KR100748241B1 - High brightness led with protective function of electrostatic discharge damage and method of manufacturing the same - Google Patents

Abstract

A high brightness LED and its manufacturing method are provided to prevent the damage of an LED chip by bypassing a reverse current generated due to electrostatic discharge using a parallel connection structure between the LED chip and an electrostatic discharge protecting element. A lead frame(50) is composed of an anode lead(51) and a cathode lead(52). A package(10) is used for holding partially the lead frame and exposing the entire upper surface of the lead frame and a portion of the lower surface to the outside. A fixing member(10a) is used for fixing the anode and cathode leads with each other as one piece. An LED chip(30) is mounted on the exposed upper surface of the lead frame. An electrostatic discharge protection element(40) is mounted on the exposed lower surface of the lead frame. The electrostatic discharge protection element and the LED chip are connected with each other in parallel through a wire. A first molding member(20) is used for protecting the LED chip. A second molding member(70) is used for protecting the electrostatic discharge protection element.

Description

High brightness LED with protective function of electrostatic discharge damage and method of manufacturing the same}

1 is a cross-sectional view showing a high-brightness LED having a built-in protection against electrostatic discharge shock according to the prior art.

Figure 2 is a cross-sectional view showing a high brightness light emitting diode with a built-in protection against the electrostatic discharge shock according to the prior art.

3 is a cross-sectional view showing a high-brightness LED having a built-in protection against electrostatic discharge shock according to an embodiment of the present invention.

FIG. 4 is a schematic diagram illustrating a reverse current prevention circuit of a high brightness light emitting diode having a built-in protection against electrostatic discharge shock shown in FIG. 3.

5A through 5D are cross-sectional views sequentially illustrating a method of manufacturing a high brightness LED having a built-in protection against electrostatic discharge shock according to an embodiment of the present invention.

<Explanation of symbols for main parts of the drawings>

10: package 10a: fixing member

20: first molding material 30: LED chip

40: electrostatic discharge impact protection element 50: lead frame

51: anode lead 52: cathode lead

60: wire 70: second molding material

The present invention relates to a high-brightness light emitting diode having a built-in protection against electrostatic discharge shock and a method of manufacturing the same, and more particularly, to protect the light emitting diode from electrostatic discharge shock, improve the brightness of the light emitting diode, and at the same time, the manufacturing process is simple. The present invention relates to a high brightness light emitting diode having a built-in protection against electric shock and a manufacturing method thereof.

In general, a light emitting diode (LED) is an electronic component that generates a small number of carriers (electrons or holes) injected by using a p-n junction structure of a semiconductor and emits light by recombination thereof. In other words, when a forward voltage is applied to a semiconductor of a specific element, electrons and holes move through the junction of the anode and the cathode and recombine with each other. Release.

Such a light emitting diode can be irradiated with high efficiency light at low voltage, and thus is used in home appliances, remote controls, electronic signs, indicators, and various automation devices.

In particular, according to the trend toward miniaturization and slimming of information and communication devices, various components such as resistors, capacitors, and noise filters are becoming more compact, and surface-mounted diodes are directly mounted on a printed circuit board (PCB). It is made of a device (Surface Mount Device, hereinafter referred to as SMD).

The SMD type LED package is manufactured in a top view and a side view according to its use. Generally, the LED is known to be vulnerable to static electricity or reverse voltage.

Therefore, in order to compensate for the weakness of the light emitting diode, conventionally, a constant voltage diode capable of flowing current in a reverse direction is provided, and such a constant voltage diode is preferably connected to a Zener diode in parallel with an LED chip to efficiently prevent static electricity. To respond.

1 and 2, a high brightness LED having a built-in protection against electrostatic discharge shock according to the prior art will be described in detail.

 1 is a front view showing a high-brightness LED having a built-in protection against electrostatic discharge shock according to the prior art.

Referring to FIG. 1, the constant voltage diode according to the related art includes an LED chip 30 and a zener diode (on the same surface of a lead frame 50 formed of a pair of leads, that is, the anode lead 51 and the cathode lead 52). 40 are mounted side by side, and the LED chip 30 and the electrostatic discharge impact protection device 40 are connected to each other with a wire 60 made of gold (Au) to have a parallel structure. At this time, the electrostatic discharge impact protection device 40 is made of a zener diode.

The zener diode as the electrostatic discharge shock protection device 40 is also called a constant voltage diode, and is one of the semiconductor PN junction diodes, and is a diode manufactured to exhibit operating characteristics in the breakdown region of the PN junction. Used as It is a device that obtains a constant voltage by using Zener recovery phenomenon, and it is a diode that operates with a current of 10 mA at the p-n junction of silicon and obtains a constant voltage of 3 to 12 V depending on the variety.

Therefore, the light emitting diode according to the related art can be connected to the LED chip in parallel by a wire or the like, it is possible to prevent damage by the zener diode even if the reverse current is applied due to static electricity.

Unexplained reference numeral 10 denotes a package formed of a transparent or opaque synthetic resin material, and 20 denotes a molding material for protecting the LED chip.

However, since the Zener diode is mounted together in parallel on the LED chip and the lead frame, the light emitting diode according to the related art needs to have a large lead frame to secure a sufficient area for bonding wires, and thus, a package of the light emitting diode. Since the size of the light emitting diode package is increased, it is difficult to miniaturize the LED package.

In addition, there is a problem in that the light emitted from the LED chip is absorbed or scattered by the zener diodes mounted together in parallel to reduce the luminance of the light emitting diodes.

In order to solve this problem, as shown in Figure 2, a technique for mounting the electrostatic discharge shock protection device 40 on the back of the lead frame is mounted LED chip has been proposed. Figure 2 is a cross-sectional view showing a high brightness light emitting diode with a built-in protection function against the electrostatic discharge shock according to the prior art.

In the conventional light emitting diode shown in FIG. 2, the LED frame 30 and the electrostatic discharge impact protection device 40 are formed in parallel on the lead frame 50, but the lead frame 50 having the LED chip 30 is formed. The electrostatic discharge shock protection device 40 is mounted on the rear surface of the back panel) to protect the light emitting diode from the electrostatic discharge shock and to improve the brightness of the light emitting diode.

However, in the conventional light emitting diode as described above, the electrostatic discharge shock protection device 40 is first mounted on one side of the lead frame, and then, the electrostatic discharge shock protection device 40 is embedded at the same time by using a synthetic resin material. After forming a package in which a part of the rear surface of the lead frame on which is formed) is formed by mounting an LED chip on the exposed lead frame, there is a complicated manufacturing process.

Therefore, the overall manufacturing process of the high-brightness LED having a built-in protection against electrostatic discharge shock is long, and thus there is a problem that the manufacturing yield is also lowered.

Accordingly, an object of the present invention, in order to solve the above problems, the LED chip and the electrostatic discharge shock protection device formed on the lead frame to be connected in parallel by a wire, etc., the electrostatic discharge on the back of the lead frame formed LED chip An impact protection device is mounted to protect a light emitting diode from an electrostatic discharge shock, and to provide a high brightness light emitting diode with a built-in protection function for an electrostatic discharge shock while improving the brightness of the light emitting diode and simplifying the manufacturing process.

In addition, another object of the present invention is to provide a method of manufacturing a high brightness light emitting diode with a built-in protection against the electrostatic discharge shock.

In order to achieve the above object, the present invention provides a lead frame formed of a cathode lead and a cathode lead, a package formed so as to receive a portion of the lead frame, the entire upper and lower surfaces of the accommodated lead frame exposed; An LED chip mounted on an upper surface of an exposed lead frame, an electrostatic discharge shock protection device mounted on a lower surface of the exposed lead frame and connected in parallel with the LED chip through a wire, and filled into the LED chip It provides a high brightness light-emitting diode with a built-in protection function against the electrostatic discharge shock comprising a first molding material to protect the second molding material and the inside of the package to protect the electrostatic discharge shock protection device.

In addition, in the high-brightness LED having a built-in protection against electrostatic discharge shock, the electrostatic discharge shock protection device is preferably formed of a constant voltage diode or a semiconductor resistor, and more preferably, the constant voltage diode is a zener It is formed of any one diode selected from the group consisting of a diode, an avalanche diode, a switching diode and a Schottky diode.

In addition, in the high-brightness LED having a built-in protection against the electrostatic discharge shock of the present invention, the package is formed so as to accommodate a portion of the lead frame, the positive lead and the negative lead across the ends of each lead adjacent to each other It is preferable to have a fixing member which integrally fixes the positive electrode lead and the negative electrode lead.

In addition, in the high-brightness light emitting diode having a built-in protection against electrostatic discharge shock, the second molding material is preferably made of a white resin having excellent thermal conductivity.

In order to achieve the above object, another embodiment of the present invention, while receiving a portion of the lead frame consisting of the anode lead and the cathode lead to the inside, the step of forming a package by injection molding so that the entire upper and lower surfaces of the received lead frame is exposed And mounting an electrostatic discharge shock protection device on one surface of the exposed bottom surface of the exposed lead frame, and electrically connecting the bottom surface of the lead frame on which the electrostatic discharge shock protection device and the protection device are not mounted through a wire. And filling a second molding material in a package in which the electrostatic discharge impact protection device is mounted, mounting a LED chip on one surface of the exposed lead frame, and the LED chip and the electrostatic discharge. Electrically parallel connection of a shock protection device through a wire and a package in which the LED chip is mounted. It provides a method of manufacturing a high brightness light emitting diode with a built-in protection against electrostatic discharge shock comprising the step of filling the first molding material in the paper.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention.

In the drawings, the thickness of layers, films, panels, regions, etc., are exaggerated for clarity. Like reference numerals designate like parts throughout the specification.

Now, a high brightness light emitting diode with a built-in protection function against electrostatic discharge shock and a method of manufacturing the same according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

First, referring to FIGS. 3 and 4, a structure of a high-brightness LED having a built-in protection function against electrostatic discharge shock will be described in detail.

3 is a cross-sectional view illustrating a high brightness light emitting diode with a built-in protection against electrostatic discharge shock according to an embodiment of the present invention, and FIG. 4 is a high brightness light emitting device with built-in protection against electrostatic discharge shock shown in FIG. 3. A diagram schematically illustrating a reverse current prevention circuit of a diode.

3 and 4, the high-brightness LED having a built-in protection against electrostatic discharge shock according to an embodiment of the present invention, the lead frame 50 protruding from the package 10 formed of a synthetic resin material That is, it has a structure mounted on a printed circuit board (not shown) etc. via the positive electrode lead 51 and the negative electrode lead 52. FIG.

In particular, the package 10 according to the present invention accommodates a part of the positive lead 51 and the negative lead 52, that is, a part of the lead frame 50 inside, but has an upper surface of the received lead frame 50. All and part of the lower surface is formed to be exposed. In more detail, the exposed upper surface of the lead frame 50 is an area where the LED chip is to be mounted, and the lower surface of the exposed lead frame 50 is an area where the electrostatic discharge shock protection device is to be mounted.

In addition, the package 10 is a fixing member formed on the lower surface of the lead frame 50, that is, the anode lead 51 and the cathode lead 52 so that they span the ends of each lead 51, 52 adjacent to each other. Has (10a). This serves to integrally fix the positive electrode lead 51 and the negative electrode lead 52 to form a single package 10 for receiving the positive electrode lead 51 and the negative electrode lead 52, respectively.

The high-brightness LED having a built-in protection against electrostatic discharge shock is provided in the package 10 and includes a conventional LED chip 30 for irradiating light when power is applied, the LED chip 30 and It is made of an electrostatic discharge impact protection device 40 to prevent loss due to static electricity by being connected in parallel.

The LED chip 30 according to an embodiment of the present invention is mounted on the upper surface of the anode lead 51 among the upper surfaces of the lead frame 50 by a die bonding method by a conductive epoxy, and the electrostatic The discharge shock protection device 40 is mounted on the lower surface of the anode lead 51 of the lower surface of the lead frame 50 in the same manner as the LED chip 30.

In addition, the LED chip 30 is electrically connected to the positive lead 51 and the negative lead 52 through a wire 60, the electrostatic discharge shock protection device 40 is connected to the wire 60 Wire bonding is performed on the negative electrode lead 52.

Therefore, the LED chip 30 and the electrostatic discharge impact protection device 40 are connected in a parallel structure as shown in FIG.

At this time, the electrostatic discharge impact protection device 40 is formed of a constant voltage diode or a semiconductor resistor (varistor). In addition, the constant voltage diode is preferably made of any one diode selected from the group consisting of a zener diode, an avalanche diode, a switching diode, and a Schottky diode. In this embodiment, the zener diode is used as the constant voltage diode.

Meanwhile, in the present exemplary embodiment, the LED chip 30 and the electrostatic discharge impact protection device 40 are mounted on the same lead frame, that is, on the upper and lower surfaces of the anode lead 51, respectively, and are connected in parallel with each other. The LED chip 30 and the electrostatic discharge impact protection device 40 may be mounted on the upper and lower surfaces of the negative electrode lead 52 or the upper and lower surfaces of the different leads, respectively, and may be connected in parallel.

Here, reference numeral 20 which is not described here is a first molding material for protecting the LED chip 30, and reference numeral 70 is a second molding material for protecting the electrostatic discharge impact protection device 40. In this case, the first molding material 20 is made of a transparent resin containing a transparent material or a phosphor according to the color of the LED chip 30 to be implemented, and the second molding material 70 is thermally conductive It is preferable to consist of a high substance, for example, a white resin.

As described above, the high-brightness LED having a built-in protection against electrostatic discharge shock according to the present invention mounts the LED chip 30 on the upper surface of the anode lead 51 and the electrostatics on the lower surface of the anode lead 51. By mounting the discharge shock protection device 40 in parallel with each other, even if a reverse current is applied due to static electricity, the current is bypassed through the electrostatic discharge shock protection device 40 to generate an electrostatic discharge shock. To prevent damage.

In particular, the electrostatic discharge shock protection device 40 according to the present invention is the rear surface of the LED chip 30 that emits light, that is, the LED chip 30 on the basis of the lead frame 50, the electrostatic discharge shock protection device 40 Since the light emitting diode is mounted on the bottom surface, the light emitting diode acts as a barrier to block the light emitted from the lead frame 50d LED chip 30 positioned between them from being absorbed or scattered by the electrostatic discharge shock protection device 40. To increase the brightness.

In addition, since the second molding material 70 for protecting the electrostatic discharge impact protection device 40 is made of a white resin having excellent thermal conductivity, the LED chip 30 may be formed through the second molding material 70. By more effectively dissipating the generated heat, it is possible to obtain a heat dissipation effect superior to the light emitting diode according to the prior art.

Then, a method of manufacturing a high brightness LED having a built-in protection against electrostatic discharge shock according to the present embodiment will be described in detail with reference to FIGS. 5A to 5D and FIG. 3.

5A through 5D are cross-sectional views sequentially illustrating a method of manufacturing a high brightness LED having a built-in protection against electrostatic discharge shock according to an embodiment of the present invention.

First, as shown in FIG. 5A, a part of the lead frame 50 including the anode lead 51 and the cathode lead 52 is accommodated therein, but the entire upper surface of the accommodated lead frame 50 is exposed to the LED chip. While defining the mounting space 30a, a portion of the mounting space is exposed to form the injection molded package 10 such that the mounting space 40a of the electrostatic discharge impact protection device is defined.

The package 10 includes a fixing member 10a on the lower end of the lead frame 50, that is, the anode lead 51 and the cathode lead 52, which spans the ends of the leads 51 and 52 adjacent to each other. It is formed to have. The fixing member 10a integrally fixes the positive lead 51 and the negative lead 52 to serve as a single package 10 for receiving the positive lead 51 and the negative lead 52, respectively. do.

Next, as shown in FIG. 5B, the surface of the lead frame 50 in which the mounting space 40a of the electrostatic discharge impact protection device is defined, and in more detail, the lead frame in which the mounting space 30a of the LED chip is defined. When the surface of the 50 is referred to as the upper surface of the lead frame 50, the electrostatic discharge impact protection device 40 is mounted on the lower surface of the lead frame 50 by a die bonding method by conductive epoxy. In this embodiment, the electrostatic discharge shock protection device 40 is mounted on the bottom surface of the anode lead 51 among the bottom surfaces of the lead frame 50. Accordingly, the electrostatic discharge shock protection device 40 is the cathode lead. Electrically connected via 52 and the wire (60).

Then, as shown in FIG. 5C, the second molding member 70 is filled in the package 10 in which the electrostatic discharge impact protection device 40 is mounted. At this time, it is preferable to form the second molding material 70 using a white resin having excellent thermal conductivity in order to improve the heat radiation effect.

Next, as shown in FIG. 5D, the LED chip 30 is mounted on the upper surface of the lead frame 50 in which the mounting space 30a of the LED chip is defined. At this time, the LED chip 30 is mounted in the same manner as the electrostatic discharge impact protection device 40. In the present embodiment, the LED chip 30 is mounted on the upper surface of the anode lead 51 of the upper surface of the lead frame 50, which is connected to the electrostatic discharge impact protection device 40 in parallel with the anode lead ( 51) and the negative electrode lead 52 to be electrically connected by wire bonding.

Then, the first molding member 20 is filled in the package 10 in which the LED chip 30 is mounted (see FIG. 3). In this case, the first molding material 20 is preferably formed using a translucent resin containing a transparent material or a phosphor according to the color of the LED chip 30 to be implemented.

As described above, the manufacturing method of the high-brightness LED having a built-in protection against electrostatic discharge shock according to the present invention is formed so as to define the mounting space of the LED chip and the mounting space of the electrostatic discharge shock protection device at the time of forming the package. Then, by mounting the LED chip and the electrostatic discharge impact protection device in each mounting space, the manufacturing process is easier than the manufacturing method of the light emitting diode according to the prior art.

Therefore, the overall manufacturing process of the high-brightness LED having a built-in protection against electrostatic discharge shock can be reduced the process time, thereby improving the production yield.

Although the preferred embodiments of the present invention have been described in detail above, those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Accordingly, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concept of the present invention as defined in the following claims also fall within the scope of the present invention.

As described above, the present invention is formed so that the LED chip and the electrostatic discharge shock protection device is connected in parallel, but mounted up / down based on the lead frame, even if the reverse current is applied due to static electricity, the electrostatic discharge shock protection device The current is bypassed to prevent damage due to electrostatic discharge shock.

In addition, the present invention can improve the brightness of the light emitting diode by blocking the light emitted from the LED chip through the lead frame is absorbed or scattered by the electrostatic discharge shock protection device.

In addition, the present invention uses a material having excellent thermal conductivity as a molding material for protecting the electrostatic discharge impact protection device, it is possible to improve the heat dissipation effect of heat generated from the LED chip.

In addition, the present invention can reduce the process time of the overall manufacturing process of a high-brightness LED having a built-in protection against electrostatic discharge shock, thereby improving the production yield.

Claims (14)

A lead frame formed of a positive lead and a negative lead; A package accommodating a part of the lead frame therein, the package being formed such that the entire upper and lower surfaces of the accommodated lead frame are exposed; A fixing member which is formed such that the positive lead and the negative lead of the lead frame accommodated in the package span the ends of each lead adjacent to each other, thereby integrally fixing the positive lead and the negative lead; An LED chip mounted on the exposed lead frame; An electrostatic discharge shock protection device mounted on a lower surface of the exposed lead frame and connected in parallel with the LED chip through a wire; A first molding material filled in the package to protect the LED chip; And A second molding material filled in the package to protect the electrostatic discharge impact protection device; A high brightness light emitting diode with a built-in protection against electrostatic discharge shock. The method of claim 1, The LED chip is mounted on an upper surface of the anode lead of the lead frame, and the electrostatic discharge shock protection device is mounted on a lower surface of the cathode lead of the lead frame. diode. The method of claim 1, The LED chip is mounted on an upper surface of the cathode lead of the lead frame, and the electrostatic discharge shock protection device is mounted on a lower surface of the anode lead of the lead frame. . The method of claim 1, The LED chip is mounted on an upper surface of the anode lead of the lead frame, and the electrostatic discharge shock protection device is mounted on the lower surface of the anode lead of the lead frame. . The method of claim 1, The LED chip is mounted on an upper surface of the cathode lead of the lead frame, and the electrostatic discharge shock protection device is mounted on the lower surface of the cathode lead of the lead frame. . The method according to any one of claims 1 to 5, The electrostatic discharge shock protection device is a high brightness light emitting diode with a built-in protection against electrostatic discharge shock, characterized in that formed of a constant voltage diode or a semiconductor resistor. The method of claim 6, The constant voltage diode is a high brightness light-emitting diode with a built-in protection against electrostatic discharge shock, characterized in that formed of any one selected from the group consisting of a zener diode, an aberration diode, a switching diode and a Schottky diode. delete The method of claim 1, The second molding material is a high brightness light emitting diode with a built-in protection against electrostatic discharge shock, characterized in that made of a white resin. Accommodating a portion of the lead frame including the anode lead and the cathode lead to the inside, and injection molding the entire upper surface and the lower surface of the accommodated lead frame to be exposed to form a package; Mounting an electrostatic discharge impact protection device on one surface of the lower surface of the exposed lead frame; Electrically connecting the electrostatic discharge impact protection device with a lower surface of the lead frame on which the protection device is not mounted;  Filling a second molding material into a package in which the electrostatic discharge impact protection device is mounted; Mounting an LED chip on any one surface of an upper surface of the exposed lead frame; Electrically connecting the LED chip and the electrostatic discharge impact protection device through wires in parallel; And And filling a first molding material in a package in which the LED chip is mounted. A method of manufacturing a high brightness LED having a built-in protection against electrostatic discharge shock. The method of claim 10, The electrostatic discharge shock protection device, the method of manufacturing a high brightness light-emitting diode with a built-in protection against electrostatic discharge shock, characterized in that formed by a constant voltage diode or a semiconductor resistor. The method of claim 11, The constant voltage diode is a high brightness light emitting diode with a built-in protection against electrostatic discharge shock, characterized in that formed by any one diode selected from the group consisting of a zener diode, an avalanche diode, a switching diode and a Schottky diode. Way. The method of claim 10, The package is a manufacturing method of a high brightness light emitting diode with a built-in protection against electrostatic discharge shock, characterized in that it has a fixing member for integrally fixing the positive lead and the negative lead on the rear of the received lead frame. The method of claim 10, The second molding material is a manufacturing method of a high brightness light emitting diode with a built-in protection against electrostatic discharge shock, characterized in that formed using a white resin.

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