WO2008104103A1

WO2008104103A1 - Method for manufacturing a plurality of smd leds and structure thereof

Info

Publication number: WO2008104103A1
Application number: PCT/CN2007/000643
Authority: WO
Inventors: Tsungwen Chan; Chinhsiang Ku
Original assignee: Tsungwen Chan; Chinhsiang Ku
Priority date: 2007-03-01
Filing date: 2007-03-01
Publication date: 2008-09-04

Abstract

A method for manufacturing a plurality of SMD LEDs and the structure thereof, the structure (10) comprising a plurality of light emitting units (100). Each light emitting unit (100) comprises a light emitting chip (1), a heat dissipation device (2) and two electrodes (31,32), and the light emitting units (100) are connected by a support structure (5). The manufacturing method includes cutting a basic shape on a metal strip (6), forming the support structure (5) using a moulding process, then fixing the light emitting chips (1) to the metal strip (6) having the basic shape and connecting two electrodes (31,32), connecting the adjacent light emitting units (100) in series or in parallel, and cutting the excess regions and performing packaging.

Description

Multi-layer surface-adhesive light-emitting diode manufacturing method and structure thereof

The invention relates to a method for manufacturing a plurality of surface-adhesive light-emitting diodes and a structure thereof, in particular to a surface-adhesive light-emitting diode, which can effectively provide a heat dissipation mechanism of the light-emitting diode, reduce energy loss, and has a simple and environmentally friendly manufacturing process. LED production technology.

Background technique

Among various types of optoelectronic components, LEDs (Light Emi tt ing Diodes) have a long history and wide application fields due to their small size, long life, fast response, power saving, shock resistance, low cost, and suitable for mass production. It is the component with the largest field value in all kinds of photoelectric components.

The light-emitting diode is a light-emitting element made of a semiconductor material, and has two electrode terminals, a voltage is applied between the terminals, a very small current is supplied, and the remaining energy is in the form of light via the combination of electrons and holes. Excitation release, this is the basic principle of light-emitting diodes. Unlike ordinary incandescent bulbs, LEDs are cold-emitting, have low power consumption, long component life, no need for warm-up time, fast response, etc., plus their small size, vibration resistance, mass production, easy to match The application requirements are made into very small or arrayed components. Therefore, LEDs have been widely used in indicators and display devices for information, communication and consumer electronics, and have become an indispensable element in daily life. According to different applications of various products, the die can be packaged into different light-emitting diodes. Currently, the packaged product types include bullet type, cluster type, digital display, dot matrix type and surface adhesion type (SMD). Among them, the surface-adhesive LED is smaller than other conventional LEDs, so it is mainly used in the screen backlight of mobile phones and the buttons of mobile phones, which is in great demand in the current market.

1

Confirmation The aforementioned light-emitting diodes have much lower heat loss than ordinary incandescent light bulbs, so the heat generation problem is not considered in general applications. However, in view of the increasingly mature high-brightness light-emitting diode products, the heat is greatly increased. If it is an array of light-emitting diodes, the heat generation cannot be ignored. For this reason, the design of current LEDs has gradually paid attention to the addition of heat dissipation structures in the process.

The heat dissipation structure of the conventional surface-adhesive light-emitting diode is as shown in FIG. 4 of US Pat. No. 7,138,660. The light-emitting diode of the light-emitting diode is placed on the positive terminal, and the light-emitting die is respectively wired to positive and negative. At both ends of the electrode, the completed LED does not require additional optical components or reflectors, and the path of the light after soldering can be parallel to each board. The surface-bonded LED emits heat through a positive metal.

In the foregoing prior art structures or other light emitting diode devices, the heat dissipation mechanism has the following disadvantages and needs to be improved:

1. The heat dissipation mechanism of existing LEDs is not enough to cope with the heat generated by them. When the temperature rises, it will not only cause the brightness to drop, but also exceed 85 degrees Celsius to accelerate the deterioration of the components.

2. Phosphors used in LED packaging, when the temperature is too high, they will absorb water after shutdown. These water molecules will blacken the phosphor, which will reduce the luminous efficiency and affect the product efficiency.

3. Existing LEDs will conduct heat to the copper foil on the printed circuit board for heat dissipation, but the heat dissipation mechanism based on the heat conduction of the two electrodes is inefficient, which is not enough to effectively conduct the heat generated by the LED.

4. Existing LEDs are soldered in the series/parallel packaging process of multiple illuminating dies, resulting in a large number of solder joints, which are not in compliance with the European Union's Electronic Motor Equipment Hazardous Substances Directive (RoHs), RoHs The main objective of the Directive is to limit the harmful substances in electrical and electronic equipment to protect human health and the environment. Summary of the invention

A first object of the present invention is to provide a method for fabricating a plurality of surface-adhesive light-emitting diodes and a structure thereof, which achieve sufficient heat dissipation by an added heat dissipation structure, and the added structure can be combined with an existing process There is no need to increase the cost significantly, but it can effectively increase the service life and luminous efficiency of the product.

A second object of the present invention is to provide a method for fabricating a plurality of surface-adhesive light-emitting diodes and a structure thereof, and the heat-dissipating structure can also be combined with a heat-dissipating mechanism of the printed circuit board to more effectively conduct heat generated by the light-emitting diodes.

A third object of the present invention is to provide a method for fabricating a plurality of surface-adhesive light-emitting diodes and a structure thereof, which have no soldering operation in a series/parallel manufacturing process of a plurality of light-emitting dies, and are in compliance with the European electronic motor equipment. Hazardous Substances Directive (RoHs).

A fourth object of the present invention is to provide a method for fabricating a plurality of surface-adhesive light-emitting diodes and a structure thereof. After the plurality of light-emitting diodes are serially/parallel-connected, a single point light source can be assembled into a whole light-emitting surface. Form a wider use.

A plurality of surface-adhesive light-emitting diode structures having the above-mentioned objectives, comprising more than one light-emitting unit, each light-emitting unit comprising a light-emitting die and a heat-dissipating structure in contact therewith, wherein the light-emitting die is provided with two electrodes, the light emitting The two wires of the die extension are respectively connected to the two electrodes, and the heat dissipation structure and the two electrodes are formed on the same metal strip; and the invention is arranged between the two adjacent light emitting units by the wire or the metal strip body / Parallel, and each of the light-emitting units is fixed by a support structure, so that the heat-dissipating structures and the electrodes are held in a fixed position to facilitate packaging.

Thereby, the manufacturing method of the foregoing structure firstly cuts the heat dissipating structure and the excess area other than the two electrodes on the metal strip, so that the metal strip has a basic shape; and then the plastic injection molding is used. a structure in which a support structure is ejected on a metal strip so that the support structure can fix a plurality of heat dissipating structures and electrodes in a unit range; then, the solid metal is fixed and lined on the metal strip that has been cut out, and Serial/parallel connection between adjacent light-emitting units; finally cutting off other cutting regions such as the heat-dissipating structure on the metal strip and the connection between the two electrodes, and then packaging, and then completing the multiple surface-adhesive LED structures Cut from the metal strip.

In addition, a plurality of surface-adhesive light-emitting diodes of each group can also be arranged in series/parallel, in such a manner that the connection region is also directly cut on the same metal strip, and two adjacent surfaces are turned on by the connection region. Adhesive LEDs to provide more product options.

The multi-surface adhesion type light-emitting diode of the invention and the structure thereof can effectively increase the service life and the luminous efficiency of the product without greatly increasing the cost, and the welding process is eliminated when performing the serial/parallel operation of the plurality of illuminating dies , meets environmental protection needs, and can greatly increase production efficiency. DRAWINGS

1 is a flow chart of a method for manufacturing a plurality of surface-adhesive light-emitting diodes according to Embodiment 1 of the present invention; FIG. 2 is a schematic view showing a structure of a metal strip for cutting an excess portion in the first step of Embodiment 1 of the present invention; Schematic diagram of the support structure setting of the second step in Embodiment 1;

4 is a schematic view showing a structure of a solid crystal and a wire bonding in a third step in Embodiment 1 of the present invention;

5 is a schematic structural view of a metal strip after cutting in a fourth step in the first embodiment of the present invention; FIG. 6 is a schematic view showing the encapsulation of the fifth step in the first embodiment of the present invention;

Figure 7 is a flow chart showing a manufacturing method of Embodiment 2 of the present invention;

8 is a schematic structural view of a metal strip after cutting in a fourth step in the first embodiment of the present invention; FIG. 9 is a schematic view showing the encapsulation of the fifth step in the second embodiment of the present invention; 10 is a schematic diagram of an actual circuit according to Embodiment 2 of the present invention;

11 is a schematic diagram of an equivalent circuit of Embodiment 2 of the present invention;

Wherein: F10, step 1; Fl l, step 2; Fl step 3; F, step 4; F14, step 5; F15, step 4; F16, step 5; Light-emitting diode; 100, light-emitting unit; 1, light-emitting die; 2, heat-dissipating structure; 31, electrode; 32, electrode; 41, wire; 42, wire; 43, wire; 5, support structure; 61, multi-turn area; 62, cutting area; 63, cutting line; 64, connecting area. detailed description

Example 1

Please refer to FIG. 1 to FIG. 6 , which are schematic diagrams showing a structure and a related structure of a plurality of surface mount type light emitting diodes 10 according to the present invention; the plurality of surface mount type light emitting diodes 10 are composed of more than one light emitting unit 100 in parallel. The embodiment is illustrated in three parts. Each of the light-emitting units 100 includes a light-emitting die 1 disposed on a heat-dissipating structure 2. The heat-dissipating structure 2 is provided with two electrodes 31 and 32, and emits light. The die 1 extends from the two wires 41, 42 respectively connected to the two electrodes 31, 32. The heat dissipation structure 2 and the two electrodes 31, 32 are formed on the same metal strip 6; between two adjacent light-emitting units, The opposite electrodes 31 are connected in parallel by the wires 43, and the other electrode 32 is connected to the metal strip 6 in parallel; and between the heat dissipation structure 2 and the electrodes 31 and 32 covered by each of the plurality of surface-adhesive LEDs 10 , a support structure 5 is provided for fixing, and then packaged by a general light-emitting diode arrangement to form a plurality of surface-adhesive light-emitting diodes that can be used.

10.

According to the foregoing structure, the plurality of surface-adhesive light-emitting diodes 10 are the two electrodes when in use. 31, 32 contact with a printed circuit board for surface adhesion, and then electrically conductive to cause the light-emitting die 1 to start to emit light, the heat generated by the light-emitting die 1 is extended by the heat-dissipating structure 2 to other positions, if necessary, The printed circuit board has external heat dissipation measures to conduct excess heat to the outside of the printed circuit board. Since the heat dissipation structure 2 itself is not in contact with any of the electrodes, it is in a non-polar state and does not interfere with the use of other circuits during use.

In addition, the heat dissipation structure 2 can be bent into various shapes as needed to facilitate contact with other heat dissipation devices, or change the heat dissipation space configuration to provide the most efficient heat dissipation result; or the heat dissipation structure 2 can change its area according to needs, The increased heat dissipation area can produce better heat dissipation results.

The detailed method for manufacturing the plurality of surface-adhesive LEDs 10 is as follows: First step P10, as shown in FIG. 2, first, the heat-dissipating structure 2 is removed from the metal strip 6 by a die. The excess area 61 other than the two electrodes 31, 32 forms the basic shape of the electrodes 31, 32 and the heat dissipation structure 2 on the metal strip 6;

In the second step F11, as shown in FIG. 3, the support structure 5 is emitted in a range covered by the plurality of surface-adhesive light-emitting diodes 10 by using a plastic injection molding method, so that the support structure 5 can fix the plurality of heat dissipation structures 2 and the electrodes 31, 32;

Step 3: F12, as shown in FIG. 4, performing solid crystal bonding and wire bonding on the metal strip 6 with the cut shape, first placing the light emitting die 1 on the heat dissipation structure 2, and then connecting the two wires 41, 42 is connected to the two electrodes 31, 32 by the light-emitting crystal grains 1, and the electrodes 31 are connected in parallel by a wire 43 between the two adjacent light-emitting units 100;

In the fourth step F13, as shown in FIG. 5, using another die, the other cutting regions 62 of the heat dissipation structure 2 and the two electrodes 31, 32 on the metal strip 6 are cut off, so that the light-emitting units 100 are The heat dissipation structure 2 forms an independent individual with the electrodes 31, 32, but still can be designed due to the design of the support structure 5. Keep positioning;

In the fifth step F14, as shown in FIG. 6, finally, the LED structure is packaged, the structure of the plurality of surface-adhesive LEDs 10 is completed, and then the metal strip 6 is cut off at the cutting line 63 according to the required size. That is, the present invention has been completed.

Example 2:

Please refer to FIG. 7 to FIG. 11 , which is a schematic diagram of a method for fabricating a plurality of surface-adhesive LEDs 10 and related structures. This embodiment further generates a series/parallel LED structure, and steps 1 to 3 are performed. Embodiment 1 is the same, and the technical features of the two are as follows:

In the fourth step F15, as shown in FIG. 8, another cutting mode is used to cut off the connection portion 62 of the heat dissipation structure 2 and the two electrodes 31, 32 on the metal strip 6, and two adjacent ones are Between the surface-adhesive LEDs 10, the metal strip 6 retains a connection region 64, which is connected to the electrodes 31 and 32 of the light-emitting unit 100 of the two adjacent surface-adhesive LEDs 10, respectively. Forming a series/parallel structure as shown in FIG. 10 and FIG. 11 , and the heat dissipation structure 2 and the electrodes 31 , 32 of each of the light emitting units can be kept positioned by the support structure 5 ;

In the fifth step F16, as shown in FIG. 9, finally, the LED structure is packaged to form a plurality of surface-adhesive LEDs 10, and a plurality of light-emitting units 100 are connected in parallel in each of the plurality of surface-adhesive LEDs 10, and Two adjacent surface-mounting LEDs 10 are connected in series.

According to the above description, the present invention eliminates the welding process when performing the serial/parallel operation of the plurality of light-emitting dies 1, and meets environmental protection requirements, and can greatly increase the production efficiency.

The detailed description of the present invention is not intended to limit the scope of the present invention, and the equivalents and modifications of the present invention should be included in the present invention. In the scope of the patent.

Claims

Patent claim

A method for manufacturing a plurality of surface-adhesive light-emitting diodes, wherein: the steps are as follows: Step 1: using a die to cut off a metal strip to form a heat dissipation structure and an excess area other than the two electrodes, Forming a basic shape of the electrode and the heat dissipation structure on the metal strip; Step 2: providing a support structure on the metal strip, so that the support structure can fix a plurality of heat dissipation structures and electrodes associated therewith;

Step 3: performing solid crystal bonding and wire bonding on the metal strip that has been cut out, and causing the light-emitting dies in the same plurality of surface-adhesive LEDs to be serially/parallel;

Step 4: cutting off the heat dissipating structure on the metal strip and other cutting areas such as the joints with the opposite electrodes, and using the supporting structure to maintain the positioning;

Step 5: Package the LED, and then cut off the completed surface-mount LED structure from the metal strip.

2. The method according to claim 1, wherein the support structure is provided by injection molding.

3. The method of manufacturing a plurality of surface-adhesive light-emitting diodes according to claim 1, wherein: the series/parallel connection between the light-emitting dies is cut and formed on the metal strip.

4. The method of manufacturing a plurality of surface-adhesive light-emitting diodes according to claim 1, wherein: the series/parallel connection between the light-emitting dies is formed by wire bonding.

5. A method for manufacturing a plurality of surface-adhesive light-emitting diodes, wherein: the steps are as follows: Step 1: using a die to cut off a metal strip to form a heat dissipation structure and excess regions other than the two electrodes, Forming a basic shape of the electrode and the heat dissipation structure on the metal strip; Step 2: providing a support structure on the metal strip, so that the support structure can fix a plurality of heat dissipation structures and electrodes associated therewith;

Step 4: cutting out other cutting regions such as the heat dissipating structure and the connection portion of the electrode with the related surface of the metal strip, and between the two adjacent surface-adhesive LEDs, the metal strip remains connected Zone, and still maintain positioning due to the support structure;

Step 5: Perform a light-emitting diode package, and then cut off a plurality of surface-adhesive LED structures from the metal strip.

A method of manufacturing a plurality of surface-adhesive light-emitting diodes according to claim 5, wherein the support structure is provided by injection molding.

The method for manufacturing a plurality of surface-adhesive light-emitting diodes according to claim 5, wherein the series/parallel connection between the light-emitting dies is cut and formed on the metal strip.

A method of manufacturing a plurality of surface-adhesive light-emitting diodes according to claim 5, wherein the series/parallel connection between the light-emitting dies is formed by wire bonding.

A multi-surface adhesion type light emitting diode structure, characterized in that:

More than one equivalent light-emitting unit, each of the light-emitting units is connected in a series/parallel manner, each light-emitting unit has a light-emitting die, a heat-dissipating structure and two electrodes, and the light-emitting die is used as a light source, and is fixed at In the heat dissipation structure, the two wires are distributed beside the light-emitting die, and the light-emitting die extends from the two electrodes;

A heat dissipating structure is fixed on each of the light emitting units, so that the heat dissipating structure and the electrodes of each of the light emitting units can be maintained at a fixed position.

10. The multiple surface mount LED structure of claim 9, wherein: the heat dissipation structure can be combined with other heat sinks to provide a more efficient heat dissipation result.

11. The multi-surface adhesion type light emitting diode structure according to claim 9, wherein: the heat dissipation structure is bent into various shapes as needed to obtain the highest efficiency heat dissipation result. 12. The multi-surface adhesion type light emitting diode structure according to claim 9, wherein: the heat dissipation structure can change its area size as needed to obtain the highest efficiency heat dissipation result.

13. The multi-surface adhesion type LED structure according to claim 9, wherein the heat dissipation structure and the two electrodes are simultaneously completed by the same tape.

14. The multi-surface-adhesive LED structure of claim 9, wherein: one or more of the plurality of surface-adhesive LED structures have a connection region therebetween, and the connection region is Serial/parallel connection.

15. The multi-surface adhesion type LED structure according to claim 14, wherein the connection region is completed in synchronization with the heat dissipation structure and the electrode in the same tape.