JP2011181870A - Glass-sealed type light emitting diode device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem wherein a light emitting element shifts from an optical axis when a lead frame mounted with the light emitting element is sealed in a glass tube. <P>SOLUTION: A resin-made guide part is formed by insert molding under an element mounting part of the lead frame. The resin-made guide part has a rib in its periphery and comes into contact with an inner wall of a hollow glass part. Thus, the relative position of the lead frame to the hollow glass part is fixed throughout sealing operation to suppress an axis shifting. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a light emitting diode device. More specifically, the present invention relates to a suitable technical improvement in sealing a light emitting diode element with glass.

  A light-emitting diode is a type of optical semiconductor element that emits infrared, visible, ultraviolet light, and the like by injecting a current between junctions of a p-type semiconductor layer and an n-type semiconductor layer. Such a light emitting diode device generally has a structure in which a light emitting diode element and a wire or lead frame electrically connected thereto are covered with a resin and protected.

  In recent years, it has been pointed out that there is a problem with the structure in which the periphery of the light emitting diode element is covered with a sealing resin as the light emission wavelength of the light emitting diode becomes shorter, the demand for higher output and higher reliability increases. It has become. If the resin is continuously exposed to short wavelength light for a long time, the sealing resin deteriorates and the initially transparent resin turns yellow or black. As a result, light emission is blocked by the opaque resin, and the light emission intensity of the light-emitting diode device decreases in a time much shorter than the originally expected life.

  Furthermore, the sealing resin cannot block moisture so much, and the light emitting diode device used under high humidity conditions cannot prevent the sealed light emitting diode element itself from deteriorating.

  In order to solve these problems, Patent Document 1 proposes a sealing structure of a light emitting diode device in which resin is replaced with glass and a manufacturing method thereof.

  In the manufacturing method of such a document, first, one end of a glass tube is formed into a substantially hemispherical shape, and then a pair of lead frames bound by glass beads are inserted from the opening side of the other end, and then the glass tube and the glass beads are joined. It is heated and fused with a burner. By this manufacturing method, the light emitting diode element fixed in the shape of a lead frame is hermetically sealed with a glass tube and glass beads.

JP 2004-071771 A

  When the above manufacturing method is actually applied, there is a problem that the optical axis of the light emitting diode element is shifted from the axis of the glass tube. This problem will be described with reference to FIG.

  FIG. 4 shows a process of sealing a lead frame having a light emitting diode element fixed thereon by fusing a glass tube sealed at one end and a glass bead fixed to the lead frame. In the step (a), the lead frame is inserted into a glass tube, heated by applying a burner to the side wall of the glass tube below the glass bead and temporarily fixed. In the step (b), a burner is applied from the side wall of the glass tube to the position of the temporarily fixed glass bead, and the glass bead and the glass tube are heated and fused. In step (c), the remaining portion below the glass tube is removed to complete a glass-sealed light emitting diode device.

  Here, both of the temporary fixing in the step (a) and the fusion in the step (b) tend to cause a deviation between the optical axis of the light emitting diode element and the axis of the glass tube during the step. This is because no measures are taken to fix the relative position of the lead frame to the glass tube throughout this process. For this reason, particularly when mass production is performed, the directional characteristics of each product vary, which is a problem.

  The present invention has been made with the intention of solving the above problems. That is, the light-emitting diode device according to the present invention is such that the periphery of the light-emitting diode element fixed to the element installation part at the tip of the lead frame is covered with a hollow glass part, and in particular, on the inner wall of the hollow glass part below the element installation part. A resin guide portion is formed so as to be in contact with each other. Furthermore, the glass mount for fusing with the lower part of the hollow glass part and sealing in the hollow glass part takes a predetermined distance between the part in contact with the lead frame and the fused part. .

  Due to the introduction of the resin guide portion, the lead frame is fixed relatively to the hollow glass portion, so that the deviation of the light emitting diode element from the axis of the hollow glass portion is suppressed. As a result, variation in directional characteristics from product to product was reduced, and yield was improved. In addition, the introduction of the predetermined glass mount structure has improved the workability when the resin guide portion is formed by the insert molding method, and has increased the mass productivity.

1 is an example of a structure of a light emitting diode device according to the present invention. It is the schematic which looked at the structure of the light emitting diode apparatus by this invention from the top. It is a figure which shows the manufacturing method of the light emitting diode apparatus by this invention. It is a figure which shows a prior art example and its problem.

  The present invention will be described below with reference to the drawings. For the sake of convenience, the optical axis direction of the light emitting diode device in the figure will be described as “upper” and the opposite side as “lower”.

  FIG. 1 is a schematic diagram of a light emitting diode device according to the present invention. The light emitting diode element 1 is fixed on and electrically connected to the element mounting portion 3 at one end of the pair of lead frames 2. In addition, the lead 4 is electrically connected to the other lead frame. A resin guide portion 5 is formed below the element placement portion 3 to fix the relative positions of the pair of lead frames 2. Further, the resin guide portion 5 is in contact with the hollow glass portion 6 by a rib 11 described later, and maintains the relative positional relationship between the lead frame 2 and the hollow glass portion 6.

  The hollow glass portion 6 has a structure in which the portion for housing the light emitting diode element 1 is hollow, and seals the light emitting diode element 1, the element placement portion 3, and the resin guide portion 5 together with the glass mount 7. The glass mount 7 is in close contact with the hollow glass portion 6 by the fused portion 8, and is penetrated by the lead frame 2 through the through portion 9 at a position below the resin guide portion 5. A space between the lead frame 2 and the glass mount 7 is hermetically sealed. Further, the penetrating portion 9 and the fused portion 8 are separated to some extent by a cylindrical structure 10.

  With reference to FIG. FIG. 2 is a top view of the light emitting diode device of FIG. For convenience, the upper portion of the hollow glass portion 6 and the wire 4 are not shown. Ribs 11 protruding from the resin guide portion 5 are in contact with the inner wall of the hollow glass portion 6. This prevents the light emitting diode element 1 from being displaced from the optical axis.

  Next, a method for manufacturing a light emitting diode device according to the present invention will be described. FIG. 3A shows the lead frame 2 with a glass mount 7 attached thereto. The glass mount 7 can be attached by a known glass processing step in which the tip of a glass tube having a predetermined length is softened with a burner and attached to the lead frame 2. Alternatively, after the bead is softened with a burner and the through portion 9 is formed in the lead frame 2, the tip of the glass mount 7 may be softened with the burner and welded to the through portion 9.

  Next, the structure of FIG. 3A is put into a mold, and insert molding is performed as shown in FIG. By this step, the resin guide portion 5 is formed as shown in FIG. The light-emitting diode element 1 is fixed to the element mounting portion 3 on this, and is electrically connected to the lead frame 2.

  Finally, the light emitting diode element 1 and the like are covered with the hollow glass portion 6, and the lower portion of the hollow glass portion 6 and the lower portion of the glass mount 7 are heated and fused by a burner to form the fused portion 8. Thereby, the light emitting diode element 1 and the like are sealed.

  The reason why the resin guide portion 5 is performed by insert molding is that it is possible to mass-produce a stable structure with small shape variation. In particular, since the processing variation of the glass mount 7 tends to be larger than that in the case of insert molding, the introduction of the resin guide portion 5 stabilizes the shape and has the effect of facilitating handling. In addition, if a plurality of molds connected by a runner are used, handling by an automatic machine is possible thereafter, and further improvement in mass productivity can be expected.

  The glass mount 7 includes a cylindrical structure 10 between the fused portion 8 and the through portion 9. The reason for this configuration is that it is easy to handle at the time of insert molding and that heat at the time of forming the fused portion 8 is considered not to affect the light emitting diode element 1 through the glass mount 7 and the lead frame 2. Although the length of the cylindrical structure 10 depends on the thermal conductivity of the glass mount 7, for example, when soft glass is used, it may be 3 mm or more.

DESCRIPTION OF SYMBOLS 1 Light emitting diode element 2 Lead frame 3 Element mounting part 4 Wire 5 Resin guide part 6 Hollow glass part 7 Glass mount 8 Fusing part 9 Through part 10 Cylindrical structure 11 Rib

Claims (2)

A lead frame;
An element installation portion formed at the upper end of the lead frame;
A light emitting diode element fixed to the element installation portion and electrically connected;
The light emitting diode element, the element installation part, a hollow glass part covering a part of the lead frame around these,
A glass mount that penetrates the lead frame and is fused to the lower part of the hollow glass portion;
A resin guide portion above the glass mount of the lead frame and fixed immediately below the element installation portion, and in contact with the inner wall of the hollow glass portion;
In the glass mount, the position where the lead frame penetrates is closer to the element installation part than the position fused with the lower part of the hollow glass part,
The position where the lead frame penetrates and the lower part of the glass mount fused to the lower part of the hollow glass part are connected by a substantially cylindrical structure,
A light emitting diode device characterized by the above. A first step of forming a glass mount below the element installation part at the upper end of the lead frame;
A second step of forming a resin guide portion below the element mounting portion and above the glass mount by insert molding;
A third step of fixing and electrically connecting the light emitting diode element to the element installation portion;
The light emitting diode element, the element installation part, and a part of the lead frame in the vicinity thereof are inserted into a hollow glass part, and the lower part of the hollow glass part and the lower part of the glass mount are fused and sealed. And the process of
Including
The portion in contact with the lead frame of the glass mount and the lower portion of the glass mount are connected with a substantially cylindrical structure,
A method for manufacturing a light-emitting diode device.

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