JP2865081B2 - Method for forming protective coating layer of diode element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a protective coating layer such as a junction coating resin (JCR) on a coaxial diode element having a pair of rod-shaped leads.

[0002]

2. Description of the Related Art As shown in FIG. 1, a junction coating resin (JCR) is generally provided on a side surface of a diode chip 5 fixed between first and second rod-shaped leads 1 and 2 arranged coaxially with solders 3 and 4. It is known to provide a protective resin coating layer 6 referred to as). The bar-shaped leads 1 and 2 have flange-shaped heads 1b and 2b at one end of bar-shaped portions 1a and 2a extending linearly, and a diode chip 5 is arranged between the heads 1b and 2b. The diode chip 5 is a well-known one having a silicon P-type semiconductor region, a silicon N-type semiconductor region, an anode electrode, and a cathode electrode, and has a diameter smaller than the diameter of the flange-shaped heads 1b, 2b.

[0003]

Conventionally, when forming the protective resin coating layer 6, a fluid silicone resin, for example, is potted or dropped on the side surface of the diode chip 5. However, the protective resin coating layer 6
Is formed, when the diode elements are mass-produced, not only the thickness of the protective resin coating layer 6 varies, but also the productivity is poor.

Accordingly, an object of the present invention is to provide a method capable of improving the productivity of a protective coating layer covering the side surface of a diode chip.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a liquid crystal protection device in which a diode chip is fixed between first and second rod-shaped leads on a side surface of the diode chip. A method for forming a protective coating layer by adhering a substance, comprising a groove on an upper surface capable of accommodating a liquid protective substance, wherein the surface tension of the liquid protective substance is greater than the height of an edge of the groove. A liquid protective material carrier member in which the width of the groove is set so as to allow high attachment, and the length of the groove is set to be equal to or greater than the distance between the at least two diode elements arranged in parallel with each other. And a container containing a liquid protective substance so that the liquid protective substance transport member can be immersed therein, and the liquid protective substance transport member is immersed in the liquid protective substance of the container. Then, the liquid protective substance is accommodated in the groove, and the liquid protective substance conveying member is moved from the inside of the container to near the side surface of the diode chip of the at least two diode elements. The liquid protective material contained in the groove so as to increase the height of the at least two diode elements.
A method for forming a protective coating layer on a diode element, wherein the protective coating layer is simultaneously formed on the at least two diode elements by contacting the side surfaces of the diode chip. In addition, as described in claim 2, the liquid protective material can be attached while moving the diode element.

[0006]

According to the invention, the liquid protective material can be stably and uniformly supplied to the side surface of the diode chip. Further, according to the first aspect of the present invention, it is possible to simultaneously attach a liquid protective substance to a plurality of diode elements, thereby improving productivity.
According to the second aspect of the present invention, since the liquid protective substance is attached while moving the diode element, not only the productivity is improved, but also the diode chip is used even if the liquid protective substance has a relatively high viscosity. Can be uniformly attached to the side surfaces of

[0007]

Next, a method for forming a protective coating layer of a diode element according to an embodiment of the present invention will be described with reference to FIGS. In the present embodiment, the diode element 7 for forming the protective coating layer is made up of the first and second diodes as apparent from FIGS.
The diode chip 5 is fixed between the flange-shaped heads 1b and 2b of the rod-shaped leads 1 and 2 by solders 3 and 4,
As shown in FIG. 1, a protective resin layer 6 is provided on a side surface of the chip 5.

An apparatus for forming the protective resin coating layer 6 according to the present embodiment includes a transfer device 8 for a diode element 7 and
It comprises a liquid protective resin carrying member 9, a vertical drive device 10 for the carrying member 9, and a bath or container 11 containing the liquid protective resin 6a.

The diode element moving device 8 comprises a plurality of pairs of lead supports 12 for supporting the rod portions 1a and 2a of the first and second rod leads 1 and 2, and the lead support 12
, And a belt driving device 14. The lead support 12 has a rod-like portion 1a of the lead,
It has a U-shaped recess 15 for receiving 2a. The belt 13 is driven intermittently or continuously by a driving device 14.

The liquid protective resin conveying member 9 is formed in a plate shape, has a V-shaped groove 16 in cross section on the upper surface thereof, and has inclined surfaces 17 and 18 outside the edge of the groove 16. . That is, a valley formed by arranging the two triangular protrusions side by side forms the V-shaped groove 16. The distance between the edges on both sides of the V-shaped groove 16, that is, the width of the entrance of the groove 16 substantially corresponds to the thickness of the diode chip 5. It is desirable to set the interval between the edges on both sides of the groove 16 to be about 0.5 to 2 times the thickness of the diode chip 5, and more desirably the interval between the pair of heads 1b and 2b. That is,
It is desirable to set the width of the entrance of the groove 16 so that the liquid protective resin 6a can be accommodated in a state of being protruded higher than both edges of the groove 16 by the surface tension of the liquid protective resin 6a. The longitudinal direction of the upper surface of the liquid protective resin conveying member 9, that is, the direction in which the groove 16 extends, is a rod-shaped lead of the diode element 7.
Are perpendicular to the direction in which the nodes 1 and 2 extend. The length L of the upper surface in the longitudinal direction is set to be longer than the mutual distance between at least two diode elements 7 arranged in parallel with each other and transported by the belt 13. In FIG. 3, two diode elements 7 are included in the range of the length L of the upper surface of the liquid protective resin conveying member 9;
The conveying member 9 can be formed so that about a unit is included in the length L of the upper surface.

The container 11 has a box shape with an open top, and is formed to be deeper than the height of the liquid protective resin transporting member 9 so that the silicon resin can be immersed in the entire liquid protective resin transporting member 9. A liquid protective material 6a made of resin JCR is contained.

In order to move the liquid protective resin conveying member 9 from the inside of the container 11 to the vicinity of the diode chip 5, the conveying member 9 is provided with a pair of crank-shaped arms 19, 20. , A lifting device, that is, a vertical driving device 10 is connected.

When applying the liquid protective resin 6a to the diode chip 5 of the diode element 7, the JCR
The liquid protective resin 6a as described above is put, and the whole including the upper surface of the transport member 9 is immersed in the liquid protective resin 6a.
As a result, the carrying member 9 is raised toward the diode chip 5 of the diode element 7. Since the carrying member 9 has the groove 16 on its upper surface even when it goes out of the container 11, the liquid protective resin 6a is accommodated in this groove. The accommodation state of the liquid protective resin 6a in the groove is a state in which the liquid protective resin 6a rises from both edges of the groove 16 due to the surface tension of the liquid protective resin 6a, that is, projects. In this embodiment, a plurality of diode elements 7 are arranged in parallel with each other at the same time when the transport member 9 is raised, and are moved in the longitudinal direction of the groove 16 by the belt 13. The groove 16 is formed longitudinally, and the position in the left-right direction in FIG. 2 is set in advance so as to correspond to the diode chip 5 of the diode element 7. Therefore, even if the positioning of the groove 16 with respect to the diode chip 5 in the longitudinal direction is not particularly performed, when the carrying member 9 is raised, the groove 16 is formed with a plurality of diodes.
The groove 16 is opposed to the diode chip 5 of the diode element 7 at the same time.
The liquid protective resin 6a housed in a protruding state can be brought into contact with a plurality of diode chips 5 at the same time.
At this time, since the diode element 7 is transferred in the longitudinal direction of the groove 16, the operation of pressing the liquid protective resin 6a attached to the diode chip 5 by the liquid protective resin 6a remaining in the groove 16 occurs. The liquid protective resin 6a is applied with good uniformity to the entire periphery of the side surface of the diode chip 5. Even when the viscosity of the liquid protective resin 6a is relatively high, since the liquid protective resin 6a has fluidity, the liquid protective resin 6a
a is attached, this flow causes the diode chip 5
Is covered with the liquid protective resin 6a.

When the application of the liquid protective resin 6a to the diode chip 5 is completed, the transport member 9 is immersed again in the liquid protective resin 6a in the container 11 to apply the liquid protective resin 6a to the next diode element. Do.

The liquid protective resin 6a applied to the diode chip 5 is cured by heating, for example, to form a protective resin coating layer 6 as shown in FIG. The hardening of the protective resin 6a is performed while transferring the diode element 7 by the transfer device 8.

As is apparent from the above, this embodiment has the following advantages. (A) Since the liquid protective resin 6a is accommodated in the groove 16 formed in the longitudinal direction and the liquid protective resin 6a is simultaneously attached to the side surfaces of the plurality of diode chips 5, the productivity of forming the protective resin layer 6 is improved. . (B) Since the liquid protective resin layer 6a is adhered to the diode chip 5 while transferring the diode element 7, the protective resin 6 having a relatively high viscosity can be satisfactorily adhered. (C) Since the diode chip 5 is disposed between the heads 1b and 2b which are larger than the diameter of the portion of the diode chip 5 where the PN junction is provided, the pair of heads 1b and 2b
A recess is formed between b. Therefore, the liquid protective resin 6a adheres favorably to the side surface of the diode chip 5.

[0017]

[Modifications] The present invention is not limited to the above-described embodiment, and for example, the following modifications are possible. (1) As shown by a dotted line in FIG. 2, a motor M for rotating the diode element 7 is provided, and the liquid protective resin 6a can be supplied to the side surface of the diode chip 5 while rotating the diode element 7. (2) The liquid protective resin 6a can be applied while intermittently transferring the plurality of diode elements 7. (3) The diode chip 5 can be a stacked diode chip in which a plurality of diode chips are stacked.
Further, the side surface of the diode chip 5 can be formed as an inclined surface for increasing the breakdown voltage. (4) The groove 16 can be made concave. (5) Stoppage of the liquid protective resin 6a can be provided at both ends of the groove 16 in the longitudinal direction.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a diode element.

FIG. 2 is a cross-sectional view of a portion corresponding to line BB in FIG. 3, which basically shows the protective resin layer forming apparatus according to the embodiment of the present invention.

3 is a cross-sectional view of a portion corresponding to line AA of the protective resin layer forming device of FIG.

[Explanation of symbols]

 1, 2 rod-shaped lead 5 diode chip 6a liquid protective resin 9 liquid protective resin carrying member 16 groove

Continuation of the front page (72) Inventor Masayoshi Karui 3-6-3 Kitano, Niiza-shi, Saitama Sanken Electric Co., Ltd. (56) References JP-A-48-8059 (JP, A) JP-A-49-31279 (JP, A) JP-A-61-71638 (JP, A) JP-A 55-96648 (JP, U) JP-A 60-76036 (JP, U) JP-A 60-118208 (JP, U) ( 58) Surveyed field (Int.Cl. ⁶ , DB name) H01L 21/56

Claims (2)

(57) [Claims] 1. A method of forming a protective coating layer by attaching a liquid protective material to a side surface of a diode chip of a diode element in which the diode chip is fixed between first and second rod-shaped leads. Having a groove on the top surface capable of containing a liquid protective substance,
The width of the groove is set so that the liquid protective substance can be attached higher than the height of the edge of the groove by the surface tension, and the distance between the at least two diode elements arranged in parallel with each other. As described above, a liquid protective substance transport member having the length of the groove set therein, and a container containing a liquid protective substance so that the liquid protective substance transport member can be immersed, are prepared. Immersing the liquid protective substance transport member in a protective substance, accommodating the liquid protective substance in the groove, and placing the liquid protective substance transport member in the container from the side of the diode chip of the at least two diode elements. Moving the liquid protective material contained in the groove so as to be higher than the edge of the groove by moving closer to the die of the at least two diode elements; - each brought into contact with the Dochippu aspect, the at least two diodes - diode and forming de element the protective coating layer at the same time - de protective coating layer forming method of the element. 2. A method for forming a protective coating layer by attaching a liquid protective material to a side surface of a diode chip of a diode element in which the diode chip is fixed between first and second rod-shaped leads. Having a groove on the top surface capable of containing a liquid protective substance,
Immersing the liquid protective substance transporting member having the width of the groove set so that the liquid protective substance can be attached higher than the height of the edge of the groove by the surface tension; and the liquid protective substance transporting member. A container containing a liquid protective substance so that the first and second rod-shaped leads are horizontal, and the diode element is disposed above the container so that the first and second rod-shaped leads are horizontal. The liquid protective substance carrier is immersed in the liquid protective substance to accommodate the liquid protective substance in the groove, and the liquid protective substance carrier is moved from the inside of the container to a side of a diode chip of the diode element. Moving the liquid protective material contained in the groove so as to be higher than the edge of the groove to contact the side surface of the diode chip of the diode element; Protective coating layer forming method of de elements - diode, wherein forming the protective coating layer by moving the de element in a direction in which the groove extends.