Quantum dot light-emitting element

Abstract

A quantum dot light-emitting element includes a base, a light-emitting unit, and a gas-barrier unit. The base includes a bottom plate and a reflector forming upwards from the bottom plate, the reflector and the bottom plate forming an accommodating space. The light-emitting unit is electrically connected to the bottom plate and located within the accommodating space, and includes a blue light-emitting layer, a red light-emitting layer, a first light-transmitting barrier layer, and a green light-emitting layer. The gas-barrier unit includes a first inorganic protective layer covering at least the surfaces of the light-emitting unit and the reflector opposite to the bottom plate, a first organic protective layer covering the surface of the first inorganic protective layer, and a second inorganic protective layer covering the surface of the first organic protective layer. Through the structural design of this gas-barrier unit, moisture can be effectively blocked from the outside, thereby protecting the light-emitting unit.

Description

[Technical Field]

[0001] This invention relates to a light-emitting element, and more particularly to a quantum dot light-emitting element. [Previous Technology]

[0002] In order to provide viewers with a better viewing experience, the images displayed on a monitor need to reproduce more realistic colors. Currently, to achieve more realistic colors, light-emitting diodes (LEDs) are usually used in conjunction with color filters. However, the emergence of quantum dot technology has further advanced the development of monitors.

[0003] Because quantum dots have a narrow emission spectrum and their color can be changed by adjusting their composition and particle size, the combination of quantum dots with different emission colors (such as quantum dots that can emit the three primary colors, red, green and blue) can make the display cover a wide range of colors and present high color saturation to meet the viewing experience.

[0004] However, quantum dots are often affected by external factors, which affect their luminescence efficiency. The most obvious effect is water vapor. Quantum dots will deteriorate and fail after contacting water vapor. Therefore, encapsulation materials such as silicone resin or glass layers are often used to block water vapor, but some water vapor will still contact the quantum dots through the gaps.

[0005] Therefore, how to more effectively prevent water vapor from contacting quantum dots in order to avoid affecting the performance of quantum dot display devices is the current focus of research in related technical fields. [Summary of the Invention]

[0006] Therefore, the object of the present invention is to provide a quantum dot light-emitting element with good gas barrier properties.

[0007] Thus, the quantum dot light-emitting element of the present invention includes a base, a light-emitting unit, and a gas-blocking unit.

[0008] The base includes a base plate and a reflector forming upward from the base plate, the reflector and the base plate together forming an accommodating space.

[0009] The light-emitting unit is electrically connected to the base plate and located in the accommodating space, including a blue light-emitting layer, a red light-emitting layer, a first light-transmitting barrier layer, and a green light-emitting layer stacked sequentially upward from the surface of the base plate.

[0010] The gas barrier unit includes a first inorganic protective layer, a first organic protective layer, and a second inorganic protective layer.

[0011] The first inorganic protective layer at least covers the surface of the light-emitting unit and the reflector opposite to the base plate.

[0012] The first organic protective layer covers the surface of the first inorganic protective layer opposite to the surface of the light-emitting unit.

[0013] The second inorganic protective layer covers the surface of the first organic protective layer opposite to the first inorganic protective layer.

[0014] The advantage of the present invention is that, by means of the stacked structure design of the first inorganic protective layer, the first organic protective layer and the second inorganic protective layer, the light-emitting unit is isolated from the outside world, so as to prevent water vapor from contacting the light-emitting unit.

Implementation Method

[0016] Before the present invention is described in detail, it should be noted that similar elements are represented by the same numbers in the following description.

[0017] The relevant technical content, features, and effects of the present invention will be clearly presented in the following detailed description of the embodiments with reference to the accompanying drawings. Furthermore, it should be noted that the drawings of the present invention are only for illustrating the structural and / or positional relationships between elements and are not related to the actual dimensions of each element.

[0018] Referring to Figure 1, an embodiment of the quantum dot light-emitting element of the present invention includes a base 2, a light-emitting unit 3, and a gas-blocking unit 4.

[0019] The base 2 includes a base plate 21 for encapsulation and a reflector 22 formed upward from the base plate 21. The reflector 22 is mainly used to encapsulate the light-emitting unit 3, and can also be used to reflect the light emitted from the light-emitting unit 3, and together with the base plate 21, they form an accommodating space.

[0020] The light-emitting unit 3 is disposed on the base plate 21 and located in the accommodating space, and is electrically connected to the base plate 21. It includes a blue light-emitting layer 31, a red light-emitting layer 32, a first light-transmitting barrier layer 33, a green light-emitting layer 34, and a second light-transmitting barrier layer 35, which are stacked sequentially upward from the surface of the base plate 21. Among them, the red light-emitting layer 32 and the green light-emitting layer 34 are made of materials that can absorb incident light and convert it into corresponding color light. For example, organic dyes, phosphors, quantum dots, and cadmium-free quantum dots can be used as light conversion materials, but are not limited thereto.

[0021] This embodiment uses a blue light-emitting layer 31 as a flip-chip packaged blue diode, a red light-emitting layer 32 with phosphors that absorb incident light and convert it into red light, and a green light-emitting layer 34 with quantum dots that absorb incident light and convert it into green light as an example. The related processes and material selection for the blue light-emitting diode, the phosphor, and the quantum dots are well known to those skilled in the art, and therefore will not be described in detail.

[0022] The first light-transmitting barrier layer 33 is made of a light-transmitting material and is formed on the surface of the red light-emitting layer 32. The green light-emitting layer 34 is formed on the first light-transmitting barrier layer 33. The first light-transmitting barrier layer 33 can protect the red light-emitting layer 32 and the blue light-emitting layer 31, and can prevent damage to the red light-emitting layer 32 when the green light-emitting layer 34 is formed, and can prevent the materials of the green light-emitting layer 34 and the red light-emitting layer 32 from contaminating each other.

[0023] The second light-transmitting barrier layer 35 is formed on the surface of the green light-emitting layer 34, which can further improve the effect of the quantum dot light-emitting element in blocking water vapor, and can protect the quantum dots of the green light-emitting layer 34, avoiding the problem of lattice mutation of the quantum dots due to high temperature when the gas barrier unit 4 is formed later.

[0024] The light-emitting unit 3 and the reflector 22 are formed by first connecting the blue light-emitting layer 31 to the conductive lines of the base plate 21 (not shown) using a chip-on-chip (COB) package to enable external electrical connection. Then, the reflector 22 is fixed to the base plate 21 and tightly attached to the blue light-emitting layer 31. Finally, the red light-emitting layer 32, the first light-transmitting barrier layer 33, the green light-emitting layer 34, and the second light-transmitting barrier layer 35 are sequentially formed in the accommodating space to complete the fabrication of the light-emitting unit 3 and the reflector 22.

[0025] In some embodiments, the light-emitting unit 3 may only have the first light-transmitting barrier layer 33, which can also achieve the effect of blocking gas and protection.

[0026] The gas barrier unit 4 includes a first inorganic protective layer 41, a first modified layer 42, a first organic protective layer 43, a second inorganic protective layer 44, and a second modified layer 45 formed in sequence.

[0027] Specifically, the first inorganic protective layer 41 completely covers the exposed surfaces of the light-emitting unit 3 and the reflector 22. The first modified layer 42 is formed on the surface of the first inorganic protective layer 41, and the first organic protective layer 43 is bonded to the first inorganic protective layer 41 through the first modified layer 42; the second inorganic protective layer 44 covers the surface of the first organic protective layer 43 opposite to the surface of the first inorganic protective layer 41, and the second modified layer 45 is formed on the surface of the second inorganic protective layer 44 opposite to the surface of the first inorganic protective layer 41.

[0028] The constituent materials of the first inorganic protective layer 41 and the second inorganic protective layer 44 may be selected from silicon nitride, silicon oxide and silicon oxynitride respectively, and the material of the first organic protective layer 43 may be selected from polyacrylate and polysiloxane, and may be formed by chemical vapor deposition (CVD), atomic layer deposition (ALD) and other methods.

[0029] The first modified layer 42 is formed by performing a hydrophilic plasma surface treatment on the first inorganic protective layer 41. By making the first modified layer 42 hydrophilic, it is beneficial to the adhesion between the subsequently formed first organic protective layer 43 and the surface of the first inorganic protective layer 41.

[0030] The second modified layer 45 is formed by performing a hydrophobic plasma surface treatment on the second inorganic protective layer 44. Making the second modified layer 45 hydrophobic can further enhance the effect of the gas barrier unit 4 in blocking water vapor.

[0031] The selection of materials for the aforementioned hydrophilic plasma modification and hydrophobic plasma modification is well known to those skilled in the art, and therefore will not be described further.

[0032] In some embodiments, the air-blocking unit 4 may also achieve the effect of blocking water vapor without forming the first modified layer 42 and / or the second modified layer 45 as needed.

[0033] In some embodiments, the gas barrier unit 4 may also cover only the surface of the light-emitting unit 3 and the reflector 22 opposite to the base plate 21 as needed, without extending to cover the outer surface of the reflector 22, and can still achieve the purpose of gas barrier protection.

[0034] In summary, the quantum dot light-emitting element of the present invention, by sequentially forming the first inorganic protective layer 41, the first organic protective layer 43, and the second inorganic protective layer 44, forms a composite gas barrier structure, which can effectively prevent water vapor from contacting the quantum dots of the light-emitting unit 3. Furthermore, the first modified layer 42 further enhances the adhesion between the first organic protective layer 43 and the first inorganic protective layer 41, and the second modified layer 45 provides hydrophobicity to the surface of the gas barrier unit 4, further effectively blocking water vapor and extending the overall lifespan of the element. Therefore, the objective of the present invention is indeed achieved.

[0035] However, the above description is only an embodiment of the present invention and should not be construed as limiting the scope of the present invention. Any simple equivalent changes and modifications made in accordance with the scope of the patent application and the contents of the patent specification of the present invention shall still fall within the scope of the patent of the present invention. [Simplified Explanation of the Diagram]

[0015] Other features and effects of the present invention will be clearly presented in the embodiments with reference to the figures, wherein: Figure 1 is a side cross-sectional view showing an embodiment of the quantum dot light-emitting element of the present invention.

Claims

1. A quantum dot light-emitting element, comprising: a base including a bottom plate and a reflector forming upward from the bottom plate, the reflector and the bottom plate forming an accommodating space; a light-emitting unit electrically connected to the bottom plate and located in the accommodating space, including a blue light-emitting layer, a red light-emitting layer, a first light-transmitting barrier layer, and a green light-emitting layer sequentially stacked upward from the surface of the bottom plate; and a gas-barrier unit including: a first inorganic protective layer covering at least the surfaces of the light-emitting unit and the reflector opposite to the bottom plate; a first organic protective layer covering the surface of the first inorganic protective layer opposite to the light-emitting unit; and a second inorganic protective layer covering the surface of the first organic protective layer opposite to the first inorganic protective layer, wherein... The gas barrier unit also includes a first modified layer located between the first inorganic protective layer and the first organic protective layer, and the first modified layer is hydrophilic.

2. The quantum dot light-emitting element as claimed in claim 1, wherein, The blue light-emitting layer is a flip-chip packaged blue light-emitting diode, the red light-emitting layer has phosphors that can absorb incident light and convert it into red light, and the green light-emitting layer has quantum dots that can absorb incident light and convert it into green light.

3. The quantum dot light-emitting element as claimed in claim 1, wherein, The gas barrier unit completely covers the exposed surfaces of the light-emitting unit and the reflector.

4. The quantum dot light-emitting element as claimed in claim 1, wherein, The materials of the first inorganic protective layer and the second inorganic protective layer are selected from any one of silicon nitride, silicon oxide, and silicon oxynitride.

5. The quantum dot light-emitting element as claimed in claim 1, wherein, The material of the first organic protective layer is selected from either polyacrylate or polysiloxane.

6. The quantum dot light-emitting element as claimed in claim 1, wherein, The gas barrier unit also includes a second modified layer located on the surface of the second inorganic protective layer opposite to the first organic protective layer, and the second modified layer is hydrophobic.

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