CN101207170A - LED lead frame and method for manufacturing LED using the lead frame - Google Patents

Abstract

The invention discloses an LED lead frame, which is a plate-type frame structure, characterized in that the plate-type frame is provided with protruding plates extending to the middle and spaced from each other in the peripheral frame, and the protruding plates respectively constitute a chip placement part, a The inner lead connection part, the outer electrode part, the tube body support part and the peripheral frame constitute the connection substrate, the inner lead connection part and the chip placement part are located at the front end of the outer electrode part, and the chip placement part is provided with a reflective cavity. The invention also discloses a method for manufacturing LEDs by using the lead frame. The LED chip is packaged by using the process of encapsulating colloid injection molding. After the external pin electrodes of the LED are stamped and bent, the LED is separated from the lead frame substrate into independent LED chips. device. The invention has the advantages of simple structure, convenient installation, good product consistency and the like.

Description

LED lead frame and method for manufacturing LED using the lead frame

technical field

The patent of the present invention relates to a light-emitting diode (LED) technology, in particular to a LED manufacturing technology, specifically a lead frame structure and a method for manufacturing an LED by using the lead frame.

Background technique

Figure 1 and Figure 2 show the known composition and structure diagrams of LEDs, respectively showing two types of LED manufacturing methods commonly used at present.

Figure 1 shows the PLCC type LED introduced in recent years. This structure belongs to the surface mount type, and has the advantages of high assembly precision, high density, and high production efficiency. Its main components include lead frame 101, LED chip 102, connecting lead 103, encapsulation compound 104, reflective cavity 105, and lens 106. Lead wires 103 , and finally place the encapsulant 104 and the lens 106 . This type of LED generally has a reflective cavity 105 to facilitate the packaging of the LED. The packaging colloid 104 is generally epoxy resin or silica gel, and there must be good airtightness between the packaging colloid 104 and the reflective cavity 105 to meet the requirements of product reliability. However, when used for a long time, especially for applications with harsh conditions such as outdoors, delamination of the encapsulating colloid 104 and the reflective cavity 105 often occurs, thereby affecting the quality of the product, and this type of product is greatly restricted.

Figure 2 shows the structure of the traditional bracket-type LED, which has the advantages of simple manufacturing process, but in the process of use, due to its own structural characteristics, it is often difficult to control the consistency of the final product, heat dissipation, assembly density, etc. And other characteristics are incomparable with SMD LED.

Contents of the invention

The purpose of the present invention is to provide an LED lead frame with simple structure, convenient installation and good product consistency.

Another object of the present invention is to provide a method for preparing an LED using the above-mentioned LED lead frame.

The LED lead frame structure of the present invention is a plate-type frame structure, which is characterized in that the plate-type frame is provided with convex plates extending to the middle and spaced from each other in the peripheral frame, and the convex plates respectively constitute a chip placement part, an inner lead connection part, The outer electrode part, the tube body support part and the peripheral frame constitute the connection substrate, which connects the components as a whole, the inner lead connection part and the chip placement part are located at the front end of the outer electrode part, and the chip placement part is provided with a reflection cavity.

As a further description of the above solution, the reflection cavity is in the shape of a cone or an ellipse cone. The number of chip placement parts is one or more, the number of corresponding external electrode parts is one or more; the color is one or more.

The lead frame is a unit and can be arrayed in N rows and M columns, where N≥1 and M≥1.

The method for manufacturing LEDs by using the above-mentioned LED lead frame of the present invention mainly includes:

a. Preforming of metal lead frame: processing metal sheet metal parts into a metal lead frame with a chip placement part, a reflection cavity, an inner lead connection part, an outer electrode part, a tube body support part, and a connecting substrate;

b. Chip placement: place the LED chip on the chip placement part on the metal lead frame, and complete the electrical connection;

c. Colloid injection molding: use packaging colloid injection molding process to package the LED chip, the external electrode part and the connecting substrate are arranged outside the packaging colloid, a part of the tube body support part is embedded in the packaging colloid, and the feeding port is set on the LED the bottom of the body;

d. Pin bending: disconnect the external electrode part from the position connected to the substrate and bend it. The pin bending can be bent to the bottom or side of the LED tube body;

e. Separation: punching disconnects the connection between the encapsulating gel and the support part of the tube body to form an independent LED.

The LED manufactured by the LED manufacturing method provided by the present invention has the following advantages:

1. Good product consistency: the plastic sealing molding process overcomes the large-scale fluctuation of the product's light emission characteristics caused by the insertion depth.

2. High product reliability: The integral molding process of packaging colloid overcomes the product reliability problem caused by the airtightness of the interface between the colloid and the reflection cavity.

3. It belongs to the surface mount type: it has the advantages of high assembly precision, high density and high production efficiency.

Description of drawings

Figure 1 Traditional bracket LED;

Figure 2 PLCC type LED;

Fig. 3 Preforming of metal lead frame;

Figure 4 chip placement and lead connection;

Figure 5 colloid injection molding;

Figure 6 pin bending;

Figure 7 is a schematic diagram of a discrete device;

Figure 8 Product array structure diagram.

Explanation of reference numerals: chip placement part 301, inner lead connection part 302, outer electrode part 303, tube body support part 304, connection substrate 305, reflective cup 306, gold wire 307, encapsulant 308, tube body support part and connection substrate Connection 309, connection 310 between the external electrode part and the connection substrate

Detailed ways

The concrete implementation examples of the present invention are described as follows:

Implementation example 1 provides a single-chip LED metal lead frame structure and a method for manufacturing LEDs using the lead frame:

As shown in Figure 3, the preformed schematic diagram of the metal lead frame, the sheet metal plate frame structure with a thickness of 0.3mm is processed into a convex plate extending to the middle and spaced from each other in the peripheral frame, and the peripheral frame constitutes a connecting substrate, said The convex plate respectively constitutes the metal lead frame of several components of the chip placement part 301, the inner lead connection part 302, the outer electrode part 303, the tube body support part 304, and the connection substrate 305; the connection substrate connects each component part into a whole, and the inner The lead connection part and the chip placement part are located at the front end of the external electrode part. The chip placement part is provided with a reflection cavity, and the chip placement part 301 is provided with a reflection cup 306, and the reflection cavity is in the shape of a cone or an ellipse cone. The number of chips placed is one or more, and the color is one or more.

As shown in the schematic diagram of chip placement in Figure 4, the LED chip 306 is placed in the reflective cup 306 of the chip placement part 301, and an ultrasonic welding process is used to complete the electrical connection between the chip electrode and the external electrode 303 on the metal lead frame using a gold wire 307 .

As shown in the schematic diagram of packaging in Figure 5, the LED chip 306 is packaged with the encapsulation compound 308 by injection molding, the external electrode part 302 and the metal lead frame 304 are arranged outside the encapsulation compound 308, and a part of the tube support part 303 is embedded in the encapsulation compound 308. Inside the encapsulant 308 ; the feed port for glue injection is set at the bottom of the LED.

As shown in FIG. 6 , the schematic diagram of pin bending: the external electrode part 302 is disconnected from the position 309 connected with the metal lead frame 304 and bent into shape.

Separation schematic diagram as shown in FIG. 7 : the connection of the encapsulant 308 and the support part 303 of the tube is broken by punching to form an independent LED.

Implementation example 2 provides a solution for mass production of lead frames, which is an array structure of 4*10. The schematic diagram is shown in Figure 8.

Claims (9)

1. LED lead frame, this lead frame is board-like frame structure, it is characterized in that, board-like framework is by the flange that is provided with in the peripheral frame to centre extension and space, described flange constitutes chip mount portion, lead connecting portion, external electrode portion, body support portion respectively, and peripheral frame constitutes the connection substrate, connects substrate and connects each part as a whole, lead connecting portion and chip mount portion are positioned at the front end of external electrode portion, and chip mount portion is provided with reflection cavity.

2. as right 1 described LED lead frame, it is characterized in that described reflection cavity is circular cone or elliptic cone shape.

3. as right 1 described LED lead frame, it is characterized in that described chip mount portion quantity is one or more.

4. as right 3 described LED lead frames, it is characterized in that the quantity of described external electrode portion is one or more accordingly.

5. as right 1 described LED lead frame, it is characterized in that described lead frame is a unit, can array be the capable M row of N, N 〉=1 wherein, M 〉=1.

6. a method that adopts each described LED lead frame of claim 1 to 5 to make LED is characterized in that it comprises the steps:

A. the preforming of metal lead wire frame: the metal sheet metal component is processed into has chip mount portion, reflection cavity, lead connecting portion, external electrode portion, body support portion, connect the metal lead wire frame of substrate;

B. chip mount: led chip is placed in chip mount portion on the die-attach area, and finishes and be electrically connected;

C. colloid injection mo(u)lding: adopt the technology of packing colloid injection mo(u)lding, led chip is encapsulated, external electrode portion, connection substrate are arranged at the packing colloid outside, and the part of body support portion is embedded in packing colloid inside;

D. pin bending: outer electrode portion is disconnected and bending from the position that links to each other with substrate;

E. separate: punching press disconnection packing colloid is connected with the body support portion, forms independently LED.

7. as right 6 described LED manufacture methods, it is characterized in that packing colloid injection molding process described in the described c step, charging aperture are arranged at the bottom of LED body.

8. as right 6 described LED manufacture methods, it is characterized in that the pin bending is to be folded to the bottom surface of LED body or side in the described d step.

9. as right 6 described LED manufacture methods, it is characterized in that reflection cavity is directly to be stamped to form in the described a step on the LED lead frame.

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