JPH1117073A - Optical coupler and sealing resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a an optical coupled and sealing resin composition which can have a high optical conversion efficiency and a high sensitivity and can secure a high reliability to disturbance light. SOLUTION: An optical coupler includes a light emitting element 1 and a light receiving element 2 connected to parts of electrode leads 5 and 6 and buried in a light-permeable resin 3, and also includes a resin sealing material 4 as an envelope of the burying material 3. The resin sealing material 4 is made of synthetic resin and an inorganic filling material. The inorganic filling material contains inorganic filling material covered with titanium oxide. The sealing resin composition contains synthetic resin and inorganic filling material and also inorganic filling material coated with titanium oxide.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optically coupled semiconductor device and a resin composition for sealing the same, and more particularly to an optically coupled semiconductor device excellent in photoelectric conversion efficiency and light shielding ability for preventing malfunction. is there.

[0002]

2. Description of the Related Art In general, an optically coupled semiconductor device combines a light emitting element and a light receiving element, inputs an electric signal to the light emitting element, receives light energy radiated from the light receiving element, converts the light energy into an electric signal, and inputs / outputs the signal. Between them, the input signal is transmitted to the output side in a completely electrically separated state, and is generally provided by the name of an optocoupler or an opto-isolator, and is used for logic circuit coupling, analog relay, motor control, etc. Widely used.

FIG. 1 shows a circuit configuration of a typical optical coupling semiconductor device, FIG. 2 shows a longitudinal sectional view thereof, and FIG. 3 shows a cutaway perspective view. 1 to 3, reference numeral 1 denotes a light emitting element on the input side,
As element, GaAsP element, GaP element and the like are used. On the other hand, 2 is a light receiving element on the output side, for which a phototransistor, a photothyristor, a photodiode or the like is used. Reference numeral 3 denotes an embedding body for transferring light between the light emitting element and the light receiving element, and a transparent resin such as a silicone resin is often used as the embedding resin. Reference numerals 5 and 6 denote lead electrodes composed of a metal frame, which are made of a thin plate made of a Fe-Ni alloy such as a 42 alloy or a Cu alloy. Reference numeral 4 denotes a resin sealing body for protecting the internal element from the external environment.

Generally, a black resin or a white resin prepared for an optical coupling semiconductor element is used as a sealing resin.
Black resin has been used in the past, but in the case of black resin, most of the light emitted from the light-emitting element and incident on the embedded transparent resin-sealing black resin interface is carbon particles contained in the black resin. Is absorbed by Therefore, the photoelectric conversion efficiency (CTR), which is an important performance of the optical coupling semiconductor device, is reduced. This measure has been studied, and at present, a white sealing resin is widely used to reflect light at the interface between the transparent resin and the sealing resin (Japanese Patent Publication No. 57-6711).

[0005]

As described above, a white resin excellent in light reflectivity is often used for a resin sealing body such as a photocoupler. However, new performance has been required for white resin due to recent changes in package form. That is, the package is rapidly changing from a conventional thick package for through-hole mounting (FIG. 1) to a thin package for surface mounting (FIG. 4). For example, the thickness of the through-hole mounting DIP (dual inline package) of FIG. 1 is about 4 mm, while the thickness of the surface mount type SOP (small outline package) of FIG. 2 is about 2 mm. Furthermore, T
For SOP (Thinner Small Outline Package), its thickness is about 1 mm. When the thickness is reduced in this manner, the thickness of the light shielding wall from the package surface to the light receiving element becomes thin, and there is a problem that the conventional white sealing resin is likely to malfunction due to disturbance light.

The conventional white encapsulating resin is composed of 20 to 30% by weight of an epoxy resin using an organic acid anhydride or a novolak type phenol resin as a curing agent, 50 to 75% by weight of a fused silica powder, and 5 to 20% by weight of a titanium dioxide powder. , And others. In the white sealing resin having this configuration, the light reflecting ability and light shielding ability required for the resin are realized by adding titanium dioxide powder. Therefore, if the thickness is reduced and the influence of disturbance light is increased, it is easily envisioned that silica powder is not added and titanium dioxide powder alone is added or the ratio of titanium dioxide powder is further increased. .

However, increasing the mixing ratio of titanium dioxide in the white sealing resin has the following disadvantages. That is, the water absorption increases, and the moisture resistance reliability evaluated by the pressure cooker test (PCT), which is indispensable for semiconductor devices, decreases. In addition, the coefficient of thermal expansion increases, and the thermal reliability evaluated by the heat cycle test (TCT) decreases. Further, a reverse bias load high-temperature storage test (HTR
The heat resistance evaluated in B) decreases.

In short, the present invention is intended to solve the above-mentioned problems, and is an optical coupling semiconductor which has high light conversion efficiency, can achieve high sensitivity, and can secure the reliability of a device against disturbance light. An object is to provide an apparatus and a sealing resin composition.

[0009]

The inventor of the present invention has conducted intensive studies on a useful white composite resin as an encapsulating resin for an optically coupled semiconductor device, and as a result, has found that ordinary semiconductor devices such as a storage element (memory), By coating the surface of the high-purity inorganic filler powder mixed with the sealing resin such as ASIC (Application Specific Integrated Circuit) with a titanium dioxide layer, it has excellent high temperature stability in addition to low moisture absorption and low thermal expansion. The present inventors have found that the above problems can be solved by providing a white sealing resin, and forming an envelope of an optical coupling semiconductor device using the white sealing resin, and have completed the present invention.

In one embodiment of the encapsulating resin composition of the present invention, a high-purity fused silica powder is first coated with a curable silicone compound as a binder, and fine titanium dioxide powder is sheared by a high-speed mixer. After mixing while applying force, the titanium dioxide powder is adhered to the surface of the fused silica powder, and then the curable silicone compound is solidified at a high temperature, as shown in the schematic sectional view of FIG. To obtain a titanium dioxide-coated fused silica powder coated with a titanium dioxide layer 8. Next, this titanium dioxide-coated fused silica powder was put into a mixing tank, and further an epoxy resin powder, an organic acid anhydride as a curing agent,
After adding and mixing a catalyst as a curing accelerator and a lubricant as a release agent, the mixture is melt-kneaded with a twin-screw heating roll or the like, cooled, and pulverized to obtain a white sealing resin powder. This white sealing resin is
Since the filler is made of fused silica powder coated with titanium dioxide, it has low water absorption, low thermal expansion and photothermal stability compared to high light reflectance and high light shielding white sealing resin to which titanium dioxide powder is added. A white encapsulating resin having light reflecting ability and high light shielding ability can be obtained. This resin is compressed into tablets (large vertical tablets) so that they can be molded by a low-pressure transfer molding machine.

Next, in one embodiment according to the optical coupling semiconductor device of the present invention, a light emitting element and a light receiving element are connected to an element mounting portion of a lead frame, and a liquid or water which becomes a rubber or gel silicone resin upon curing. A light transmitting passage is formed between the light emitting element and the light receiving element with a candy-like uncured silicone resin, and gelled or cured before sealing molding so as not to be damaged in the molding machine. Next, the lead frame equipped with the optical coupling semiconductor element is placed on the heated lower mold of the low-pressure transfer molding machine, the upper mold is lowered, and the mold is closed,
After the white sealing resin tablet preheated by a preheater or the like is charged into the tablet input port of the molding machine, the plunger is lowered or raised to lower the heated and melted white sealing resin into a runner (grooved resin injection path), a gate ( Pouring) into the cavity. The resin cures in approximately 1-3 minutes. The optical coupling semiconductor device connected with the cured lead frame is removed from the mold, the lead frame is punched out (punched out) into an appropriate shape, and the external leads, which are connection terminals to the outside, are arranged in an appropriate shape and optically coupled. The semiconductor device is completed. The optical coupling semiconductor device is often additionally heated (aftercure) in order to provide better reliability. The conditions are 150 ° C. to 180 ° C. for 4 to 8 hours. The optical coupling semiconductor device manufactured in this manner has a water absorption, a low thermal expansion property using a fused silica powder coated with titanium dioxide,
Since the white encapsulation resin, which is photothermally stable, has high light reflectance and high light shielding properties, is used as the envelope, it has excellent moisture resistance, cold heat reliability, and heat resistance, which are indispensable for semiconductor devices. An optical coupling semiconductor device with high light conversion efficiency and high sensitivity can be manufactured.

Hereinafter, the present invention will be described in more detail.

First, an inorganic filler and titanium oxide powder constituting the titanium oxide-coated inorganic filler of the present invention,
Further, a coating method will be described.

The inorganic filler used in the present invention includes:
Although all types can be used, high-purity inorganic powders that do not dissociate ionic impurities that adversely affect the device when moisture and high temperature are applied are suitable due to the restrictions imposed on the sealing of the semiconductor device. Further, in order to prevent a decrease in reliability due to stress applied to the element surface, a low expansion inorganic powder is suitable. For this purpose, high-purity glass powder such as fused silica powder, fused silica spheres, crystalline silica powder, alumina oxide powder, silicon nitride powder, aluminum nitride powder, E glass, or glass spheres, glass fibers, and even flame retardant Antimony oxide powder such as antimony trioxide, antimony tetroxide, and antimony pentoxide required for application can also be used. Cleaning such as acid cleaning or coating such as hard coating may be performed to prevent elution of ionic impurities from these inorganic powders. Among these inorganic powders, fused silica powder is most preferred.

As the titanium oxide used in the present invention, all kinds can be used. However, it is preferable that the titanium oxide has an average particle size of 5 μm or less for the purpose of coating the above-mentioned inorganic filler. More preferably, it is 1 μm or less. As the titanium oxide, rutile-type titanium dioxide and anatase-type titanium dioxide can be used.

The method for coating the inorganic filler for the present invention may be any method, but it is necessary that the inorganic filler is firmly adhered to the inorganic filler to uniformly cover the inorganic filler. The coating method is exemplified below.

First, there is a method using a silicone resin as a coating binder. This can be a two-part liquid silicone resin. The first liquid of the liquid silicone resin is a silicone oil having a SiH group, and the second liquid is a silicone oil having a carbon double bond. These two liquids are mixed and fused silica powder (average particle size 12 μm)
Attached (coated) to the surface, and then a titanium dioxide powder (average particle size 1 μm)
After adhering m), it can be cured by heating to obtain a titanium dioxide-coated fused silica powder.

Further, there is a method in which a thermosetting resin such as an epoxy resin is used as a coating binder. The powder or liquid epoxy resin is added to the fused silica powder while stirring with a heated granulation and mixing apparatus, and a curing agent such as a phenol resin or an acid anhydride and a phosphorus-based catalyst are added. After the titanium dioxide powder is adhered to the surface of the fused silica powder having the cured adhesive epoxy layer, it is cured by heating to obtain a titanium dioxide-coated fused silica powder.

Further, there is a method using a thermoplastic resin such as engineering plastics as the coating binder. A low molecular weight norbornene resin dissolved in a solvent is added while stirring the fused silica powder with a granulating and mixing apparatus, and then titanium dioxide powder is added and adhered, followed by degassing under reduced pressure to obtain a titanium dioxide-coated fused silica powder. be able to. Alternatively, after adding a low molecular weight norbornene resin dissolved in a solvent, the solvent was distilled off by heating under reduced pressure, and then heated to a high temperature of 300 ° C. or more to give the norbornene resin an adhesive property. Titanium dioxide powder may be applied later and cooled to obtain a titanium dioxide-coated fused silica powder.

As still another example, ethanol is charged into a chemical reaction tank, an alcohol solution of titanium is added, diethanolamine is further added, and the fused silica powder is immersed in the solution to form a thin film on the surface of the fused silica powder. . Thereafter, there is also a method of drying and heating to a high temperature to obtain a titanium dioxide-coated fused silica powder.

Furthermore, a method using a silicone compound having a high hardness called a hard coat layer as a coating binder, or an inorganic film precursor can also be used. Furthermore, it is also possible to coat while suspending titanium dioxide and fused silica powder in a high-temperature furnace.

Since the surface properties of the titanium dioxide-coated fused silica powder produced by each of the above methods are different, it is preferable to use differently depending on the type of the binder resin of the white sealing resin. A combination in which the titanium dioxide-coated fused silica powder and the binder resin are firmly adhered after the white sealing resin is cured is preferable.

As the synthetic resin as a raw material of the encapsulating resin composition of the present invention, first, a plastic or engineering plastic having high light transmittance can be used in order to increase the light reflectance. As plastic or engineering plastic, for example, polystyrene,
Styrene-acrylic copolymer, ABS resin, acrylic resin, polyphenylene oxide, polycarbonate resin, norbornene resin, and the like can be used. Among them, a polycarbonate resin and a norbornene resin having excellent heat resistance are preferable.

When these plastics are used as a matrix, the plastic raw materials, the titanium dioxide-coated fused silica powder and the lubricant are uniformly mixed, and then charged into a twin-screw extruder, and melt-mixed and extruded by heating under shearing force. Can be prepared. The extruded sealing resin is
An optical coupling semiconductor device is manufactured by an injection (injection) molding machine equipped with a device-sealing mold by granulating, cooling, and pelletizing by a granulator (pelletizer) according to the procedure of the transfer molding machine.

The synthetic resin as a raw material of the encapsulating resin composition of the present invention includes melamine resin, xylene resin, unsaturated polyester resin, alkyd resin, diaryl phthalate resin, triaryl cyanurate resin, cellulose resin, Epoxy resins and the like can be mentioned. Among them, it is preferable to use an epoxy resin having good adhesiveness. Among the epoxy resins, it is preferable to use an organic acid anhydride or a novolak-type phenol resin that hardly discolors when heated, and a carbon-added black encapsulating resin prepared for encapsulating general semiconductor devices. It is desirable to use a composition excluding carbon from the base.

The light emitting device used in the present invention is GaAs.
An s element, a GaAsP element, a GaP element, or the like is used. On the other hand, as the light receiving element, a phototransistor, a photothyristor, a photodiode, or the like is used.
Although the arrangements are various, they can be broadly classified into a reflection arrangement (FIG. 5) and an opposed arrangement (FIG. 6).

That is, in the case of the reflection type arrangement, as shown in FIG. 5, both the elements 1 and 2 are mounted (mounted) on a portion called a bed arranged in a plane and connected to an external circuit. After connecting to the internal leads 5 and 6 using the connecting thin wires, the two elements 1 and 2 are transparently liquid silicone resin 3.
2 and is embedded in a lens shape.
In order to reflect the light L emitted from the resin at the interface between the resin sealing body 4 and the lens-shaped silicone resin 3 and efficiently send the light L to the light receiving element 2, the sealing resin composition of the present invention surrounds the silicone resin 3 Is molded (molded). In the case of this reflective arrangement, the reflectance of the white resin directly affects the photoelectric conversion efficiency.

On the other hand, in the case of the opposed type arrangement, as shown in FIG. 6, a bed is formed up and down, and the light receiving element 2 and the light emitting element 1 are mounted facing up or down and connected to an external circuit. After connecting with the internal leads 5 and 6 for connection using thin connecting wires (not shown), a transparent liquid silicone resin 3 is embedded in a shape connecting both the elements 1 and 2, and then the light L emitted from the light emitting element 1 Among them, in order to efficiently send the light escaping from the side surface of the silicone resin 3 to the light receiving element, the white resin sealing body 4 is formed by surrounding the silicone resin 3 with the sealing resin composition of the present invention (mold). I do. Also in the case of the opposed arrangement structure, the reflectance of the white resin affects the photoelectric conversion efficiency.

As described above, in the optical coupling semiconductor device of the present invention, the light emitting element and the light receiving element are connected to the electrode lead or a part of the electrode lead group, and the light emitting element and the light receiving element are made of a light transmitting resin. In the optical coupling semiconductor device which is embedded and has a resin sealing body constituting an envelope of each element including the embedding body or the embedding body, the resin sealing body is made of a synthetic resin and an inorganic filler. Wherein the inorganic filler includes an inorganic filler coated with titanium oxide, and in the optical coupling semiconductor device, the synthetic resin of the resin sealing body is an epoxy resin; An optical coupling semiconductor device in which the base material for the titanium-coated inorganic filler is a powder selected from silica, alumina, silicon nitride, and aluminum nitride, and is resin-encapsulated. Is a plastic or engineering plastic having a light transmitting property, and the base material for the inorganic filler and the titanium oxide-coated inorganic filler is a powder selected from silica, alumina, silicon nitride, and aluminum nitride. Device.

On the other hand, the encapsulating resin composition of the present invention having a light reflecting ability and a light shielding ability comprises a synthetic resin and an inorganic filler, and the inorganic filler comprises an inorganic filler coated with titanium oxide. In the sealing resin composition, the synthetic resin is an organic acid anhydride-curable or phenolic resin-curable epoxy resin, and the titanium oxide-coated silica powder is based on the entire composition. The encapsulating resin composition is contained in the range of 20% by weight to 85% by weight, and the synthetic resin is a polycarbonate resin or a norbornene resin, and the titanium oxide-coated silica powder is contained in an amount of 20% by weight to the entire composition. 85
It is a sealing resin composition contained in the range of% by weight.

[0031]

As described above, according to the present invention, by coating the surface of the inorganic filler powder with a titanium dioxide layer, a white encapsulating resin having excellent high-temperature stability in addition to low hygroscopicity and low thermal expansion can be obtained. When the envelope is made of the white sealing resin, excellent device reliability can be provided to the optical coupling semiconductor device.

The core idea of the present invention is that an inorganic powder such as silica, which is suitable as a filler for a semiconductor encapsulating resin in terms of mechanical properties and other properties but is inferior in light reflecting ability and light blocking ability, and a high light reflectance From the standpoint of maximizing the respective functions of titanium oxide powder with high light-shielding properties, by fixing titanium oxide powder on the surface of inorganic powder or forming titanium oxide layer on the surface, necessary mechanical properties etc. While maintaining, the disturbance light path that passes through silica powder or the like and reaches the light receiving element is blocked, so that the light conversion efficiency of the optical coupling semiconductor device can be improved and malfunction due to disturbance light can be eliminated, and Various reliability of the optical coupling semiconductor device can be improved.

[0033]

Embodiments of the present invention will be described below. In addition, a comparative example is also described for comparison with the prior art. First, the coating fillers (A) to (D) used as the titanium oxide-coated inorganic filler will be described.

Coating filler (A) 5 kg of high-purity fused silica powder for semiconductor encapsulating resin (weight average particle diameter 14 μm, crushed), 1 kg of titanium dioxide powder (anatase type: weight average particle diameter 1 μm), and 50 g of a liquid mixture of a self-adhesive heat-curable liquid silicone rubber (additional two-component type) is prepared.

A horizontal stirring blade and a vertical stirring blade on the side surface;
In addition, the above-mentioned fused silica powder is charged into a granulating and stirring device also provided with a heating and cooling mechanism and a reduced-pressure exhaust mechanism, and stirred at room temperature. After one minute, the above liquid silicone rubber is sprayed in by a spray method, and stirring is continued. Two minutes after the introduction of the liquid silicone rubber, the above-mentioned titanium dioxide powder is added from the introduction port in the form of a fine stream over a period of two minutes while the temperature is raised. One minute after the introduction of the titanium dioxide powder, reduce the stirring speed and turn on the granulation stirring device for 150 minutes while slightly operating the vacuum exhaust.
Heat up to ° C. After elapse of 3 minutes after the temperature was raised, cooling was started, cooled to room temperature and taken out to prepare a coated filler (A).

Coating filler (B) High purity fused silica powder (weight average particle diameter 10 μm, spherical)
5 kg, titanium dioxide powder (rutile type: weight average particle size
0.8 μm) 1 kg, liquid bisphenol A type epoxy resin (epoxy equivalent 180, viscosity 5000 csp / 52 ° C) 35
g, 14 g of methylated hexahydrophthalic anhydride (liquid) as a curing agent, and 1 g of diazabicycloundecene (liquid) as a catalyst are prepared.

The above fused silica powder is charged into the same granulating and stirring apparatus as in the case of the coating filler (A), and the mixture is stirred at room temperature. One minute later, the above diazabicycloundecene is sprayed in by a spray method, and stirring is continued for 30 seconds. Next, the above-mentioned methylated hexahydrophthalic anhydride is sprayed in the same manner, and the liquid bisphenol A-type epoxy resin is immediately injected with a syringe. Next, the titanium dioxide powder is added from the charging port in the form of a fine stream over 2 minutes. After one minute has passed since the introduction of the titanium dioxide powder, reduce the stirring speed,
The temperature of the granulation stirrer was raised to 1550 while slightly operating the vacuum evacuation.
Increase to ° C. 1 minute after the temperature rise, start cooling,
It was cooled to room temperature and taken out to prepare a coating filler (B).

Coating filler (C) 5 kg of high-purity fused silica powder (weight average particle diameter: 14 μm, crushed), 1 kg of titanium dioxide powder (rutile type: weight average particle diameter: 0.8 μm), and 30 g of norbornene resin
Prepare a norbornene resin solution dissolved in 100 g of xylene solvent.

5 kg of the above fused silica powder is charged into a granulating and stirring apparatus similar to the method for producing the coated filler (A), followed by stirring at room temperature. One minute later, the norbornene resin solution is sprayed in by a spray method, and stirring is continued for one minute. Next, the above-mentioned titanium dioxide powder is added from the inlet in the form of a fine stream over 2 minutes. One minute after the introduction of the titanium dioxide powder, reduce the stirring speed, and raise the temperature of the granulation stirring device to 100 ° C. while operating the vacuum evacuation device. After elapse of one minute from the temperature rise, cooling was started, cooled to room temperature and taken out to prepare a coating filler (C).

Coating Filler (D) Instead of the high-purity fused silica powder, 7.5 kg of silicon nitride powder (weight average particle diameter 12 μm, crushed) was used in accordance with the method for preparing the coating filler (A). ) Was prepared.

Example 1 First, 170 g of cresol novolak type epoxy resin powder (epoxy equivalent: 220, softening point: 84 ° C.) was used as raw materials.
77 g of novolak type phenol resin powder (hydroxyl equivalent: 104, softening point: 75 ° C.), 4 g of triphenylphosphine powder,
Coating filler (A) powder 740 g, carnauba wax powder 6
g and 3 g of an epoxysilane coupling agent liquid are weighed and prepared.

High-speed mixing and stirring device (Henschel mixer)
The coating filler (A) is added to the mixture, and after mixing for 1 minute, the epoxysilane coupling agent is added by spraying. After that, cresol novolak type epoxy resin, novolak type phenol resin, triphenylphosphine powder,
Carnauba wax powder is added sequentially to prepare a homogeneous mixture of filler and resin. Next, a biaxial roll (front roll 75 ° C,
Thereafter, the mixture is put into a roll (105 ° C.), and after kneading for 2 minutes, the sheet-like white resin is taken out from the roll, cooled, and pulverized to prepare a white epoxy resin powder. This powder is formed into tablets with a tableting machine and used for sealing the optically coupled semiconductor device with a low-pressure transfer molding device.

To evaluate the performance of the optically coupled semiconductor device, two types of TEGs (test elements) were prepared. A TEG-A (type shown in FIG. 6) in which a light emitting element and a light receiving element are opposed to each other and sealed in a thick (4 mm) package, and a thin type (2) in which the light emitting element and the light receiving element are arranged on the same plane. mm) is a TEG-B (type in FIG. 5) sealed in a package. TEG-A is used for measuring the photoelectric conversion efficiency.
GB was used for evaluating the influence of disturbance light. Three each of TEG-A and TEG-B arranged on the lead frame were sealed using a low-pressure transfer molding machine. The sealing was performed at 175 ° C. for 3 minutes. After encapsulation molding, the lead is cut off, the external lead shape is adjusted, and the white resin encapsulated optical coupling semiconductor device manufactured by after-curing at 170 ° C for 4 hours is evaluated for light conversion efficiency, influence of disturbance light, etc. Used for

Example 2 A white epoxy resin powder was prepared according to the method of Example 1 by using the coating filler (B) powder in place of the coating filler (A) powder, and tablets of the white epoxy resin powder were prepared. A white resin-sealed optically coupled semiconductor device was fabricated using the method.

Example 3 A white epoxy resin powder was prepared according to the method of Example 1 by using the coating filler (C) powder instead of the coating filler (A) powder, and tablets of the white epoxy resin powder were prepared. A white resin-sealed optically coupled semiconductor device was fabricated using the method.

Example 4 In place of 740 g of the coated filler (A) powder, 140 g of high-purity fused silica powder (14 μm in weight average particle size, crushed) and 600 g of the coated filler (A) powder were used. A white epoxy resin powder was prepared according to the method of Example 1, and a white resin sealed optically coupled semiconductor device was manufactured using the tablet of the white epoxy resin powder.

Example 5 In place of 740 g of the coated filler (A) powder, 240 g of high-purity fused silica powder (weight average particle diameter 14 μm, crushed) and 500 g of the coated filler (A) powder were used. A white epoxy resin powder was prepared according to the method of Example 1, and a white resin sealed optically coupled semiconductor device was manufactured using the tablet of the white epoxy resin powder.

Example 6 In place of 740 g of the coated filler (A) powder, 340 g of high-purity fused silica powder (14 μm in weight average particle size, crushed) and 400 g of the coated filler (A) powder were used. A white epoxy resin powder was prepared according to the method of Example 1, and a white resin sealed optically coupled semiconductor device was manufactured using the tablet of the white epoxy resin powder.

Example 7 In place of 740 g of the coated filler (A) powder, 440 g of a high-purity fused silica powder (weight average particle diameter 14 μm, crushed) and 300 g of the coated filler (A) powder were used. A white epoxy resin powder was prepared according to the method of Example 1, and a white resin sealed optically coupled semiconductor device was manufactured using the tablet of the white epoxy resin powder.

Example 8 Instead of 740 g of the coated filler (A) powder, 540 g of high-purity fused silica powder (14 μm in weight average particle size, crushed) and 200 g of the coated filler (A) powder were used. A white epoxy resin powder was prepared according to the method of Example 1, and a white resin sealed optically coupled semiconductor device was manufactured using the tablet of the white epoxy resin powder.

Example 9 In place of cresol novolak type epoxy resin, novolak type phenol resin and triphenylphosphine,
Method of Example 1 using 180 g of trifunctional epoxy resin (triglycidyl isocyanurate, solid) powder, 68 g of organic acid anhydride (hexahydrophthalic anhydride, solid) powder, and 3 g of diazabicycloundecene (liquid) And a white resin sealed optically coupled semiconductor device was manufactured using the white epoxy resin powder tablet.

Example 10 In place of 740 g of the coated filler (A) powder, 340 g of high-purity fused silica powder (weight average particle diameter 14 μm, crushed) and 400 g of the coated filler (D) powder were used. A white epoxy resin powder was prepared according to the method of Example 1, and a white resin sealed optically coupled semiconductor device was manufactured using the tablet of the white epoxy resin powder.

Example 11 5 kg of norbornene resin powder, 9.74 kg of high-purity fused silica powder (weight average particle diameter: 14 μm, crushed), 0.5 k of E-glass short fiber (milled fiber, average length: 0.2 mm) 0.5 k
g, 4.5 kg of the coating filler (C) powder, 80 g of carnauba wax powder, 120 g of polyethylene wax powder, and 60 g of vinylsilane coupling agent liquid.

High-speed mixing and stirring device (Henschel mixer)
Then, high-purity fused silica powder, E-glass short fiber, and coating filler (C) powder are charged and mixed for 1 minute, and then a vinylsilane coupling agent is added by spraying. Thereafter, norbornene resin powder, carnauba wax powder, and polyethylene wax powder are added and mixed. Next, the mixture is put into a twin-screw extruder (extruder) from a hopper, heated and kneaded, and then pelletized by a pelletizer. This white pellet was used for sealing an optical coupling semiconductor device with an injection device. Production of TEG (test element) is described in Example 1.
It went according to. However, norbornene resin-sealed TE
In the case of G, after-cure was not performed.

Example 12 Instead of 740 g of the coated filler (A) powder, 440 g of high-purity fused silica powder (weight average particle diameter 12 μm, spherical) and 300 g of the coated filler (A) powder were used. A white epoxy resin powder was prepared according to the method of Example 1, and a white resin sealed optically coupled semiconductor device was manufactured using the tablet of the white epoxy resin powder.

Comparative Example 1 In the composition of Example 1, high-purity fused silica powder (weight average particle size: 14 μm) was used instead of 740 g of the coating filler (A) powder.
m, crushed) Using 615 g of titanium dioxide powder (125 g of anatase type: weight average particle diameter 1 μm) and 125 g of titanium dioxide powder, a white epoxy resin powder was prepared according to the method of Example 1, and a tablet of the white epoxy resin powder was prepared. A white resin-sealed optically coupled semiconductor device was fabricated using the method.

Comparative Example 2 In the composition of Example 1, high-purity fused silica powder (weight average particle diameter 14 μm) was used in place of 740 g of the coating filler (A) powder.
m, pulverized) Using 490 g of titanium dioxide powder and 250 g of titanium dioxide powder (anatase type, weight average particle size: 1 μm), a white epoxy resin powder was prepared according to the method of Example 1, and a tablet of the white epoxy resin powder was prepared. A white resin-sealed optically coupled semiconductor device was fabricated using the method.

Comparative Example 3 In the composition of Example 1, high-purity fused silica powder (weight average particle diameter: 14 μm) was used instead of 740 g of the coating filler (A) powder.
A white epoxy resin powder was prepared according to the method of Example 1 using 240 g of titanium dioxide powder (anatase type: weight average particle diameter 1 μm) and 240 g of titanium dioxide powder. A white resin-sealed optically coupled semiconductor device was fabricated using the method.

Comparative Example 4 High-purity fused silica powder (weight average particle diameter: 14 μm) was used in place of 740 g of the coating filler (A) powder in the composition of Example 1.
m, crushed) 240 g, titanium dioxide powder (rutile type:
Using 500 g of a weight average particle diameter (0.8 μm), a white epoxy resin powder was prepared according to the method of Example 1, and
A white resin-sealed optically coupled semiconductor device was manufactured using the white epoxy resin powder tablet.

Comparative Example 5 In the composition of Example 1, high-purity fused silica powder (weight average particle diameter: 14 μm) was used instead of 740 g of the coating filler (A) powder.
m, crushed) Using 740 g, an epoxy resin powder was prepared according to the method of Example 1, and a white resin-sealed optically coupled semiconductor device was manufactured using a tablet of the epoxy resin powder.

The white epoxy resin powder and the epoxy resin powder were evaluated for water absorption under pressure, expansion coefficient and volume resistivity at high temperature, and the results are shown in Table 1. The evaluation method is as follows.

Pressurized water absorption: A disk having a diameter of 5 cm and a thickness of 3 mm was prepared, dried at 150 ° C. for 2 hours, weighed, and measured in a pressure cooker (127 ° C. saturated steam atmosphere). After humidification in water for 15 hours, the weight was weighed, and the water absorption (% by weight) was measured from the difference.

Expansion coefficient: TMA (thermomechanical property measuring device)
The sample (4 mm ×
The expansion amount (4 mm × 17 mm) was measured, and the thermal expansion coefficient (rate) was determined from the sample length and the expansion amount per unit temperature.

High temperature volume resistivity: diameter 10 cm, thickness 3 mm
A disk with a voltage of 500 V was impressed between circular electrodes placed above and below the disk in a dryer at 150 ° C, the leakage current after 1 minute was measured, and the value and the size of the electrode were measured. The volume resistivity at 150 ° C. was determined from the thickness of the disk.

A white resin-sealed optically coupled semiconductor device was manufactured and subjected to a PCT test and an HTRB test.
It was shown to. The evaluation method of the white resin-sealed optically coupled semiconductor device and the resin-sealed optically coupled semiconductor device is as follows.

PCT test: TEG-A was placed in a pressure cooker (127
(Saturated steam atmosphere at ℃) and inspected for defects such as disconnection and leak at regular intervals. Table 2 shows the number of defects occurring after 1000 hours.

TCT test: TEG-A was placed in a thermal cycle test tank (one cycle at -155 ° C. × 30 min and + 150 ° C. × 30 min), and defects such as disconnection and leak were inspected at regular intervals. Table 2 shows the number of failures occurring after 500 cycles.

High temperature reverse bias storage test: TEG-A
Put into a 125 ° C constant temperature bath, apply reverse bias voltage,
Defects such as disconnection and leak were inspected at regular intervals. Table 2 shows the number of failures after 500 hours.

Table 3 shows the results of the CTR test and the disturbance light test of the white resin-sealed optically coupled semiconductor device and the resin-encapsulated optically coupled semiconductor device. The evaluation method is as follows.

Photoelectric conversion efficiency evaluation test: C of TEG-A
TR (input / output conversion efficiency: Current Transfer Ratio) was measured. The result was calculated from the value of the resin-encapsulated optically-coupled semiconductor device manufactured from the epoxy resin powder containing no titanium oxide of Comparative Example 5 as 100.

Evaluation test of influence of disturbance light: TEG-B and T
Bring the fluorescent lamp up to 1 mm above the EG-A package,
The electromotive force of the light receiving element was measured.

[0072]

[Table 1]

[0073]

[Table 2]

[0074]

[Table 3]

[0075]

As described above, according to the present invention, by coating the surface of the inorganic filler powder with the titanium dioxide layer, it is possible to obtain a white sealing material having excellent high-temperature stability in addition to low moisture absorption and low thermal expansion. A sealing resin can be provided, and when the envelope is made of the white sealing resin, excellent device reliability can be imparted to the optical coupling semiconductor device. Taking advantage of this characteristic, the white sealed optically coupled semiconductor device of the present invention can improve the performance of electronic components such as logical circuit coupling, analog relays, and motor control. Further, the electronic component to which the present invention is applied can be reduced in size and thickness, and is suitable for application to portable devices and the like. That is, it is possible to cope with miniaturization of semiconductor-related products, and its industrial value is extremely high.

[Brief description of the drawings]

FIG. 1 is a circuit diagram of an optical coupling semiconductor device.

FIG. 2 is a longitudinal sectional view of the optical coupling semiconductor device.

FIG. 3 is a partially cutaway perspective view of the optical coupling semiconductor device.

FIG. 4 is a longitudinal sectional view of a thin optical coupling semiconductor device.

FIG. 5 is a longitudinal sectional view of an optical coupling semiconductor device of a reflection type arrangement.

FIG. 6 is a vertical cross-sectional view of the optical coupling semiconductor device in the opposed arrangement.

FIG. 7 is a schematic cross-sectional view of a titanium oxide-coated inorganic filler.

[Explanation of symbols]

 Reference Signs List 1 light emitting element 2 light receiving element 3 embedded body (light transmitting resin) 4 resin sealing body (sealing resin) 5 input electrode lead (light emitting side) 6 output electrode lead (light receiving side) 7 inorganic filler 8 titanium oxide layer

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08K 9/02 C08L 45/00 C08L 45/00 63/00 C 63/00 B 69/00 69/00 101/00 101/00 C09C 3/06 C09C 3/06 H01L 21/56 J H01L 21/56 31/12 A 31/12 23/30 R

Claims (6)

[Claims] 1. A light-emitting element and a light-receiving element are connected to an electrode lead or a part of an electrode lead group, and the light-emitting element and the light-receiving element are embedded in a light-transmitting resin. In an optical coupling semiconductor device provided with a resin sealing body constituting an envelope of each element including a body,
An optically coupled semiconductor device, wherein the resin sealing body is made of a synthetic resin and an inorganic filler, and the inorganic filler contains an inorganic filler coated with titanium oxide. 2. The synthetic resin of the resin sealing body is an epoxy resin, and the inorganic filler and the base material for the titanium oxide-coated inorganic filler are powders selected from silica, alumina, silicon nitride, and aluminum nitride. Item 2. The optical coupling semiconductor device according to Item 1. 3. The synthetic resin of the resin sealing body is a plastic or an engineering plastic having a light transmitting property, and the inorganic filler and the base material for the titanium oxide-coated inorganic filler are selected from silica, alumina, silicon nitride, and aluminum nitride. The optically coupled semiconductor device according to claim 1, wherein the optically coupled semiconductor device is a powder. 4. A sealing resin composition having a light reflecting ability and a light shielding ability, comprising a synthetic resin and an inorganic filler, wherein the inorganic filler comprises an inorganic filler coated with titanium oxide. . 5. The synthetic resin is an organic acid anhydride-curable or phenol resin-curable epoxy resin, and the titanium oxide-coated silica powder is contained in an amount of 20 to 85% by weight based on the whole composition. Item 6. A sealing resin composition having a light reflecting ability and a light shielding ability according to Item 4. 6. The light-reflecting ability and light beam according to claim 4, wherein the synthetic resin is a polycarbonate resin or a norbornene resin, and the titanium oxide-coated silica powder is contained in the range of 20% by weight to 85% by weight based on the whole composition. A sealing resin composition having a shielding ability.