JP2009141066A - Manufacturing method of optical semiconductor device - Google Patents

Abstract

A method of manufacturing an optical semiconductor device in which color is simply adjusted using a chromaticity adjusting sheet in a device that emits white light using a blue LED element, and a color used in the manufacturing method To provide a degree adjustment sheet.
An optical semiconductor element chromaticity adjusting sheet comprising at least one resin sheet A containing a phosphor is laminated on a substrate on which an optical semiconductor element coated with a sealing resin layer B is mounted. A manufacturing method of an optical semiconductor device characterized by bonding, and an optical semiconductor element chromaticity adjusting sheet used in the manufacturing method.
[Selection figure] None

Description

  The present invention relates to a method for manufacturing an optical semiconductor device. More specifically, for example, a method for manufacturing an optical semiconductor device including a step of adhering a chromaticity adjusting sheet on a light emitting element such as a light emitting diode or a semiconductor laser coated with a sealing resin, and chromaticity used in the manufacturing method It is related with the sheet for adjustment.

  A light emitting device using a light emitting diode (LED) is generally manufactured by mounting an LED element on a substrate, and covering and sealing the element with a transparent resin layer in which a phosphor is dispersed in advance. can do. Therefore, the color of the light emitted from the device is determined by the type and concentration of the phosphor dispersed in the resin layer, the coating amount of the resin layer, etc. Once the LED element is sealed, the color of the light is changed. I can't do it.

  In addition, a device including an LED element and a sealing resin layer that contains a phosphor and is molded so as to cover the element has a problem that the color tone varies due to variations in the phosphor content in the sealing resin layer. was there.

On the other hand, in Patent Document 1, a non-wavelength conversion layer that does not substantially contain a phosphor is polished among resin layers that contain a phosphor, or a layer having a low phosphor content or substantially A method of adjusting the chromaticity by changing the thickness of the phosphor-containing resin layer by further applying a layer not included in the encapsulating resin layer is disclosed.
JP 2004-186488 A

  As a method of obtaining white light, for example, there is a method of combining a blue LED element and a yellow phosphor excited by a blue wavelength, but white light is subtle such as day white or warm white depending on the color temperature. Since there is a difference in color, the chromaticity can be adjusted by changing the thickness of the phosphor-containing layer according to the method of Patent Document 1, but the operation is complicated, so a delicate color It tends to be difficult to adjust. In addition, even in the case of an apparatus in which an LED element is once sealed with a phosphor-containing resin layer, there is a desire to finely adjust the color after sealing.

  An object of the present invention is to provide a method for manufacturing an optical semiconductor device in which color adjustment is simply performed using a chromaticity adjustment sheet in a device that emits white light using a blue LED element, and the manufacturing method. Another object of the present invention is to provide a chromaticity adjustment sheet used for the above. The device includes a device in which a blue LED element is already sealed with a phosphor-containing resin layer and the light color is determined. Also included is a method of manufacturing a device in which the color is adjusted to a desired color.

  As a result of repeated studies to solve the above-mentioned problems, the present inventors have obtained a white light that is emitted by using an optical semiconductor element chromaticity adjusting sheet comprising at least one resin sheet A containing a phosphor. The inventors have found that it is possible to produce an optical semiconductor device in which light is easily adjusted to a desired color, and have completed the present invention.

That is, the present invention
[1] An optical semiconductor element chromaticity adjusting sheet comprising at least one resin sheet A containing a phosphor is laminated and bonded onto a substrate on which an optical semiconductor element covered with a sealing resin layer B is mounted. The invention relates to a method for producing an optical semiconductor device, and [2] an optical semiconductor element chromaticity adjusting sheet used in the production method according to [1].

  According to the manufacturing method of the present invention, the color can be easily adjusted, and an optical semiconductor device that emits white light having a desired color can be obtained. In addition, the color of the luminescent color of the device having the light color once determined can be easily changed.

  The method for manufacturing an optical semiconductor device of the present invention is greatly characterized in that an optical semiconductor element chromaticity adjustment sheet is used for adjusting the color of white light emitted from the device.

  Conventionally, as a technique for adjusting the color of the luminescent color emitted from the device, a method of adjusting the phosphor content of the phosphor-containing resin layer that is a sealing resin layer, or a fluorescence of the phosphor-containing resin layer is used. The method of changing the thickness of the layer which does not contain a body substantially is mentioned. However, since the phosphor in the resin layer tends to settle, a uniform distribution cannot be obtained, and it is difficult to adjust to a constant color, and also when changing the thickness of the phosphor-containing resin layer, The work is complicated and the color cannot be easily adjusted.

  In the present invention, a chromaticity adjusting sheet including at least one resin sheet A containing a phosphor is laminated on the LED element covered with the sealing resin layer B and adhered to thereby obtain a constant color. Adjust to. In the chromaticity adjusting sheet, the type and concentration of the phosphor contained therein and the thickness of the resin sheet A can be arbitrarily set for the resin sheet A as a constituent component so as to obtain white light having a desired chromaticity. it can. Further, when the chromaticity adjusting sheet contains a plurality of resin sheets A, each resin sheet A is independently set with the type and concentration of the phosphor and the thickness of the resin sheet A. Even white light with a high chromaticity can be easily adjusted. The sealing resin layer B preferably contains a yellow phosphor in order to emit white light using a blue LED element.

  Moreover, the manufacturing method of the optical semiconductor device of this invention includes the process of adhering this sheet for chromaticity adjustment to the board | substrate with which the blue LED element sealed with the resin layer containing a yellow fluorescent substance was mounted. From the above, as the usage of the sheet in the production method of the present invention, after mounting a blue LED element on a substrate, the element is covered with a sealing resin containing a yellow phosphor, and the chromaticity adjusting sheet is adhered. In addition to (Aspect 1), the chromaticity adjusting sheet is adhered to an already produced optical semiconductor device, that is, an apparatus including a blue LED element already sealed with a resin layer containing a yellow phosphor ( Aspect 2) is exemplified. Note that an aspect in which the chromaticity adjustment sheet is further adhered to the light emitting device newly manufactured by adhering the chromaticity adjustment sheet, that is, an aspect in which the aspects of the aspects 1 and 2 are combined is also included in the present invention. It is included in the usage of the sheet.

  Next, the chromaticity adjusting sheet in the present invention, that is, the chromaticity adjusting sheet including at least one resin sheet A containing a phosphor will be described in detail below.

  Examples of the resin constituting the resin sheet A include the same resins as those conventionally used for the optical semiconductor element sealing sheet, and the adhesiveness with the sealing resin layer B or the substrate covering the LED element. If it has, there will be no limitation in particular.

  The resin sheet A can be obtained by thermosetting a resin such as polyethersulfone, polyimide, aromatic polyamide, polycarbodiimide, epoxy resin, triacetyl cellulose. Among these, a sheet made of an epoxy resin is preferable from the viewpoints of transparency and moldability. In addition, what is marketed may be used for each resin, and what was manufactured separately may be used.

  Examples of the epoxy resin include bisphenol types such as bisphenol A type and bisphenol F type, novolac type, nitrogen-containing ring type, alicyclic type, aromatic type, and modified types thereof. These may be used alone or in combination of two or more. Can be used in combination. Among these, bisphenol A type and alicyclic type are preferable from the viewpoint of film properties.

  The epoxy equivalent of the epoxy resin is preferably 500 to 7000, and more preferably 4000 to 5000. In addition, when using 2 or more types of epoxy resins, it is desirable that the epoxy equivalent of each resin is within the above range, but some of those outside the above range may be included, and the epoxy of the entire epoxy resin may be included. As an equivalent, the weighted average epoxy equivalent should just be contained in the said range.

  When the epoxy resin is cured, a curing agent or a curing accelerator may be used.

  Curing agents include acid anhydrides such as phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, 4-methylhexahydrophthalic anhydride, amines such as diethylenetriamine, triethylenetetraamine, diethylamine, and polyamides. And phenolic curing agents, and these can be used alone or in combination of two or more.

  The content of the curing agent can be appropriately determined according to the type of the curing agent to be used and the epoxy equivalent of the epoxy resin. From the viewpoint of obtaining sufficient strength for the molded sheet, for example, an acid anhydride type In the case of a curing agent, 0.8 to 1.2 equivalents are preferable and 0.9 to 1.1 equivalents are more preferable with respect to 1 equivalent of epoxy group of the epoxy resin.

  Examples of the curing accelerator include imidazole and phosphorus compounds, and these can be used alone or in combination of two or more.

  The content of the curing accelerator can be appropriately determined according to the acceleration effect and the like, but from the viewpoint of curing in a short time during molding, 0.1 to 5 parts by weight is preferable with respect to 100 parts by weight of the epoxy resin. -3 parts by weight is more preferred.

  The resin sheet A contains a phosphor. When the optical semiconductor device of the present invention emits white light, it is preferable to provide a sealing resin layer B containing a blue LED element and a yellow phosphor. A nitride compound such as a red phosphor or a green phosphor is preferably used.

The red phosphor is not particularly limited. For example, a known red phosphor such as a cascading red phosphor (CaAlSiN ₃ / Eu = 1/1, provided by National Institute for Materials Science) can be used.

  The green phosphor is not particularly limited. For example, a known green phosphor such as β-SiAlON (provided by National Institute for Materials Science) can be used.

  The content of the phosphor in the resin sheet A is preferably 1 to 30 parts by weight and more preferably 10 to 15 parts by weight with respect to 100 parts by weight of the resin constituting the resin sheet A.

  In addition, the resin sheet A may contain additives such as an antioxidant, a modifier, a surfactant, a dye, a pigment, and a color change inhibitor as raw materials from the viewpoint of durability against heat and light.

  For example, the resin sheet A is prepared by dissolving the raw materials such as the resin and the additive in an organic solvent such as toluene, cyclohexanone, methyl ethyl ketone, and the like, preferably in a concentration of 40 to 55% by weight. Prepare a resin solution by mixing, for example, form a film on a separator made of a biaxially stretched polyester film to an appropriate thickness by a method such as casting, spin coating, roll coating, etc., and further promote the curing reaction Instead, it is obtained by drying at a temperature at which the solvent can be removed. The temperature at which the resin solution is dried from the formed film varies depending on the type of resin and solvent and cannot be determined unconditionally, but is preferably 80 to 150 ° C, more preferably 100 to 140 ° C.

  The thickness of the resin sheet A1 layer after heat drying is preferably 10 to 500 μm, more preferably 100 to 300 μm, from the viewpoint of light transmittance. When adjusting the color, the absolute amount of the phosphor may be adjusted by changing the thickness of the resin sheet A.

  When the sheet for adjusting chromaticity is composed of one resin sheet A, the sheet obtained as described above may be used as it is. When a plurality of resin sheets A are contained, each resin sheet A is prepared and then laminated and, for example, a sheet formed by hot pressing at 140 to 150 ° C. is used. Alternatively, after one layer of the resin sheet A is laminated and adhered to the substrate, another resin sheet A may be laminated and adhered on the substrate, and the layers may be sequentially laminated and adhered.

  When the chromaticity adjusting sheet contains a plurality of resin sheets A, the thickness of the chromaticity adjusting sheet is preferably 10 to 500 μm, more preferably 100 to 300 μm, from the viewpoint of light transmittance.

  Thus, an optical semiconductor element chromaticity adjusting sheet capable of easily adjusting the color is obtained.

  In the manufacturing method of the present invention, a light emitting device is newly manufactured by adhering the chromaticity adjusting sheet. Specifically, a blue LED element is mounted on a substrate and a sealing resin containing a yellow phosphor is used. An optical semiconductor device can be manufactured by coating with the layer B, laminating the chromaticity adjusting sheets obtained above, and laminating them using a laminator or the like.

  The blue LED element used in the present invention is not particularly limited as long as it is an LED element having an emission peak near 460 nm. For example, those commercially available from Cree, Semireds, etc. are exemplified.

  Although the substrate on which the LED element is mounted is not particularly limited, for example, a rigid substrate in which copper wiring is laminated on a glass-epoxy substrate, a flexible substrate in which copper wiring is laminated on a polyimide film, and the like, such as a flat plate and an uneven plate An appropriate form can be used.

  As a method of mounting the LED element on the substrate, a face-up mounting method suitable for mounting an LED element having an electrode disposed on the light emitting surface, an LED element having an electrode disposed on the surface opposite to the light emitting surface is used. A flip lip mounting method suitable for mounting can be mentioned.

  The resin constituting the sealing resin layer B is not particularly limited as long as it is conventionally used as an optical semiconductor element sealing resin. Further, the yellow phosphor contained in the sealing resin layer B is not particularly limited, and for example, a known yellow phosphor such as YAG (Osram, manufactured by Kasei Optonix) can be used.

  When the chromaticity adjusting sheet in the present invention is melted by thermocompression bonding using a laminator or the like and bonded to the substrate, it is preferably heated at 100 to 200 ° C., more preferably 140 to 160 ° C., preferably 0.1 to 1.0 MPa. More preferably, the pressure is preferably 0.2 to 0.3 MPa.

[Softening point of resin sheet A]
The measurement resin is molded on a hot plate to a height of 2 mm, and when the hot plate is heated from room temperature, the temperature when the height of the measurement resin becomes 1 mm is defined as the softening point.

[Glass transition point of resin sheet A]
The measurement resin is molded into a strip having a thickness of 100 μm, a width of 0.5 cm, and a length of 5 cm, and the peak temperature of the tan θ curve when measured with DMS (DMS-200, manufactured by SIL) is defined as the glass transition point.

Chromaticity adjustment sheet production example 1
50 parts by weight of bisphenol A type epoxy resin (Epicoat EP1256, manufactured by Japan Epoxy Resin Co., Ltd.) with an epoxy equivalent of 7500, 30 parts by weight of alicyclic epoxy resin (3150CE, manufactured by Daicel Chemical Industries) with an epoxy equivalent of 150, 4-methylhexa Hydrophthalic anhydride (curing agent, MH-700, manufactured by Shin Nippon Chemical Co., Ltd.) 20 parts by weight, and 1.2 parts by weight of 2-methylimidazole (curing accelerator, manufactured by Shikoku Kasei Co., Ltd.) are added to methyl ethyl ketone at a concentration of 50% by weight. After mixing with stirring at 40 ° C for 1 hour, add 10 parts by weight of casoon red phosphor (CaAlSiN ₃ / Eu = 1/1, manufactured by National Institute for Materials Science) for coating. An epoxy resin solution was prepared.

  The obtained resin solution for coating is applied to a separator made of biaxially stretched polyester film (Mitsubishi Chemical Polyester Film Co., Ltd., thickness 38 μm) to a thickness of 100 μm, and dried at 100 ° C. for 1 minute. Thus, a semi-cured chromaticity adjusting sheet a was obtained. Table 1 shows the physical properties of the obtained sheet.

Chromaticity adjustment sheet production example 2
Instead of applying the coating resin solution to form a sheet to a thickness of 100 μm, instead of applying the coating resin solution to a thickness of 200 μm, the same procedure as in Chromaticity Adjustment Sheet Production Example 1 was performed. A chromaticity adjusting sheet b was obtained. Table 1 shows the physical properties of the obtained sheet.

Examples 1-2
Next, an optical semiconductor device is manufactured using the obtained chromaticity adjustment sheet. That is, the chromaticity adjustment sheet shown in Table 1 is laminated on a white LED substrate (a light emitting device having a flat structure in which a sealing resin layer containing a yellow phosphor is disposed on a blue LED element, manufactured by Cree), and 160 The optical semiconductor devices of Examples 1 and 2 were obtained by pressure bonding under the conditions of ° C and 0.3 MPa.

  The characteristics of the obtained LED device were examined according to the method of Test Example 1 below. The results are shown in Table 1.

[Test Example 1] (Chromaticity adjustment)
A current of 100 mA was passed through the LED device of each example, and the color temperature of the light immediately after the current was passed was measured by an instantaneous multi-photometry system (MCPD-3000, manufactured by Otsuka Electronics Co., Ltd.). On the other hand, the color temperature was also measured in the same manner as described above for an LED device (hereinafter referred to as reference device 1) in which the chromaticity adjusting sheet was not adhered to the white LED substrate used in Example 1. A color temperature corresponding to daylight white was 5000K, a color temperature corresponding to warm white was 3500K, and a color temperature of 3000 to 6500K was judged to have good chromaticity adjustment.

  From the above results, in the optical semiconductor devices of Examples 1 and 2 in which the chromaticity adjusting sheet is provided to the optical semiconductor device of Reference Example 1, the emission wavelength is converted by the red and green phosphors in the sheet. It has been found that an optical semiconductor device with an adjusted color tone can be manufactured by arbitrarily reducing the color temperature.

  Since the optical semiconductor device obtained by the manufacturing method of the present invention can be easily adjusted in color, it can be suitably used for, for example, in-vehicle lighting or street lamps.

FIG. 1 is a diagram illustrating the relationship between the thickness of the optical semiconductor element chromaticity adjustment sheet in Examples 1 and 2 and the color temperature of the emission color of the optical semiconductor element.

Claims (4)

  An optical semiconductor element chromaticity adjusting sheet comprising at least one resin sheet A containing a phosphor is laminated and adhered on a substrate on which an optical semiconductor element coated with a sealing resin layer B is mounted. A method for manufacturing an optical semiconductor device.   The manufacturing method according to claim 1, wherein the phosphor is a nitride compound.   The manufacturing method of Claim 1 or 2 whose resin which comprises the resin sheet A is an epoxy resin.   The sheet | seat for optical semiconductor element chromaticity adjustment used for the manufacturing method in any one of Claims 1-3.

Images