JP4058627B2 - Manufacturing method of resin lens for semiconductor optical element - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a resin lens for a semiconductor optical element, in particular, a liquid cured resin material for sealing a semiconductor optical element, and the cured product obtained by curing the sealing resin material. It is related with the manufacturing method of the resin lens for semiconductor optical elements used integrally on the sealing material which is.
[0002]
[Prior art]
There are various types of light emitting diodes (LEDs) such as a shell type and a chip type. Generally, a light emitting diode of a shell type transmits a light emitting body and a conductive member such as a cathode lead, an anode lead, a light emitting semiconductor chip, and a lead thin wire. The structure is sealed with a conductive resin. In the case of a chip-type light emitting diode, a pair of lead frames are extended from the inner bottom of a box-shaped light emitter housing member having an open upper surface to the outside of the light emitter housing member, and light is emitted into the light emitter housing member. It has a structure that houses semiconductor chips, lead wires, etc., connects them, and the inside of the housing member is sealed with a translucent resin. These light-emitting diodes are sealed according to their intended use. There is a case where a condensing lens for restricting the traveling direction of light emitted on the material is provided.
[0003]
Among these light-emitting diodes, when a lens is provided on a chip-type light-emitting diode, a light-emitting semiconductor chip or the like is housed in a light-emitting body housing member, and then this housing member is filled with a liquid sealing resin material. A method is adopted in which a lens is placed on a resin material for curing and the sealing resin material is cured and the sealing material and the lens are integrated. In this case, there are bubbles between the sealing material and the lens. In some cases, the bubbles are left behind. If bubbles are left behind, the remaining bubbles cause diffuse reflection or scattering of light, resulting in a decrease in luminance, resulting in a defective product.
[0004]
The prior art document information related to the present invention includes the following.
[0005]
[Patent Document 1]
JP-A-3-119769 [Patent Document 2]
JP-A-8-99368 [0006]
[Problems to be solved by the invention]
The present invention has been made in view of the above circumstances, and is mounted on a liquid sealing resin material for sealing a semiconductor optical element, such as a lens used in a chip-type light emitting diode. As a resin lens for a semiconductor optical element that is used on a sealing material that is a cured product by curing the resin material, the lens is placed on a liquid sealing resin material and the sealing resin material is cured. In this case, an object of the present invention is to provide a method capable of producing a resin lens for a semiconductor optical element with high productivity that can prevent bubbles from being left between the sealing material and the lens as much as possible.
[0007]
[Means for Solving the Problems]
As a result of intensive studies in order to solve the above problems, the present inventor, as long as the joint surface with the lens sealing material is a convex surface, air bubbles can escape along the curved surface, and the remaining of the air bubbles It was found that it was possible to avoid it. For this purpose, a convex lens in which both surfaces of the lens are convex surfaces can be used. When a resin lens having such a shape is molded by compression molding, in order to mold a relatively small resin lens for a semiconductor optical element. It is necessary to use an expensive metal mold that has been finely processed, and the problem is that burrs are likely to occur in the molded product. Deburring is a hindrance to the bonding with the sealing material and must be removed. However, with small resin lenses for semiconductor optical elements, deburring is an extremely complicated task that is not practical and causes burrs. Immediately become defective products, and manufacturing resin lenses for semiconductor optical elements by such compression molding has a poor yield.
[0008]
Accordingly, as a result of further studies, the present inventors have determined that a resin lens for a semiconductor optical element is provided with a cavity having a concave cross-section having a concave surface for forming a convex surface forming a condensing surface of the lens in a mold. A recess is provided, and the cavity recess is filled with a liquid lens resin material so that the lens resin material forms droplets that form a convex surface by the surface tension above the cavity recess. If it is manufactured by heating and curing the droplets, a resin lens having convex surfaces on both sides can be obtained. The surface corresponding to the concave surface of the mold is a condensing surface, and the convex surface on the opposite side of the condensing surface If it is used as a joint surface with the sealing resin material (sealing material), it has a function as a condensing lens, and the bubbles between the lens and the sealing resin material can be escaped to avoid residual bubbles. With possible convex surface This lens is not compressed at the time of molding, so there is no generation of burrs and the yield is very good. A resin lens for the above semiconductor optical element, particularly a relatively small resin lens used for a light emitting diode, is used. The present inventors have found that it can be produced with high productivity and have made the present invention.
[0009]
That is, the present invention is mounted on a liquid sealing resin material for sealing a semiconductor optical element, and is used by being integrated with a sealing material that is a cured product by curing the sealing resin material. A method for producing a resin lens for a semiconductor optical element, comprising: forming a cavity concave portion having a concave cross-section having a concave surface for forming a convex surface as a condensing surface of the lens in a mold; The lens resin material is filled in such a manner that the lens resin material becomes a droplet having a convex surface due to its surface tension above the cavity recess, and then the lens resin material droplet is heated to be cured. The manufacturing method of the resin lens for semiconductor optical elements characterized by these is provided.
[0010]
In such a resin lens for a semiconductor optical element, it is necessary that one surface thereof is a convex surface having a desired curvature. However, according to the manufacturing method of the present invention, the concave surface of the molding die has a desired curvature. By using the concave surface, it is possible to manufacture a lens in which a desired convex surface corresponding to the curvature of the concave surface is formed as a condensing surface.
[0011]
On the other hand, the surface that becomes the bonding surface with the sealing material is bonded to the lens and the sealing material after curing, so that it is not necessary to strictly adjust the curvature, and it should be a convex surface that can escape the bubbles. However, according to the manufacturing method of the present invention, when the lens resin material is integrated with the sealing resin material by forming a convex surface by the surface tension of the lens resin material and curing it, the lens and the sealing resin material It is possible to form a convex surface having a sufficient curvature to escape air bubbles remaining therebetween.
[0012]
In the manufacturing method of the present invention, in particular, if the cavity recess is formed in a shape including a disc-shaped recess and a cross-sectional arc-shaped recess formed in the lower center portion thereof, vibration or the like It is preferable because droplets of the lens resin material formed by surface tension against external force can be stably formed and maintained, and the droplets can be prevented from collapsing before curing.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
The present invention will be described in further detail below.
The method for producing a resin lens for a semiconductor optical element according to the present invention is a cured product obtained by placing on a liquid sealing resin material for sealing a semiconductor optical element and curing the sealing resin material. A method of manufacturing a resin lens for a semiconductor optical element used in an integrated manner with a sealing material, comprising: a cavity concave portion having a cross-sectional arc-shaped concave portion having a concave surface for forming a convex surface as a condensing surface of a lens in a mold. The lens recess material is filled with a liquid lens resin material so that the lens resin material becomes a droplet having a convex surface due to its surface tension above the cavity recess, and then the droplet of the lens resin material is provided. It is manufactured by heating and curing.
[0014]
In the present invention, the resin lens for a semiconductor optical element is provided with a cavity concave portion having a concave arc-shaped concave portion having a concave surface for forming a convex surface as a condensing surface of the lens in the mold, and the liquid lens is provided in the cavity concave portion. The resin material for a lens is filled so that the resin material for a lens becomes a droplet having a convex surface due to its surface tension above the cavity recess, and then the droplet of the resin material for a lens is heated to be cured. To do.
[0015]
Specifically as a shaping | molding die, the shaping | molding die 2 as shown by FIG. 1 (A)-(C) is mentioned, for example. In FIG. 1, reference numeral 2 denotes a mold, and a cavity recess 21 is formed on the upper surface 22 thereof. In this case, the cavity recess 21 has a shape including a disc-shaped recess 211 and a cross-sectional arc-shaped recess 212 formed at the lower center of the disc-shaped recess 211. The wall surface 212a of 212 is a concave surface for forming a convex surface that is a condensing surface of the lens, and the cavity concave portion 21 is filled with a liquid lens resin material.
[0016]
In the present invention, as will be described later, since the lens resin material is not compressed at the time of molding, any of metal, resin, and rubber can be applied as the molding die. Considering the thermal conductivity at the time, it is preferable to use a metal mold (mold).
[0017]
In the manufacturing method of the present invention, it is particularly preferable to use a mold in which the cavity recess is formed in a shape including a disk-shaped recess and a cross-sectional arc-shaped recess formed at the center lower portion thereof. More specifically, for example, a cavity recess 21 such as the molding die 2 shown in FIGS. 1A to 1C includes a disk-shaped recess 211 and a central lower portion of the disk-shaped recess 211. If it has the shape which consists of the cross-sectional arc-shaped recessed part 212 formed in this, the peripheral surface 211a which forms the disk-shaped recessed part 211 of the cavity recessed part 21, and the upper surface 22 of the shaping | molding die 2 are orthogonally crossed For example, as shown in FIG. 2 (A), the cavity recess 21 is formed only of the arc-shaped recess 212 in cross section, and the wall surface 212a and the upper surface 22 of the mold intersect at an obtuse angle. It is possible to stably form and maintain droplets of lens resin material formed by surface tension against external forces such as vibration than the mold, and prevent the droplets from collapsing before curing. Can also form a convex surface with a large curvature Preferable since it is possible to.
[0018]
In the present invention, it is also possible to use a mold as shown in FIG. Further, as shown in FIG. 2 (B), the cavity recess 21 has a disk-shaped recess 211, and a cross section having the same diameter as the disk-shaped recess 211 formed in the lower part of the disk-shaped recess 211. A mold having a shape including the arcuate recess 212 can also be suitably used.
[0019]
For example, as shown in FIG. 3, filling of the lens resin material and curing of the filled lens resin material is performed in the cavity recess 21 (FIG. 3A) formed in the mold 2. The resin material 3 is filled while adjusting the filling amount with the quantitative supply device 4 so that the lens resin material 3 becomes a droplet 31 having a convex surface 311 by the surface tension above the cavity concave portion 21 (FIG. 3B ), (C)), and the lens resin material droplet 31 is heated using the far-infrared heater 51, the IH heater 52, or both to cure the lens resin material droplet 31 (FIG. 3D). )) Is preferred.
[0020]
After the lens resin material droplet 31 is cured, it is cooled by air cooling with a blower 61 and water cooling or both via a heat sink 62 (FIG. 3E), and removed from the mold 2 by a take-out machine 7. The lens 1 can be obtained by molding (FIG. 3F). As shown in FIGS. 4A to 4D, the obtained lens 1 has a concave surface for forming a convex surface that serves as a condensing surface of the lens of the cavity concave portion 21, that is, a concave portion 212 having an arcuate cross section. It has a convex surface 11 corresponding to the wall surface 212a and a convex surface 13 corresponding to the convex surface 311 formed by the surface tension of the droplet 31 of the lens resin material. The convex surface 11 is the light condensing surface of the lens, and the convex surface 13 is the lens. And a bonding surface between the sealing material and the sealing material.
[0021]
In the above figure, an example in which one cavity recess is formed in the mold is illustrated, but the present invention is not limited to this. A plurality of cavity recesses are provided on the upper surface of one mold, and each cavity recess is provided. It is also possible to manufacture a lens by filling the lens resin material at once using a plurality of quantitative supply devices in order.
[0022]
In the present invention, a liquid resin material is used for the lens. As such a material, a conventionally known liquid resin material used for the production of a resin lens can be used, and a silicone resin composition is particularly preferably used. By curing such a liquid silicone resin composition, a lens made of silicone resin can be obtained. As the silicone resin composition, a liquid addition reaction curable silicone resin composition is particularly preferable. The liquid addition reaction curable silicone resin composition is suitable because it is solvent-free and can be uniformly cured on the surface and inside without foaming.
[0023]
The addition reaction curable silicone resin composition is not particularly limited as long as it forms a transparent silicone resin by heat curing. For example, organopolysiloxane is used as a base polymer, and organohydrogenpolysiloxane and platinum series are used. The thing containing heavy metal type catalysts, such as a catalyst, is mentioned.
[0024]
Examples of the organopolysiloxane include the following average unit formula R _a SiO _{(4-a) / 2}
Wherein R is an unsubstituted or substituted monovalent hydrocarbon group, preferably having 1 to 10 carbon atoms, particularly 1 to 8. a is a positive number of 0.8 to 2, particularly 1 to 1.8. Number.)
The thing shown by is mentioned. Here, R is an alkyl group such as a methyl group, an ethyl group, a propyl group or a butyl group, an alkenyl group such as a vinyl group, an allyl group or a butenyl group, an aryl group such as a phenyl group or a tolyl group, or an aralkyl such as a benzyl group. A halogen-substituted hydrocarbon group such as a chloromethyl group, a chloropropyl group, or a 3,3,3-trifluoropropyl group in which some or all of the hydrogen atoms bonded to these carbon atoms are substituted with a halogen atom, Or a cyano group-substituted hydrocarbon group such as a 2-cyanoethyl group substituted with a cyano group, and R may be the same or different, but those containing a phenyl group as R, particularly all R Of these, those in which 5 to 80 mol% is a phenyl group are preferred from the viewpoint of heat resistance and transparency of the optical lens.
[0025]
Further, those containing an alkenyl group such as a vinyl group as R, particularly those in which 1 to 20 mol% of all R are alkenyl groups are preferred, and those having two or more alkenyl groups in one molecule are preferably used. It is done. Examples of such an organopolysiloxane include terminal alkenyl group-containing diorganopolysiloxanes such as dimethylpolysiloxane having a terminal alkenyl group such as a vinyl group and a dimethylsiloxane / methylphenylsiloxane copolymer.
[0026]
On the other hand, the organohydrogenpolysiloxane is preferably trifunctional or higher (that is, one having three or more hydrogen atoms (Si-H groups) bonded to a silicon atom in one molecule), for example, methylhydrogenpolysiloxane. , Methylphenyl hydrogen polysiloxane, and the like, and liquids at room temperature are particularly preferable. Examples of the catalyst include platinum, platinum compounds, organometallic compounds such as dibutyltin diacetate and dibutyltin dilaurate, and metal fatty acid salts such as tin octenoate. The types and amounts of these organohydrogenpolysiloxanes and catalysts may be appropriately determined in consideration of the degree of crosslinking and the curing rate. In addition to the above components, fillers, heat-resistant materials, plasticizers and the like may be added to the extent that the strength and transparency of the resulting silicone resin are not impaired. Examples of the silicone resin composition include KE1935 (A / B) manufactured by Shin-Etsu Chemical Co., Ltd., XE14-062, XE14-907 manufactured by GE Toshiba Silicone Co., Ltd., SH6103, DX-35 manufactured by Toray Dow Corning Silicone Co., Ltd. Commercial products such as -547 can be used.
[0027]
In the present invention, the lens obtained by the above-described method is placed on a liquid sealing resin material for sealing a semiconductor optical element, and the sealing resin material is cured to obtain a cured product. For example, it is preferably used as a lens for a light emitting diode, particularly as a lens for a chip type light emitting diode.
[0028]
As shown in FIG. 5, the chip-type light emitting diode extends a pair of leads 101 and 102 from the inner bottom of the box-shaped light emitter housing member 105 having an open top surface to the outside of the light emitter housing member 105. The light emitting semiconductor chip 103 and the lead thin wires 104 and 104, which are light emitters, are accommodated inside the light emitter housing member 105, and these are connected, and the interior of the light emitter housing member 105 is sealed with a sealing material (translucent resin) 106. The lens 1 has a sealed structure, and is used by being bonded onto the sealing material 106.
[0029]
In this lens 1, after the light emitting semiconductor chip 103 and the like are accommodated in the light emitter housing member 105 and connected, a liquid sealing resin material 106 is filled in the light emitter housing member 105, and the lens 1 is placed on the sealing resin material 106. The convex surface 13 is placed facing the sealing resin material 106 side, and the sealing resin material 106 is cured by heating or the like, and is integrally joined. As shown in FIG. 6A, the sealing resin material Bubbles a entrained in the sealing resin material 106 when filling 106, an air layer b between the lens 1 and the sealing resin material 106 formed when the lens 1 is placed on the sealing resin material 106, etc. Is not completely removed from the inside of the light emitter housing member 105, after the sealing resin material 106 is cured, the remaining bubbles cause irregular reflection and scattering of light, resulting in a decrease in luminance. Good product And will. However, in this case, as shown in FIG. 6B, the air bubbles b in the sealing resin material 106 and the air layer b accumulated between the sealing resin material 106 and the lens 1 rise by buoyancy, Since it moves to the outer peripheral side of the lens 1 along the convex surface 13 of the lens 1 as indicated by an arrow in the drawing and is discharged to the outside from the gap 107 between the lens 1 and the light emitter housing member 105, the sealing resin After the material 106 is cured, no bubbles are left between the encapsulant and the lens.
[0030]
The manufacturing method of the present invention is particularly suitable for manufacturing a small resin lens having a diameter of about 1 to 30 mm and a thickness of about 0.5 to 30 mm. In the above example, the case where the chip type light emitting diode is used as the semiconductor optical element is illustrated. However, the present invention is not limited to this. For example, the optical element is used as a lens of a light receiving element for image formation in which a light receiving element chip is incorporated. It is also possible.
[0031]
【Example】
EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated concretely, this invention is not limited to the following Example.
[0032]
[Example 1]
As a lens resin material, a liquid silicone resin composition (XE14-907 (manufactured by GE Toshiba Silicone)) having an organopolysiloxane having a phenyl group bonded to a silicon atom as a base polymer was optically processed. A mold in which 100 cavity recesses having a shape as shown in FIG. 1 are formed is filled using a quantitative supply device so that the liquid silicone composition becomes droplets having a convex surface by surface tension, and these are heated and cured. After cooling, the mold was released from the mold, and 100 silicone resin lenses (diameter 6 mm, thickness 3 mm) as shown in FIG. 4 were produced. In any of these lenses, no burr was generated, and a convex surface due to surface tension was formed in all of these lenses.
[0033]
Next, using this lens, a light emitting semiconductor chip or the like is accommodated in the light emitter housing member, and after connection, a liquid sealing resin material is filled in the light emitter housing member, and the lens is surface tensioned on the sealing resin material. By placing the convex surface formed by the step toward the sealing resin material side and curing the sealing resin material by heating or the like, the lens is integrally bonded on the sealing material as shown in FIG. A chip-type light emitting diode was manufactured. 100 such chip-type light emitting diodes were manufactured, but none of them was sufficiently free from residual bubbles that scattered or scattered light from the light emitting semiconductor chip between the lens and the sealing material. The brightness was high.
[0034]
【The invention's effect】
As described above, according to the present invention, a semiconductor optical having a convex surface that functions as a condensing lens and that allows bubbles between the lens and the sealing resin material to escape and avoids remaining bubbles. Resin lenses for elements can be manufactured with good productivity without burrs [Brief description of the drawings]
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a view showing an example of a mold used in a manufacturing method according to the present invention, (A) is a perspective view, (B) is a plan view, and (C) is an XX ′ line in (B). FIG.
FIG. 2 is a cross-sectional view showing another example of a mold used in the manufacturing method according to the present invention.
FIG. 3 is an explanatory diagram illustrating a process of manufacturing a lens by a manufacturing method according to the present invention.
4 is a view showing an example of a lens manufactured by the manufacturing method according to the present invention, which is manufactured using the mold shown in FIG. 1, (A) is a perspective view, (B). Is a plan view, (C) is a cross-sectional view taken along line YY ′ of (B), and (D) is a perspective view of a state in which the top and bottom of (A) is returned.
FIG. 5 is a sectional view showing a chip-type light emitting diode, showing an example of a semiconductor optical element using a lens manufactured by the manufacturing method according to the present invention.
FIG. 6 is an explanatory diagram showing a process of manufacturing a chip-type light emitting diode using a lens manufactured by the manufacturing method according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Lens 11, 13 Convex surface 2 Mold 21 Cavity recessed part 211 Disc-shaped recessed part 212 Cross-sectional arc-shaped recessed part 3 Lens resin material 31 Droplet 311 Convex surface

Claims (5)

A resin for a semiconductor optical element that is placed on a liquid sealing resin material for sealing a semiconductor optical element, and is used by being integrated with the sealing material that is a cured product by curing the sealing resin material A method for manufacturing a lens, the method comprising: forming a cavity concave portion having a concave cross-section having a concave surface for forming a convex surface as a condensing surface of the lens in a mold; and providing a liquid lens resin material in the cavity concave portion The semiconductor optical material is filled with the lens resin material so as to form a convex droplet by the surface tension above the cavity recess, and then the lens resin material droplet is heated and cured. Manufacturing method of resin lens for element. 2. The resin lens for a semiconductor optical element according to claim 1, wherein the cavity concave portion is formed in a shape including a disc-shaped concave portion and a circular arc-shaped concave portion formed in a central lower portion thereof. Method. The method for producing a resin lens for a semiconductor optical element according to claim 1, wherein the resin material for a lens is a silicone resin composition. 4. The method for producing a resin lens for a semiconductor optical element according to claim 1, wherein the semiconductor optical element is a light emitting diode. 5. The method for producing a resin lens for a semiconductor optical element according to claim 4, wherein the light-emitting diode is a chip-type light-emitting diode.

Images