Resin-molded article for optical semiconductor package, optical semiconductor packaging material, and optical semiconductor device

Abstract

The present application relates to a resin molding for optical semiconductor packaging, an optical semiconductor packaging material, and an optical semiconductor device. The present application provides a resin molding for optical semiconductor packaging which is less likely to generate cracks and voids during molding, and an optical semiconductor packaging material and an optical semiconductor device obtained using the resin molding for optical semiconductor packaging. A resin molding for optical semiconductor packaging for an optical semiconductor packaging material having a thinnest portion of 300 μm or less, the resin molding for optical semiconductor packaging having a compression rate of 90% or more, and the proportion of particles having a particle size of 125 μm or less in the resin molding for optical semiconductor packaging being 15% or less.

Description

TECHNICAL FIELD

[0001] The present application relates to a resin molding for optical semiconductor packaging, an optical semiconductor packaging material, and an optical semiconductor device. BACKGROUND

[0002] An optical semiconductor element is packaged by a ceramic package or a plastic package to make a device. Here, the ceramic package is not mainstream because the material constituting it is expensive and mass productivity is poor, and thus the plastic package is mainstream. Among them, from the viewpoint of workability, mass productivity, and reliability, a technique of pre-compressing an epoxy resin composition into a tablet shape and then performing transfer molding of the resulting molding is mainstream.

[0003] Incidentally, in the epoxy resin composition for optical semiconductor packaging used in the plastic package, the components of the epoxy resin, the curing agent, and the curing accelerator are difficult to disperse, and it is difficult to uniformly mix and disperse the whole, and thus there is a problem that the curing reaction becomes non-uniform and it is easy to generate a molding unevenness and a molding void. There is a problem that optical unevenness occurs due to these unevenness and void, and thus the reliability of the optical semiconductor device is impaired.

[0004] In order to solve these problems, in Patent Literature 1, a technique of ensuring the uniform dispersibility of the composition, reducing the molding unevenness and the molding void, and thus eliminating the optical unevenness by using a material obtained by very finely pulverizing an epoxy resin composition into a tablet is disclosed.

[0005] PRIOR ART DOCUMENTS

[0006] PATENT LITERATURE

[0007] [Patent Literature 1] Japanese Patent Application Laid-Open No. 3-3258 SUMMARY

[0008] PROBLEMS TO BE SOLVED BY THE INVENTION

[0009] In recent years, with the miniaturization of optical semiconductor devices, it is desired to thin the packaging material for packaging an optical semiconductor element, and it is more required to suppress the generation of a void at the time of molding than ever before. In addition, the conventional resin tablet for optical semiconductor packaging containing a large amount of fine powder has a problem that it is easy to generate a crack.

[0010] An object of the present application is to provide a resin molding for optical semiconductor packaging which is not easy to generate a crack and is not easy to generate a void at the time of molding, and an optical semiconductor packaging material and an optical semiconductor device obtained using the resin molding for optical semiconductor packaging.

[0011] MEANS FOR SOLVING THE PROBLEMS

[0012] The present application relates to a resin molding for optical semiconductor packaging, wherein the resin molding for optical semiconductor packaging is used for an optical semiconductor packaging material having a thickness of 300 μm or less at the thinnest portion, the resin molding for optical semiconductor packaging has a compression rate of 90% or more, and the proportion of particles having a particle size of 125 μm or less in the resin molding for optical semiconductor packaging is 15% or less.

[0013] In the resin molding for optical semiconductor packaging described above, the proportion of particles having a particle size of 2000 μm or more is preferably 10% or less.

[0014] The resin molding for optical semiconductor packaging described above preferably contains a curable resin composition containing a thermosetting resin, a curing agent, and a curing accelerator.

[0015] The tablet hardness of the resin molding for optical semiconductor packaging described above is preferably 75 N or more.

[0016] In addition, the present application also relates to an optical semiconductor packaging material obtained by molding the molding described above, and having a thickness of 300 μm or less at the thinnest portion.

[0017] Further, the present application also relates to an optical semiconductor device having an optical semiconductor element and the optical semiconductor packaging material described above that encapsulates the optical semiconductor element.

[0018] Effects of the Invention

[0019] The resin molding for optical semiconductor packaging of the present application is less likely to generate voids even when molded into a thin type, and an optical semiconductor packaging material having excellent optical properties can be obtained. In addition, the resin molding for optical semiconductor packaging of the present application is less likely to generate cracks. DETAILED DESCRIPTION

[0020] Hereinafter, the present application will be specifically described.

[0021] The resin molding for optical semiconductor packaging (pellets, tablets, etc.) of the present application is used for an optical semiconductor packaging material having a thickness of 300 μm or less at the thinnest portion of the encapsulation portion of a semiconductor device, the resin molding for optical semiconductor packaging has a compression rate of 90% or more, and the proportion of particles having a particle size of 125 μm or less in the resin molding for optical semiconductor packaging is 15% or less. In such a thin type of packaging material, voids generated at the time of molding of the semiconductor packaging material can possibly have a large influence on optical properties. The molding of the present application is less likely to generate voids at the time of molding, and thus is suitable for the molding of a thin type of optical semiconductor packaging material as described above.

[0022] In the present specification, the optical semiconductor packaging material is a member that forms, in a manner to cover, an optical semiconductor element constituting an optical semiconductor device, and packages the element.

[0023] The thickness of the thinnest portion of the optical semiconductor packaging material of the resin molded product for optical semiconductor packaging according to the present application is 300 μm or less, preferably 250 μm or less, and more preferably 200 μm or less.

[0024] The compression rate of the resin molded product for optical semiconductor packaging according to the present application is 90% or more. By having a compression rate of 90% or more, generation of voids at the time of molding can be suppressed. From the aspect of further suppressing generation of voids, the compression rate is preferably 91% or more, and more preferably 92% or more. The upper limit of the compression rate is not particularly limited, and is preferably 96% or less.

[0025] The compression rate can be obtained as a value obtained by multiplying the ratio of the apparent specific gravity of the molded product to the specific gravity (true specific gravity) when the voids in the molded product are set to 0 (apparent specific gravity / true specific gravity) by 100. As the true specific gravity, the specific gravity of a cured product obtained by curing the molded product using a transfer molding machine under pressure (conditions of 150°C x 4 minutes) can be used.

[0026] In the resin molded product for optical semiconductor packaging according to the present application, the proportion of particles having a particle diameter of 125 μm or less is 15% or less. Since the proportion of particles having a particle diameter of 125 μm or less is 15% or less, generation of voids at the time of molding can be suppressed, and breakage of the molded product becomes less likely to occur. From the aspect of further suppressing generation of voids and making breakage of the molded product even less likely to occur, the proportion of particles having a particle diameter of 125 μm or less is preferably 12% or less, and more preferably 10% or less. The lower limit is not particularly limited, and can be 0.1%.

[0027] In the resin molded product for optical semiconductor packaging according to the present application, the proportion of particles having a particle diameter of 2000 μm or more is preferably 10% or less, and more preferably 4% or less. The lower limit is not particularly limited, and can be 0.1%. When the proportion of particles having a particle diameter of 2000 μm or more is within the above range, generation of voids at the time of molding can be further suppressed. In addition, optical unevenness of the packaging material, clogging of the mold, and the like can be suppressed, and small pieces having a small weight variation can be obtained.

[0028] The average particle diameter of the particles constituting the resin molded product for optical semiconductor packaging according to the present application is preferably 125 μm to 2000 μm, and more preferably 500 μm to 1000 μm.

[0029] The proportion of particles having a particle diameter of 125 μm or less, the proportion of particles having a particle diameter of 2000 μm or more, and the average particle diameter can be determined from the particle size distribution based on the number determined using a laser diffraction type particle size distribution measuring device.

[0030] In the resin molded article for optical semiconductor packaging of the present application, the tablet hardness is preferably 75 N or more, and more preferably 125 N or more. The upper limit of the tablet hardness is not particularly limited, and is preferably 330 N or less. When the tablet hardness is within the above range, the generation of voids at the time of molding can be further suppressed. In addition, the optical unevenness of the packaging material and the clogging of the mold can also be suppressed. In addition, a molded article having a small weight variation can be obtained.

[0031] Here, the tablet hardness described above can be measured by using a small block having a diameter of 13 mm and a weight of 2.4 g, and using a tablet hardness tester (manufactured by Okada Seiko Co., Ltd.).

[0032] The volume of the resin molded article for optical semiconductor packaging of the present application is not particularly limited, and is preferably 1 cm 3 to 100 cm 3 , and more preferably 10 cm 3 to 100 cm 3 .

[0033] The resin molded article for optical semiconductor packaging of the present application preferably contains a curable resin composition containing a thermosetting resin, a curing agent, and a curing accelerator. Note that a filler such as silica powder can be incorporated to the extent that the transmission of light is not impaired.

[0034] As the thermosetting resin, epoxy resins, polysiloxane resins, hybrid resins of epoxy resins / polysiloxane resins, and the like can be exemplified. Among them, epoxy resins are preferred.

[0035] As the epoxy resin, an epoxy resin having little coloration is preferred, and bisphenol A type epoxy resins, bisphenol F type epoxy resins, phenol novolak type epoxy resins, alicyclic epoxy resins, heterocycle-containing epoxy resins such as isocyanuric acid triglycidyl ester, hydantoin epoxy resins, hydrogenated bisphenol A type epoxy resins, aliphatic type epoxy resins, glycidyl ether type epoxy resins, and the like can be exemplified. They can be used alone or in combination of two or more.

[0036] There is no particular limitation as the curing agent, and an anhydride that causes little coloring of the cured body of the resin composition at or after curing is preferred. For example, phthalic anhydride, maleic anhydride, trimellitic anhydride, pyromellitic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, tetrahydrophthalic anhydride, methyl nadic anhydride, nadic anhydride, glutaric anhydride, and the like can be exemplified. In addition, as other curing agents, m-phenylenediamine, dimethyl diphenyl methane, diaminodiphenyl sulfone, m-xylene diamine, tetraethylenepentamine, diethylamine, propylamine, and the like as amine-based curing agents, phenol-based curing agents, and the like can be exemplified. These can be used alone or in combination of two or more.

[0037] The amount of the curing agent to be blended is not particularly limited, and for example, 20 to 200 parts by mass, more preferably 20 to 80 parts by mass, and further preferably 40 to 60 parts by mass, relative to 100 parts by mass of the thermosetting resin, is preferred. When the amount is less than 20 parts by mass, the speed of curing becomes slow, and when the amount exceeds 200 parts by mass, there is an excess relative to the curing reaction, and thus it can cause a decrease in properties.

[0038] As the curing accelerator, tertiary amines such as triethanolamine; imidazoles such as 2-methylimidazole; organophosphorus compounds such as tetraphenylborate and triphenylphosphine; diazabicycloalkene compounds such as 1,8-diazabicyclo[5.4.0]undec-7-ene and 1,5-diazabicyclo[4.3.0]non-5-ene; and the like can be exemplified. These can be used alone or in combination of two or more. As the curing accelerator, tertiary amines such as triethanolamine; imidazoles such as 2-methylimidazole; organophosphorus compounds such as tetraphenylborate and triphenylphosphine; diazabicycloalkene compounds such as 1,8-diazabicyclo[5.4.0]undec-7-ene and 1,5-diazabicyclo[4.3.0]non-5-ene; and the like can be exemplified. These can be used alone or in combination of two or more.

[0039] The amount of the curing accelerator to be blended is not particularly limited, and for example, 0.1 to 5 parts by mass, preferably 0.5 to 3 parts by mass, and more preferably 1 to 2 parts by mass, relative to 100 parts by mass of the thermosetting resin, can be appropriately selected from the range. When the amount of the curing accelerator is too small, the speed of curing becomes slow, and the productivity decreases, and on the other hand, when the amount of the curing accelerator is too large, the speed of the curing reaction becomes fast, and it is difficult to control the state of the reaction, and thus it can cause variation in the reaction.

[0040] In the resin molded article for a light semiconductor package of the present application, in addition to the above-described components, an additive such as an anticoloring agent, a lubricant, a modifier, a deterioration inhibitor, a mold releasing agent, a phosphor that changes the wavelength of light, an inorganic / organic filler that diffuses light, and the like can be used as needed.

[0041] As the anticoloring agent, a phenolic compound, an amine compound, an organic sulfur compound, a phosphine compound, and the like can be exemplified.

[0042] As the lubricant, waxes such as stearic acid, magnesium stearate, calcium stearate, talc, and the like can be listed. Note that in the case of incorporating the above lubricant, the amount of incorporation is appropriately set in accordance with the tablet molding conditions, and for example, it is preferably set to 0.1 to 0.4 mass% of the entire resin composition.

[0043] As the phosphor that changes the wavelength of light, the inorganic / organic filler that diffuses light, silica powder such as quartz glass powder, talc, fused silica powder, and crystalline silica powder, alumina, silicon nitride, aluminum nitride, silicon carbide, and the like can be listed. Note that in the case of incorporating the phosphor, the inorganic / organic filler, the amount of incorporation can be appropriately set in accordance with the tablet molding conditions. Specifically, in the case of the phosphor, the amount of incorporation of the phosphor can be appropriately set from the range of 1 to 60 mass% of the entire resin composition. On the other hand, in the case of the filler (organic / inorganic) that scatters light, the filler that scatters light can be appropriately set from the range of 0.5 to 25 mass% of the entire resin composition.

[0044] The resin molded article for optical semiconductor packaging of the present application is used for resin packaging of optical semiconductor elements such as light-receiving elements, and thus a transparent resin molded article is preferable from the viewpoint of optics. Here, "transparent" means that the transmittance at 400 nm of the cured product of the curable resin composition constituting the above small pieces is 90% or more. Note that the transmittance in the case of containing the above additive such as the phosphor that changes the wavelength of light, the inorganic / organic filler that diffuses light, the colorant, and the like means the transmittance of the resin portion after removing the additive.

[0045] The resin molded article for optical semiconductor packaging of the present application can be appropriately manufactured, for example, by a manufacturing method comprising the following steps:

[0046] a step of kneading a thermosetting resin, a curing agent, and a curing accelerator to obtain a curable resin composition;

[0047] a step of heat-treating the curable resin composition;

[0048] a step of granulating the curable resin composition to obtain a granular curable resin composition; and

[0049] a step of tablet molding the granular curable resin composition into a small piece shape.

[0050] The method of kneading is not particularly limited, and for example, a method using an extruder or the like can be listed. The kneading temperature is also not particularly limited, and can be appropriately changed in accordance with the characteristics of the thermosetting resin, and can be set to be high in a manner such that the reaction proceeds at the time of kneading. Specifically, 80 to 150°C is preferable, and 110 to 130°C is more preferable.

[0051] The shape of the curable resin composition obtained by performing the kneading is not particularly limited, and examples include film, sheet, particle, block, and the like.

[0052] The thickness of the curable resin composition obtained by performing the kneading is not particularly limited, and is preferably 1 mm to 30 mm, and more preferably 2 mm to 20 mm. When less than 1 mm, the thickness is thin, and is easily affected by moisture absorption, and when more than 30 mm, the time until cooling is required, and there is a tendency for the reaction to vary due to internal heat storage.

[0053] The curable resin composition obtained by performing the kneading is subjected to heat treatment, and a B-stage (semi-cured) resin composition for optical semiconductor packaging is obtained. The heat treatment temperature is not particularly limited, and is preferably 25°C to 100°C, and more preferably 60°C to 80°C. When less than 25°C, the curing reaction is slow, and there is a tendency for the productivity to decrease, and when more than 100°C, the curing reaction is fast, and there is a tendency for it to be difficult to end in a prescribed reaction state. The heat treatment time is not particularly limited, and can be appropriately changed depending on the characteristics of the thermosetting resin.

[0054] The resin composition after the heat treatment is granulated, and a particulate curable resin composition is obtained. As the granulation method, a method using a dry-type crushing granulator, a method using a dry-type compression granulator, and the like can be exemplified, of which a method using a dry-type crushing granulator is preferred. The dry-type crushing granulation can be an impact-rotation type, a shear-swing type, a shear-rotation type, and the like, of which a shear-swing type is preferred. Before the granulation, pulverization using a ball mill, a turbo mill, and the like can also be performed. In addition, the particles obtained by the pulverization or the granulation can also be sieved to adjust the particle size. By these methods, the proportion of particles having a particle diameter of 125 μm or less, the proportion of particles having a particle diameter of 2000 μm or more, and the average particle diameter can be adjusted to the above ranges.

[0055] The particulate curable resin composition obtained is formed into a small block by, for example, tablet molding, and a resin molding for optical semiconductor packaging of the present application is obtained. Since the particle size is adjusted by the above granulation, a high-quality small block having few defects, cracks, and a small weight deviation can be obtained. The tablet molding is performed in such a manner that the compression ratio of the molding is within the above range.

[0056] The resin molding for optical semiconductor packaging of the present application can package an optical semiconductor element by a molding method such as transfer molding. An optical semiconductor packaging material having a thickness of the thinnest portion of 300 μm or less obtained by molding the resin molding for optical semiconductor packaging of the present application is also one embodiment of the present application. The optical semiconductor packaging material of the present application is obtained from the molding of the present application, and thus, although it is an optical semiconductor having a thin portion with a thickness of the thinnest portion of 300 μm or less, it has few voids, and few optical unevenness and the like.

[0057] As the above-described optical semiconductor element, a light emitting diode (LED), a semiconductor laser (VCSEL or the like) element, a light receiving element, or the like can be exemplified.

[0058] An optical semiconductor device having the optical semiconductor element and the optical semiconductor packaging material of the present application that packages the optical semiconductor element is also one embodiment of the present application. The optical semiconductor device of the present application has the optical semiconductor packaging material of the present application, and therefore, in a case where the optical semiconductor device is operated to obtain a light receiving signal, has an advantage that signal variation due to optical unevenness does not occur, and a signal without noise can be obtained.

[0059] [Examples]

[0060] Next, the present application is described in more detail by exemplifying examples, but the present application is not limited to only these examples.

[0061] The materials used are shown below.

[0062] Epoxy resin 1: bisphenol-type epoxy resin A (epoxy equivalent 650)

[0063] Epoxy resin 2: isocyanuric acid triglycidyl ester (epoxy equivalent 100)

[0064] Curing agent 1: tetrahydrophthalic anhydride

[0065] Curing agent 2: mixture of 4-methylhexahydrophthalic anhydride and hexahydrophthalic anhydride Curing accelerator 1: N,N-dimethylbenzyl amine

[0066] Curing accelerator 2: methyltributyl phosphonium salt

[0067] Additive: alcohol modifier

[0068] Examples 1 to 4 and Comparative Examples 1 to 3

[0069] Each raw material was heated and melted and mixed in an extruder set to 130°C at a compounding amount shown in Table 1, and then the resin discharged from the discharge port of the extruder was molded into a thickness of 2 mm to 10 mm, and heat-treated at 60°C for 60 minutes, to obtain an epoxy resin composition. The obtained epoxy resin composition was granulated using a dry compression granulator, and then pulverized using a turbo mill, and then the proportions of fine powder having a particle diameter of 125 μm or less and large particles having a particle diameter of 2000 μm or more were adjusted using a 120 mesh sieve and a 10 mesh sieve, as shown in Table 1. Then, the obtained powder was tabletted into a diameter of 13 mm and a weight of 2.4 g using a rotary tablet press, thereby producing a resin slug for optical semiconductor packaging of a compression ratio shown in Table 1.

[0070] ​Using the obtained small pieces, the tabletability, tablet hardness, and void were evaluated by the following methods. The results are shown in Table 1.

[0071] <Tabletability>

[0072] The small pieces were visually observed for cracking, and evaluated according to the following criteria.

[0073] O: cracked

[0074] Δ: partially cracked

[0075] X: not cracked

[0076] <Tablet hardness of the tablet>

[0077] A 13φ x 2.4g small piece can be used, and the hardness at the time when the pressure is applied in the diameter direction at the time of cracking is measured using a tablet hardness meter (manufactured by Okada Seiko Co., Ltd.). Note that the evaluation was performed under the condition that the humidity was 50% or less, so that the humidity did not affect the cohesive force of the evaluation object. In addition, in the table, "-" indicates that the evaluation was not possible.

[0078] <Void>

[0079] A lens molding mold having a thickness of 300 μm at the thinnest portion and a lens height of 1 mm was used, and the obtained small pieces of the resin for optical semiconductor packaging were transfer molded, whereby an optical semiconductor packaging material was produced. The obtained packaging material was observed using a microscope at a magnification of 1000 times, 20 frames in which 600 lenses were formed were molded, the number of voids per number of lenses (600 x 20 frames) was calculated, and the evaluation was performed according to the following criteria.

[0080] O: less than 0.5 ppm

[0081] Δ: 0.5 ppm to 200 ppm

[0082] X: more than 200 ppm

[0083] -: evaluation was not possible because the small piece could not be produced.

[0084] Examples 5 to 8 and Comparative Examples 4 to 6

[0085] A small piece of the resin for optical semiconductor packaging was produced in the same manner as in Examples 1 to 4 and Comparative Examples 1 to 3, except that each raw material was used in the blending amount shown in Table 2. Using the obtained small piece, the tabletability, tablet hardness, and void were evaluated by the above-described methods. The results are shown in Table 2.

[0086] Table 1

[0087]

[0088] Table 2

[0089]

Claims

1. A resin molded article for optical semiconductor packaging, wherein, The resin molded material for optical semiconductor packaging is used for optical semiconductor packaging materials with a minimum thickness of 300 μm. The compression ratio of the resin molded article for optical semiconductor packaging is over 90%, and The proportion of particles with a diameter of 125 μm or less in the resin molded material for optical semiconductor packaging is 15% or less based on the number of particles.

2. The resin molded article for optoelectronic semiconductor packaging as described in claim 1, wherein, The proportion of particles with a diameter of 2000 μm or larger in the resin molded material for optical semiconductor packaging is less than 10%.

3. The resin molded article for optical semiconductor packaging as described in claim 1 or 2, wherein, The resin molded article for optical semiconductor packaging comprises a curable resin composition, which contains a thermosetting resin, a curing agent, and a curing accelerator.

4. The resin molded article for optical semiconductor packaging as described in claim 1 or 2, wherein, The tablet hardness of the resin molded material for opto-semiconductor packaging is 75N or higher.

5. A photonic semiconductor packaging material, wherein, The optical semiconductor packaging material is obtained by molding the optical semiconductor packaging resin molded article according to any one of claims 1 to 4, and the thickness of the thinnest part of the optical semiconductor packaging material is 300 μm or less.

6. An optical semiconductor device, wherein, The optical semiconductor device has an optical semiconductor element and an optical semiconductor packaging material as described in claim 5 for packaging the optical semiconductor element.

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