing time becomes longer and the productivity of the resin molded body decreases. There is a tendency for quality to decline.
These catalysts are selected in consideration of the stability of the resin composition for a semiconductor light emitting device, the hardness of the coating, non-yellowing, curability and the like.

<Others>
It is preferable that the material for a resin molded body for a semiconductor light emitting device of the present invention further contains a curing rate control agent. Here, the curing rate control agent is for controlling the curing rate in order to improve the molding efficiency when molding the resin molding material, and includes a curing retarder or a curing accelerator.

The curing retarder is an important component particularly in liquid injection molding of an addition polymerization type polyorganosiloxane composition having a high curing rate.
Examples of the curing retarder in the addition polymerization reaction include compounds containing an aliphatic unsaturated bond, organic phosphorus compounds, organic sulfur compounds, nitrogen-containing compounds, tin compounds, organic peroxides, and the like. It doesn't matter.
Examples of the compound containing an aliphatic unsaturated bond include 3-hydroxy-3-methyl-1-butyne, 3-hydroxy-3-phenyl-1-butyne, and 3- (trimethylsilyloxy) -3-methyl-1-butyne. And propargyl alcohols such as 1-ethynyl-1-cyclohexanol, ene-yne compounds, and maleic acid esters such as dimethyl malate.
Examples of the curing retarder in the condensation polymerization reaction include compounds having a reaction with hydrogen or a hydrogen bond, such as lower alcohols having 1 to 5 carbon atoms, amines having a molecular weight of 500 or less, organic compounds containing nitrogen or sulfur, and epoxy group-containing compounds. .

  By selecting the type and blending amount of the curing rate control agent according to the purpose, molding of the resin molded body material becomes easy. For example, there is an advantage that the filling rate into the mold becomes high or there is no leakage from the mold when molding by injection molding, and burrs are hardly generated.

The thermosetting silicone resin composition, which is a wall forming material, contains one or more other components in any ratio and combination as required, as long as the effects of the present invention are not impaired. be able to.
For example, a fluidity adjusting agent can be contained for the purpose of controlling fluidity of the thermosetting silicone resin composition and suppressing sedimentation of white pigment.
The fluidity modifier is not particularly limited as long as it is a solid particle from the normal temperature to the molding temperature where the viscosity of the thermosetting silicone resin composition is increased by addition, for example, silica fine particles, quartz beads, glass beads, etc. Examples thereof include inorganic particles, inorganic fibers such as glass fibers, boron nitride, and aluminum nitride.

Further, in order to adjust the viscosity of the thermosetting silicone resin composition, a non-curable polyorganosiloxane can be partially blended with the (A) polyorganosiloxane as a liquid thickener.
The blending amount of the polyorganosiloxane as the liquid thickener is usually 0 to 10 parts by weight, preferably 0.1 to 5 parts by weight, more preferably 0, when the total amount of the polyorganosiloxane (A) is 100 parts by weight. About 5 to 3 parts by weight can be used in place of (A).

In addition to the above components, the thermosetting silicone resin composition may contain inorganic fibers such as glass fibers for the purpose of increasing the strength and toughness after thermosetting, and has a thermal conductivity. In order to increase it, boron nitride, aluminum nitride, fibrous alumina or the like having high thermal conductivity can be contained separately from the aforementioned white pigment. In addition, for the purpose of lowering the linear expansion coefficient of the cured product, quartz beads, glass beads and the like can be contained.
If the content when adding these is too small, the desired effect can not be obtained, and if it is too large, the viscosity of the thermosetting silicone resin composition increases and affects the workability, so a sufficient effect is expressed. It can select suitably in the range which does not impair the workability of material. Usually, it is 500 parts by weight or less, preferably 200 parts by weight or less with respect to 100 parts by weight of the polyorganosiloxane.

  In addition, the thermosetting silicone resin composition includes an ion migration (electrochemical migration) inhibitor, an anti-aging agent, a radical inhibitor, an ultraviolet absorber, an adhesion improver, a flame retardant, a surfactant, Storage Stabilizer, Ozone Degradation Prevention Agent, Light Stabilizer, Thickener, Plasticizer, Coupling Agent, Antioxidant, Thermal Stabilizer, Conductivity Adder, Antistatic Agent, Radiation Blocker, Nucleating Agent, Phosphorus A system peroxide decomposer, a lubricant, a pigment, a metal deactivator, a physical property modifier, and the like can be contained within a range that does not impair the object and effect of the present invention.

<Composition ratio of composition>
The content of (A) polyorganosiloxane in the thermosetting silicone resin composition is usually 15% by weight or more and 50% by weight or less, preferably 20% by weight or more and 40% by weight or less of the entire resin composition. More preferably, it is 25% by weight or more and 35% by weight or less. In addition, when the hardening rate control agent contained in this resin composition and the liquid thickener which is another component are polyorganosiloxane, it shall be contained in content of said (A).
The content of the (B) white pigment in the thermosetting silicone resin composition is not limited as long as the resin composition can be used as a resin molding material as described above. It is 30 to 85 weight% of the whole, Preferably it is 40 to 80 weight%, More preferably, it is 45 to 70 weight%.
The content of the fluidity modifier in the thermosetting silicone resin composition is not limited as long as it does not impair the effects of the present invention, but is usually 55% by weight or less, preferably 2% by weight of the total resin composition. % To 50% by weight, more preferably 5% to 45% by weight.

<4. Components other than packages>
Hereinafter, components other than the package in the semiconductor light emitting device of the present invention will be described with reference to FIG.

<4.1. Semiconductor light emitting device>
As the light emitting element 3, a near ultraviolet semiconductor light emitting element that emits light having a wavelength in the near ultraviolet region, a purple semiconductor light emitting element that emits light in a purple region, a blue semiconductor light emitting element that emits light in a blue region, or the like is used. In general, these light-emitting elements emit light having a wavelength of 350 nm to 520 nm.

Specifically, the light emitting element 3 is formed by forming a semiconductor such as GaAlN, ZnS, ZnSe, SiC, GaP, GaAlAs, AlN, InN, AlInGaP, InGaN, GaN, and AlInGaN on the substrate as a light emitting layer.
Examples of the semiconductor structure include a homo structure having a MIS junction, a PIN junction, and a PN junction, a hetero structure, and a double hetero structure. Various emission wavelengths can be selected from ultraviolet light to infrared light depending on the material of the semiconductor layer and the degree of mixed crystal. The light emitting layer may have a single quantum well structure or a multiple quantum well structure formed as a thin film in which a quantum effect is generated.

  When considering use outdoors, it is preferable to use a gallium nitride compound semiconductor as a semiconductor material capable of forming the high-luminance light-emitting element 3, and in red, a gallium-aluminum-arsenic semiconductor or aluminum-indium- Although it is preferable to use a gallium / phosphorus-based semiconductor, various semiconductors can be used depending on the application.

When a gallium nitride compound semiconductor is used, a material such as sapphire, spinel, SiC, Si, ZnO or GaN single crystal is used for the semiconductor substrate. In order to form gallium nitride with good crystallinity with high productivity, it is preferable to use a sapphire substrate.
Gallium nitride-based compound semiconductors exhibit N-type conductivity without being doped with impurities. When forming a desired N-type gallium nitride semiconductor such as improving luminous efficiency, Si, Ge, Se, Te, C, etc. are preferably introduced as appropriate as N-type dopants.

  On the other hand, when a P-type gallium nitride semiconductor is formed, a P-type dopant such as Zn, Mg, Be, Ca, Sr, or Ba is doped. Since a gallium nitride based semiconductor is difficult to be converted into a P-type simply by doping with a P-type dopant, it is necessary to make it P-type by annealing it by heating in a furnace, low electron beam irradiation, plasma irradiation or the like after introducing the P-type dopant. The semiconductor wafer thus formed is partially etched to form positive and negative electrodes. After that, the light emitting element can be formed by cutting the semiconductor wafer into a desired size.

A plurality of such light emitting elements 3 can be used as necessary, and the color rendering property in white display can be improved by the combination thereof.
In order to improve the luminous efficiency, a metal reflective film is provided directly under the light emitting layer by vapor deposition, etc., and the substrate such as sapphire is peeled and removed, and the rear surface metal reflection is replaced with a new support substrate such as Ge or Si. A light-emitting element with a layer can also be used.

<4.2. Sealing material>
The sealing material 4 is inserted into a recess formed by the circuit board 10 and the wall portion 20 in the package 2 on which the light emitting element 3 is placed, thereby covering the light emitting element 3.
The sealing material 4 protects the light emitting element 3 from external force, dust, moisture, and the like from the external environment, and enables the light emitted from the light emitting element 3 to be efficiently emitted to the outside.
Further, since the refractive index of the light emitting element 3 and the refractive index of air are greatly different, the light emitted from the light emitting element 3 is not efficiently output to the outside, but the light emitting element 3 is covered with the sealing material 4. By doing so, the light emitted from the light emitting element 3 can be efficiently output to the outside. Further, a part of the light emitted from the light emitting element 3 is irradiated to the bottom surface 10a and the side surface 20b of the recess, reflected, and emitted to the main surface side on which the light emitting element 3 is placed. Thereby, the light emission output on the main surface side can be improved.

  It is preferable to use a thermosetting resin composition as the resin composition for a sealing material constituting the sealing material 4. Accordingly, the thermosetting silicone resin composition constituting the resin molding in the resin package for semiconductor light emitting device and the thermosetting resin composition for sealing material constituting the sealing material are respectively thermosetting resins. Therefore, since the physical properties such as the chemical properties and the expansion coefficient are similar, the adhesiveness is good, and peeling at the interface between the resin molded body and the sealing material can be prevented.

The thermosetting resin as the main component of the sealing material is a resin that is excellent in transparency, light resistance, and heat resistance, and can seal a semiconductor light emitting device without cracking or peeling even after long-term use. Used.
Examples of the thermosetting resin include an epoxy resin, a modified epoxy resin, a silicone resin, a modified silicone resin, an acrylate resin, and a urethane resin, and one or more of them can be used. Among these, epoxy resins, modified epoxy resins, silicone resins, and modified silicone resins are preferable in terms of transparency, electrical insulation, and chemical stability. Particularly, silicone resins and modified silicone resins are excellent in light resistance and heat resistance. Since it is the same kind of resin as the resin molding, it is excellent in adhesion and is preferably used.
The sealing material 4 is preferably a hard material to protect the light emitting element 3. The sealing material 4 can be mixed with at least one selected from the group consisting of a filler, a diffusing agent, a pigment, a phosphor, and a reflective substance in order to have a desired function. As the diffusing agent that can be used here, barium titanate, titanium oxide, aluminum oxide, silicon oxide and the like are preferable. In addition, organic or inorganic dyes or pigments can be included for the purpose of cutting light with an undesired wavelength. Furthermore, it is also preferable that the sealing material 4 contains one or more phosphors that convert the wavelength of light from the light emitting element 3.
Moreover, the sealing material 4 may contain the ultraviolet absorber and antioxidant other than said adjuvant.

<4.3. Phosphor>
A composition of a phosphor and a sealing material, which will be described below, is injected into a concave portion of the package and molded, or applied to a suitable transparent support on a thin film to be used as a wavelength conversion member. be able to.
The phosphor is not particularly limited as long as it is a substance that is directly or indirectly excited by the light emitted from the semiconductor light-emitting element and emits light of a different wavelength. Even if it is an inorganic phosphor, an organic phosphor Can be used. For example, one or more of blue phosphor, green phosphor, yellow phosphor, orange to red phosphor as exemplified below can be used. It is preferable to appropriately adjust the type and content of the phosphor used so that a desired emission color can be obtained.

<4.3.1. Blue phosphor>
As the blue phosphor, those having an emission peak wavelength of usually 420 nm or more, particularly 430 nm or more, more preferably 440 nm or more, and usually 490 nm or less, especially 480 nm or less, and further 470 nm or less are preferable.
Specifically, (Ca, Sr, Ba) MgAl ₁₀ O ₁₇ : Eu, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ (Cl, F) ₂ : Eu, (Ba, Ca, Mg, Sr) ₂ SiO ₄ : Eu, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ (Cl, F) ₂ : Eu, (Ba, Ca, Sr) ₃ MgSi ₂ O ₈ : Eu are preferred, Ba, Sr) MgAl ₁₀ O ₁₇ : Eu, (Ca, Sr, Ba) ₁₀ (PO ₄ ) ₆ (Cl, F) ₂ : Eu, Ba ₃ MgSi ₂ O ₈ : Eu are more preferable.

<4.3.2. Green phosphor>
The green phosphor preferably has an emission peak wavelength in the range of usually 500 nm or more, particularly 510 nm or more, more preferably 515 nm or more, and usually 550 nm or less, especially 542 nm or less, and even 535 nm or less.
Specifically, Y ₃ (Al, Ga) ₅ O ₁₂ : Ce, CaSc ₂ O ₄ : Ce, Ca ₃ (Sc, Mg) ₂ Si ₃ O ₁₂ : Ce, (Sr, Ba) ₂ SiO ₄ : Eu Β-type sialon, (Ba, Sr) ₃ Si ₆ O ₁₂ : N ₂ : Eu, SrGa ₂ S ₄ : Eu, BaMgAl ₁₀ O ₁₇ : Eu, Mn are preferable.

<4.3.3. Yellow phosphor>
As the yellow phosphor, those having an emission peak wavelength of usually 530 nm or more, particularly 540 nm or more, more preferably 550 nm or more, and usually 620 nm or less, especially 600 nm or less, further 580 nm or less are suitable.
The yellow _{phosphor, Y 3 Al 5 O 12:} Ce, (Y, Gd) 3 Al 5 O 12: Ce, (Sr, Ca, Ba, Mg) 2 SiO 4: Eu, (Ca, Sr) Si 2 N ₂ O ₂ : Eu, (La, Y, Gd, Lu) ₃ (Si, Ge) ₆ N ₁₁ : Ce are preferable.

<4.3.4. Orange to red phosphor>
As the orange to red phosphor, those having an emission peak wavelength in the range of usually 570 nm or more, particularly 580 nm or more, more preferably 585 nm or more, and usually 780 nm or less, particularly 700 nm or less, further 680 nm or less are preferable.
Specifically, (Ca, Sr, Ba) ₂ Si ₅ (N, O) ₈ : Eu, (Ca, Sr, Ba) Si (N, O) ₂ : Eu, (Ca, Sr, Ba) AlSi ( N, O) ₃ : Eu, (Sr, Ba) ₃ SiO ₅ : Eu, (Ca, Sr) S: Eu, (La, Y) ₂ O ₂ S: Eu, Eu (dibenzoylmethane) ₃ . Β-diketone Eu complex such as 10-phenanthroline complex, carboxylic acid Eu complex, K ₂ SiF ₆ : Mn is preferred, (Ca, Sr, Ba) ₂ Si ₅ (N, O) ₈ : Eu, (Sr, Ca) AlSi (N, O): Eu, (La, Y) ₂ O ₂ S: Eu, and K ₂ SiF ₆ : Mn are more preferable.
As the orange phosphor, (Sr, Ba) ₃ SiO ₅ : Eu, (Sr, Ba) ₂ SiO ₄ : Eu, (Ca, Sr, Ba) ₂ Si ₅ (N, O) ₈ : Eu, ( Ca, Sr, Ba) AlSi (N, O) ₃ : Ce is preferred.

<4.4. Protective element>
The semiconductor light emitting device 1 may further be provided with a Zener diode as a protective element. The zener diode can be mounted on the circuit board 10 as with the light emitting element 3.

<4.5. Heat sink (external heat dissipation member)>
A heat sink can be provided on the back side of the semiconductor light emitting device 1 via a heat radiation adhesive. This heat radiation adhesive preferably has high thermal conductivity. As the material of the heat radiation adhesive, an electrically insulating epoxy resin, silicone resin, or the like can be used. The material of the heat sink is preferably aluminum, copper, tungsten, gold or the like having good thermal conductivity.

  By adopting the above configuration, a semiconductor light emitting device according to the present invention can be provided.

<5. Mounting state of semiconductor light emitting device>
A mounting state in which the semiconductor light emitting device is electrically connected to an external electrode is shown. FIG. 2 is a schematic cross-sectional view showing a mounted state of the semiconductor light emitting device 1 which is one embodiment of the present invention.

In FIG. 2, the semiconductor light emitting device 1 is placed on a circuit board 50 that is a metal base. The circuit board 50 includes printed wiring portions 51 and 52 formed on a base substrate 53 in which an insulating layer 53b is formed on a metal substrate 53a containing a metal such as aluminum or copper. The semiconductor light emitting device 1 is placed on the exposed portion. In FIG. 2, a metal base substrate has been described as an example of the circuit substrate 50, but the material of the base substrate 53, which is the base of the circuit substrate 50, may be other insulating glass epoxy substrates, polybutylene terephthalate (PBT) resin substrates. A group consisting of a polyimide substrate, an aluminum nitride substrate, a boron nitride substrate, a silicon nitride substrate, an alumina ceramic substrate, a silicon carbide substrate, a glass substrate, a flexible glass substrate, an aluminum substrate having an insulating resin layer, and / or a hybrid substrate comprising a copper substrate It may be formed of at least one selected from The resin portion 54 is preferably made of a white solder resist having a high reflectance with respect to the light emitted from the semiconductor light emitting device 1 and may be formed using a liquid thermosetting silicone composition having the same composition as the reflector of the present invention. .
The semiconductor light emitting device 1 is fixed to the printed wiring portions 51 and 52 of the circuit board 50 with solder 55 and is electrically connected to the external electrodes.
2 shows a state in which one semiconductor light emitting device 1 is mounted on the exposed portion of the circuit board 50, the circuit substrate 50 has a plurality of similar exposed portions, each of which has a semiconductor light emitting device. 1 can also be implemented.

  FIG. 3 is another schematic cross-sectional view showing a mounted state of the semiconductor light emitting device 1A which is one embodiment of the present invention.

In FIG. 3, the semiconductor light emitting device 1 </ b> A is formed integrally with a circuit board 50 that is a metal base, and the inside is a semiconductor light emitting device portion 1 </ b> A from the portion where the reflector is bonded. The circuit board 50 includes printed wiring portions 51 and 52 formed on a base substrate 53 in which an insulating layer 53b is formed on a metal substrate 53a including a metal such as aluminum or copper. The resin portion 54 is covered so as to be partially exposed, and the semiconductor light emitting element 1 is placed on the exposed portion.
In this figure, the circuit board 50 is a metal base board, but the material of the base board may be other materials as in the circuit board of FIG. The resin portion 54 is preferably made of a white solder resist having a high reflectance with respect to the light emitted from the semiconductor light emitting device 1A, and may be formed using a liquid thermosetting silicone composition having the same composition as the reflector of the present invention. Good.
In this embodiment, since the heat generated by the light emitting element 1 is directly transmitted to the circuit board, the heat radiation is better than that in the embodiment of FIG. The material of the base substrate may be a metal base substrate such as aluminum or copper having high thermal conductivity, a ceramic substrate such as an aluminum nitride substrate, a boron nitride substrate, a silicon nitride substrate, an alumina ceramic substrate, or a silicon carbide substrate. If a base having a better heat dissipation than the base substrate is provided directly below, the above high heat dissipation characteristic is further utilized, and a semiconductor light emitting device with high brightness and long life can be obtained.
In this embodiment, since the semiconductor light emitting device portion 1A is provided on a part of a wide circuit board, if the reflector is integrally formed with the circuit board, a large mold is required and productivity is low. If the retroreflector of the present invention is bonded, only the reflector can be mass-produced and bonded to an arbitrary position on the circuit board. Therefore, this embodiment also has an advantage of high productivity and high design freedom such as design change.
3 shows a state in which one semiconductor light emitting device 1A is mounted on an exposed portion of the circuit board 50, the circuit board 50 has a plurality of similar exposed portions, each of which has a semiconductor light emitting device. 1A can also be implemented.

<6. Manufacturing Method of Retrofit Reflector and Resin Package for Semiconductor Light Emitting Device>
The manufacturing method by the liquid injection molding of the retrofit reflector for semiconductor light-emitting devices of this invention and the resin package for semiconductor light-emitting devices is demonstrated.
4A to 4F are schematic cross-sectional views illustrating manufacturing steps of the semiconductor light emitting device according to the embodiment of FIG.

  First, as a first step, a space for injecting a liquid thermosetting silicone resin corresponding to a reflector is formed by the first mold 100 and the second mold 110 (FIGS. 4A and 4B). ). In the first mold 100, a recess 100b corresponding to the shape of the reflector 2 is formed.

  Next, as the second step, the liquid thermosetting silicone resin composition described above is injected into the space formed by the recesses of the first mold 100 and the second mold 110 using an injection molding machine. Molding is performed (FIG. 4C).

  In this step, the liquid thermosetting silicone resin composition is supplied by a method such as pressure feeding from a predetermined container such as a pail can. The thermosetting silicone resin composition is either a one-pack type or a two-pack type, and once the composition is pumped to a metering plunger or metering screw part using a pail pump (drum pump), then a preheated mold A predetermined amount is injected from the measuring plunger (or measuring screw). In the case of the two-component type, the two components are measured simultaneously by a method in which two single-component pail pumps (drum pumps) are coaxially operated and the plunger is operated simultaneously, or by a method linked and operated by a hydraulic mechanism. Then, it may be injected from the measuring plunger (or measuring screw) via the mixing device. In order to reduce measurement errors, the two components are preferably close to a volume ratio of 1: 1, and in order to mix uniformly, the respective viscosities are preferably set to the same level.

Here, the injection molding pressure in the second step is preferably 10 to 1200 kg / cm ² . In the injection molding pressure is less than 10 kg / cm ^2, slow flow in the mold of the liquid curable composition, curing may cause unfilled (short) occurs prior, exceeds 1200 kg / cm ² There is a possibility that the flow of the liquid curable composition is too fast and filling unevenness in which the thin portion or the like is unfilled occurs, or the molded product expands due to residual stress, resulting in poor mold release.
Furthermore, the cylinder temperature of the liquid injection molding machine is preferably 0 ° C to 100 ° C. If the cylinder temperature is less than 0 ° C., the condensed water may be mixed into the liquid thermosetting composition and may be frozen and cannot be removed. If the temperature exceeds 100 ° C., the curing reaction of the liquid thermosetting composition proceeds excessively, There is a possibility of thickening.

  Next, as a third step, the reflector 2 is obtained by curing the thermosetting silicone resin composition injected and injected by heating the first mold 100 and the second mold 110. . The obtained reflector 2 is taken out from the mold and then separated into individual pieces, which are provided to a semiconductor light emitting device described later.

From the viewpoint of reducing burrs and short molds and improving mold release, the conditions such as the temperature and time of the heating / curing process are 120 ° C. to 230 ° C. and 3 ° C., respectively. It is preferable that it is for 10 seconds. You may post-cure as needed.
If the curing temperature at the time of liquid injection molding is higher than this range, there is a possibility of causing degradation of the resin and unfilling due to the too high curing rate. On the other hand, when the curing temperature is lower than this range, it takes a long time to cure and the productivity may be lowered, or the mold release may be deteriorated due to insufficient curing. The curing time may be appropriately selected according to the gelation rate and curing rate of the thermosetting silicone resin composition, but is preferably 3 seconds to 10 minutes, more preferably 5 seconds to 200 seconds, and still more preferably Is 10 seconds or more and 60 seconds or less. If the curing time is shorter than the above range, insufficient curing may occur and mold release may deteriorate. Further, if the curing time is longer than the above range, the productivity is lowered and the advantages of liquid injection molding cannot be utilized.

  Next, as a fourth step, the reflector 2 obtained as described above is attached to the circuit board 10 having the first printed wiring portion 11 and the second printed wiring portion 12 via the adhesive layer 30 (FIG. 4 (d)). As the adhesive, a modified silicone resin is preferably used.

Next, as a fifth step, the light emitting element 3 is placed on the first printed wiring portion 11 of the circuit board 10, and the first electrode 3a and the second electrode 3b that the light emitting element 3 has via the wires 5a and 5b. Are electrically connected to the first printed wiring section 11 and the second printed wiring section 12, respectively. This electrical connection may be made either before or after the reflector is attached to the circuit board, but is usually made after the attachment.
Through the above steps, a package having the shape of FIG. If necessary, the circuit board 10 may be cut into pieces by dicing or the like before or after placing the light emitting element 3 as shown in FIG. 4 (f).

  In the case where the light emitting element 3 has electrodes on the upper surface and the lower surface, the first electrode 3a on the lower surface of the light emitting element 3 may be electrically connected by die bonding without using a wire. Here, when the protective element is placed on the first printed wiring portion 11 and the second printed wiring portion 12, the placing step may be performed before or after the fifth step.

  Next, as a sixth step, a thermosetting resin composition for a sealing material is inserted into a recess formed by the circuit board 10 on which the light emitting element 3 is placed and the wall portion 20 of the reflector 2.

  The thermosetting resin composition for a sealing material can be charged by a dropping method, an injection method, an extrusion method, or the like, preferably by a dropping method. This is because the air remaining in the recess can be efficiently discharged by dropping. When it is necessary to convert the light emission wavelength of a light emitting element such as a white LED, the thermosetting resin composition for a sealing material preferably contains a phosphor. Thereby, the color tone adjustment of the semiconductor light emitting device can be facilitated.

  Next, as a seventh step, the sealing material 4 is molded by heating and curing the thermosetting resin composition for the sealing material (FIG. 4F).

  By such a procedure, a semiconductor light emitting device excellent in heat resistance, light resistance, adhesion and the like can be manufactured with high productivity. In particular, the thermosetting silicone resin composition that is the material of the wall portion 20 and the thermosetting resin composition for sealing material that is the material of the sealing material 4 are both based on the thermosetting resin. Therefore, it is possible to provide a semiconductor light emitting device that is excellent in heat resistance, hardly peels off at the interface between the wall portion 20 and the sealing material 4 and is excellent in heat resistance, light resistance, adhesion, and the like.

<7. Discrete method and mounting method of retroreflector>
The reflector of the present invention can be molded by individual molding that has been conventionally performed. However, even when a plurality of reflectors connected to each other is molded, it is possible to make a cut or place a thin portion at a planned cutting location. By simply pulling, it can be easily cut and separated.
Hereinafter, a case where the reflector is molded by a method in which a plurality of reflectors are integrally formed on a plane and a sheet-like reflector molded body having a precut line between the reflectors will be described. The sheet-shaped reflector molded body can be easily divided into pieces and aligned as follows, and a reflector suitable for automatic mounting can be provided.

FIG. 5 is a conceptual diagram (perspective view) of a sheet-shaped reflector molded body 200 in which the reflector of the present invention is molded into a sheet shape. The sheet-like reflector molded body 200 is a perforated sheet in which the reflectors before being singulated are connected, and has a shape in which a plurality of reflectors are connected in a planar shape via a precut line. The precut line 201 is formed at the time of molding.
Such a molded body becomes runnerless molding, and the yield of the molding resin composition is increased, so that a package can be produced at low cost.

FIG. 6 is an enlarged view of a part of the sheet-like reflector molded body 200 shown in FIG. FIG. 6A is a perspective view thereof, and FIG. 6B is a plan view thereof. As can be seen from the drawing, the sheet-like reflector molded body is formed by the connecting surface 202 in which the reflector before separation is left on the precut line. The liquid thermosetting silicone resin composition of the present invention is excellent in resin flowability at the time of molding, and has a characteristic that can be molded without short-circuiting the resin via a thin connecting portion (connecting surface 202).
The sheet-like reflector molded body 200 has a structure in which wall portions corresponding to individual reflectors are connected by a connecting surface below a lower precut line (a cut or thin portion provided for singulation). Each reflector has an opening penetrating vertically corresponding to the package recess, and the opening becomes wider toward the upper surface, and the outside of the wall portion of each reflector may be perpendicular to the connecting surface of the sheets. It is preferable to have a tapered (inclined) shape whose thickness decreases toward the end. As a result, the light extraction efficiency of the semiconductor light emitting device obtained is improved, and the mold releasability during liquid injection molding is improved. The resin composition for a molded body is introduced into the mold from the connecting surface side of the sheet-like reflector molded body, and reaches or fills each reflector portion through the connecting surface. The molded body resin material of the present invention has a good flow even in a narrow space, and can spread the resin over the entire sheet without a short circuit through the connecting surface.
The connection surface is provided with a shallow cut or thin portion as shown in the drawing as required.
The sheet-shaped reflector molded body made of the resin composition molded body of the present invention has the advantage that it can be easily separated into individual pieces from the planned cutting site by pulling, and does not require an expensive dedicated jig such as a dicer. In addition, there is a characteristic that there is no generation of dust and debris during cutting, and the cut surface is smooth.

  FIGS. 7A to 7D show one mode for separating and aligning the reflectors from the sheet-like reflector molded body 200. FIG.

  First, as a first step, a sheet-like reflector as shown in FIG. 5 is formed by liquid injection molding. The sheet-like reflector is formed with the aforementioned precut line and an opening penetrating vertically (FIG. 7A).

  Next, as a second step, the sheet-shaped reflector molded body is attached to a resin sheet (expanded sheet) having flexibility and elongation properties via a sticky adhesive (FIG. 7B).

  As a third step, by pulling the sheet vertically and horizontally, the sheet-shaped reflector molded body is separated by a pre-cut line and separated into pieces in an aligned state. (FIG. 7 (c)).

  As a fourth step, the aligned reflector is automatically picked up by an image recognition device, conveyed to a predetermined position of the COB wiring board by an adsorption collet or the like, and pasted to a predetermined position of the wiring board via an adhesive (FIG. 7). (D)).

  The base material of the expanded sheet is preferably a film having elongation characteristics such as polyvinyl chloride, polyethylene terephthalate, and unstretched polyolefin. The adhesive adhesive layer for attaching the reflector on the expanded sheet may be applied on the expanded sheet or on the back surface of the sheet-like reflector, but the separated reflector is picked up from the expanded sheet. In some cases, it is preferably present on the back surface of the reflector and behaves as a thermosetting adhesive when the reflector is placed on the wiring board and bonded.

  Since the reflector of the present invention is a silicone resin composition, the adhesive adhesive is preferably a composition mainly composed of a modified silicone resin having excellent adhesion to the silicone resin and high temperature durability. In order to develop adhesiveness, silicone raw rubber (dimethylsilicone having a molecular weight of several hundreds of thousands or more) and MQ resin having an M / Q ratio of 0.7 to 1.0 (M: 1 functional silicon unit, Q: A component referred to as a partially crosslinked silicone polymer comprising tetrafunctional silicon units. The adhesive functional group of the modified silicone resin may appropriately have an adhesive group such as an epoxy group, an acrylic group, a methacryl group, an isocyanuric group, an alkoxy group, or a hydroxyl group in order to adjust the adhesive force. In the case of having a condensable functional group such as a hydroxyl group or an alkoxy group, a minute amount of a condensation catalyst may be added. The curing mechanism of the adhesive adhesive when bonding the reflector and the wiring board is preferably a thermosetting type, especially a peroxide curing type that is less susceptible to catalyst poisoning and an addition curing type that can be rapidly cured with less detaching components. preferable. A plurality of curing mechanisms may coexist. Since the peroxide curing type requires a slightly higher temperature and time for curing than the addition curing type, the addition curing type is preferable when the wiring substrate to be bonded is a resin base material. The surface of the expanded sheet may have a release agent layer as necessary in order to facilitate peeling at the time of pickup.

In addition to the adhesive adhesive that fixes the reflector on the expand sheet, an adhesive that adheres the reflector can be applied to the wiring board. In this case, in order to facilitate the individualized reflector pickup from the expanded sheet, the adhesive may be a UV curable acrylic silicone that can reduce the adhesiveness by irradiation with ultraviolet rays.
Each of the adhesive layers may be provided by coating, but may be disposed at a predetermined position in the form of a double-sided tape or the like.

  Conventional reflectors molded with a resin composition for molded bodies have been difficult to separate and align, but can be easily separated and aligned by the above method. In the present invention, the singulated reflector before adhering to the wiring board may be provided to the user in a state of being aligned with the expanded sheet, or may be provided as a tape reel.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to a following example, unless the summary is changed.

As Example 1, a thermosetting silicone resin composition using a liquid thermosetting polyorganosiloxane (1), which will be described later, is used as a resin for a molded resin constituting the wall portion, and is compatible with a resin package for a semiconductor light emitting device. Each test piece was molded to perform the evaluation.
In addition, as Comparative Example 1, a commercially available package and test piece manufactured using Amodel A4122 manufactured by Solvay Advanced Polymers Co., Ltd., which is a polyphthalamide resin composition (containing a titania pigment and glass fiber), were used. .
Further, as Comparative Example 2, a commercially available package and a test piece, which are a highly crosslinked silicone resin composition (containing a titania pigment and spherical silica), were used.
The physical properties of each material and the obtained composition were measured, and the reflectance was compared using each test piece.

[1. Production of liquid thermosetting polyorganosiloxane (1)]
Vinyl group-containing polydimethylsiloxane composition (vinyl group: 0.3 mmol / g contained, viscosity 3500 mPa · s, platinum complex catalyst 8 ppm contained) and hydrosilyl group-containing polydimethylsiloxane composition (vinyl group: 0.1 mmol / g contained) , Hydrosilyl group: 4.6 mmol / g contained, viscosity: 600 mPa · s) and polydimethylsiloxane (vinyl group: 0.2 mmol / g contained, hydrosilyl group: 0. Liquid thermosetting polyorganosiloxane containing 1 mmol / g, alkynyl group: 0.2 mmol / g, 500 mPa · s) at a ratio of 100: 10: 5 and containing (C) a platinum concentration of 7 ppm as a curing catalyst. (1) was obtained.
The liquid thermosetting polyorganosiloxane (1) had a refractive index of 1.41.

[2. Preparation of resin molding material, production of reflectance measurement specimen]
<Example 1>
(A) 60 parts by weight of liquid thermosetting polyorganosiloxane (1) obtained at room temperature (25 ° C.) obtained above, (B) primary particle diameter of 0.3 μm as white pigment, central particle diameter D of secondary particles ₅₀ 35 parts by weight of α-crystal-form crushed alumina having an aspect ratio of 1.48 (E) Silica fine particles having a primary particle size of 12 nm as a fluidity modifier (specific surface area 140 m ² / g, trimethylsilyl group surface treatment) Was mixed at a ratio of 5 parts by weight, and the white pigment and the silica fine particles were dispersed in the above (1) by stirring using a rotation and revolution mixer to obtain a white resin molded material. These materials were cured by a hot press machine at 180 ° C., 10 kg / cm ² , and a curing time of 240 seconds, and a circular test piece (test piece) of Example 1 having a diameter of 13 mm and a thickness of 0.4 mm was obtained. Obtained.
<Comparative Example 1>
About the polyphthalamide resin of the comparative example 1, what cut out the 2 mm thickness test panel of Amodel A4122 by Solvay Advanced Polymers Co., Ltd. to the magnitude | size of about 10 square mm was made into the test piece (test piece).
<Comparative example 2>
Regarding the highly crosslinked silicone resin that is solid at room temperature (25 ° C.) in Comparative Example 2, 44 parts by weight of a condensation-curable silanol-containing methylsilicone resin having a ratio of bifunctional silicon units: trifunctional silicon units of 1: 3 42 parts by weight of spherical silica having a diameter of μm to 100 μm, 13 parts by weight of titania having an average particle diameter of 0.4 μm as a white pigment, and a catalytic amount of aluminum triacetylacetonate are dispersed by a rotating and rotating mixer, and used for a white resin molding Obtained material. This material was cured by a transfer molding machine under the conditions of 175 ° C., 70 kg / cm ² and a molding time of 180 seconds to obtain a test piece having a thickness of 550 μm and a 10 mm square.

[3. Measuring method of primary particle diameter of white pigment and aspect ratio of primary particles]
The primary particle diameter was measured by SEM observation of the white pigment (alumina powder) used in the examples. When there was variation in the particle diameter, several points (for example, 10 points) were observed with an SEM, and the average value was obtained as the particle diameter. In particular, when the difference between the small particle size and the large particle size is about 5 times or more except for fine particles and coarse particles contained in a very small amount, the maximum and minimum values are recorded. The major axis length (maximum major axis) and minor axis length (the length of the longest part perpendicular to the major axis) are also measured, and the major axis length is adopted as the primary particle diameter. The value obtained by dividing (maximum major axis) by the minor axis length (the length of the longest portion perpendicular to the major axis) was taken as the aspect ratio.

[4. Method of measuring the mean particle diameter D ₅₀ of the white pigment secondary particles]
10 g of 0.2% sodium polyphosphate aqueous solution was added to 10 to 20 mg of white pigment (alumina powder), and alumina was dispersed by ultrasonic vibration. Using this dispersion, the volume-based center particle diameter D ₅₀ of the secondary particles of the white pigment was measured with a Microtrac MT3000II manufactured by Nikkiso Co., Ltd. The central particle size D ₅₀ is the particle size at the point where the volume-based particle size distribution curve of cumulative% intersects the horizontal axis of 50%.

[5. Specimen reflectance measurement]
About each test piece of the said Example 1 and the comparative example 1, the reflectance in the wavelength of 360 nm to 740 nm was measured with the measurement diameter of 6 mm using SPECTROTOPOMETER CM-2600d by Konica Minolta. The measurement results are shown in Table 1 together with the reflectance value of the metal material for printed wiring (silver plating). The material for a resin molded body of the present invention includes a conventional resin material such as a polyphthalamide resin or a silicone resin that uses only titania as a reflective material, and a resin and a reflective material that are used as a binder rather than silver plating that is frequently used for LEDs. Since the reflectivity is high due to the type and particle diameter of the filler, it is possible to reduce the exposed area of the electrode on the surface of the silver plating that is likely to be colored and deteriorated during long-term use.
The test piece of Example 1 was cut with a microtome while frozen with liquid nitrogen, and SEM observation of the package cross section was performed. The primary particle diameter of the alumina exposed in the cross section was 0.3 μm, and the aspect ratio of the primary particles was 1.48.

[6. Viscosity measurement of resin molding materials]
About the material for resin moldings of Example 1, viscosity measurement was performed at a measurement temperature of 25 ° C. using a parallel plate in RMS-800 manufactured by Rheometrics.
The results are shown in Table 2. It can be seen that the material of Example 1 is suitable for the liquid injection molding of a resin molded body in terms of the viscosity at a shear rate of 1 s ⁻¹ and 100 s ⁻¹ at 25 ° C. and the inclination thereof.

[7. Liquid injection molding of retroreflector]
The retroreflector for a semiconductor light emitting device can be molded by liquid injection molding using the resin molded body material of Example 1. Molding is performed under conditions of a mold temperature of 170 ° C. and a curing time of 20 seconds.

[8. Shore D hardness measurement]
Each test piece (thickness 3 mm) of the resin molded body 1 is post-cured for 10 minutes or more with a 200 ° C. incubator, and then the two test pieces are stacked, using a rubber / plastic hardness meter KORI Durometer KR-25D. According to JIS K6253, the Shore D hardness near the center of the test piece was measured. The test pieces of Comparative Examples 1 and 2 were similarly measured.

  As shown in Table 3, the sample of Example 1 has a soft property as compared with the conventional resin molding for packaging. The shape of the stressed part was restored without any scratches or scars remaining after the measurement. On the other hand, the sample of Comparative Example 2 was hard but fragile, and the sample was cracked by the hardness measurement.

[9. Individualization test of resin moldings]
A sample similar to the reflectance measurement sample of Example 1, Comparative Example 1 and Comparative Example 2 is prepared, and a straight cut is made with a cutter knife from end to end of the resin molded body sample, and the thickness of the connecting portion is increased. A sample of 0.5 mm was obtained. This sample was subjected to a 90-degree bending and a 180-degree tensile test to determine whether it could be separated into pieces. The results are shown in Table 4.

  As shown in the table, the sample of Example 1 can be easily separated according to the precut line only by pulling, without using a device such as a dicer, as compared with the conventional package molded body of Comparative Example 1 or Comparative Example 2. I was able to. As for Example 1, a sample molded by liquid injection molding could be easily separated into pieces.

[10. Manufacturing of sealing material]
Momentive Performance Materials Japan G.K. both ends silanol dimethyl silicone oil XC96-723 385g, methyltrimethoxysilane 10.28g, and zirconium tetraacetylacetonate powder 0.791g as a catalyst, , Weighed into a 500 ml three-necked flask equipped with a fractionating tube, Dimroth condenser and Liebig condenser, and stirred at room temperature for 15 minutes until the coarse particles of the catalyst were dissolved. Thereafter, the temperature of the reaction solution was raised to 100 ° C. to completely dissolve the catalyst, and initial hydrolysis was performed while stirring at 500 rpm for 30 minutes under 100 ° C. total reflux using a Dimroth condenser.

Subsequently, the distillation line was switched to the Liebig condenser side, nitrogen was blown into the liquid with SV20, and methanol, water, and by-product low-boiling silicon compounds were distilled off accompanied by nitrogen at 100 ° C. and 500 rpm. Stir for hours. The polymerization reaction was continued for 5 hours while raising and maintaining the temperature at 130 ° C. while blowing nitrogen into the liquid with SV20 to obtain a reaction liquid having a viscosity of 120 mPa · s. “SV” is an abbreviation for “Space Velocity” and refers to a nitrogen blowing volume ratio per unit time (vs. reaction solution volume).
Nitrogen blowing was stopped and the reaction solution was once cooled to room temperature. Then, the reaction solution was transferred to an eggplant-shaped flask, and a methanol remaining in a minute amount at 120 ° C. and a pressure of 1 kPa on an oil bath using a rotary evaporator. Water and a low-boiling silicon compound were distilled off to obtain a solvent-free sealing material liquid having a viscosity of 230 mPa · s and a refractive index of 1.41.

[11. Manufacturing of light-emitting device]
[11-1. Assembly of light emitting device]
The individualized reflectors of Example 1 and Comparative Examples 1 and 2 are bonded with an acrylic silicone adhesive to a chip-on-board type wiring board having positive and negative leads on which a light emitting element is mounted. Further, three types of light emitting devices are assembled as follows. Silicone die-bonding material (Shin-Etsu Chemical Co., Ltd.) at a predetermined position on the first printed wiring portion where one semiconductor light emitting element (rated current 20 mA) having emission wavelengths of 360 nm, 406 nm, and 460 nm is exposed in the concave portion of the package. After installation through KER-3000-M2), the silicone die bond material is cured at 100 ° C. for 1 hour and further at 150 ° C. for 2 hours. After the semiconductor light emitting device is mounted on the package in this way, the printed wiring portion of the package and the semiconductor light emitting device are connected with a gold wire.

[11-2. Semiconductor light emitting device sealing]
After dropping the above-described sealing material into the package recess of the light emitting device manufactured in 11-1 so as to be the same height as the upper edge of the opening, the thermostat is 90 ° C. × 2 hours, and then 110 ° C. × Three types of semiconductors having a light emitting element of 360 nm, 406 nm, and 460 nm for each of the packages of Example 1 and Comparative Example 1 are cured by heating and curing for 1 hour at 150 ° C. for 3 hours to transparently seal the semiconductor light emitting element. A light emitting device is obtained.

  According to the present invention, indoor and outdoor lighting fixtures, displays, backlights for mobile phones, liquid crystal televisions, digital signage, etc., in-vehicle lighting such as camera flashlights, headlights, inspection and medical lighting, plant factories A semiconductor light-emitting device that can be suitably used as a light source for various illuminations is provided.

DESCRIPTION OF SYMBOLS 1,1A Semiconductor light-emitting device 2 Reflector 3 Light emitting element 3a 1st electrode 3b 2nd electrode 4 Sealing material 5a, 5b Wire 10 Circuit board 10a Bottom surface (of a recessed part) 11 1st printed wiring part 11a 1st exterior Terminal portion 12 Second printed wiring portion 12a Second external terminal portion 13 Base substrate 20 Wall portion of reflector 20a Side surface of concave portion 20b Side end portion 30 Adhesive layer 50 Circuit board 51, 52 Printed wiring portion 53 (Metal) Base substrate 53a Metal substrate 53b Insulating layer 54 Resin portion 55 Solder 100 First mold 100a Convex portion 100b Concave portion 100c Flat portion 110 Second die 200 Sheet-shaped reflector molded body 201 Precut line 202 Connecting surface 300 Expanding Sheet

Claims (9)

A retroreflector for a semiconductor light emitting device,
The reflector comprises a silicone resin molded body obtained by liquid injection molding a liquid thermosetting silicone resin composition,
A retroreflector for a semiconductor light emitting device, wherein the resin molded body is a resin molded body having a light reflectance of 80% or more measured with a wavelength of 460 nm for a molded body sample having a thickness of 0.4 mm .   2. The retroreflector for a semiconductor light-emitting device according to claim 1, wherein the resin molded body has a Shore D hardness of 30 or more and 80 or less.   The liquid thermosetting silicone resin composition is (A) a polyorganosiloxane, (B) a primary particle having an aspect ratio of 1.2 or more and 4.0 or less, and a primary particle diameter of 0.1 μm or more and 2.0 μm or less. The retroreflector for a semiconductor light-emitting device according to claim 1, wherein the reflector comprises a pigment and (C) a curing catalyst. 4. The viscosity of the liquid thermosetting silicone resin composition at a shear rate of 100 s ⁻¹ at 25 ° C. is in the range of 10 Pa · s to 10,000 Pa · s. 5. The retrofit reflector for semiconductor light-emitting devices of description. It is a manufacturing method of the back reflector for semiconductor light-emitting devices of any one of Claim 1 to 4,
A step of filling a liquid thermosetting silicone resin composition by a liquid injection molding method into a space formed between the first mold and the second mold having a dent corresponding to the reflector;
A step of heating and curing the filled thermosetting silicone resin composition;
The manufacturing method of the retrofit reflector for semiconductor light-emitting devices characterized by having at least. It is a manufacturing method of the back reflector for semiconductor light-emitting devices of any one of Claim 1 to 4,
After obtaining a sheet-like reflector molded body having a shape in which a plurality of reflectors are connected in a planar shape via a precut line by a liquid injection molding method using a liquid thermosetting silicone resin composition, the reflectors are singulated. A method for manufacturing a retroreflector for a semiconductor light emitting device, comprising: a step.   5. A semiconductor comprising the retroreflector for a semiconductor light emitting device according to claim 1 attached to a circuit board on which the semiconductor light emitting element is placed via an adhesive layer. Resin package for light emitting devices.   The resin package for a semiconductor light-emitting device according to claim 7, wherein the adhesive is a modified silicone resin. The resin package for a semiconductor light-emitting device according to claim 7 or 8, a semiconductor light-emitting element, and at least a sealing material that covers the semiconductor light-emitting element,
The semiconductor light emitting device, wherein the semiconductor light emitting element is electrically connected to a circuit board of the resin package for the semiconductor light emitting device.

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