A method for preparing quantum dot LED lamp beads

Abstract

The present invention relates to a quantum dot LED lamp bead, comprising a substrate, a blue light chip, a quantum dot mixture, silica gel, and a base film. The substrate is provided with a receiving cavity. The blue light chip, the quantum dot mixture, the silica gel, and the base film are sequentially positioned in the receiving cavity from bottom to top. The coating area of ​​the quantum dot mixture is greater than or equal to the area of ​​the blue light chip. The silica gel seals the receiving cavity and encapsulates the quantum dot mixture and the blue light chip. The beneficial effect is that the color gamut of the quantum dot LED lamp bead prepared using the quantum dot mixture is greater than 110% NTSC. The amount of quantum dot mixture used corresponds to one blue light chip, reducing the amount of quantum dots used to reduce the cost of the quantum dot LED lamp bead and reducing the size of the quantum dot LED lamp bead. The smaller quantum dot LED lamp bead serves as the smallest unit for preparing an LED backlight module, improving flexibility and allowing the distribution and quantity of the quantum dot LED lamp beads to be planned as needed. The use of fewer quantum dot LED lamp beads reduces the amount of quantum dots required for the LED backlight module, thereby reducing the cost of the LED backlight module.

Description

Technical Field

[0001] The present invention relates to the field of LED technology, and in particular to a quantum dot LED lamp bead and a preparation method thereof. Background Art

[0002] With the development of technology, the LED backlight display field has generally begun to require a high color gamut. Generally, a color gamut value greater than 72% NTSC is considered a high color gamut. Currently, display modules that can achieve a high color gamut in LED backlight modules include OLED (organic light-emitting diode), phosphor LED, and quantum dot LED. Among them, LED backlight modules made with OLED can achieve a color gamut greater than 100% NTSC, but due to technical and production process limitations, their cost is high and the yield rate is low. LED backlight modules made with phosphor LED can achieve a color gamut value of up to 95% NTSC, but due to production process limitations, their yield rate is also low. LED backlight modules made with quantum dot LEDs can achieve a color gamut greater than 110% NTSC, but require a quantum dot LED display module of the same size as the LED backlight module. The high cost of quantum dots leads to a higher price for LED backlight modules made with them and lower market acceptance. Summary of the Invention

[0003] (1) Technical issues to be resolved

[0004] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a quantum dot LED display lamp bead and a preparation method thereof, which solves the technical problem of high production cost of the existing display module capable of achieving a high color gamut.

[0005] (2) Technical solution

[0006] In order to achieve the above objectives, the main technical solutions adopted by the present invention include:

[0007] In a first aspect, an embodiment of the present invention provides a quantum dot LED lamp bead, comprising a substrate, a blue light chip, a quantum dot mixture, silica gel and a base film, wherein a receiving cavity is provided on the substrate;

[0008] The blue light chip, the quantum dot mixture, the silica gel and the base film are sequentially positioned in the accommodating cavity from bottom to top;

[0009] The coating area of ​​the quantum dot mixture is greater than or equal to the area of ​​the blue light chip;

[0010] The silica gel seals the containing cavity and covers the quantum dot mixture and the blue light chip.

[0011] According to the present invention, the quantum dot mixture includes red quantum dots and green quantum dots.

[0012] According to the present invention, the components of the quantum dot mixture include cadmium sulfide, cadmium selenide, cadmium telluride, zinc selenide, gallium nitride and / or indium arsenide.

[0013] According to the present invention, the accommodating cavity is a truncated cone, and the cross-sectional area of ​​the accommodating cavity gradually increases from the blue light chip toward the silica gel.

[0014] According to the present invention, the blue light chip is a flip chip, and the blue light chip includes an electrode and a P-type GaN layer, an emission layer, an N-type GaN layer and a substrate arranged in sequence from bottom to top;

[0015] The top of the electrode abuts against the P-type GaN layer, the bottoms of the P-type GaN layer and the motor abut against the bottom of the accommodating cavity, and the bumps arranged on the electrode are connected to the bottom of the accommodating cavity.

[0016] In a second aspect, the present invention further provides a method for preparing a quantum dot LED lamp bead, which is used to prepare a quantum dot LED lamp bead, and comprises the following steps in sequence:

[0017] S1: placing the blue light chip in the receiving cavity on the substrate;

[0018] S2: coating the quantum dot mixture and the silica gel on the base film in sequence from bottom to top;

[0019] The coating area of ​​the quantum dot mixture is greater than or equal to the area of ​​the blue light chip, the silica gel covers the quantum dot mixture, and the silica gel and the quantum dot mixture form quantum dot glue;

[0020] S3: After turning the base film 180 degrees, the quantum dot glue is put into the receiving cavity, the silica gel seals the receiving cavity, and the quantum dot mixture and the blue light chip are arranged opposite to each other;

[0021] S4: Combining the quantum dot glue with the blue light chip and the receiving cavity respectively by vacuum hot pressing;

[0022] S5: After the quantum dot material and the silicone are solidified, cutting along the substrate to form a plurality of substrates, each substrate comprising one accommodating cavity, to form the quantum dot LED lamp beads.

[0023] According to the present invention, step S3 further includes: the silica gel is flush with the accommodating cavity.

[0024] According to the present invention, step S4 further includes: cutting the substrate using automatic cutting equipment.

[0025] (3) Beneficial effects

[0026] The beneficial effects of the present invention are as follows: the quantum dot LED lamp beads proposed in the embodiment of the present invention include a substrate, a blue light chip, a quantum dot mixture, silica gel and a base film.

[0027] At least one cavity is provided on the substrate. The blue light chip, quantum dot mixture, silicone gel, and base film are positioned within the cavity, sequentially from bottom to top. The coating area of ​​the quantum dot mixture is ensured to be greater than or equal to the area of ​​the blue light chip. The silicone gel seals the cavity and coats the quantum dot mixture and blue light chip. When stimulated by the blue light chip, the quantum dot mixture emits full-color light.

[0028] The quantum dot mixture and blue light chip are coated with silica gel to isolate them from external water vapor, preventing the quantum dot mixture from failing and light loss from the blue light chip due to contact with water vapor. The prior art generally uses a structure where two layers of silica gel coat the quantum dot mixture. Light emitted by the blue light chip must pass through both layers of silica gel, resulting in low light transmittance. However, in this application, only one layer of silica gel is provided, thereby increasing the light transmittance of the blue light chip.

[0029] This quantum dot LED lamp bead is provided with a receiving cavity, and a blue light chip, a quantum dot mixture, a silica gel, and a base film are sequentially arranged in the receiving cavity from bottom to top. The coating area of ​​the quantum dot mixture is greater than or equal to the area of ​​the blue light chip, so that the amount of quantum dot mixture used in each quantum dot LED lamp bead after molding corresponds to one blue light chip, thereby reducing the amount of quantum dots used and thus reducing the production cost of the quantum dot LED lamp bead, and can also reduce the volume of the quantum dot LED lamp bead. Using the smaller quantum dot LED lamp bead as the minimum unit for preparing the LED backlight module improves the flexibility in preparing the LED backlight module and can plan the distribution method and number of quantum dot LED lamp beads as needed. Compared with the quantum dot LED display module of the same size as the LED backlight module in the prior art, the amount of quantum dot LED lamp bead is smaller, thereby reducing the amount of quantum dots required to produce an LED backlight module, thereby reducing the production cost of the LED backlight module.

[0030] At the same time, the quantum dot LED lamp bead adopts a quantum dot mixture so that the color gamut of the quantum dot LED lamp bead prepared therefrom is greater than 110% NTSC.

[0031] In addition, the preparation method of the quantum dot LED lamp beads is simple and has fewer steps, thereby improving the molding yield of the quantum dot LED lamp beads. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 Schematic diagram of the substrate of the quantum dot LED lamp beads of the present invention;

[0033] Figure 2 for Figure 1Schematic diagram of the substrate in;

[0034] Figure 3 for Figure 2 The main view;

[0035] Figure 4 This is a front view of the quantum dot LED lamp bead of the present invention;

[0036] Figure 5 for Figure 4 The blue light chip in it.

[0037] [Description of Reference Numerals]

[0038] 1: substrate; 11: base plate; 12: receiving cavity;

[0039] 2: Blue light chip; 21: Electrode; 22: P-type GaN layer; 23: Emitting layer; 24: N-type GaN layer; 25: Substrate;

[0040] 3: Quantum dot film. DETAILED DESCRIPTION

[0041] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below with reference to the accompanying drawings and through specific embodiments. Figure 4 The orientation is referenced.

[0042] Reference Figure 4 As shown, the quantum dot LED lamp bead proposed in an embodiment of the present invention includes a substrate 11, a blue light chip 2, a quantum dot mixture, silica gel and a base film.

[0043] Reference Figure 2-4 As shown, at least one receiving cavity 12 is provided on the substrate 11. The blue light chip 2, quantum dot mixture, silica gel, and base film are positioned in order from bottom to top within the receiving cavity 12. The coating area of ​​the quantum dot mixture is greater than or equal to the area of ​​the blue light chip 2. The silica gel is used to seal the receiving cavity 12 and coat the quantum dot mixture and blue light chip 2. When excited by the blue light chip 2, the quantum dot mixture emits full-color light.

[0044] The quantum dot mixture and blue light chip 2 are coated with silica gel to isolate them from external water vapor, preventing the quantum dot mixture from failing and light loss from the blue light chip 2 due to contact with water vapor. The prior art generally uses a two-layer silica gel coating structure for the quantum dot mixture. Light emitted by the blue light chip 2 must pass through both layers of silica gel, resulting in low light transmittance. In this application, only one layer of silica gel is provided, thereby increasing the light transmittance of the blue light chip 2. The silica gel also protects the quantum dot mixture and the blue light chip 2.

[0045] The quantum dot LED lamp bead is provided with a receiving cavity 12, and a blue light chip 2, a quantum dot mixture, a silica gel, and a base film are sequentially arranged in the receiving cavity 12 from bottom to top. The coating area of ​​the quantum dot mixture is greater than or equal to the area of ​​the blue light chip 2, so that the amount of quantum dot mixture used in each quantum dot LED lamp bead after molding corresponds to one blue light chip 2, thereby reducing the amount of quantum dots used and thus reducing the production cost of the quantum dot LED lamp bead, and can also reduce the volume of the quantum dot LED lamp bead. Using the smaller quantum dot LED lamp bead as the minimum unit for preparing the LED backlight module improves the flexibility in preparing the LED backlight module and can plan the distribution method and number of the quantum dot LED lamp beads as needed. Compared with the quantum dot LED display module of the same size as the LED backlight module in the prior art, the amount of quantum dot LED lamp beads used is smaller, thereby reducing the amount of quantum dots required to produce one LED backlight module, thereby reducing the production cost of the LED backlight module.

[0046] At the same time, the quantum dot LED lamp bead adopts a quantum dot mixture so that the color gamut of the quantum dot LED lamp bead prepared therefrom is greater than 110% NTSC.

[0047] Furthermore, the base film is made of materials such as PET (polyethylene terephthalate) or PO (propylene oxide).

[0048] Reference Figure 1-Figure 3 As shown, further, as an example, a substrate 1 with a length of 24mm and a width of 30mm is used, and 80 accommodating cavities 12 are set at intervals on the substrate 1. After the blue light chip 2, quantum dot mixture and silica gel are placed in the accommodating cavities 12 from bottom to top, multiple substrates 11 are cut along the substrate 1. Each substrate 11 contains a accommodating cavity 12. The diameter of the open end of the accommodating cavity 12 is 2.1mm. The length and width of the substrate 11 are both 3mm, so as to form 80 quantum dot LED lamp beads with a length and width of 3mm. The above values, the number of accommodating cavities 12 set on each substrate 1, and the arrangement of the accommodating cavities 12 are all examples and are not limited here. The specific values ​​can be set according to actual needs.

[0049] The substrate 1 is made of ceramic, EMC (epoxy molding compound), SMC (silicone molding compound), PCT (poly (1,4-cyclohexanedimethanol terephthalate)) or copper.

[0050] Furthermore, the quantum dot mixture includes red quantum dots and green quantum dots. The ratio of the red quantum dots to the green quantum dots is set so that the prepared LED backlight module can meet the NTSC requirement of greater than 110%. Preferably, the ratio of the red quantum dots to the green quantum dots is 1:1-2:1, and the ratio can be adjusted according to actual needs.

[0051] The components of the quantum dot mixture include cadmium sulfide, cadmium selenide, cadmium telluride, zinc selenide, gallium nitride and / or indium arsenide, etc.

[0052] Furthermore, the accommodating cavity 12 is preferably a truncated cone, and the cross-sectional area of ​​the accommodating cavity 12 gradually increases from the blue light chip 2 toward the silicone rubber, so as to facilitate demoulding of the accommodating cavity 12 after injection molding.

[0053] Reference Figure 5 As shown, the blue light chip 2 used is a flip chip, and the blue light chip 2 includes an electrode 21 and a P-type GaN layer 22, an emission layer 23, an N-type GaN layer 24 and a substrate 25 arranged in sequence from bottom to top. The emission layer 23 is a multiple quantum well (MQWs).

[0054] The top of the electrode 21 abuts the P-type GaN layer 22, and the bottoms of both the P-type GaN layer 22 and the electrode 21 abut the bottom of the accommodating cavity 12. The bumps provided on the electrode 21 are connected to the bottom of the accommodating cavity 12, thereby shortening the heat conduction path between the electrode 21 and the substrate 11, improving the thermal conductivity of the blue light chip 2, and increasing the heating area of ​​the blue light chip 2, thereby improving the luminous performance of the blue light chip 2. Furthermore, the use of a flip-chip blue light chip 2 can reduce the amount of wire bonding between the bumps of the electrode 21 and the bottom of the accommodating cavity 12, thereby improving the production efficiency of the quantum dot LED lamp beads and reducing defects caused by wire bonding quality.

[0055] Furthermore, the preparation method of quantum dot LED lamp beads includes the following steps in sequence:

[0056] S1: placing the blue light chip 2 in the receiving cavity 12 on the substrate 1 .

[0057] S2: Coat the quantum dot mixture and silica gel on the base film from bottom to top.

[0058] The coating area of ​​the quantum dot mixture is greater than or equal to the area of ​​the blue light chip 2 , the silica gel covers the quantum dot mixture, the silica gel and the quantum dot mixture form quantum dot glue, and the quantum dot glue and the base film are combined into a quantum dot film 3 .

[0059] S3: After the base film is turned 180 degrees, the quantum dot glue is sent into the receiving cavity 12, the silica gel seals the receiving cavity 12, and the quantum dot mixture and the blue light chip 2 are arranged opposite to each other.

[0060] S4: The quantum dot glue is combined with the blue light chip 2 and the receiving cavity 12 respectively by vacuum hot pressing.

[0061] S5: After the quantum dot material and the silicone are solidified, the substrate 1 is cut to form a plurality of substrates 11 , each substrate 11 comprising a receiving cavity 12 , so as to form quantum dot LED lamp beads.

[0062] In summary, the preparation method of the quantum dot LED lamp beads is simple and has fewer steps, thereby improving the molding yield of the quantum dot LED lamp beads.

[0063] Specifically, the vacuum hot pressing method used in step S3 prevents bubbles from forming in the silica gel and quantum dot mixture during the preparation process, which could lead to light loss during the illumination of the quantum dot LED. Step S3 also includes: flushing the silica gel with the receiving cavity 12 to improve the reliability of the quantum dot LED. During this process, the silica gel can be applied once or multiple times until it is flush with the receiving cavity 12.

[0064] Step S4 also includes: using automatic cutting equipment to cut out quantum dot LED lamp beads to improve the preparation efficiency of quantum dot LED lamp beads.

[0065] In the description of this specification, the terms "one embodiment", "some embodiments", "embodiments", "examples", "specific examples" or "some examples" refer to the specific features, structures, materials or characteristics described in conjunction with the embodiment or example and included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification and features of different embodiments or examples, unless they are mutually inconsistent.

[0066] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may alter, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A method for preparing quantum dot LED lamp beads, characterized in that: The following steps are included in sequence: S1: placing the blue light chip (2) in the receiving cavity (12) on the substrate (1); S2: coating the quantum dot mixture and silica gel on the base film from bottom to top; The coating area of ​​the quantum dot mixture is greater than or equal to the area of ​​the blue light chip (2), so that the amount of the quantum dot mixture in each quantum dot LED lamp bead after molding corresponds to one blue light chip (2); the silica gel coats the quantum dot mixture, and the silica gel and the quantum dot mixture form a quantum dot glue; the quantum dot mixture includes red quantum dots and green quantum dots; S3: After the base film is turned 180 degrees, the quantum dot glue is introduced into the accommodating cavity (12), the silica gel seals the accommodating cavity (12), and covers the quantum dot mixture and the blue light chip (2), and the quantum dot mixture and the blue light chip (2) are arranged relative to each other; S4: combining the quantum dot glue with the blue light chip (2) and the accommodating cavity (12) respectively by vacuum hot pressing; S5: After the quantum dot mixture and the silica gel are solidified, cutting along the substrate (1) to form a plurality of base plates (11), each of the base plates (11) comprising one of the accommodating cavities (12), to form the quantum dot LED lamp beads.

2. The method for preparing a quantum dot LED lamp bead according to claim 1, wherein: The components of the quantum dot mixture include cadmium sulfide, cadmium selenide, cadmium telluride, zinc selenide, gallium nitride and / or indium arsenide.

3. The method for preparing a quantum dot LED lamp bead according to claim 1, wherein: The accommodating cavity (12) is a truncated cone, and the cross-sectional area of ​​the accommodating cavity (12) gradually increases in a direction from the blue light chip (2) toward the silica gel.

4. The method for preparing a quantum dot LED lamp bead according to claim 1, wherein: The blue light chip (2) is a flip chip, and the blue light chip (2) comprises an electrode (21) and a P-type GaN layer (22), an emission layer (23), an N-type GaN layer (24), and a substrate (25) arranged in sequence from bottom to top; The top of the electrode (21) abuts against the P-type GaN layer (22), the bottoms of the P-type GaN layer (22) and the electrode (21) abut against the bottom of the accommodating cavity (12), and the bump provided on the electrode (21) is connected to the bottom of the accommodating cavity (12).

5. The method for preparing a quantum dot LED lamp bead according to claim 1, wherein: Step S3 also includes: the silica gel is flush with the accommodating cavity (12).

6. The method for preparing a quantum dot LED lamp bead according to claim 1, wherein: Step S4 also includes: cutting the substrate (1) using automatic cutting equipment.

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