JPH1044180A - Transfer resin sealing method and resin sealing mold device used for the method - Google Patents

Abstract

(57) [Summary] The object of the present invention is to provide transistors, LEDs, and ICs.
Another object of the present invention is to eliminate the generation of unnecessary resin burrs between the sealed component and the mold in the production of the resin-sealed electronic component. The present invention provides a transfer resin sealing method in which a cavity into which a resin is injected is formed with a base material sandwiched between upper and lower molds, and a sealing resin is injected into the cavity from a predetermined cull through a runner communicating with the cavity. In the stopping method,
An elastic material such as rubber is protruded and embedded on either one of the upper and lower mold parts, along the runner, and on the resin injection end side of the cavity. The molten resin is injected into the cavity through a runner from the beginning.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a light emitting diode (L)
The present invention relates to a transfer resin sealing method for a resin-sealed electronic component such as an individual component such as an ED) or a transistor or a semiconductor integrated circuit (IC) device, and a resin-sealing mold device used for the same. The present invention relates to a sealing technique for suppressing the generation of burrs.

[0002]

2. Description of the Related Art For this type of transfer mold, for example, a mold shown in FIGS. 6 and 8 has been conventionally used. This mold is for resin-sealing molding of the chip-type LED component shown in FIG. Chip type LED of the same figure
Reference numeral 10 denotes a substrate 7 such as a glass epoxy resin substrate or a ceramic, as disclosed in Japanese Patent Application Laid-Open No. 6-5926.
A pair of lead electrodes 72a and 72b are formed on the upper surface of the LED chip 1, an LED element 73 is bonded to one of the lead electrodes 72a, and a wire bonding is performed between the LED element 73 and the other lead electrode 72b by a gold wire 74 or the like. Have been. The LED element 73, the gold wire 74, and the like are covered with a square pyramid-shaped mold portion 75 made of a translucent synthetic resin or the like.
Each of the lead electrodes 72a and 72b is
Are extended to both ends of the substrate 71 to form terminal electrodes 76 and 77.

[0003] A resin sealing process of the chip type LED 70 by a mold will be described with reference to FIGS. 6 and 8. FIG. 8 is a sectional view taken along the line AA of FIG. The insulating substrate 23 is a substrate material for forming a large number of chip components. The electrode patterns of the lead electrodes 72a and 72b shown in FIG. 7 are formed in advance on this substrate, and the LED patterns are formed on the electrode patterns.
A plurality of elements 73 are mounted separately by a bonding process. Then, in the molding process, the insulating substrate 2
3 are placed on the lower mold 22, and the upper mold 31 is clamped (clamped) from above, and each LED element mounted in a row on the substrate 23 by being sandwiched between the upper and lower molds. Is formed. 25 is the substrate 2
3 is a long slit that separates the cavities from each other. In addition, resin pellets are provided on a center block 30 of a mold for transfer molding.
, From which the molten resin is supplied to each cavity through runners 21 and 24. After the molding process,
By cutting the elongated mold portion corresponding to the cavity 26 together with the substrate for each LED element unit, it is divided into chip components as shown in FIG. In addition,
This mold is constituted by a detachable chase block in which individual mold members are incorporated as a total of four cavity areas communicating with the cull 20 and the runner 21.

[0004]

However, such a transfer mold has a problem that when resin burrs are generated due to resin leakage from a parting surface of a mold or the like, it takes a lot of trouble to remove the resin burrs. Therefore, in general, the upper and lower molds are clamped with a certain pressure so that the parting surfaces are in close contact with each other so as not to generate burrs.

However, when a substrate or a lead frame is sandwiched and molded, clamping adjustment is performed by preferentially applying the parting surface of the mold to the substrate or the frame so that thin burrs do not remain on the substrate or the frame. Because of the necessity, a small gap is likely to be formed between the parting surfaces of the center block 30 and the runner 21 other than the cavity, and the resin leaks therefrom, causing resin burrs. In particular, if the material of the substrate or frame has dimensional variations in the thickness direction, when placed in multiple cavity areas, a gap between the parting surfaces between the cavity areas will occur, and it will be resolved even if the clamping pressure is increased could not. In particular, a thermosetting synthetic resin is used for the resin sealing mold of the above-mentioned chip-type LED component. However, when a translucent epoxy resin material containing no filler is used, the thickness of the substrate is 0.01 m / m2. Even if there is a degree of dimensional variation, a low-viscosity resin material spreads across the gap and not only forms a resin burr 28 near the end of the cavity but also a thin resin burr 27 near the runner 21 as shown by hatching in FIG.
And 29, making up almost the entire surface of the mold. Furthermore, when the cull 20 is worn, a gap is also formed in the vicinity thereof, so that it is necessary to frequently replace the mold parts.

As a conventional countermeasure against resin burr, Japanese Patent Laid-Open No.
JP-A-175732 and JP-A-58-110048 disclose a method of embedding a synthetic rubber material in a groove around a cavity and sealing it with a mold clamp.
However, conventionally, it has only been possible to prevent resin leakage from the periphery of the cavity, and it has been difficult to prevent the resin from reaching the entire parting surface.

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, it is an object of the present invention to provide a transfer mold in which a substrate or a frame material is sandwiched between molds and resin is injected from a cull through a runner into a cavity. An object of the present invention is to provide a transfer resin sealing method capable of suppressing the occurrence of burrs and saving the time and effort for deburring, and a resin sealing mold device using the same.

[0008]

According to a first aspect of the present invention, there is provided a transfer resin sealing method, comprising: a step of forming a cavity into which a resin is injected while a base material is sandwiched between upper and lower molds; In a transfer resin sealing method of forming and injecting a sealing resin into the cavity through a runner communicating with the cavity from a predetermined resin injection port, in one of the upper and lower mold parting surfaces, and in the runner Then, an elastic material is protruded and buried on the resin injection end side of the cavity, and the upper and lower molds are clamped to inject molten resin into the cavity from the resin injection port through the runner. I do.

A resin sealing mold device according to a second aspect of the present invention is a mold device used in the transfer resin sealing method according to the first aspect, wherein one of the upper and lower molds has a parting surface. The elastic material is buried in the first groove formed along the runner and in the second groove provided on the resin injection terminal side of the cavity by protruding.

Further, the resin-sealing mold device according to the invention of claim 3 is formed on one of the parting surfaces of the upper and lower molds and communicates with the cavity at the resin injection end side of the cavity. A concave portion is provided, and the second groove is formed near the outer periphery of the concave portion. In the present invention, for the base material, for example, a lead frame or a glass epoxy substrate made of an iron-nickel alloy material or the like can be used.

The resin encapsulation method according to the present invention uses LE
D and other individual components such as transistors, or DIP (Dual Inner Packag)
e) a pin insertion type electronic component represented by
QFP (Quad Flat Package) used in C etc.
Etc. can be applied to the surface mounting type.

[0012]

According to the present invention, not only the resin injection end of the cavity but also the sealing means made of an elastic material is provided along the runner, so that even if resin leakage occurs on the entire parting surface, the sealing means is located outside the vicinity of the runner and the cavity. The transfer molding process can be simplified without the need for time-consuming resin burr removal work.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a transfer mold used for manufacturing a chip-type LED of this embodiment, FIG. 2 shows a main part of the mold, and FIG. 3 shows a cross section taken along line BB of FIG.
A cavity area 3 for four sections communicating with a runner 5 branched in four directions from the cull 4 is provided in the lower mold 1. The four cavity areas 3 are removably attached to the lower mold 1 together with the center block 10 provided with the cull 4, and the lower mold 1 and the upper mold slidable along the column 2. 14 form a chase block. Runners 5 and 6 and cavity 1
5 is formed on the upper mold 14 side. This example shows a step of transfer-molding the chip-type LED shown in FIG. The insulating substrate 7 is made of glass epoxy resin, ceramic, or the like, and has a plurality of LED elements 18 mounted in a row by a chip bonding process in advance. 1
7 are arranged in each row. Transfer molding is performed by one cull 4 for eight substrates 7 as a whole mold, but two cavities are formed in each cavity area 3 for a runner 6 branched from one runner 5 into two. 7
Is placed on the lower mold 1.

Then, as shown in FIG. 3, after the substrate 7 is placed on the lower mold 1, the upper mold 14 is clamped from above and clamped between the upper and lower molds. ,
An elongated cavity 15 is formed to cover each LED element row mounted in a row on the substrate 7. The runners 5 and 6 and the cavity 15 are recessed in the parting surface of the upper mold 14. At the end of each cavity 15, a resin reservoir 12 is provided as a long recess corresponding to the entire width of the substrate 7 on the parting surface of the upper mold 14 via a communication path 16. One pair of cavities 15 is runner 6 at one end.
And a plurality of stages are connected in parallel. The molten resin from the cavity 4 passes through the runner 5 and the runner 6 to each cavity 1.
After being injected into the cavity 5, the resin reaches the resin reservoir 12 provided at the end of each cavity 15.

Next, a structure for preventing resin leakage of a mold according to this embodiment will be described. The lower mold 1 has a groove 19 having a rectangular cross section shown in FIG. 4 around the cull 4, along the runner 5 communicating with the cull 4 and the runner 6 communicating with the cavity 15, and further near the outer periphery of the resin reservoir 12. Are formed.
Then, the elastic members 8, 9, 11, and 13 are fitted into the grooves 19 in such a manner that they protrude slightly, and almost the entire amount is accommodated in the grooves by clamping the upper and lower dies, and the cull 4, the runners 5 and 6,
And sealing means for sealing each periphery of the resin reservoir 12. That is, these sealing means include a substantially U-shaped elastic member 8 fitted to the outside of the resin reservoir 12 corresponding to the end of the resin injection, an elastic member 9 fitted along both sides of the runner 5,
An elastic member 13 is provided at the center of the runner 6 branched from the runner 5 in a T-shape and between the two substrates 7. The elastic member 8 corresponds to the second groove in the invention of claim 2, and the first groove in the claim corresponds to the elastic members 9 and 11.
The elastic material 13 is for sealing the central portion of the runner 6 so that resin leakage does not spread to the parting surface between the substrates 7. The elastic material is preferably a heat-resistant material having a curing temperature characteristic higher than the melting temperature of the sealing resin, that is, the mold temperature. The transparent or translucent LED sealing without filler used in the present embodiment is used. Since the thermosetting epoxy resin has a melting temperature of about 150 ° C., a synthetic resin such as silicone rubber or urethane may be used. IC
For the sealing resin of the package, a material that can withstand a high temperature of 180 ° C. to 230 ° C. or more is used. For example, a silicone rubber round material having a diameter of 4φ is embedded in the groove 19 so as to protrude by about 0.5 m / m, and the mold is clamped so that a clearance (gap) of about 0.1 to 0.2 m / m is formed by pressing the upper mold 14. When this is done, the resin burr that has flowed out around the runner 5 is blocked by the silicone rubber round material, and the burr that has flowed out slightly has a thickness that is easy to release. The shape of the elastic material may be a round bar or a prism, and the cross-sectional shape of the groove 19 may be a polygon other than a rectangle, a hemisphere, or the like. When the groove forming position is set with an interval such that burrs smaller than the vicinity of the runner remain, the molded product can be taken out smoothly at the time of mold release. Further, in this embodiment, the rubber material is used to urge the upper and lower molds (1, 14) in the direction opposite to the pressing direction when the molds are clamped. However, as shown in FIG. A metal bar member 50 having a shaft portion 52 that can be slid up and down is fitted into the formed groove 53, and a spring member 52 is attached to the shaft portion 52 to urge the spring returning force to the upper mold 14 during mold clamping. You may do so.

In the resin-sealing mold apparatus of the present embodiment having the above-described resin leakage prevention structure, first, with the upper and lower molds (1, 14) clamped as shown in FIG. The molten resin is supplied to the cull 20, the molten resin is supplied to the cavities 15 through the runners 5 and 6 therefrom, and further fed out to the resin reservoir 12 through the communication path 16 to perform the transfer molding step. After the resin is injected, the mold is formed by heating at a high temperature, the mold is opened, and ejector pins (not shown) are pushed out from the upper mold 14 to push up the resin material portions such as the runners 5 and 6. The mold product is separated from the mold and taken out. The individual LED parts shown in FIG. 7 are obtained by dividing the elongated molded product integrally formed on each substrate 7 through a cutting step (not shown).

In this embodiment, at the time of mold clamping, a sealing means comprising elastic members 8, 9, 11 and 13 provided around the resin 4, the runners 5 and 6, and the resin reservoir 12 at the time of the above resin injection is used. Even if a clearance (gap) is formed between the dies, diffusion of the leaked resin can be prevented, and troublesome cleaning work of the dies can be omitted.

[Brief description of the drawings]

FIG. 1 is a plan view of a mold used in an embodiment of the present invention.

FIG. 2 is an enlarged plan view of a main part of the mold of FIG.

FIG. 3 is a sectional view taken along the line BB of FIG. 2;

FIG. 4 is a sectional view showing an attached state of an elastic material used for the mold of FIG. 1;

FIG. 5 is a cross-sectional view showing another example of the elastic material of the present invention.

FIG. 6 is a plan view showing a conventional mold.

FIG. 7 is an external perspective view showing a chip-type LED.

FIG. 8 is a sectional view taken along the line AA of FIG. 6;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 lower mold 3 cavity area 4 cull 5 runner 6 runner 7 insulating substrate 8 elastic material 9 elastic material 11 elastic material 12 resin reservoir 13 elastic material 14 upper mold 15 cavity 19 groove

Continued on the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical indication // B29K 101: 10 B29L 31:34

Claims (3)

[Claims] 1. A transfer resin for forming a cavity into which a resin is injected with a base material sandwiched between upper and lower molds, and injecting a sealing resin into the cavity through a runner communicating with the cavity from a predetermined resin injection port. In the sealing method, an elastic material is buried on one of the parting surfaces of the upper and lower molds, along the runner, and on the resin injection end side of the cavity so as to protrude, and the upper and lower molds are molded. A transfer resin sealing method, wherein the molten resin is injected into the cavity from the resin inlet through the runner by tightening. 2. A mold device used in the transfer resin sealing method according to claim 1, wherein a first groove formed on one of the parting surfaces of the upper and lower molds and along the runner. The resin sealing mold device is characterized in that the elastic material protrudes and is embedded in a second groove provided on the resin injection terminal side of the cavity. 3. A recess formed on one of the parting surfaces of the upper and lower molds and communicating with the cavity on the resin injection end side of the cavity, wherein the second groove is provided near an outer periphery of the recess. 3. The resin-sealing mold device according to claim 2, wherein: