CN115954430A - Manufacturing method of small-size LED lamp bead - Google Patents

Abstract

The invention discloses a method for manufacturing a small-size LED lamp bead, which comprises a metal substrate processing step, a lamp base preparing step, an injection molding step, a die bonding and wire bonding step, a glue pouring step and a cutting step. The invention respectively grows the convex public lamp feet, the first branch lamp feet, the second branch lamp feet and the third branch lamp feet on the back of the public electrode, the first branch electrode, the second branch electrode and the third branch electrode of the lamp bead bracket directly, and only cuts the bracket substrate when cutting, thereby effectively avoiding the water vapor invasion channel generated by the small-size LED lamp bead and ensuring that the air tightness of the small-size LED lamp bead is good.

Description

A kind of manufacturing method of small size LED lamp bead

technical field

The invention relates to the field of LEDs, in particular to a method for manufacturing small-sized LED lamp beads.

Background technique

With the maturity of LED technology, the pixels of LED displays are getting higher and higher, and the pixels are becoming more and more dense. This requires that the size of the LED lamp beads that make up the pixels must be very small, which also poses a challenge to the packaging technology of LEDs. Higher requirements; and the current small-sized LED lamp beads mainly have two packaging types, TOP and CHIP.

When the existing TOP small-sized lamp beads are manufactured, the metal bracket punched by sheet metal is first wrapped with plastic material to form a lamp cup with a bowl-cup structure, and then the light-emitting chip is fixed in the lamp cup and the corresponding wire welding is performed. , and then inject epoxy resin into the lamp cup to form a protective layer for protection. Finally, the lamp pin of the metal bracket needs to be bent to the bottom of the lamp cup; , The protective layer and the metal bracket are slightly cracked and peeled off, thereby forming a water vapor intrusion channel, which seriously affects the airtightness of the TOP small-sized lamp bead.

However, the existing CHIP-type small-size lamp beads are directly bonded to the BT (Bismaleimide Triazine) board with batches of light-emitting chips by molding, and then injected with a protective body to protect the light-emitting chips, and then cut into individual pieces. lamp beads; while the ink covered on the surface of the BT board leads to poor bonding with the protection body, making it easy to form a water vapor intrusion channel between the BT board and the protection body; in addition, when cutting into individual lamp beads in the later stage, cutting The protective body of the final lamp bead is likely to have fine and dense cracks, and the cracks also form water vapor intrusion channels; therefore, the existing CHIP type small-sized lamp beads also have airtightness problems.

In view of the above problems, it is necessary to study a method for manufacturing small-sized LED lamp beads, and the manufactured small-sized LED lamp beads have the advantage of good airtightness.

Contents of the invention

The object of the present invention is to provide a method for manufacturing a small-sized LED lamp bead, and the small-sized LED lamp bead manufactured by the method has the advantage of good airtightness.

In order to achieve the above object, the solution of the present invention is:

A method for manufacturing a small-sized LED lamp bead, comprising:

Metal substrate processing step: manufacture several metal supports and the substrate main body connected with each metal support on the metal substrate, each metal support includes separated common electrodes, first branch electrodes, second branch electrodes and third branch electrodes, each The common electrode, the first branch electrode, the second branch electrode and the third branch electrode of each metal support are respectively connected to the substrate main body;

The step of preparing the lamp pins: the metal substrate is prepared for the lamp pins, so that the backs of the common electrodes, the first branch electrodes, the second branch electrodes and the third branch electrodes of each metal bracket grow protruding common lamp pins, the second branch electrodes, etc. One branch lamp foot, the second branch lamp foot and the third branch lamp foot to obtain a support substrate with a plurality of lamp bead supports; the lamp bead support includes metal supports and common electrodes and first branch electrodes grown on the metal supports respectively , the common lamp pins on the back of the second branch electrode and the third branch electrode, the first branch lamp pin, the second branch lamp pin and the third branch lamp pin;

Injection molding step: place the bracket substrate in the mold cavity and inject and grow multiple independent plastic bodies on the bracket substrate, so that each lamp bead bracket is combined with an independent plastic body to form a lamp bead base; lamp bead bracket The common electrode, the first branch electrode, the second branch electrode, the third branch electrode, the common lamp pin, the first branch lamp pin, the second branch lamp pin and the third branch lamp pin are at least partially exposed outside the plastic body, and the lamp The connections between the common electrode, the first branch electrode, the second branch electrode and the third branch electrode of the bead holder and the main body of the substrate are exposed outside the plastic body;

Die-bonding and wire-bonding steps: Carry out crystal-bonding and wire-bonding operations on each lamp bead base, so that the front of the common electrode of each lamp bead base is fixed with three light-emitting chips for emitting red light, green light and blue light respectively. The three light-emitting chips are respectively connected to the front of the first branch electrode, the second branch electrode and the third branch electrode of the lamp bead base through metal wires, and the two light-emitting chips for emitting green light and blue light are also connected through metal wires respectively. Connect to the front side of the common electrode;

Glue filling step: Potting epoxy glue on the front of each lamp bead base. After the epoxy glue is cured, a light-transmitting protective body is formed. The protective body covers the three light-emitting chips matched on each lamp bead base and each lamp. The front of the metal stand for the bead base;

Cutting step: cutting the bracket substrate so that the common electrode, the first branch electrode, the second branch electrode and the third branch electrode of each lamp bead base are disconnected from the main body of the substrate, so as to obtain independent small-sized LED lamp beads .

In the metal substrate processing step, a plurality of through holes are formed on the metal substrate by performing etching treatment, laser cutting treatment or punching treatment on the metal substrate, and then a plurality of metal brackets are manufactured on the metal substrate and connected with each metal bracket main body of the substrate.

In the step of preparing the lamp pins, the method of preparing the lamp pins on the metal substrate is as follows:

Step 1: Coating ink on the entire surface of the metal substrate;

Step 2: Curing and cleaning the ink coated on the surface of the metal substrate, wherein the ink coated on the back of each common electrode needs to grow the common lamp pin, and the first branch needs to be grown on the back of each first branch electrode The ink coated on the area of the lamp pin, the ink coated on the area where the second branch lamp pin needs to be grown on the back of each second branch electrode, and the ink that needs to grow the third branch lamp pin on the back of each third branch electrode The ink coated on the area is washed off, and the remaining ink coated on the surface of the metal substrate is cured;

Step 3: Electroplating the metal substrate, so that the area where the common lamp pin needs to be grown on the back of each common electrode grows the common lamp pin by electroplating, and the area where the first branch lamp pin needs to be grown on the back of each first branch electrode grows the first Branch lamp pins, the area where the second branch lamp pins need to be grown on the back of each second branch electrode is electroplated to grow the second branch lamp pins, and the area where the second branch lamp pins need to be grown on the back of each second branch electrode is electroplated to grow the second branch lamp pins Branch light foot;

Step 4: Wash off all the ink coated on the surface of the metal substrate.

The common lamp pin, the first branch lamp pin, the second branch lamp pin and the third branch lamp pin are all made of copper.

There is also a protective layer preparation step between the lamp pin preparation step and the injection molding step; the protective layer preparation step is: electroplating a conductive protective layer on the surface of the bracket substrate by means of electroplating.

In the injection molding step, the plastic body is a plastic lamp cup, and the plastic lamp cup has a common electrode that separates the metal bracket, a lamp cup dam that separates the first branch electrode, the second branch electrode and the third branch electrode, and has The lamp cup wall surrounding the metal bracket; in the glue filling step, the protective body is filled in the inner cavity of the lamp cup wall.

The lamp cup dam protrudes from the front of the metal bracket.

In the injection molding step, the plastic body is a plastic base, and the plastic base has a base dam separating the common electrode, the first branch electrode, the second branch electrode and the third branch electrode of the metal bracket.

The base dam protrudes from the front of the metal support.

The metal substrate is made of copper.

After adopting the above scheme, the present invention directly grows protruding public lamp pins, first branch lamp pins, and second branch electrodes directly on the back of the common electrode, first branch electrode, second branch electrode and third branch electrode The second branch lamp pin and the third branch lamp pin, so that there is no need to bend the lamp bead bracket, so as to avoid the water vapor intrusion channel formed between the lamp bead bracket and the plastic body and the protection body due to bending the lamp bead bracket; Moreover, the present invention sets each plastic body independently during injection molding, so that the present invention only needs to cut the support substrate when cutting and does not need to cut the plastic body and the protective body, thereby avoiding the plastic body and the protective body due to cutting. And produce water vapor intrusion channel; As can be seen from the foregoing, a small-size LED lamp bead is produced by a small-size LED lamp bead manufacturing method of the present invention, which can effectively avoid the water vapor intrusion channel of the small-size LED lamp bead, so that the small-size LED lamp bead The airtightness of the beads is good.

Description of drawings

1 is a schematic diagram of a manufacturing method of Embodiment 1 of the present invention;

Fig. 2 is an enlarged view of place a of Fig. 1;

Fig. 3 is the enlarged view of place b of Fig. 1;

Figure 4 is an enlarged view of c in Figure 1;

Figure 5 is an enlarged view at d of Figure 1;

Figure 6 is an enlarged view at e of Figure 3;

Fig. 7 is an exploded view of the structure of a small-sized LED lamp bead according to Embodiment 1 of the present invention;

Fig. 8 is a schematic structural diagram of a small-sized LED lamp bead according to Embodiment 1 of the present invention;

Fig. 9 is a schematic diagram of the manufacturing method of Embodiment 2 of the present invention;

Figure 10 is an enlarged view at f of Figure 9;

Figure 11 is an enlarged view of the g place in Figure 9;

Figure 12 is an enlarged view at h of Figure 9;

Fig. 13 is an exploded view of the structure of a small-sized LED lamp bead according to Embodiment 2 of the present invention;

Fig. 14 is a schematic structural diagram of a small-sized LED lamp bead according to Embodiment 2 of the present invention;

Label description:

Bracket substrate A, lamp bead bracket A1,

Metal substrate 1, substrate main body 10,

Metal support 11, common electrode 111, first branch electrode 112, second branch electrode 113, third branch electrode 114,

through hole 12,

Common light pin 2, first branch light pin 3, second branch light pin 4, third branch light pin 5,

plastic body B,

Plastic lamp cup B1, lamp cup dam B11, lamp cup wall B12,

Plastic base B2, base dam B21,

Lamp bead base C,

Light-emitting chip D,

metal wire E,

Protector F,

Small size LED lamp bead Z.

Implementation

In order to further explain the technical solution of the present invention, the present invention will be described in detail below through specific examples.

As shown in Figures 1 to 14, the present invention discloses a method for manufacturing small-sized LED lamp beads, which includes:

Metal substrate processing step: manufacture several metal supports 11 on the metal substrate 1 and the substrate main body 10 connected to each metal support 11, each metal support 11 includes a separated common electrode 111, a first branch electrode 112, and a second branch electrode 113 and the third branch electrode 114, the common electrode 111, the first branch electrode 112, the second branch electrode 113 and the third branch electrode 114 of each metal support 11 are respectively connected with the substrate main body 10, and the metal substrate 1 can be strong and conductive Excellent copper material;

The step of preparing lamp pins: performing lamp pin preparation on the metal substrate 1, so that the backs of the common electrode 111, the first branch electrode 112, the second branch electrode 113 and the third branch electrode 114 of each metal bracket 11 grow protrusions respectively. The public lamp pin 2, the first branch lamp pin 3, the second branch lamp pin 4 and the third branch lamp pin 5 to obtain a bracket substrate A with a plurality of lamp bead brackets A1; the lamp bead bracket A1 includes a metal bracket 11 And the common lamp pin 2, the first branch lamp pin 3, and the second branch lamp pin 4 grown on the back of the common electrode 111, the first branch electrode 112, the second branch electrode 113 and the third branch electrode 114 of the metal support 11 respectively and the third branch lamp pin 5;

Injection molding step: place the bracket substrate A in the mold cavity and inject and grow multiple independent plastic bodies B on the bracket substrate A, so that each lamp bead bracket A1 is combined with an independent plastic body B to form a lamp bead base Seat C; the common electrode 111, the first branch electrode 112, the second branch electrode 113, the third branch electrode 114, the common lamp pin 2, the first branch lamp pin 3, the second branch lamp pin 4 and the first branch lamp pin 4 of the lamp bead bracket A The three branch lamp pins 5 are at least partly exposed outside the plastic body B, and the joints of the common electrode 111, the first branch electrode 112, the second branch electrode 113 and the third branch electrode 114 of the lamp bead bracket A and the substrate main body 10 are exposed outside the plastic body B;

Die-bonding and wire-bonding step: Carry out crystal-bonding and wire-bonding operations on each lamp bead base C, so that the front of the common electrode 111 of each lamp bead base C is fixed with three electrodes for emitting red light, green light and blue light respectively. Light-emitting chip D, wherein the red light-emitting chip used for emission is fixed by silver glue, the two light-emitting chips used for emission of blue and green are fixed by insulating glue, and the three light-emitting chips D are connected to the lamp bead base by metal wire E respectively. The front of the first branch electrode 112, the second branch electrode 113 and the third branch electrode 114 of the seat C are connected, and the two light-emitting chips D for emitting green light and blue light are also respectively connected to the front of the common electrode 111 through the metal wire E It should be noted that due to the particularity of the red light-emitting chip, the red light-emitting chip is fixed by silver glue, which is conductive, so the red light-emitting chip only needs to be connected to another electrode through a metal wire, while the blue and green light-emitting chips It is fixed by insulating glue and needs to be connected to the electrodes at both ends through two metal wires. The connection between the three kinds of light-emitting chips and each electrode is not fixed, and it needs to be determined according to the solid crystal position of the light-emitting chip;

Glue potting step: Potting epoxy glue on the front of each lamp bead base C, the epoxy glue is cured to form a light-transmitting protective body F, and the protective body F covers the three light-emitting chips matched on each lamp bead base C D and the front side of the metal bracket 11 of each lamp bead base C;

Cutting step: cutting the bracket substrate A so that the common electrode 111, the first branch electrode 112, the second branch electrode 114 and the third branch electrode 115 of each lamp bead base C are disconnected from the substrate main body 10, thereby obtaining Independent small size LED lamp bead Z.

In a small-sized LED lamp bead manufacturing method of the present invention, the present invention directly grows on the back of the common electrode 111, the first branch electrode 112, the second branch electrode 113 and the third branch electrode 114 of the lamp bead bracket A1 respectively. The protruding common lamp pin 2, the first branch lamp pin 3, the second branch lamp pin 4 and the third branch lamp pin 5 do not need to bend the lamp bead bracket A1, thereby avoiding the The bead bracket A1 causes the water vapor intrusion channel to be formed between the lamp bead bracket A1, the plastic body B, and the protective body F; moreover, the present invention sets each plastic body B independently during injection molding, so that the present invention only needs to set the bracket when cutting. Cutting the substrate A does not need to cut the plastic body B and the protective body F, thereby avoiding the water vapor intrusion channel caused by the cutting of the plastic body B and the protective body F; The small-sized LED lamp bead Z produced by the bead manufacturing method can effectively prevent the water vapor intrusion channel generated by the small-sized LED lamp bead Z, so that the airtightness of the small-sized LED lamp bead Z is good.

In the present invention, in the metal substrate processing step, a plurality of through holes 12 may be formed on the metal substrate 1 by performing etching treatment, laser cutting treatment or punching treatment on the metal substrate 1, and then the metal substrate 1 is manufactured Several metal supports 11 and the substrate main body 10 connected with each metal support 11 .

In the present invention, in the step of preparing the lamp pin, the method of preparing the metal substrate for the lamp pin can specifically be:

Step 1: Coating ink on the entire surface of the metal substrate 1;

Step 2: Curing and cleaning the ink coated on the surface of the metal substrate 1; wherein, the ink coated on the area where the common lamp pin 2 needs to be grown on the back of each common electrode 111, and the ink on the back of each first branch electrode 112 needs to be The ink coated on the area where the first branch lamp pin 3 is grown, the ink coated on the area where the second branch lamp pin 4 needs to be grown on the back of each second branch electrode 113 , and the ink coated on the back of each third branch electrode 114 The ink coated on the area where the third branch lamp pin 5 needs to be grown is washed off, and the remaining ink coated on the surface of the metal substrate 1 is cured; specifically, a film sheet can be used to solidify the ink, and the ink can be cleaned through a cleaning solution;

Step 3: Electroplating the metal substrate 1, so that the area where the common lamp pin 2 needs to be grown on the back of each common electrode 111 grows the common lamp pin 2 by electroplating, and the first branch lamp pin 3 needs to be grown on the back of each first branch electrode 112 The first branch lamp pin 3 is grown by regional electroplating, and the second branch lamp pin 4 needs to be grown on the back of each second branch electrode 113. The area of the second branch lamp pin 118 is electroplated to grow the second branch lamp pin 118;

Step 4: Clean off all the ink coated on the surface of the metal substrate 1 to prevent the ink from affecting the bonding ability of the metal bracket 11 to the plastic body B and the protective body F.

In the present invention, the common lamp pin 2 , the first branch lamp pin 3 , the second branch lamp pin 4 and the third branch lamp pin 5 are all made of copper, and copper has good conductivity.

In the present invention, a protective layer preparation step may also be provided between the lamp pin preparation step and the injection molding step; the protective layer preparation step is: electroplating a conductive layer on the surface of the bracket substrate A by means of electroplating. The protective layer (not shown), the protective layer can protect the lamp bead bracket A1; the protective layer can include the first nickel layer, copper layer, second nickel layer and silver layer sequentially compounded with the metal substrate 1, wherein the conductive layer of the silver layer Good performance, good bonding ability of the nickel layer to ensure the stability of each connection.

As shown in Figures 1 to 8, in Embodiment 1 of the present invention, in the injection molding step, the plastic body B is a plastic lamp cup B1, and the plastic lamp cup B1 has a common electrode 111 separating the metal bracket 1 , the lamp cup dam B11 of the first branch electrode 112, the second branch electrode 113 and the third branch electrode 114, and the lamp cup wall B12 surrounding the metal bracket 11; and in the glue filling step, the protective body F is filled in the inner cavity of the lamp cup wall B12. The lamp cup wall B12 has a light concentrating effect and can improve the luminous effect of the small-sized LED lamp bead Z of the present invention; the lamp cup dam B11 protrudes from the front of the metal bracket 111, so that the lamp cup dam B11 can be fixed After the crystallization, it can prevent the short circuit caused by the migration of silver glue. The small-sized LED lamp bead Z manufactured by the manufacturing method of the first embodiment of the present invention may belong to the TOP type LED lamp bead.

As shown in FIG. 9 to FIG. 14, in the second embodiment of the present invention, in the injection molding step, the plastic body B is a plastic base B2, and the plastic base B2 has a common electrode 111 separating the metal bracket 1, a second The base dam B21 of a branch electrode 112, the second branch electrode 113, and the third branch electrode 114, the base dam B21 can protrude from the front of the metal support 11, so that the base dam B21 can prevent it after solid crystal Migration of silver glue causes a short circuit; and in the glue filling step, the protective body F can cover the plastic base B2. The small-sized LED lamp bead Z manufactured by the manufacturing method of the second embodiment of the present invention may belong to the CHIP type LED lamp bead.

The above-mentioned embodiments and drawings do not limit the form and style of the product of the present invention, and any appropriate changes or modifications made by those skilled in the art should be considered as not departing from the patent scope of the present invention.

Claims (10)

1. A method for manufacturing a small-size LED lamp bead is characterized by comprising the following steps: the method comprises the following steps:

a metal substrate processing step: manufacturing a plurality of metal supports and a substrate main body connected with each metal support on a metal substrate, wherein each metal support comprises a public electrode, a first branch electrode, a second branch electrode and a third branch electrode which are separated, and the public electrode, the first branch electrode, the second branch electrode and the third branch electrode of each metal support are respectively connected with the substrate main body;

the lamp base preparation step: carrying out lamp pin preparation treatment on the metal substrate to enable the back surfaces of the common electrode, the first branch electrode, the second branch electrode and the third branch electrode of each metal support to respectively grow a convex common lamp pin, a convex first branch lamp pin, a convex second branch lamp pin and a convex third branch lamp pin so as to obtain a support substrate with a plurality of lamp bead supports; the lamp bead support comprises a metal support, and a common lamp pin, a first branch lamp pin, a second branch lamp pin and a third branch lamp pin which are respectively grown on the back surfaces of the common electrode, the first branch electrode, the second branch electrode and the third branch electrode of the metal support;

injection molding: placing the support substrate in a mold cavity and growing a plurality of independent plastic bodies on the support substrate in an injection molding mode, so that each lamp bead support is combined with one independent plastic body to form a lamp bead base; the common electrode, the first branch electrode, the second branch electrode, the third branch electrode, the common lamp pin, the first branch lamp pin, the second branch lamp pin and the third branch lamp pin of the lamp bead support are at least partially exposed outside the plastic body, and the joint of the common electrode, the first branch electrode, the second branch electrode and the third branch electrode of the lamp bead support and the substrate main body is exposed outside the plastic body;

die bonding and wire bonding: carrying out die bonding and wire bonding operations on each lamp bead base, so that three light-emitting chips for respectively emitting red light, green light and blue light are fixed on the front surface of a common electrode of each lamp bead base, the three light-emitting chips are respectively connected with the front surfaces of a first branch electrode, a second branch electrode and a third branch electrode of the lamp bead base through metal wires, and the two light-emitting chips for emitting the green light and the blue light are also respectively connected with the front surface of the common electrode through the metal wires;

and (3) glue pouring: filling epoxy glue on the front surface of each lamp bead base, forming a light-transmitting protective body after the epoxy glue is cured, and covering the three light-emitting chips matched on each lamp bead base and the front surface of the metal bracket of each lamp bead base by the protective body;

cutting: and cutting the support substrate to disconnect the common electrode, the first branch electrode, the second branch electrode and the third branch electrode of each lamp bead base from the substrate main body, so as to obtain independent small-size LED lamp beads.

2. The method for manufacturing a small-size LED lamp bead of claim 1, wherein: in the metal substrate processing step, the metal substrate is subjected to etching treatment, laser cutting treatment or blanking treatment, so that a plurality of through holes are formed in the metal substrate, and a plurality of metal brackets and a substrate main body connected with each metal bracket are manufactured on the metal substrate.

3. The method for manufacturing a small-size LED lamp bead as claimed in claim 1, wherein: in the step of preparing the lamp pins, the mode of preparing and processing the lamp pins on the metal substrate is as follows:

the method comprises the following steps: coating ink on the whole surface of the metal substrate;

step two: curing and cleaning the ink coated on the surface of the metal substrate, wherein the ink coated on the area of the back of each common electrode where the common lamp pin needs to grow, the ink coated on the area of the back of each first branch electrode where the first branch lamp pin needs to grow, the ink coated on the area of the back of each second branch electrode where the second branch lamp pin needs to grow and the ink coated on the area of the back of each third branch electrode where the third branch lamp pin needs to grow are all cleaned, and the rest of the ink coated on the surface of the metal substrate is cured;

step three: electroplating the metal substrate to enable the region on the back of each common electrode where the common lamp pin needs to grow to be electroplated with the common lamp pin, the region on the back of each first branch electrode where the first branch lamp pin needs to grow to be electroplated with the first branch lamp pin, the region on the back of each second branch electrode where the second branch lamp pin needs to grow to be electroplated with the second branch lamp pin, and the region on the back of each second branch electrode where the second branch lamp pin needs to grow to be electroplated with the second branch lamp pin;

step four: and cleaning all ink coated on the surface of the metal substrate.

4. The method for manufacturing a small-sized LED lamp bead as claimed in claim 1 or 3, wherein: the public lamp pin, the first branch lamp pin, the second branch lamp pin and the third branch lamp pin are all made of copper materials.

5. The method for manufacturing a small-size LED lamp bead as claimed in claim 1 or 3, wherein: a protective layer preparation step is also arranged between the lamp pin preparation step and the injection molding step; the preparation steps of the protective layer are as follows: and electroplating a conductive protective layer on the surface of the support substrate in an electroplating mode.

6. The method for manufacturing a small-size LED lamp bead as claimed in claim 1, wherein: in the injection molding step, the plastic body is a plastic lamp cup which is provided with a common electrode separating the metal support, a lamp cup dam of a first branch electrode, a second branch electrode and a third branch electrode, and a lamp cup wall surrounding the metal support;

and in the step of filling the glue, the protective body is filled in the inner cavity of the wall of the lamp cup.

7. The method for manufacturing a small-sized LED lamp bead of claim 6, wherein: the lamp cup dam protrudes out of the front face of the metal support.

8. The method for manufacturing a small-size LED lamp bead as claimed in claim 1, wherein: in the step of injection molding, the plastic body is a plastic base having a base dam separating a common electrode, a first branch electrode, a second branch electrode and a third branch electrode of the metal support.

9. The method for manufacturing a small-sized LED lamp bead of claim 8, wherein: the base dam protrudes out of the front face of the metal support.

10. The method for manufacturing a small-size LED lamp bead of claim 1, wherein: the metal substrate is made of copper.

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