CN107180903A - A kind of CHIP LED products and preparation method - Google Patents

Abstract

The invention discloses a CHIP-LED manufacturing method, comprising the steps of: S1, making a circuit layer and a conductive hole on a substrate; the circuit layer includes a front circuit layer on the front of the substrate and a back circuit layer on the back of the substrate; S2, Plasma cleaning the front of the substrate; S3, fixing the LED chip on the circuit layer on the front of the substrate; S4, spraying a layer of adhesive with nano-scale or micron-scale solid particles on the front of the substrate to form an adhesive layer. The agent is a thermoplastic solvent glue; S5, covering the encapsulation glue on the adhesive layer, and packaging the substrate, the front circuit layer, and the LED chip into a semi-finished product; S6, after the adhesive layer is cured and dried, cool it and use a cutting The equipment cuts the semi-finished product into individual CHIP‑LEDs. As well as a CHIP-LED product, the encapsulation glue is provided with a layer of adhesive layer with nano-scale or micron-scale solid particles on one side close to the substrate. The manufacturing method and the CHIP-LED product of the present invention have better air tightness and moisture resistance.

Description

A kind of CHIP-LED product and manufacturing method

technical field

The invention relates to the technical field of LED packaging, in particular to a CHIP-LED product and a manufacturing method.

Background technique

With the continuous improvement of indoor display application technology, indoor small-pitch products will become the main technology expansion space in the future. In the prior art, small-pitch LED devices are generally CHIP-LEDs, whose length and width are less than or equal to 1 mm. After the front side of the substrate and the front circuit layer and the LED chip arranged on the front side of the substrate are packaged together through packaging glue, then through cut by cutting equipment. The encapsulation material is generally made of thermosetting plastics such as epoxy resin or silica gel. After cutting, the encapsulation adhesive of the CHIP-LED is prone to detachment from the substrate, especially for traditional LEDs, the circuit lines on the front of the substrate More, it is easier for the encapsulation glue to separate from the front of the substrate, and it is difficult to repair after separation, resulting in poor air tightness and moisture resistance of CHIP-LED products, and a high failure rate during use.

Contents of the invention

The technical problem to be solved by the present invention is: to provide a CHIP-LED product and its manufacturing method, which can enhance the adhesive force between the packaging glue and the substrate, prevent the packaging glue from being separated from the substrate after cutting, and ensure that the CHIP-LED product has better Air tightness and moisture resistance.

In order to solve the above-mentioned technical problems, the technical solution one that the present invention adopts is:

A method for making a CHIP-LED, comprising the steps of:

S1, making a circuit layer and conductive holes on the substrate; the circuit layer includes a front circuit layer on the front of the substrate and a back circuit layer on the back of the substrate;

S2, performing plasma cleaning on the front side of the substrate;

S3, fixing the LED chip on the circuit layer on the front side of the substrate;

S4. Spraying a layer of adhesive with nanoscale or micron-scale solid particles on the front of the substrate to form an adhesive layer, and the adhesive is a thermoplastic solvent glue;

S5. Cover the adhesive layer with encapsulation glue, and package the substrate, the front circuit layer, and the LED chip into a semi-finished product;

S6. After the adhesive layer is cured and dried, it is cooled, and the semi-finished product is cut into individual CHIP-LEDs with a cutting device.

In order to solve the above-mentioned technical problems, the technical scheme two that the present invention adopts is:

A CHIP-LED product, comprising a substrate, an encapsulating glue covering the front of the substrate, a front circuit layer and an LED chip arranged between the substrate and the encapsulating glue, the encapsulating glue is provided with a layer of solid particles of nanometer level or micron-level adhesive layer, the adhesive layer is a thermoplastic solvent glue.

The beneficial effects of the present invention are: the present invention breaks the conventional encapsulation method of directly covering the encapsulation glue on the front of the substrate, and adds a layer of adhesive layer of thermoplastic solvent glue whose solid particles are nanoscale or micron scale between the encapsulation glue and the substrate , so that the encapsulant is not directly bonded to the substrate and the front circuit layer of the substrate, but is bonded to the adhesive layer respectively, the adhesive force between the adhesive layer and the substrate and the front circuit layer, and the adhesion between the adhesive layer and the front circuit layer The adhesive force of the encapsulant is greater than that of the traditional encapsulant and the substrate and the front circuit layer, so compared with the prior art, the encapsulation method of the present invention can effectively avoid the separation of the substrate and the encapsulant, even if Separation can also cause the adhesive layer to be rebonded and repaired in time; and the present invention performs plasma cleaning on the substrate before spraying the adhesive, which can further strengthen the adhesion between the substrate and the metal circuit layer on the front of the substrate and the adhesive. The combined effect ensures that the prepared CHIP-LED products have good air tightness and moisture resistance, and improves their reliability and service life during use.

Description of drawings

FIG. 1 is a schematic diagram of the front structure of a CHIP-LED product according to Embodiment 3 of the present invention;

Fig. 2 is a schematic diagram of the rear structure of the CHIP-LED product according to Embodiment 3 of the present invention;

Fig. 3 is a cross-sectional view of a CHIP-LED product according to Embodiment 3 of the present invention.

Label description:

1. Substrate; 2. Front circuit layer; 3. Back circuit layer; 4. Conductive hole; 5. Common electrode identification; 6. LED chip; 7. Key and wire; 8. Adhesive layer;

detailed description

In order to describe the technical content, achieved goals and effects of the present invention in detail, the following descriptions will be made in conjunction with the embodiments and accompanying drawings.

The most critical idea of the present invention is: before covering encapsulant 9, first spray a layer of adhesive with solid particles of nanoscale or micron scale on the front of substrate 1, so that the CHIP-LED product after cutting has better airtightness sex and moisture resistance.

A method for making a CHIP-LED, comprising the steps of:

S1, making a circuit layer and conductive holes 4 on the substrate 1; the circuit layer includes a front circuit layer 2 on the front of the substrate 1 and a back circuit layer 3 on the back of the substrate 1;

S2, performing plasma cleaning on the front surface of the substrate 1;

S3, fixing the LED chip 6 on the front circuit layer 2 of the substrate 1;

S4. Spraying a layer of adhesive with nanoscale or micron-scale solid particles on the front of the substrate 1 to form an adhesive layer 8, the adhesive being a thermoplastic solvent glue;

S5, covering the encapsulation glue 9 on the adhesive layer 8, and encapsulating the substrate 1, the front circuit layer 2, and the LED chip 6 into a semi-finished product;

S6. After the adhesive layer 8 is solidified and dried, it is cooled, and the semi-finished product is cut into individual CHIP-LEDs with a cutting device. It can be seen from the above description that the beneficial effect of the present invention is that the present invention breaks the conventional encapsulation method of directly covering the encapsulation glue on the front of the substrate, and adds a layer of thermoplastic solvent glue with solid particles of nanometer or micrometer scale between the encapsulation glue and the substrate The adhesive layer, so that the encapsulation glue is not directly bonded to the substrate and the front circuit layer of the substrate, but is bonded to the adhesive layer respectively, the adhesive force of the adhesive layer to the substrate and the front circuit layer, and The adhesion between the adhesive layer and the encapsulation glue is greater than the adhesion between the traditional encapsulation glue and the substrate and the front circuit layer. Therefore, compared with the prior art, the encapsulation method of the present invention can effectively avoid the occurrence of phase contact between the substrate and the encapsulation glue. Even if there is a separation phenomenon, the adhesive layer can be rebonded and repaired in time; and the present invention performs plasma cleaning on the substrate before spraying the adhesive, which can further strengthen the connection between the substrate and the metal circuit layer on the front of the substrate. The bonding effect of the adhesive ensures that the prepared CHIP-LED product has good air tightness and moisture resistance, and improves its reliability and service life during use.

Further, the spraying range of the adhesive layer 8 is the entire front of the substrate 1 or the area other than the solid crystal area on the front of the substrate 1. When the spraying range is the entire front of the substrate 1, a transparent adhesive is selected; when spraying When the range is the area on the front surface of the substrate 1 other than the crystal-bonding area, a transparent or opaque adhesive is selected.

It can be seen from the above description that the spraying range and the selection type of the adhesive can ensure that the addition of the adhesive layer will not affect the normal light emission of the CHIP-LED product.

Further, the spraying range is the entire front of the substrate 1, and the refractive index of the adhesive is greater than 1.45.

It can be seen from the above description that when the entire surface is coated, the adhesive with a high refractive index can be used to guide more light from the LED chip, reduce the heat generation of the LED chip, and further increase the reliability and service life of the LED.

Further, the adhesive is one or more of acrylic resin, polyacrylate, polyvinyl acetal and polymethacrylate.

Further, the spraying thickness of the adhesive layer 8 is 1-10 μm.

Further, the LED chip 6 is a front-mount chip or a flip-chip. When the LED chip 6 is a front-mount chip, the specific steps for fixing the LED chip 6 are: dispensing glue to fix the LED chip 6, and using a gold wire or a silver alloy wire to fix the LED chip 6. Bond the wire bonding area of the front circuit layer 2 of the substrate 1 with the electrodes of the LED chip 6; when the LED chip 6 is a flip chip, the specific steps for fixing the LED chip 6 are: directly solder the LED chip 6 to the substrate 1 The front line layer 2.

Please refer to FIG. 1 to FIG. 3 , a CHIP-LED product includes a substrate 1, an encapsulant 9 covering the front of the substrate 1, and a front circuit layer 2 and an LED chip 6 arranged between the substrate 1 and the encapsulant 9. A side of the packaging glue 9 close to the substrate 1 is provided with a layer of adhesive layer 8 with solid particles of nanometer or micrometer size, and the adhesive layer 8 is a thermoplastic solvent glue.

It can be seen from the above description that the beneficial effect of the present invention is that: the CHIP-LED product of the present invention adds a layer of adhesive layer with solid particles of nanoscale or micron scale between the front of the substrate and the encapsulant, which can ensure that the CHIP-LED product It has better airtightness during use, so that there will be no gap between the encapsulant and the substrate, preventing the internal components from getting wet, and has better reliability and longer service life.

Further, the encapsulating glue 9 is mixed with melanin or glass bead powder.

From the above description, it can be seen that the encapsulation glue covers the LED chip 6, and melanin or glass bead powder is mixed into the encapsulation glue, which can improve the luminous contrast of LED products, make the emitted light softer, and have a better luminous effect.

Further, the thickness of the substrate 1 is 0.1-0.5mm, and the material is BT board, FR4 substrate, ceramic substrate, aluminum substrate or copper substrate.

Further, the substrate 1 also includes a conductive hole 4 and a back circuit layer 3 arranged on the back of the substrate 1. The hole wall and the periphery of the conductive hole 4 are metal plating, and the conductive hole 4 is provided with a filler. The conductive hole 4 communicates with the front circuit layer 2 and the back circuit layer 3 .

Embodiment one

Embodiment 1 of the present invention is: a method for manufacturing a CHIP-LED, comprising the following steps:

S1. Make a circuit layer and a conductive hole 4 on the substrate 1, the circuit layer includes a front circuit layer 2 on the front of the substrate 1 and a back circuit layer on the back of the substrate 1; the hole wall and the periphery of the conductive hole 4 are For the metal plating layer, fillers are arranged in the conductive hole 4 , and the conductive hole 4 communicates with the front circuit layer 2 and the back circuit layer 3 .

S2, performing plasma cleaning on the front side of the substrate 1;

S3. Fix the LED chip 6 on the crystal-bonding area of the front circuit layer 2 of the substrate 1; the LED chip 6 includes a red chip, a green chip, and a blue chip, and the number of red chips: green chips: blue chips The ratio is 1:1:1.

The LED chip 6 is a front-mounted chip, and the specific steps for fixing the LED chip 6 are: dispensing glue to fix the LED chip 6, and bonding the wire bonding area of the front circuit layer 2 of the substrate 1 to the electrode of the LED chip 6 with a gold wire or a silver alloy wire. with.

S4. Spraying a layer of adhesive with nanoscale or micron-scale solid particles on the front surface of the substrate 1 to form an adhesive layer 8, the adhesive is a thermoplastic solvent glue.

The adhesive is one or more of acrylic resin, polyacrylate, polyvinyl acetal and polymethacrylate. In this embodiment, the adhesive includes acrylic resin and some mixing agents, the refractive index of the adhesive is 1.5, and the spray thickness of the adhesive layer 8 is 10 μm. The spraying range of the layer 8 is the entire front of the substrate 1, and the adhesive is colorless and transparent, so as to ensure that the existence of the adhesive layer 8 will not only weaken the luminous effect of the LED chip 6, but can instead absorb more light. Derived from the LED chip 6, the calorific value of the LED chip 6 is reduced, and the reliability and service life of the LED are further increased.

S5. Cover the front of the substrate 1 with the encapsulating glue 9 through a compression molding process, so that the substrate 1, the front circuit layer 2, and the LED chip 6 are packaged as a semi-finished product; the encapsulating glue 9 is mixed with melanin or glass bead powder, which can increase The luminous contrast of the LED chip 6 makes the emitted light softer. The surface shape of the encapsulant 9 may be a flat mirror surface or a frosted surface, or other shapes such as microlenses.

S6. After the adhesive layer 8 is cured and dried, it is cooled, and the semi-finished product is cut into individual CHIP-LEDs with a cutting device to obtain a CHIP-LED product as shown in FIG. 1 .

Embodiment two

Embodiment 2 of the present invention is: a method for manufacturing a CHIP-LED, comprising the following steps:

S1. Make a circuit layer and a conductive hole 4 on the substrate 1, the circuit layer includes a front circuit layer 2 on the front of the substrate 1 and a back circuit layer on the back of the substrate 1; the hole wall and the periphery of the conductive hole 4 are For the metal plating layer, fillers are arranged in the conductive hole 4 , and the conductive hole 4 communicates with the front circuit layer 2 and the back circuit layer 3 .

S2, performing plasma cleaning on the front side of the substrate 1;

S3. Fix the LED chip 6 on the crystal-bonding area of the front circuit layer 2 of the substrate 1; the LED chip 6 includes a red chip, a green chip, and a blue chip, and the number of red chips: green chips: blue chips The ratio is 1:1:1.

The LED chip 6 is a flip chip, and the specific steps for fixing the LED chip 6 are: directly soldering the LED chip 6 to the circuit layer 2 on the front side of the substrate 1 .

S4. Spraying a layer of adhesive with nanoscale or micron-scale solid particles on the front surface of the substrate 1 to form an adhesive layer 8, the adhesive is a thermoplastic solvent glue.

The adhesive is one or more of acrylic resin, polyacrylate, polyvinyl acetal and polymethacrylate. In this embodiment, the adhesive includes polyacrylate and some mixing agents, the refractive index of the adhesive is 1.45, the spray thickness of the adhesive layer 8 is 1 μm, and the adhesive The spraying range of the mixture layer 8 is the area on the front surface of the substrate 1 except the die-bonding area, so as to ensure that the presence of the adhesive layer 8 will not affect the luminous effect of the LED chip 6 .

S5. Cover the front of the substrate 1 with the encapsulating glue 9 through a compression molding process, so that the substrate 1, the front circuit layer 2, and the LED chip 6 are packaged as a semi-finished product; the encapsulating glue 9 is mixed with melanin or glass bead powder, which can increase The luminous contrast of the LED chip 6 makes the emitted light softer. The surface shape of the encapsulant 9 may be a flat mirror surface or a frosted surface, or other shapes such as microlenses.

S6. After the adhesive layer 8 is cured and dried, it is cooled, and the semi-finished product is cut into individual CHIP-LEDs with a cutting device to obtain a CHIP-LED product as shown in FIG. 1 .

Embodiment Three

Please refer to Figure 1, the third embodiment of the present invention is: a CHIP-LED product, including a substrate 1 and an LED chip 6, the material of the substrate 1 can be BT board, FR4 substrate, ceramic substrate, aluminum substrate or copper substrate , this embodiment is preferably a BT board, and the thickness of the BT board is 0.1-0.5 mm. The substrate 1 is provided with a circuit layer and a conductive hole 4, and the circuit layer includes a front circuit layer 2 on the front of the substrate 1 and a back circuit layer on the back of the substrate 1; the hole wall and the hole periphery of the conductive hole 4 are For the metal plating layer, fillers are arranged in the conductive hole 4 , and the conductive hole 4 communicates with the front circuit layer 2 and the back circuit layer 3 . As shown in FIG. 2 , the back of the substrate 1 is also provided with a common electrode mark 5 (common anode type CHIP-LED mark anode, common cathode type CHIP-LED mark cathode), marked as green oil or metal. The front circuit layer 2 includes a crystal-bonding area and a bonding wire area, wherein an LED chip 6 is bonded to the crystal-bonding area, and the LED chip 6 includes a red chip, a green chip, and a blue chip, and the red chip: a green chip : The ratio of the number of Blu-ray chips is 1:1:1. Bonds and wires 7 are connected between the wire bonding area and the LED chip 6 .

Please refer to FIG. 3 , the CHIP-LED product also includes an encapsulant 9 and an adhesive layer 8 covering the front surface of the substrate 1, the adhesive layer 8 is arranged between the encapsulant 9 and the front surface of the substrate 1, and the adhesive The agent layer 8 is formed by a layer of solid particles that are nanoscale or micron-scale adhesives. The adhesive is a thermoplastic solvent glue. The adhesive force and adhesion between the adhesive layer 8 and the substrate 1 The adhesive force between the agent layer 8 and the encapsulant 9 is greater than the adhesive force between the encapsulant 9 and the substrate 1 . The adhesive layer 8 is composed of one or more of acrylic resins, polyacrylates, polyvinyl acetal and polymethacrylates, preferably acrylic resins in this embodiment. The encapsulation glue 9 is mixed with melanin or pearl powder, which can increase the luminous contrast of LED products and make the luminescence softer; the surface shape of the encapsulation glue 9 can be a flat mirror surface or a frosted surface, or other shapes such as microlenses.

In summary, in the CHIP-LED manufacturing method and the CHIP-LED product provided by the present invention, a layer of adhesive layer 8 with solid particles of nanoscale or micron scale is added between the encapsulation glue 9 and the substrate 1, which can make the encapsulation glue 9 and the substrate 1 have greater adhesion, which effectively prevents the detachment of the packaging glue 9 and the substrate 1 after cutting, so that the product has better air tightness and moisture resistance.

The above description is only an embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent transformations made by using the description of the present invention and the contents of the accompanying drawings, or directly or indirectly used in related technical fields, are all included in the same principle. Within the scope of patent protection of the present invention.

Claims (10)

1. A CHIP-LED manufacturing method, characterized in that, comprising steps: S1, making a circuit layer and conductive holes on the substrate; the circuit layer includes a front circuit layer on the front of the substrate and a back circuit layer on the back of the substrate; S2, performing plasma cleaning on the front side of the substrate; S3, fixing the LED chip on the circuit layer on the front side of the substrate; S4. Spraying a layer of adhesive with nanoscale or micron-scale solid particles on the front of the substrate to form an adhesive layer, and the adhesive is a thermoplastic solvent glue; S5. Cover the adhesive layer with encapsulation glue, and package the substrate, the front circuit layer, and the LED chip into a semi-finished product; S6. After the adhesive layer is cured and dried, it is cooled, and the semi-finished product is cut into individual CHIP-LEDs with a cutting device. 2. The CHIP-LED manufacturing method according to claim 1, wherein the spraying range of the adhesive layer is the entire front of the substrate or an area other than the die-bonding area on the front of the substrate, when the spraying range is the entire substrate For the front side, use a transparent adhesive; when the spraying range is on the front side of the substrate except for the die-bonding area, use a transparent or opaque adhesive. 3. The manufacturing method of CHIP-LED according to claim 1, characterized in that, the spraying range is the entire front surface of the substrate, and the refractive index of the adhesive is greater than 1.45. 4. The CHIP-LED manufacturing method according to claim 1, wherein the adhesive is one or more of acrylic resins, polyacrylates, polyvinyl acetals and polymethacrylates. kind. 5. The manufacturing method of CHIP-LED according to claim 1, characterized in that, the spraying thickness of the adhesive layer is 1-10 μm. 6. The CHIP-LED manufacturing method according to claim 1, wherein the LED chip is a front-mount chip or a flip-chip, and when the LED chip is a front-mount chip, the specific steps of fixing the LED chip are: Fix the LED chip with glue, and use gold wire or silver alloy wire to bond the bonding wire area of the front circuit layer of the substrate with the electrode of the LED chip; when the LED chip is a flip chip, the specific steps for fixing the LED chip are: put the LED chip Solder directly to the front circuit layer of the substrate. 7. A CHIP-LED product, comprising a substrate, an encapsulant covering the front of the substrate, and a front circuit layer and an LED chip arranged between the substrate and the encapsulant, characterized in that the encapsulant is disposed near one side of the substrate There is a layer of adhesive layer whose solid particles are nanoscale or micronscale, and the adhesive layer is thermoplastic solvent glue. 8. The CHIP-LED product according to claim 7, wherein the thickness of the substrate is 0.1-0.5mm, and the material is BT board, FR4 substrate, ceramic substrate, aluminum substrate or copper substrate. 9. The CHIP-LED product according to claim 7, characterized in that, the encapsulating glue is doped with melanin or glass bead powder. 10. The CHIP-LED product according to claim 7, characterized in that, the substrate further includes a conductive hole and a back circuit layer arranged on the back of the substrate, the hole wall and the periphery of the conductive hole are metal plating, conductive A filler is arranged in the hole, and the conductive hole communicates with the front circuit layer and the back circuit layer.