TWI828569B - Light-emitting device and manufacturing method thereof - Google Patents

Abstract

A light-emitting device includes a light-emitting element, a cover layer, a quantum dot material (QD material) and an adhesive layer. The cover layer includes a recess portion and has transparent inorganic material. The quantum dot material is filled into the recess portion and disposed on the light emitting element, the light emitting element is bonding to the cover layer and the adhesive layer by the adhesive layer . Therefore, the light-emitting device may prevent moisture and oxygen from damaging the quantum dot material by covering the cover layer and the light emitting element to effect the luminous efficiency of the quantum dot material.

Description

Light-emitting device and manufacturing method thereof

The present invention relates to a light-emitting device, and in particular, to a packaging structure of quantum dot material and a manufacturing method thereof.

Light-Emitting Diode (LED) has the characteristics of low power consumption, low heat generation, long operating life, impact resistance, small size, and fast response speed. Therefore, it is widely used in various fields that require the use of light-emitting elements. For example, vehicles, home appliances, and lighting fixtures, etc. Wavelength conversion material, such as phosphor, is a photoluminescent substance that can absorb the first light emitted by the LED and then emit a second light of a different spectrum. The wavelength conversion material covering the light emitting diode can be used as a structure of the light emitting device.

In recent years, as the public's requirements for display image quality continue to increase, the technology development of wide color gamut has become one of the most important technological developments in displays. Among them, the National Television System Committee of the United States , abbreviated as NTSC) provides a judgment standard for wide color gamut. Generally speaking, in displays, if phosphor is used, the NTSC is about 70~80%, and if quantum dot (QD) materials are used, the NTSC can be as high as 100%, which can better meet the needs of a wide color gamut.

As shown in Figure 1, it is a type of light-emitting device, the structure of a wafer scale package (CSP). The light-emitting device includes a light-emitting element 1, such as an LED. The bottom surface of the light-emitting element 1 is provided with electrodes. 2. Cover the surface of the light-emitting element 1 with a layer of encapsulant 3. The encapsulant 3 is generally silicone resin mixed with phosphor. In order to achieve higher NTSC, traditional phosphors are replaced with quantum dot materials. Because the properties of quantum dot materials are easily affected by water vapor and oxygen, and silicone resin is easily penetrated by water vapor and oxygen, the luminous efficiency of wafer-level packaging will decrease. For this reason, how to improve the packaging of quantum dot materials to effectively block water vapor and oxygen has become an urgent goal for the industry.

The main purpose of the present invention is to provide a light-emitting device and a manufacturing method thereof, which seal a quantum dot material (QD material) in a packaging structure composed of a light-emitting element and a covering layer with a recessed portion. The covering layer and the light-emitting element block water and oxygen from the quantum dot material, preventing the quantum dot material from being corroded by water vapor and oxygen and affecting the luminous efficiency.

In order to achieve the aforementioned object, an embodiment of the present invention provides a light-emitting device. The light-emitting device includes a light-emitting element, a covering layer, a quantum dot material and an adhesive layer. The covering layer has a recessed portion and contains light-transmitting inorganic material. The quantum dot material is filled into the recessed portion of the covering layer and placed on the light-emitting element. The light-emitting element is combined with the covering layer and the quantum dot material through the adhesive layer.

To achieve the aforementioned objects, another embodiment of the present invention is a method of manufacturing a light-emitting device. The manufacturing steps include: providing a light-transmissive inorganic block with a plane, forming a recessed portion on the plane of the light-transmissive inorganic block to form a covering layer, the covering layer having an upper surface surrounding the recessed portion; providing a quantum dot material, Fill the recessed part of the covering layer; provide a light-emitting element with a light-emitting surface, a bottom surface and a two side surface; provide an adhesive layer to bond the upper surface of the recessed part, the quantum dot material and the light-emitting surface; provide a reflective layer, Surround the cover layer and both sides of the light-emitting element.

300, 500, 700A, 700B, 800, 900: Light emitting device

110, 510, 810, 910: Covering layer

110’: Translucent inorganic block

111: Upper surface

112, 912: depression

113: Lower surface

114:Outer side

120, 520, 920: Quantum dot material

130, 730: Adhesive layer

130’: Adhesive

131’:Top surface

132’: Bottom surface

1. 140: Light-emitting element

141: Luminous surface

142: Bottom surface

144: First electrode and second electrode

150, 550: light reflective layer

150’:Light reflective glue

151’: Partial light reflective glue

2:Electrode

3: Packaging glue

731: Opaque adhesive layer

732: Translucent adhesive layer

812a: First depression

812b: Second depression

S: gap

W1: Width of the depression

W2: Width of light-emitting element

D, D1: gap

Figure 1 is a schematic diagram illustrating a conventional wafer level packaging structure.

Figures 2A to 2G are schematic diagrams illustrating the manufacturing method of the light-emitting device disclosed in one embodiment of the present invention.

Figure 3 is a cross-sectional view of a light-emitting device disclosed according to an embodiment of the present invention.

FIG. 4 is a partially enlarged schematic diagram of a light-emitting device disclosed according to an embodiment of the present invention.

Figure 5 is a schematic diagram showing a light-emitting device disclosed according to a comparative example of the present invention.

Figure 6 shows the luminous efficiency of the light-emitting device according to one embodiment of the present invention and the light-emitting device according to the comparative example under different test times.

Figure 7A is a schematic diagram showing a light-emitting device disclosed according to another embodiment of the present invention.

Figure 7B is a schematic diagram showing a light-emitting device disclosed according to another embodiment of the present invention.

FIG. 8 is a schematic diagram showing a light-emitting device disclosed according to another embodiment of the present invention.

FIG. 9 is a schematic diagram showing a light-emitting device disclosed according to another embodiment of the present invention.

The quantum dot chip package and its manufacturing method of the present invention will be described in detail below. It should be understood that the following description provides many different embodiments or examples for implementing different aspects of the present invention. The specific components and arrangements described below are only used to briefly describe the present invention and are not intended to limit the present invention.

Please refer to Figures 2A to 2G, which are schematic diagrams of a manufacturing method of a light-emitting device according to an embodiment of the present invention. As shown in the figures, the manufacturing steps of this embodiment include:

Step 1: Referring to Figure 2A, a light-transmissive inorganic block 110' is provided with a flat surface 111'. In one embodiment, the material of the light-transmitting inorganic block 110' can be selected from glass.

Step 2: Refer to Figure 2B, remove part of the light-transmitting inorganic block 110' from an appropriate position on the plane 111' of the light-transmitting inorganic block 110' to form a recess 112 and form the covering layer 110. The covering layer 110 includes an upper surface 111 , a lower surface 113 and an outer surface 114 located between the upper surface 111 and the lower surface 113 . According to an embodiment, a method of forming the recessed portion 112 includes wet etching or dry etching, and dry etching is, for example, laser. In another embodiment, the covering layer 110 may be formed by molding the light-transmitting inorganic material through a mold.

Step 3. Referring to Figure 2C, a quantum dot material (QD material; Quantum Dot material) 120 is provided and filled into the recessed portion 112 of the covering layer 110. In this embodiment, the depth of the recessed portion 112 must be greater than or approximately equal to The thickness of quantum dot material 120. In one embodiment, the quantum dot material 120 includes a bonding agent (not shown) and quantum dot particles (not shown) dispersed in the bonding agent, and is applied by spraying or dispensing. A mask is selectively used to fill in the recessed portion 112 .

Step 4: Referring to Figure 2D, an adhesive 130' is provided and formed on the covering layer 110 and the quantum dot material 120. In one embodiment, the adhesive 130' is formed on the cover layer 110 and the quantum dot material 120 by dispensing. In one embodiment, the adhesive 130' has a top surface 131' and a bottom surface 132', and the bottom surface 132' of the adhesive 130' is bonded to the upper surface 111 of the covering layer 110 and the quantum dot material 120. The adhesive 130' preferably has the properties of heat resistance and high light transmittance. In one embodiment, the material of the adhesive 130' can be a thermosetting resin or a photo-curing resin, such as silicone resin.

Step 5: Referring to Figure 2E, a light-emitting element 140 is provided, which has a light-emitting surface 141, a bottom surface 142 and a two-side surface 143. And the light-emitting surface 141 of the light-emitting element 140 is attached to the top surface 131' of the adhesive 130', so that the light-emitting element 140 is combined with the covering layer 110 and the quantum dot material 120. (bonding) together. Afterwards, the adhesive 130' is cured to form the adhesive layer 130. The bottom surface 142 of the light-emitting element 140 is provided with a first electrode and a second electrode 144 that are electrically connected to the substrate (not shown).

Step 6: Refer to Figure 2F, provide a light reflective glue 150', and cover the cover layer 110, the adhesive layer 130 and the light emitting element 140 with the light reflective glue 150'. In one embodiment, the light reflective glue 150' covers the outer side 114 of the cover layer 110 and the two side surfaces 143 of the light emitting element. Afterwards, the light reflective glue 150' is cured and part of the light reflective glue 151' is removed to form a light reflective layer. In one embodiment, part of the light reflective glue 151' can be removed by grinding or deflashing. The light reflective layer surrounds the cover layer 110 , the adhesive layer 130 , the light-emitting element 140 and the side surfaces of the first electrode and the second electrode 144 of the light-emitting element 140 and exposes the upper surface of the electrode 144 .

In another embodiment, referring to Figure 2G, the light-reflective glue is accurately covered on the cover layer 110, the adhesive layer 130 and the sidewalls of the light-emitting element 140, and the light-reflective glue is cured to form the light-reflective layer 150 and the light-emitting device. In this embodiment, the bottom surface 142 of the light-emitting element 140 is not covered by the light reflective layer 150 .

Figure 3 is a cross-sectional view of the light emitting device 300 disclosed in Figures 2A to 2G of the present invention. FIG. 4 is a partially enlarged schematic diagram of the light emitting device 300 . The light-emitting device 300 includes a covering layer 110, a quantum dot material 120, an adhesive layer 130, a light-emitting element 140 and a light reflective layer 150. In one embodiment, the covering layer 110 has a recessed portion 112 and an outer surface 114 located between the upper surface 111 and the lower surface, and the quantum dot material 120 is filled in the recessed portion 112 . In one embodiment, the recessed portion 112 of the covering layer 110 has a width W1, the light-emitting element 140 has a width W2, and the width W2 of the light-emitting element 140 is greater than the width W1 of the recessed portion 112. In this way, the path for external water vapor and oxygen to contact the quantum dot material 120 can be increased or the opportunity for external water vapor and oxygen to contact the quantum dots can be increased to improve the efficiency of the quantum dots. Material 120 reliability. One side (the first side) of the adhesive layer 130 is bonded to the surface of the cover layer 110 and the surface of the quantum dot material 120 , and the other side (the second side) of the adhesive layer 130 is bonded to the light-emitting element 140 . In other words, the adhesive layer 130 directly contacts the cover layer 110, the quantum dot material 120 and the light emitting element 140. In one embodiment, the other side of the adhesive layer 130 is also adhered to the surface of the light reflective layer 150 . Since the quantum dot material 120 and the covering layer 110 of the present invention are disposed on the light-emitting element 140 through the adhesive layer 130, gaps will occur between the quantum dot material 120 and the light-emitting element 140 and between the covering layer 110 and the light-emitting element 140. In one embodiment, the gap D between the quantum dot material 120 and the light-emitting element 140 and the gap D1 between the covering layer 110 and the light-emitting element 140 must be as small as possible to prevent external water vapor and oxygen from penetrating the gaps D and D1 Penetration causes the luminous efficiency of the quantum dot material 120 to decrease. In one embodiment, the gaps D and D1 are less than 20 microns. In other words, the thickness of the adhesive layer 130 is less than 20 microns.

In one embodiment, the material of the covering layer 110 is composed of light-transmitting inorganic materials, such as glass and ceramics. The quantum dot material 120 includes a binding agent (not shown) and quantum dot particles (not shown) dispersed in the binding agent. The material of the bonding agent may be thermosetting resin or light-curing resin, such as epoxy resin or silicone resin. The material of the quantum dot particles can be composed of semiconductor materials, and the particle size is less than 100 nanometers (nm). The semiconductor material includes a II-VI semiconductor compound, a III-V semiconductor compound, a IV-VI semiconductor compound, or a combination of the above materials. The structure of the quantum dot particles may include a core that mainly emits light and a shell that covers the core. The material of the core area can be selected from zinc sulfide (ZnS), zinc selenide (ZnSe), zinc telluride (ZnTe), zinc oxide (ZnO), cesium lead chloride (CsPbCl ₃ ), cesium lead bromide (CsPbBr) ₃ ), cesium lead iodide (CsPbI ₃ ), cadmium sulfide (CdS), cadmium selenide (CdSe), cadmium telluride (CdTe), gallium nitride (GaN), gallium phosphide (GaP), gallium selenide ( GaSe), gallium antimonide (GaSb), gallium arsenide (GaAs), aluminum nitride (AlN), aluminum phosphide (AlP), aluminum arsenide (AlAs), indium phosphide (InP), indium arsenide (InAs) ), tellurium (Te), lead sulfide (PbS), indium antimonide (InSb), lead telluride (PbTe), lead selenide (PbSe), antimony telluride (SbTe), zinc cadmium selenide (ZnCdSe), sulfide A group consisting of zinc cadmium selenide (ZnCdSeS) and copper indium sulfide (CuInS). The material of the shell and the material of the core region must match each other (for example, the lattice constants of the materials of the core region and the shell need to match). Specifically, the selection of the material composition of the shell, in addition to matching the lattice constant of the material in the core region, can also form a high energy barrier region on the periphery of the core region to increase the quantum yield. The structure of the shell can be a single layer, multiple layers or a structure with a gradient in material composition. In one embodiment, the core region is cadmium selenide and the shell is a single layer of zinc sulfide. In another embodiment, the core region is cadmium selenide, and the shell includes an inner layer of (cadmium, zinc) (sulfur, selenium) and an outer layer of zinc sulfide. In another embodiment, the core region is cadmium selenide, the shell includes an inner layer of cadmium sulfide, a middle gradient layer of Zn _0.25 Cd _0.75 S/Zn _0.5 Cd _0.5 S/Zn _0.75 Cd _0.25 S, and an outer layer of zinc sulfide.

Referring to FIG. 3 , in the light-emitting device 300 , the light-emitting element 140 has a light-emitting surface 141 , a bottom surface 142 and a side surface 143 . The bottom surface 142 of the light-emitting element 140 is provided with a first electrode 144 and a second electrode 144 . The light reflective layer 150 covers the outer side surface 114 of the covering layer 110 and the side surface 143 of the light emitting element 140 . In one embodiment, the light reflective layer 150 surrounds the cover layer 110 and the light emitting element 140 .

In one embodiment, the light-emitting element 140 includes a carrier substrate (not shown), a light-emitting stack (not shown), a first electrode and a second electrode 144. In one embodiment, the carrier substrate is a growth substrate, such as a sapphire substrate, used as a substrate for epitaxial growth of the light-emitting stacked layer. In another embodiment, the carrier substrate is not the growth substrate, and the growth substrate is removed and replaced with other substrates (eg, substrates of different materials, different structures, or different shapes) during the process of manufacturing the first light-emitting element. In one embodiment, in order to reduce the heat transfer from the light-emitting element 140 to the quantum dot material 120, the carrier substrate is made of a material with a lower thermal conductivity, such as glass or ceramics with a lower thermal conductivity. A ceramic material with a lower thermal conductivity could be zirconia. In another embodiment, in order to more effectively dissipate the heat of the quantum dot material 120 through the light-emitting element 140, the carrier substrate has a higher thermal conductivity. It is composed of materials with high thermal conductivity, such as ceramics with high thermal conductivity. Ceramic materials with higher thermal conductivity can be aluminum oxide or aluminum nitride. Although not shown, the light-emitting stack includes several semiconductor layers. For example, the light-emitting stack includes a first-type semiconductor layer, a light-emitting layer, and a second-type semiconductor layer in sequence, wherein the light-emitting layer is disposed between the first-type semiconductor layer and the second-type semiconductor layer. The first-type semiconductor layer is, for example, an N-type semiconductor layer, and the second-type semiconductor layer is a P-type semiconductor layer. Alternatively, the first-type semiconductor layer is a P-type semiconductor layer, and the second-type semiconductor layer is an N-type semiconductor layer. In one embodiment, the first electrode and the second electrode 144 are located on the same side of the light-emitting element 140 and serve as an interface for electrical connection between the light-emitting element 140 and the outside world. The composition of the light reflective layer 150 includes resin and reflective particles dispersed in the resin, such as titanium oxide, zinc oxide, aluminum oxide, barium sulfate or calcium carbonate. In one embodiment, the resin is silicone resin and the reflective particles are titanium oxide.

The main technical means of the light-emitting device 300 of the present invention is to fill the recessed portion 112 of the covering layer 110 with the quantum dot material 120, and cover the quantum dot material 120 with the recessed portion 112, and the covering layer 110 is directly combined with the light-emitting element 140. (bonding) together, there is no material of the covering layer 110 between the covering layer 110 and the quantum dot material 120 and the light-emitting surface 141 of the light-emitting element 140, and the quantum dot material 120 is surrounded by the covering layer 110 and the light-emitting element 140. Accordingly, water vapor and oxygen are blocked by the covering layer 110 and the light-emitting element 140 . When external water vapor and oxygen want to contact the quantum dot material 120, they must first pass through the covering layer 110 and the light-emitting element 140. Since the width of the light-emitting element 140 is greater than the width of the recessed portion 112 of the covering layer 110, the recessed portion 112 is completely blocked. , thus preventing external water vapor and oxygen from directly eroding the quantum dot material 120 without being blocked by the light-emitting element 140 . In other words, the light-emitting device of the present invention has high resistance to water vapor and oxygen, which can improve the decrease in luminous efficiency of the quantum dot material 120.

Figure 5 is a cross-sectional view of the light-emitting device 500 disclosed according to the comparative example. The light-emitting device 500 includes a covering layer 510, a quantum dot material 520, an adhesive layer 130, a light-emitting element 140 and a light reflective layer 550. The biggest difference from the light-emitting device 300 disclosed in FIGS. 2A to 2G is that the width of the light-emitting element 140 is smaller than the width of the recessed portion 112 .

Figure 6 shows the relative luminous efficiency of the light-emitting device 300 (curve 1) of Figures 2A to 2G of the present invention (hereinafter referred to as the experimental example) and the light-emitting device 500 (curve 2) of the comparative example under different test times. The efficiency when the light-emitting device first starts emitting light (0 hours) is set as the relative luminous efficiency of 100%. In the experimental examples and comparative examples, the gap D between the quantum dot material and the light-emitting element, and the gap D1 between the covering layer and the light-emitting element are both less than 20 microns. The operating conditions are room temperature (25°C) and the operating current is 20 milliamps (mA).

Figure 6 shows that the relative luminous efficiency of the light-emitting device 300 in the experimental example can still reach 125% after a 480-hour (HRS) time test. The data shows that the light-emitting device 300 of the present invention uses quantum dots. The material 120 is filled into the recessed portion 112 of the covering layer 110 and is directly bonded with the light-emitting element 140. The covering layer 110 and the light-emitting element 140 block water vapor and oxygen, thereby delaying the luminous efficiency of the quantum dot material 120. Decreased efficacy.

Referring again to Figure 6, looking back at the data of the light-emitting device 500 of the comparative example, the luminous efficiency dropped greatly after 400 hours, and the luminous performance dropped from a relative luminous efficiency of 100% to a relative luminous efficiency of about 50%. It is confirmed that the light-emitting device 300 of the present invention has a significant effect in delaying the decrease in the luminous efficiency of the quantum dot material 120 when the width of the light-emitting element 140 is larger than the width of the recessed portion 112 .

Figure 7A is a schematic diagram showing a light emitting device 700A disclosed according to another embodiment of the present invention. As shown in the figure, the light-emitting device 700 includes a covering layer 110, a quantum dot material 120, an adhesive layer 730, a light-emitting element 140 and a light reflective layer 150. Compared with the light-emitting device 300, the adhesive layer 730 includes an opaque adhesive layer 731 and a light-transmitting adhesive layer 732. The opaque adhesive layer 731 is adhered to the joint surface of the cover layer 110 and the light-emitting element 140 , but is not adhered to the quantum dot material 120 . The opaque adhesive layer 731 combines the surface of the covering layer 110 and the surface of the light-emitting element 140, and the quantum dot material 120 is covered by the covering layer 110 and the light-emitting element 140. In this embodiment, the material of the opaque adhesive layer 731 can be metal or alloy. The metal is, for example, gold (Au), and the alloy is, for example, tin-silver-copper alloy (SAC alloy) or gold-tin alloy (Au-Sn alloy). In this embodiment, at least one opaque adhesive layer 731 is provided on the joint surface of the cover layer 110 and the light-emitting element 140 . In one embodiment, the light-emitting element 140 is a blue light-emitting diode. The blue light emitted by the light-emitting element 140 is blocked by the opaque adhesive layer 731 and does not penetrate laterally through the cover layer 110 , thus causing the upper part of the light-emitting device 700 and the Lateral light color unevenness. In addition, since the opaque adhesive layer 731 is a metal material, higher airtightness can be achieved when the covering layer 110 is combined with the light-emitting element 140, which can improve the resistance of the covering layer 110 and the light-emitting element 140 to external moisture and moisture. Oxygen barrier effect. The light-transmitting adhesive layer 732 is surrounded by the light-impermeable adhesive layer 731 . The light-transmitting adhesive layer 732 can adhere the quantum dot material 120 and the light-emitting element 140 and can be penetrated by the light emitted by the light-emitting element 140 . The material of the light-transmitting adhesive layer 732 may be the same as or similar to the material of the adhesive layer 130 . Figure 7B is a schematic diagram showing a light emitting device 700B disclosed according to another embodiment of the present invention. The difference from the light-emitting device 700A is that there is no light-transmitting adhesive layer 732 between the quantum dot material 120 and the light-emitting element 140 . In other words, the quantum dot material 120 and the light emitting element 140 may be in direct contact. Since the light absorption caused by the light-transmitting adhesive layer 732 is reduced, the brightness of the light-emitting device 700B can be improved.

FIG. 8 is a schematic diagram of a light-emitting device 800 disclosed according to another embodiment of the present invention. As shown in the figure, the light-emitting device 800 includes a covering layer 810, a quantum dot material 120, an adhesive layer 130, a light-emitting element 140 and a light reflective layer 150. Compared with the light emitting device 300, the covering layer 810 has a first recessed portion 812a and a second recessed portion 812b, and the width of the first recessed portion 812a is smaller than the width of the second recessed portion 812b. In one embodiment, the first recessed portion 812a and the second recessed portion are connected with each other and are stepped. In one embodiment, the quantum dot material 120 and the light-emitting element 140 are filled into the first recessed portion 812a and the second recessed portion 812b respectively, and then the covering layer 810 and the light-emitting element 140 are combined, so that the quantum dot material 120 is sealed. between the covering layer 810 and the light-emitting element 140. As shown in Figure 8, the quantum dot material 120 and the light-emitting element 140 are completely filled in the first recessed portion 812a and the second recessed portion 812b of the covering layer 810, and the bottom surface 142 of the light-emitting element 140 and the lower surface of the covering layer 810 The surfaces 813 are substantially aligned, so when the light-emitting element 140 is combined with the cover layer 810, the quantum dot material 120 is attached to the light-emitting element 140. In addition, in this embodiment, the lowermost surface of the covering layer 810 is not above the light-emitting element 140, so there is no gap problem between the quantum dot material 120 and the light-emitting element 140 and between the covering layer 810 and the light-emitting element 140. . Therefore, in this embodiment, when external water vapor and oxygen want to contact the quantum dot material 120, they must first pass through the covering layer 810 and the light-emitting element 140, and because the width of the light-emitting element 140 is larger than the first width of the covering layer 810, The width of the recessed portion 812a completely blocks the first recessed portion 812a. In addition, there is no gap between the quantum dot material 120 and the light-emitting element 140, which can better block the penetration of external water vapor and oxygen, thus delaying the quantum dot material. 120 The effect of reduced luminous efficiency. The material and manufacturing method of the covering layer 810 are the same as or similar to those of the covering layer 110 . Please refer to the relevant paragraphs describing the covering layer 110 .

FIG. 9 is a schematic diagram showing a light emitting device 900 disclosed according to another embodiment of the present invention. As shown in the figure, the light-emitting device 900 includes a covering layer 910, a quantum dot material 920, and a light-emitting element 140. and light reflective layer 150. The covering layer 910 has a recessed portion 912. The inner surface of the recessed portion 912 has a slope and the depth must be greater than or approximately equal to the thickness of the quantum dot material 120 plus all or part of the height of the light-emitting element 140, so that the quantum dot material 120 is in contact with the light-emitting element 140. can be placed in the recessed portion 912 at the same time. When the covering layer 910 and the light-emitting element 140 are combined, the quantum dot material 920 can be covered by the covering layer 910 and the light-emitting element 140. As shown in Figure 9, when the quantum dot material 920 and the light-emitting element 140 are installed in the recessed portion 912 of the covering layer 910, the bottom surface 142 of the light-emitting element 140 protrudes from the lower surface 911 of the covering layer 910, and the recessed portion 912 has a gap S with the side of the light-emitting element 140 due to the slope formed on both sides. When the light reflective layer 150 covers both sides of the cover layer 910 and the light-emitting element 140 and fills the gap S at the same time, it can further prevent water vapor and oxygen from penetrating into the light-emitting device 900 and causing the quantum dot material 920 to deteriorate. In this embodiment, when the light-emitting element 140 is combined with the covering layer 910, the quantum dot material 920 is in close contact with the light-emitting element 140, and because the lowermost surface of the covering layer 910 is not located above the light-emitting element 140, It can avoid the problem of the penetration of external water vapor and oxygen caused by the gap between the quantum dot material 120 and the light-emitting element 140 . In the light-emitting device 900, the relationship between the width of the recessed portion 912 of the covering layer 910 and the width of the light-emitting element 140 can be adjusted more flexibly. The two can be equal or unequal.

In summary, the light-emitting device of the present invention uses quantum dot on chip (QD on chip) technology. The quantum dot material is filled into the recessed part of the covering layer and placed on the light-emitting element. The light-emitting element is directly combined with the covering layer, and the width of the light-emitting element is larger than the aperture of the recessed part of the packaging glass to completely block the recessed part to avoid external water and oxygen. Or the oxygen directly erodes the quantum dot material without being blocked by the light-emitting element. In other words, the light-emitting device of the present invention uses a covering layer and a light-emitting element with high water and oxygen barrier properties to block the quantum dot material from being damaged by water vapor and oxygen, thereby delaying the decline in the luminous efficiency of the quantum dot material.

Although the present invention is disclosed above in various embodiments, these are only examples and are not used to limit the scope of the present invention. Anyone skilled in the art can make some modifications without departing from the spirit and scope of the present invention. Changes and embellishments. Therefore, the above embodiments are not intended to limit the scope of the present invention. The protection scope of the present invention shall be determined by the appended patent application scope.

300:Lighting device

110: Covering layer

120:Quantum dot materials

130:Adhesive layer

140:Light-emitting component

150:Light reflective layer

111: Upper surface

112: depression

113: Lower surface

114:Outer side

141: Luminous surface

142: Bottom surface

143:Side surface

144: First electrode and second electrode

W1: Width of the depression

W2: Width of light-emitting element

D: Gap

D1: Gap

Claims (10)

A light-emitting device, including: a light-emitting element including a first side surface and a first width; a quantum dot material disposed on the light-emitting element and including a first lower surface, a first upper surface, a first a second side surface, and a second width, wherein the second width is greater than the first width; and a covering layer covering the first upper surface and the second side surface of the quantum dot material and including a second Lower surface; wherein, the first lower surface and the second lower surface are coplanar and not lower than the light-emitting element. For example, in the light-emitting device of claim 1, the covering layer includes a third width, and the third width is greater than the second width. For example, in the light-emitting device of Item 1 of the patent application, the quantum dot material does not cover the first side surface. For example, in the light-emitting device of claim 1, the covering layer does not cover the first side surface. For example, the light-emitting device of Item 1 of the patent application further includes an adhesive layer, and the adhesive layer is located between the light-emitting element and the quantum dot material. For example, in the light-emitting device of Item 5 of the patent application, the quantum dot material is located in the space formed by the covering layer and the adhesive layer. For example, the light-emitting device of Item 1 of the patent application further includes a light-reflective layer, and the light-reflective layer surrounds the light-emitting element. For example, in the light-emitting device of claim 1, the covering layer includes a third side surface, and the third side surface is parallel to the second side surface. For example, in the light-emitting device of claim 1, the covering layer includes a second upper surface, and the second upper surface is parallel to the first upper surface. For example, in the light-emitting device of claim 1 of the patent application, in a view, the first lower surface includes a portion that does not overlap with the light-emitting element.

Images