CN105514248A - High white light and low light decay LED and preparation method thereof - Google Patents

Abstract

This invention discloses a high-white-light, low-light-decay LED and its fabrication method. The LED includes an LED bracket, which is square and has a square groove inside. The square groove is divided into upper and lower layers. The edges of the lower and upper square grooves form a right-angled step. At each of the four corners of the upper square groove, a cylindrical hole is provided. The bottom surface of the cylindrical hole is flush with the bottom surface of the upper square groove, and the cylindrical hole has a notch that connects to the upper square groove. A small cylindrical hole is formed on the bottom surface of the cylindrical hole, which connects to the corner of the lower square groove. This invention's high-white-light, low-light-decay LED structure solves the problem of the yellow ring on the white light of LEDs and also solves the problem of brightness decay of the white light of LEDs.

Description

A kind of LED with high white light and low light attenuation and its preparation method

technical field

The invention relates to the field of LEDs, in particular to an LED with high white light and low light attenuation and a preparation method thereof.

Background technique

Light-emitting diode (LED) is a semiconductor light source. Compared with other light sources such as incandescent lamps, LEDs have many advantages. LEDs usually have longer life, better stability, faster switching characteristics, and lower energy consumption. As the LED as a new generation of light source has become more and more popular in people's lives, its application has become more and more extensive. In terms of synthesizing white light, the most common way is to place a wavelength conversion material, such as yellow phosphor, on a blue-emitting LED chip. The layer of wavelength conversion material on the LED chip will absorb some of the photons emitted by the LED and convert them down. (down-convert) to visible wavelengths of light, resulting in a two-color light source with blue and yellow wavelengths of light. If the correct ratio of yellow and blue light is produced, then the human eye perceives white light.

In the prior art, the packaging process of LEDs generally includes steps such as solid crystal, wire bonding, glue coating, and baking. In the glue coating step, phosphor powder is usually mixed in silica gel according to a certain proportion, and the phosphor powder is mixed with a dispensing device. The mixture with the glue is coated on the LED chip. However, the large particle size phosphor is prone to the problem of phosphor sedimentation during the glue dispensing process, which makes the distribution of the phosphor in the colloid uneven, resulting in the packaging of white LEDs. The occurrence of color deviation is commonly referred to as the yellow circle phenomenon. In other technical schemes, glue coating can also use conformal coating technology to coat a very uniform phosphor layer on the surface of the LED chip. However, due to the unequal distribution of the luminous intensity of the blue LED chip itself in space, it is difficult In terms of type coating, the distance of blue light with higher intensity value passing through the phosphor layer in the central area is shorter than the distance passing through the phosphor layer in the edge area, which results in a high color temperature value in the central area and a low color temperature value in the edge area, and the same color will appear. The problem of deviation. Most of the phosphor material is concentrated at the bottom of the groove of the bracket and the attachment of the LED chip. Long-term heating will cause brightness attenuation and affect the life of the LED.

As shown in Figure 1, the traditional white light LED packaging structure schematic diagram, the traditional white light LED is installed in the bowl cup of the first bracket 12 by the first LED chip 11, realizes the circuit through the first gold wire 13 and the pin of the first bracket 12 Connect, and then cover the surface of the first LED chip 11 with encapsulating colloid 14 , the encapsulating colloid 14 is generally made by mixing yellow-wavelength phosphor powder and encapsulant glue, and sometimes adding orange-red or green-wavelength phosphor powder. After the phosphor absorbs part of the blue light, it releases yellow light with a longer wavelength, and then the unabsorbed blue light and yellow light mix into white light. The light mixing of white light LED is not uniform enough, and the brightness is relatively low. Most of the phosphor material is concentrated at the bottom of the bracket groove and the attachment of the LED chip. Long-term heating will cause brightness attenuation, which will affect the life of the LED.

Contents of the invention

Aiming at the deficiencies in the prior art, the technical problem to be solved by the present invention is to provide a high white light low light attenuation LED and a preparation method thereof.

In order to solve the above technical problems, the present invention is realized through the following scheme: a high white light and low light decay LED, the LED includes an LED bracket, the LED bracket is square, and a square groove is opened inside it, and the square groove is divided into upper and lower Two layers, the square groove of the lower layer and the edge of the square groove of the upper layer form a right-angled step, and each of the four corners of the square groove of the upper layer is provided with a cylindrical hole, the bottom surface of the cylindrical hole is flat with the bottom surface of the upper square groove, and the There is a gap in the cylindrical hole, which communicates with the upper square groove, and a small cylindrical hole is opened on the bottom surface of the cylindrical hole, and the small cylindrical hole is connected to the corner of the lower square groove, and at the center of the bottom surface of the lower square groove, The LED chip is fixed, and the electrodes of the LED chip and the positive and negative poles of the LED bracket are connected by gold wires. On the upper square groove, an epoxy resin sheet is fixed, and in the cavity of the lower square groove at the bottom of the epoxy resin sheet , filled with encapsulating silica gel, and the encapsulating silica gel is filled in the cylindrical hole and the cylindrical small hole at the lower part of the cylindrical hole, and the lower layer of the epoxy resin sheet is coated with a fluorescent powder layer.

A method for preparing an LED with high white light and low light attenuation, the method comprising the following steps:

1) Select a square LED bracket and open two square grooves on the LED bracket. The square groove is divided into upper and lower layers. The lower square groove communicates with the upper square groove, forming a right-angled step on the edge of the two square grooves;

2) A cylindrical hole is provided at each of the four corners of the upper square groove, the bottom surface of the cylindrical hole is flat with the bottom surface of the upper square groove, and there is a gap in the cylindrical hole, which is connected to the upper square groove;

3) There is a small cylindrical hole on the bottom surface of the cylindrical hole, which is connected to the corner of the lower square groove, and the cylindrical small hole can also be connected to the bottom of the lower square groove;

4) After adding the epoxy resin powder into the fluorescent powder and stirring evenly, molded into a round cake shape, and cut into epoxy resin sheets corresponding to the size of the upper square groove;

5) Fix the crystal bonding wire at the center of the bottom surface of the lower square groove of the LED bracket, install the LED chip at the center of the bottom surface of the lower square groove of the LED bracket, and then connect the electrodes of the LED chip and the positive and negative poles of the LED bracket through gold wires stand up;

6) Place the epoxy resin sheet molded into a round cake in step 4) on the right-angled step at the square groove on the upper layer;

7) Fill the lower square groove cavity of the lower part of the epoxy resin sheet with the liquid encapsulating silicone through the four cylindrical holes and small cylindrical holes, and fill the four cylindrical holes and small cylindrical holes;

8) Press the edge of the LED bracket to fix the epoxy resin sheet. After the liquid packaging silicone is completely cured, the packaging is completed.

Compared with the prior art, the beneficial effect of the present invention is that the high white light and low light attenuation LED structure of the present invention solves the problem of the yellow circle of the LED white light, and also solves the problem of the brightness attenuation of the LED white light.

Description of drawings

FIG. 1 is a schematic diagram of a package structure of a white light LED in the prior art.

Fig. 2 is a schematic diagram of the structure of the LED bracket of the present invention.

Fig. 3 is a side sectional view of the LED bracket of the present invention.

Fig. 4 is a schematic diagram of Step 5 of the LED manufacturing method of the present invention.

Fig. 5 is a schematic diagram 1 of step 6 of the LED manufacturing method of the present invention.

Fig. 6 is a schematic diagram 2 of Step 6 of the LED manufacturing method of the present invention.

Fig. 7 is a schematic diagram of Step 7 of the LED manufacturing method of the present invention.

Fig. 8 is a schematic diagram of step 8 of the LED manufacturing method of the present invention.

Markings in the drawings: first LED chip 11, first bracket 12, first gold wire 13, encapsulant 14, LED bracket 1, rectangular step 2, cylindrical hole 3, gold wire 4, LED chip 5, epoxy resin slice 6.

detailed description

The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, so as to define the protection scope of the present invention more clearly.

Please refer to accompanying drawings 2-4, the present invention is a kind of LED with high white light and low light decay. Divided into upper and lower layers, the square groove of the lower layer and the edge of the square groove of the upper layer form a right-angled step 2, and a cylindrical hole 3 is respectively arranged at the four corners of the square groove of the upper layer. flat, and the cylindrical hole 3 has a gap, the gap communicates with the upper square groove, the bottom surface of the cylindrical hole 3 has a cylindrical small hole, and the cylindrical small hole is connected to the corner of the lower square groove, the lower square groove At the center of the bottom surface of the groove, an LED chip 5 is fixed, and the electrodes of the LED chip 5 and the positive and negative poles of the LED bracket 1 are connected by gold wires 4, and an epoxy resin sheet 6 is fixed on the upper square groove, The lower square groove cavity of the epoxy resin sheet 6 is filled with encapsulating silica gel 14, and the encapsulating silica gel 14 is filled in the cylindrical hole 3 and the cylindrical small hole at the bottom of the cylindrical hole 3, and the lower layer of the epoxy resin sheet 6 is coated with fluorescent coating. powder layer.

Example:

The preparation method of high white light and low light attenuation LED of the present invention, the method comprises the following steps:

1. As shown in Figure 2, select a square LED bracket and open two square grooves on the LED bracket. The square groove is divided into upper and lower layers. The lower square groove communicates with the upper square groove, forming a The rectangular step 2, the height of the lower square groove and the upper square groove are determined according to the actual LED chip power.

2. As shown in Figure 3, a cylindrical hole 3 is respectively arranged at the four corners of the upper square groove, the bottom surface of the cylindrical hole is flat with the bottom surface of the upper square groove, and the cylindrical hole 3 has a gap. The gap is connected to the upper square groove;

3. As shown in Figure 3, there is a small cylindrical hole on the bottom surface of the cylindrical hole 3, and the cylindrical small hole is connected to the corner of the lower square groove, and the cylindrical small hole can also be connected to the bottom of the lower square groove;

4. After adding the epoxy resin powder into the fluorescent powder and stirring evenly, molded into a round cake shape, cut into epoxy resin sheets corresponding to the size of the upper square groove, and coated the phosphor layer on one side of the epoxy resin sheet;

5. As shown in Figure 4, fix the crystal bonding wire at the center of the bottom surface of the lower square groove of the LED bracket 1, install the LED chip 5 at the center of the bottom surface of the lower square groove of the LED bracket 1, and then connect the electrodes of the LED chip 5 to the LED The positive and negative poles of the bracket 1 are connected by a gold wire 4;

6. As shown in Figure 5, place the epoxy resin sheet molded into a round cake in step 4 on the right-angled step 2 at the square groove on the upper layer;

7. As shown in Figure 6-7, fill the lower square groove cavity of the lower layer of the epoxy resin sheet through the four cylindrical holes 3 and small cylindrical holes through the liquid encapsulation silica gel 14, and fill the four cylindrical holes 3 and small cylindrical holes hole filled;

8. As shown in FIG. 8 , crimp the LED bracket 1 to fix the epoxy resin sheet. After the liquid encapsulation silicone 14 is completely cured, the encapsulation is completed.

The high white light and low light attenuation LED structure of the present invention solves the problem of the yellow circle of the white light of the LED, and also solves the problem of brightness attenuation of the white light of the LED.

The above is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the description of the present invention and the contents of the accompanying drawings, or directly or indirectly used in other related All technical fields are equally included in the scope of patent protection of the present invention.

Claims (2)

1. one kind high white light low light attenuation LED, described LED comprises LED support (1), it is characterized in that: described LED support (1) is for square, have square groove therein, this square groove divides two-layer up and down, the edge of lower floor's square groove and upper strata square groove forms a square step (2), in four bights of upper strata square groove, a cylindrical hole (3) is respectively set, the bottom surface of this cylindrical hole is equal with the bottom surface of upper strata square groove, and this cylindrical hole (3) has a breach, this breach is communicated with upper strata square groove, the bottom surface of described cylindrical hole (3) has a cylinder aperture, this cylinder aperture is communicated to the bight of lower floor's square groove, the center of described lower floor's square groove bottom surface, be fixed with LED chip (5), the electrode of described LED chip (5) and the both positive and negative polarity of LED support (1) are coupled together by gold thread (4), on the square groove of upper strata, be fixed with epoxy sheet (6), in lower floor's square groove cavity of epoxy sheet (6) bottom, be filled with packaging silicon rubber (14), and this packaging silicon rubber (14) is filled in the cylinder aperture of cylindrical hole (3) and cylindrical hole (3) bottom, described epoxy sheet (6) lower floor scribbles phosphor powder layer.

2., with a preparation method of high white light low light attenuation LED according to claim 1, it is characterized in that, the method comprises the following steps:

1), select square LED support, this LED support is opened two square grooves, this square groove divides two-layer up and down, and lower floor's square groove communicates with upper strata square groove, forms a square step (2) at two square groove edges;

2), in four bights of upper strata square groove, respectively arrange a cylindrical hole (3), the bottom surface of this cylindrical hole is equal with the bottom surface of upper strata square groove, and this cylindrical hole (3) has a breach, and this breach is communicated with upper strata square groove;

3), the bottom surface of cylindrical hole (3) has a cylinder aperture, and this cylinder aperture is communicated to the bight of lower floor's square groove, also cylinder aperture can be communicated to the bottom of lower floor's square groove;

4), after, by epoxy resin powder adding fluorescent material uniform stirring, after being molded into cake shape, cutting into the epoxy sheet corresponding with upper strata square groove size, and scribble phosphor powder layer in the one side of epoxy sheet;

5), at square groove bottom center of lower floor place's die bond bonding wire of LED support (1), LED chip (5) is arranged on square groove bottom center of the lower floor position of LED support (1), then the both positive and negative polarity of the electrode of LED chip (5) and LED support (1) is coupled together by gold thread (4);

6), the epoxy sheet after round pie that is molded in step 4) is placed on the square step (2) at square groove place, upper strata;

7), fill lower floor's square groove cavity of epoxy sheet bottom by liquid packaging silicon rubber (14) by four cylindrical holes (3), cylinder aperture, and four cylindrical holes (3), cylinder apertures are filled;

8), to LED support (1) carry out flanging, with fixing epoxy sheet, after liquid packaging silicon rubber (14) solidifies completely, encapsulation completes.