JP2010067641A - Sheet for sealing optical semiconductor element and optical semiconductor device using the same - Google Patents

Abstract

To provide an optical semiconductor element sealing sheet capable of further improving the light extraction efficiency of an optical semiconductor element in an optical semiconductor element sealing sheet capable of easily and reliably sealing an optical semiconductor element, and Provided is an optical semiconductor device in which an optical semiconductor element is sealed by the optical semiconductor element sealing sheet, and the light extraction efficiency of the optical semiconductor element is improved.
An optical semiconductor element sealing sheet comprising at least a release substrate 1, a sealing layer 3 and a light diffusion layer 2, wherein the light diffusion layer is provided on the release substrate, An opening 4 is provided in the light diffusion layer, and the sealing layer is provided in the opening, and an optical semiconductor using the optical semiconductor element sealing sheet and the optical semiconductor element sealing sheet An optical semiconductor device in which an element is sealed.
[Selection] Figure 2

Description

  The present invention relates to an optical semiconductor element sealing sheet and an optical semiconductor device using the same.

  Since the launch of high-intensity blue light-emitting diodes, various products (such as liquid crystal screen backlights, traffic lights, outdoor large displays and advertising billboards) that use optical semiconductor devices mounted with such optical semiconductor elements have been developed. It was. In such product fields, not only product manufacturers but also consumers are strongly committed to quality, so the performance required for optical semiconductor devices is increasing year by year. For example, optical semiconductor device manufacturers are developing more bright elements. It has been continued.

  On the other hand, in order to take advantage of the performance of such a higher-brightness optical semiconductor element, the technology for sealing such an optical semiconductor element is naturally required to be improved. For example, a technique for more easily and reliably sealing an optical semiconductor element and a technique for improving the light extraction efficiency of the element are being actively studied.

  For example, in order to easily and reliably seal an optical semiconductor element, a sheet-like sealing material (optical semiconductor element sealing sheet) has been developed (Patent Document 1).

In such an optical semiconductor element sealing sheet or a conventional optical semiconductor element sealing material, for example, light emitted from the element is scattered by light diffusing particles to improve the light extraction efficiency of the element.
JP 2006-140362 A

  Accordingly, an object of the present invention is to provide an optical semiconductor element sealing sheet that can further improve the light extraction efficiency of the optical semiconductor element in an optical semiconductor element sealing sheet that can easily and reliably seal the optical semiconductor element. It is to provide. Furthermore, the subject of this invention is providing the optical semiconductor device with which the optical extraction efficiency of the optical semiconductor element improved that the optical semiconductor element was sealed with this sheet | seat for optical semiconductor element sealing.

  Therefore, the present inventors have studied various components and blending amounts of resin and light diffusing particles in order to further improve the light extraction efficiency of the optical semiconductor element, and further, encapsulated in an infinite number of combinations. The structure and shape of the stop layer and the light diffusion layer were also examined. As a result, the inventors deliberately removed the light diffusing layer from the sealing layer and the light diffusing layer with a specific structure, specifically the upper portion of the sealing layer, that is, from above the optical semiconductor element. It was found that the light extraction efficiency of the optical semiconductor element can be unexpectedly improved by making the structure surrounding only the side surface of the sealing layer, and the present invention has been completed.

The gist of the present invention is as follows.
[1] An optical semiconductor element sealing sheet comprising at least a release substrate, a sealing layer, and a light diffusion layer,
The light diffusion layer is provided on the release substrate,
The light diffusion layer is provided with an opening, and the sealing layer is provided in the opening.
The present invention relates to an optical semiconductor element sealing sheet, and [2] an optical semiconductor device formed by sealing an optical semiconductor element using the optical semiconductor element sealing sheet described in [1].

  The optical semiconductor element sealing sheet of the present invention can further improve the light extraction efficiency of the manufactured optical semiconductor element by sealing the optical semiconductor element using the sheet. Furthermore, the optical semiconductor device of the present invention is a device in which the light extraction efficiency of the optical semiconductor element is improved, and is useful for various products such as a backlight of a liquid crystal screen, a traffic light, an outdoor large display, and an advertising signboard. Moreover, in the present invention product, a general-purpose product that has been conventionally used in the field of the present invention can be used as the material, which is extremely advantageous in terms of the price and availability of the material.

1) Sheet for optical semiconductor element sealing First, the sheet for optical semiconductor element sealing of the present invention will be described.

The optical semiconductor element sealing sheet of the present invention is an optical semiconductor element sealing sheet comprising at least a release substrate, a sealing layer, and a light diffusion layer,
The light diffusion layer is provided on the release substrate,
The light diffusion layer is provided with an opening, and the sealing layer is provided in the opening.

  The release substrate is a substrate for the optical semiconductor element sealing sheet of the present invention, and a light diffusion layer is formed on the release substrate. Specific examples of the release substrate include polyester films such as polyethylene terephthalate (PET). As a thickness of a mold release base material, the range of 25-50 micrometers is preferable from a workable viewpoint. Since such a mold release substrate may be peeled off when the optical semiconductor element sealing sheet is used or manufactured, it is preferable that the surface of the mold release substrate is subjected to a mold release treatment by a known method.

  The sealing layer is a layer mainly composed of a resin for sealing the optical semiconductor element. The sealing layer is preferably composed of a semi-cured thermosetting resin from the viewpoint of securely sealing the optical semiconductor element. Examples of the thermosetting resin include those conventionally used as the thermosetting resin for the sealing layer in the field of the present invention. Specific examples include silicone resins such as silicone gel and modified silicone resin, Examples thereof include polyborosiloxane resins, polyaluminosiloxane resins, epoxy resins, and acrylic resins, and these resins are preferable from the viewpoint of heat resistance.

  When forming the sealing layer, a fluorescent agent (sialon, YAG, etc.) for adjusting the emission color of the optical semiconductor element (especially a light emitting diode), a resin curing agent (4-methylhexahydrophthalic anhydride, etc.) And other components such as a curing catalyst may be blended as necessary. In addition, the sealing layer may be comprised only by one layer, and may be comprised from several layers.

  As thickness of this sealing layer, 200-1000 micrometers is preferable, 300-800 micrometers is more preferable, 400-600 micrometers is further more preferable. The thickness of the sealing layer is preferably 200 μm or more from the viewpoint of surely sealing, and is preferably 1000 μm or less from the viewpoint of increasing light extraction efficiency.

  Since the sealing layer is provided in an opening provided in the light diffusion layer described later, the shape of the sealing layer corresponds to the shape of the opening. Moreover, it is preferable that the thickness of the sealing layer is the same as the thickness of the light diffusion layer. The shape of the sealing layer is not particularly limited as long as the optical semiconductor element can be reliably sealed and the light extraction efficiency can be improved. As a preferable shape of the sealing layer, the shape of the cut surface (that is, the cut surface parallel to the release substrate when the shape of the sealing layer is regarded as a column) is a circle, an ellipse, a quadrangle, etc. And those having a predetermined thickness. The shape of the cut surface is preferably circular, and the diameter is preferably 2 to 10 mm, more preferably 3 to 8 mm, and even more preferably 4 to 5 mm.

  The number of the sealing layers in the optical semiconductor element sealing sheet of the present invention can be appropriately changed according to the number of optical semiconductor elements on the printed circuit board to be sealed.

  The resin constituting the sealing layer is preferably in a semi-cured state from the viewpoint of workability. Here, the semi-cured state refers to a state where the curing reaction is not completed and plastic deformation is possible.

  In the optical semiconductor element sealing sheet of the present invention, the sealing layer is provided in the opening of the light diffusion layer. That is, in the optical semiconductor element sealing sheet of the present invention, when the release substrate is directed downward, the bottom surface of the sealing layer is in contact with the release substrate, and its side surface is surrounded by the light diffusion layer, The upper part has a unique structure in which there is no light diffusion layer. By adopting such a structure, it is possible to improve the light extraction efficiency from the optical semiconductor element. If necessary, a layer other than the light diffusion layer may be provided on the upper portion of the sealing layer.

  The light diffusion layer in the present invention is a layer mainly composed of light diffusion particles and a resin. Examples of the light diffusing particles contained in the light diffusing layer include those conventionally used as light diffusing particles in the field of the present invention, specifically, barium sulfate, barium oxide, oxidation (such as silicon dioxide). Examples thereof include inorganic particles such as silicon, titanium oxide, silica, zinc oxide, alumina, and zirconium oxide. From the viewpoint of dispersibility and ease of control of particle diameter, barium sulfate and silica are preferred. These light diffusion particles may be used alone or in combination of two or more.

  The range of the particle diameter of the light diffusing particles is preferably 500 nm to 10 μm, and more preferably 500 nm to 5 μm from the viewpoint of maintaining light scattering properties and light transmittance. The particle diameter here is a volume average particle diameter, and can be measured using, for example, Nikkiso Co., Ltd .: Microtrack apparatus.

  The content of the light diffusing particles in the light diffusing layer is preferably larger from the viewpoint of exhibiting light scattering properties, while it is less from the viewpoint of securing light transmittance as a sheet for sealing an optical semiconductor element. Is preferred. The preferred amount of the light diffusing particles depends on the type of the light diffusing particles and the resin to be used, and cannot be generally stated. For example, the amount of the light diffusing particles to be blended in the coating solution described later is appropriately set. Thus, a desired effect can be exhibited.

  As the resin constituting the light diffusion layer, resins conventionally used in the sealing layer in the field of the present invention can be used, and examples thereof include those enumerated as resins that can be used in the above-described sealing layer. . Preferred examples of such resins include silicone resins such as silicone gel and modified silicone resin, polyborosiloxane resins, polyaluminosiloxane resins, and epoxy resins. Here, the type / composition of the resin constituting the light diffusion layer and the resin constituting the sealing layer may be the same or different.

  The thickness of the light diffusion layer is preferably the same as the thickness of the sealing layer.

  The resin constituting the light diffusion layer is preferably in a semi-cured state from the viewpoint of workability. Here, the semi-cured state is the same definition as the semi-cured state defined in the sealing layer.

  In the optical semiconductor element sealing sheet of the present invention, the light diffusion layer is provided on the release substrate, and the light diffusion layer is provided with an opening (provided with a sealing layer). Yes. That is, the light diffusion layer is not provided at a position in direct contact with the optical semiconductor element, and exhibits a predetermined effect through the sealing layer. If necessary, another layer may be provided on the light diffusion layer.

  The sheet for encapsulating an optical semiconductor element of the present invention is “consisting of at least a release substrate, a sealing layer and a light diffusion layer”, wherein “at least the release substrate, the sealing layer and the light. `` Consisting of a diffusion layer '' means a state in which the sealing layer and the light diffusion layer are provided on the release substrate in a state in which the sealing layer and the light diffusion layer can function as an optical semiconductor element sealing sheet, and in addition to these components In addition, it means that another layer or another member may be provided.

  The thickness of the optical semiconductor element sealing sheet of the present invention is preferably 0.4 to 1.0 mm, more preferably 0.4 to 0.6 mm, from the viewpoints of weight reduction / miniaturization and subsequent workability. .

  Next, the sheet | seat for optical semiconductor element sealing of this invention is demonstrated, referring a figure.

  FIG.1 and FIG.2 is a schematic diagram which shows an example of the sheet | seat for optical semiconductor element sealing of this invention. FIG. 1 is a top view of an optical semiconductor element sealing sheet, and FIG. 2 is a cross-sectional view taken along line B-B ′ of FIG. 1. As shown in FIGS. 1 and 2, the optical semiconductor element sealing sheet of the present invention is composed of at least a release substrate 1, a sealing layer 3, and a light diffusion layer 2, and the light diffusion layer 2 is separated. Provided on the mold substrate 1, the light diffusion layer 2 is provided with an opening 4, and the sealing layer 3 is provided within the opening 4. As shown in FIGS. 1 and 2, in the optical semiconductor element sealing sheet of the present invention, the bottom surface of the sealing layer 3 is in contact with the release substrate 1, and the side surface is the light diffusion layer 2. It is surrounded and has a unique structure in which there is no light diffusion layer 2 on the top.

  Next, the manufacturing method of the resin sheet for optical semiconductor element sealing of this invention is demonstrated, referring a figure.

The resin sheet for sealing an optical semiconductor element of the present invention includes, for example, the following steps:
a) a step of forming a light diffusion layer by applying a coating solution on a release substrate;
b) providing an opening in the light diffusion layer; and
c) filling the provided opening with a sealing material composition liquid to form a sealing layer;
It can manufacture by the method containing.

  The formation of the light diffusion layer in step a) can be performed, for example, as follows. First, the resin used for the light diffusing layer, the light diffusing particles, and other components such as a curing agent as necessary are added to an organic solvent such as toluene, cyclohexane, methyl ethyl ketone, and mixed to suspend the light diffusing particles. A prepared liquid (referred to as coating solution) is prepared. Note that the above organic solvent may or may not be used as necessary, and in this specification, a mixture of resin and light diffusion particles obtained without using such a solvent is also referred to as a coating solution.

  Here, the quantitative definition of each component in the coating solution depends on the type of the light diffusing particles and the resin to be used and cannot be generally specified, but for example, the following combinations are preferable. That is, 20 to 100 parts by weight of resin, 20 to 100 parts by weight of light diffusing particles, and 0 to 15 parts by weight of other components such as a curing agent are added to 100 parts by weight of the solvent. More preferably, the resin is 30 to 80 parts by weight, the light diffusion particles are 30 to 80 parts by weight, and other components such as a curing agent are more preferably 0 to 10 parts by weight, and the resin is 50 More preferably, it is -80 parts by weight, 50 to 80 parts by weight of the light diffusing particles, and 0 to 5 parts by weight of other components such as a curing agent. Here, from the viewpoint of exhibiting the light scattering property by the light diffusing particles, it is preferable to mix the light diffusing particles by 20 parts by weight or more with respect to 100 parts by weight of the solvent, and the light transmittance as the sheet for encapsulating the optical semiconductor element. From the viewpoint of ensuring, it is preferable to blend 100 parts by weight or less with respect to 100 parts by weight of the solvent.

  Further, the blending amount of the light diffusing particles when no solvent is used is preferably 10 to 100 parts by weight, more preferably 20 to 80 parts by weight, and 40 to 70 parts by weight with respect to 100 parts by weight of the resin. More preferably, it is a part.

  Examples of the coating solution that can be preferably used in the present invention are: 40 to 50 parts by weight of an epoxy resin having a bisphenol A skeleton having an epoxy equivalent of 7500 and 200 parts by weight of methyl ethyl ketone, and an alicyclic skeleton having an epoxy equivalent of 260. 25 to 40 parts by weight of epoxy resin, 15 to 30 parts by weight of 4-methylhexahydrophthalic anhydride, 0.1 to 0.5 parts by weight of 2-methylimidazole, and a volume average particle size of 4 to 10 μm Examples of the coating solution include 80 to 120 parts by weight of barium sulfate particles.

  Next, the coating solution is preferably applied onto a release substrate such as a PET film whose surface has been release-treated. Specifically, the coating solution can be applied onto the release substrate using a known apparatus (for example, a multi-coater) using casting, spin coating, roll coating, or the like. The coating amount of the coating solution can be adjusted by appropriately setting an apparatus to be used so that the thickness of the light diffusion layer to be formed falls within a predetermined range.

  Next, the coating solution is dried on the release substrate 1 to remove the solvent and form the light diffusion layer 2 (FIG. 3a). The resin constituting the light diffusion layer is preferably in a semi-cured state. The heating temperature or time for bringing the resin into a semi-cured state varies depending on the type of resin and solvent used, and thus cannot be determined unconditionally, but the temperature is preferably 80 to 150 ° C, more preferably 100 to 120 ° C. preferable. Moreover, as time at this time, 1 to 30 minutes are preferable and 3 to 10 minutes are more preferable. The layer thus formed may be used alone as the light diffusion layer, or a layer in which a plurality of layers are stacked may be used as the light diffusion layer 2 (FIG. 3d).

  When using a stack of a plurality of layers as the light diffusion layer 2, a plurality of sheets (for example, three sheets) on which one light diffusion layer 2 as shown in FIG. First, as shown in FIG. 3B, the light diffusion layers 2 are overlapped with each other so as to come into contact with each other, and stacked using a thermal laminator. Next, one mold release substrate 1 is removed (FIG. 3c), and another sheet is superposed on the exposed light diffusion layer 2 so that the light diffusion layers 2 are in contact with each other, and a thermal laminator is used. Laminate (FIG. 3d). In this way, the light diffusion layer 2 in which a plurality of layers as shown in FIG.

  In step b), as a method of providing an opening in the light diffusion layer, for example, a tool such as a punch or a Thomson blade having a desired shape is first formed on a sheet first provided with a light diffusion layer on a release substrate. There is a method in which a through hole is formed using, and then this through hole is used as an opening. In addition, in order to perform subsequent filling operation easily, it is good also considering the shape of an opening part as a blind hole instead of a through-hole by covering one opening | mouth of an opening part with another mold release base material etc.

  For example, when an opening is provided in the light diffusion layer 2 of the sheet shown in FIG. 3d, a through hole 5 is formed in the sheet with a punch (FIG. 4a), and then one mold release substrate 1 is removed (FIG. 4b) and exposed. Further, another release substrate 1 is superposed on the light diffusion layer 2 and laminated using a thermal laminator (FIG. 4c). In this manner, a sheet (FIG. 4c) in which the opening 4 is a blind hole shape can be manufactured. Here, the shape of the opening can be set to a desired shape by appropriately selecting and setting a tool such as a punch. Further, the thickness of the opening can be set to a desired thickness by appropriately adjusting the operation of the tool.

  In step c), a sealing layer is formed. In this step, a liquid material in which a component such as a resin constituting the sealing layer is dissolved or suspended (referred to as a sealing material composition liquid) is prepared, and this opening material is filled with the sealing material composition liquid. The method is preferable because a sealing layer can be easily formed in the opening. In addition to the resin constituting the sealing layer, other components such as a fluorescent agent and a curing agent may be blended in the sealing material composition liquid as necessary.

  The content of such other components in the sealing material composition liquid is, for example, 0 to 30% by weight of the sealing material composition liquid from the viewpoint of facilitating filling operation and exhibiting a predetermined effect. Is preferable, and it is more preferable that it is 5 to 20 weight%.

  As the sealing material composition liquid used in the present invention, a modified silicone resin containing 10 to 15% by weight of a fluorescent agent (sialon) and having a viscosity of 500 to 1000 mPa · s is preferable.

  The opening material is filled with the sealing material composition liquid thus prepared using a device such as a dispenser. The amount of the sealing material composition liquid to be filled can be set to a desired amount by appropriately setting an apparatus to be used, that is, a sealing layer having a preferable thickness can be formed.

  Next, the filled sealing material composition liquid is cured in the opening to form a sealing layer. For example, the book in which the sealing layer 3 is provided in the opening 4 as shown in FIGS. The sheet | seat for optical semiconductor element sealing of invention is manufactured.

  The resin constituting the sealing layer is preferably in a semi-cured state. The heating temperature or time for bringing the resin into a semi-cured state varies depending on the type of resin and solvent used, and thus cannot be determined unconditionally, but the temperature is preferably 80 to 150 ° C, more preferably 100 to 120 ° C. preferable. Moreover, as time at this time, 1 to 30 minutes are preferable and 3 to 10 minutes are more preferable. The layer thus formed may be used alone as the sealing layer, or a layer in which a plurality of layers are stacked may be used as the sealing layer.

2) Optical Semiconductor Device Next, the optical semiconductor device of the present invention will be described.

  The optical semiconductor device of the present invention is obtained by sealing an optical semiconductor element using the optical semiconductor element sealing sheet of the present invention. Examples of the optical semiconductor element used in the present invention include light emitting diodes such as a blue light emitting diode, a green light emitting diode, a red light emitting diode, and an ultraviolet light emitting diode.

  Next, the optical semiconductor device of the present invention will be described with reference to the drawings. 5 and 6 are schematic views showing an example of the optical semiconductor device of the present invention. FIG. 5 is a top view of the optical semiconductor element sealing sheet, and FIG. 6 is a cross-sectional view taken along line A-A ′ of FIG. 5.

  As shown in FIG. 5 and FIG. 6, the optical semiconductor device of the present invention has the optical semiconductor element 11 mounted on the printed circuit board 12 by the sealing layer 3 of the optical semiconductor element sealing sheet of the present invention. The sealing layer 3 has a unique structure in which the side surface of the sealing layer 3 is surrounded by the light diffusing layer 2 and the light diffusing layer 2 is not present on the upper side. With this structure, the light extraction efficiency can be improved.

The optical semiconductor device of the present invention includes, for example, the following steps:
A) a step of laminating the optical semiconductor element sealing resin sheet of the present invention on the surface on which the optical semiconductor element is mounted so that the sealing layer is aligned with the position facing the optical semiconductor element; and
B) Pressurizing and curing the optical semiconductor element sealing resin sheet laminated in step A), and sealing the optical semiconductor element with a sealing layer;
It can manufacture by the method containing.

  In step A), in order to laminate the sealing layer so as to match the sealing layer at a predetermined position, it is not necessary to apply pressure, and the optical semiconductor element sealing resin sheet of the present invention is mounted on the substrate on which the optical semiconductor element is mounted. Just place it on

  In the step B), the pressure-curing condition of the resin sheet for sealing an optical semiconductor element of the present invention is preferably 80 to 150 ° C., more preferably 130 to 150, for example, using a vacuum laminator or a vacuum press machine. The sheet is pressed by pressurizing at a temperature of ° C, and preferably 0.2 to 0.5 MPa, more preferably 0.2 to 0.3 MPa, and then preferably 100 to 150 ° C, more preferably The temperature of 130 to 150 ° C., preferably 1 to 24 hours, more preferably 2 to 5 hours, conditions for post-curing (secondary curing), and the like. Step B) may be performed simultaneously with step A). About a mold release base material, what is necessary is just to peel after this process.

  In this way, the sealing layer of the resin sheet for sealing an optical semiconductor element of the present invention is cured, and the optical semiconductor element is sealed by the sealing layer. Similarly, the resin for sealing an optical semiconductor element of the present invention The light diffusion layer of the sheet is also cured and integrated with the substrate to complete the optical semiconductor device of the present invention.

  Hereinafter, although the aspect of this invention is described in an Example, this invention is not limited to these.

Example 1
45 parts by weight of a bisphenol A skeleton (BFA) epoxy resin having an epoxy equivalent of 7500 (Japan Epoxy Resin Co., Ltd .: EP1256), 33 parts by weight of an epoxy resin having an alicyclic skeleton having an epoxy equivalent of 260 (Daicel Chemical Company: EHPE3150), as a curing agent 4-methylhexahydrophthalic anhydride (22 parts by weight) and 2-methylimidazole (0.2 parts by weight), and barium sulfate particles (volume average particle diameter: 5 μm; Takehara Chemical Industries, Ltd .: W-6) as light diffusion particles 100 Part by weight was dissolved in 200 parts by weight of methyl ethyl ketone to prepare a coating solution for forming a light diffusion layer.

  Next, a light diffusion layer formed using an applicator on a biaxially stretched polyester film (film thickness: 50 μm, Mitsubishi Chemical Polyester Co., Ltd .: MRF-50) as a release substrate. The above coating solution was applied so that the thickness of the coating was 100 μm. This was dried at 130 ° C. for 2 minutes to form one light diffusion layer on the film. Thus, the sheet | seat (base sheet A) in which the light-diffusion layer 2 was formed was manufactured (FIG. 3 a).

  Three base sheets A were prepared. The other two light diffusion layers were laminated on one of the light diffusion layers 2 (the release substrate was removed) to produce a sheet having a thickness of 300 μm (see FIG. 3d). The lamination conditions at this time were the conditions of superimposing at 1500 rpm at 100 ° C. using a thermal laminator (Nitto Seiki Co., Ltd .: NLE-550ST).

  A cylindrical through hole 5 having a diameter of 6 mm is punched in the sheet obtained as described above (FIG. 4a), the release substrate 1 on one side is peeled off (FIG. 4b), and then the through hole is opened. Another release substrate 1 that was not bonded was laminated thereon and laminated in the same manner as above to produce a sheet in which the light diffusion layer 2 was provided with the opening 4 (FIG. 4c).

  Next, the sealing material composition liquid used in order to form a sealing layer was prepared. That is, 40.2 mmol of aluminum isopropoxide was added to 0.2 mol of both-end silanol type silicone oil (Shin-Etsu Chemical Co., Ltd .: KF-9701) and stirred at room temperature for 24 hours. The resulting mixture was centrifuged to remove insoluble matters. Subsequently, the obtained liquid was concentrated under reduced pressure at 50 ° C. for 2 hours to obtain polyaluminosiloxane oil. 1 part by weight of an epoxy silane coupling agent (Shin-Etsu Chemical Co., Ltd .: KBM-403) was added to 10 parts by weight of this polyaluminosiloxane oil, and the mixture was stirred at 80 ° C. for 7 minutes under reduced pressure to obtain a modified silicone resin. This was added to the modified silicone resin so that the amount of yellow phosphor (sialon) was 12% by weight to obtain a sealing material composition liquid. The viscosity of this sealing material composition liquid was 800 mPa · s.

  Next, the release substrate 1 on the side where the through-holes of the manufactured sheet are opened is peeled off (FIG. 7), and the sealing material composition liquid obtained above is the same height as the surrounding light diffusion layer 2 ( The opening 4 was filled with a dispenser so as to be 300 μm). In the state as it is, it heated at 100 degreeC for 5 minute (s), and the sealing layer 3 of a semi-hardened state was formed (FIG. 8). The shape of the sealing layer 3 formed at this time was a cylindrical shape with a circular cut surface, a cross-sectional diameter of 6 mm, and a height of 300 μm. In this way, an optical semiconductor element sealing sheet of the present invention was manufactured (FIG. 8).

(Example 2)
An optical semiconductor device was manufactured using the optical semiconductor element sealing sheet manufactured in Example 1 as follows.

  First, a printed circuit board on which a 1 mm square blue light emitting diode (SemiLEDs: SL-U40AC) was mounted was prepared. An optical semiconductor element sealing sheet was placed on the substrate surface so that the sealing layer was aligned with the position facing the optical semiconductor element. Subsequently, it crimped | bonded for 60 second at 0.3 MPa and 150 degreeC using the vacuum laminator (Nichigo Morton: V-130). Thereafter, the light diffusion layer and the sealing layer were cured at 150 ° C. for 2 hours to complete the lamination. Next, the release substrate was peeled off to produce an optical semiconductor device of the present invention.

  The structure of such an optical semiconductor device has the structure schematically shown in FIGS.

  A current of 50 mA was passed through the manufactured optical semiconductor device, and the total luminous flux was measured with an instantaneous multi-photometry system (Otsuka Electronics Co., Ltd .: MCPD-3000). As a result, the luminance (Y value) was 1400.

(Comparative Example 1)
Two pieces of the above base sheet A were prepared. In the same manner as in Example 1, a sheet (FIG. 3c) in a state where a 200 μm light diffusion layer was formed was produced. The sealing material composition liquid used in Example 1 was applied onto the light diffusion layer 2 of this sheet so that the thickness of the sealing layer to be formed was 100 μm, and heated as it was at 100 ° C. for 5 minutes. Then, a semi-cured sealing layer was formed to produce an optical semiconductor element sealing sheet.

  Next, the same printed circuit board 12 mounted with the blue light emitting diode as that used in Example 2 was prepared. On this board | substrate, it bonded together so that the sealing layer of the sheet | seat for optical semiconductor element sealing might contact a diode. Next, an optical semiconductor device was manufactured by the same method as in Example 2 (FIG. 9). As a result of measuring the total luminous flux under the same measurement conditions as in Example 1, the luminance (Y value) was 1250.

(Comparative Example 2)
An optical semiconductor element sealing sheet was produced in the same manner as in Example 1 except that the barium sulfate particles were not blended in the coating solution (FIG. 10). In FIG. 10, a resin layer 21 (a layer obtained by removing light diffusion particles from the light diffusion layer) is provided instead of the light diffusion layer 2.

  Next, an optical semiconductor device was manufactured in the same manner as in Example 2, and the total luminous flux thereof was measured. The luminance (Y value) in this example was 1250.

  As described above, the optical semiconductor device (Example 2) of the present invention is more than the example in which the light diffusion layer is provided on the sealing layer (Comparative Example 1) and the example in which there is no light diffusion particle (Comparative Example 2). It was found that the light extraction efficiency of the optical semiconductor element was excellent.

(Example 3)
An optical semiconductor device encapsulated in the same manner as in Example 1 except that silicon dioxide particles (volume average particle size: 8 μm; Tokai Chemical Industry Co., Ltd .: ML-369W) were used instead of barium sulfate particles as light diffusion particles. A stop sheet was produced. Subsequently, the optical semiconductor device was manufactured by the method similar to Example 2 using the obtained sheet | seat for semiconductor element sealing, and the total luminous flux was measured. As a result, the luminance (Y value) was 1350, and the manufactured optical semiconductor device had excellent light extraction efficiency.

Example 4
An optical semiconductor element sealing sheet was produced in the same manner as in Example 1 except that the coating solution for forming the light diffusion layer was replaced with the coating solution prepared as described below. That is, 100 parts by weight of barium sulfate particles (volume average particle diameter: 5 μm; Takehara Chemical Industry: W-6) are added to 100 parts by weight of the modified silicone resin obtained in Example 1, and the coating solution is prepared. Obtained.

  Subsequently, the optical semiconductor device was manufactured by the method similar to Example 2 using the obtained sheet | seat for semiconductor element sealing, and the total luminous flux was measured. As a result, the luminance (Y value) was 1350, and the manufactured optical semiconductor device had excellent light extraction efficiency.

(Example 5)
A sheet for sealing an optical semiconductor element is produced in the same manner as in Example 1, except that the sealing material composition liquid for forming the sealing layer is replaced with the sealing material composition liquid prepared as follows. did. That is, to 300 parts by weight of ethyl acetate as a solvent, 50 parts by weight of methyl methacrylate as a monomer, 45 parts by weight of butyl methacrylate and 5 parts by weight of methacrylic acid, and 1 part by weight of azobisisobutyronitrile as a polymerization catalyst were added. Polymerization was performed at 80 ° C. in a nitrogen atmosphere to obtain a polymer solution. To 100 parts by weight of the polymer solution, 5 parts by weight of bisphenol A type epoxy resin (Japan Epoxy Resin Co., Ltd .: EP828), 1 part by weight of trimethoxyboroxine as a curing catalyst and 15 parts by weight of sialon are added to this polymer solution. Thus, a sealing material composition liquid based on an acrylic resin was obtained. The viscosity of this sealing material composition liquid was 800 mPa · s.

  Subsequently, the optical semiconductor device was manufactured by the method similar to Example 2 using the obtained sheet | seat for semiconductor element sealing, and the total luminous flux was measured. As a result, the luminance (Y value) was 1350, and the manufactured optical semiconductor device had excellent light extraction efficiency.

  As shown in Examples 3 to 5, the optical semiconductor element sealing sheet and the optical semiconductor device have a unique structure as in the present invention, so that the light diffusing particles, the light diffusing layer, and the sealing material It was found that, regardless of the type, a very good light extraction efficiency of the optical semiconductor element can be achieved.

  The optical semiconductor element sealing sheet of the present invention can further improve the light extraction efficiency of the optical semiconductor element. In addition, since the optical semiconductor device of the present invention further improves the light extraction efficiency of the optical semiconductor element, by using the optical semiconductor device of the present invention, various products (backlights of liquid crystal screens, traffic lights, outdoor devices) can be used. The quality of large displays, billboards, etc.) can be further improved.

FIG. 1 is a schematic view showing an example of the optical semiconductor element sealing sheet of the present invention, and is a top view. FIG. 2 is a schematic view showing an example of the optical semiconductor element sealing sheet of the present invention, and is a cross-sectional view taken along line B-B ′ of FIG. 1. FIG. 3 is a schematic view showing a manufacturing process of the optical semiconductor element sealing sheet of the present invention, and is a cross-sectional view. FIG. 4 is a schematic view showing a manufacturing process of the optical semiconductor element sealing sheet of the present invention, and is a cross-sectional view. FIG. 5 is a schematic view showing an example of the optical semiconductor device of the present invention, and is a top view. 6 is a schematic view showing an example of the optical semiconductor device of the present invention, and is a cross-sectional view taken along line A-A ′ of FIG. 5. FIG. 7 is a schematic view showing a manufacturing process of the optical semiconductor element sealing sheet of the present invention, and is a cross-sectional view. FIG. 8 is a schematic view showing a manufacturing process of the optical semiconductor element sealing sheet of the present invention, and is a cross-sectional view. FIG. 9 is a schematic view showing an example of an optical semiconductor device in which a light diffusion layer is provided on a sealing layer, and is a cross-sectional view. FIG. 10 is a schematic view showing an example of an optical semiconductor element sealing sheet having no light diffusing particles, and is a cross-sectional view.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Release base material 2 Light-diffusion layer 3 Sealing layer 4 Opening part 5 Through-hole 11 Optical semiconductor element 12 Wiring circuit board 21 Resin layer (The layer remove | excluding the light-diffusion particle from the light-diffusion layer)

Claims (2)

An optical semiconductor element sealing sheet comprising at least a release substrate, a sealing layer and a light diffusion layer,
The light diffusion layer is provided on the release substrate,
The light diffusion layer is provided with an opening, and the sealing layer is provided in the opening.
Optical semiconductor element sealing sheet.   An optical semiconductor device formed by sealing an optical semiconductor element using the optical semiconductor element sealing sheet according to claim 1.

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