TW201911607A - Light emitting device and method of manufacturing same - Google Patents

Abstract

A light-emitting device includes a light-emitting element, a wavelength conversion layer and a reflective wall. The light-emitting element has a first top surface, a bottom surface and a lateral surface arranged between the first top surface and the bottom surface. The wavelength conversion layer has a wavelength conversion material and includes a second top surface covering the first top surface. The reflective wall surrounds the lateral surface of the light-emitting element, and directly contacts the wavelength conversion layer. A step is formed between the reflective wall and the second top surface. The light-emitting device has a light angle of 110 DEG to 118 DEG.

Description

Light emitting device and manufacturing method thereof

The present invention relates to a light-emitting device and a method for manufacturing the same, and more particularly, to a light-emitting device including a wavelength conversion layer and a reflection fence and a method for manufacturing the same.

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, so it is widely used in various fields that require the use of light-emitting elements. For example, vehicles, home appliances, and lighting fixtures.

LED is a kind of monochromatic light. If it is to be a white light emitting device, it is necessary to mix other colors of light. There are several ways to mix other colors of light. For example, a wavelength conversion layer such as a phosphor layer can be covered on the LED to achieve this purpose. Phosphor is a kind of photoluminescence substance. It can absorb the first light emitted by the LED and emit a second light with a different spectrum. When the first light is not completely consumed, the first light and the second light that are not consumed are mixed with each other to form a mixed light of another color, for example, white light.

LED white light emitting devices have different requirements for the light emitting angle in different applications, but the light emitting angle of general LED white light emitting devices may not necessarily meet the required application.

The invention discloses a light-emitting device including a light-emitting element, a wavelength conversion layer and a reflection fence. The light emitting element includes an upper surface, a lower surface, and a side surface between the upper surface and the lower surface. The wavelength conversion layer includes a wavelength conversion material and includes a second upper surface covering the first upper surface. The reflection fence surrounds the side of the light emitting element, and directly contacts the wavelength conversion layer, and there is a gap between the reflection fence and the second upper surface. The light emitting device has a light emitting angle between 110 degrees and 118 degrees.

The invention discloses a method for forming a light emitting device. A plurality of light emitting elements are formed on a carrier board. A light-emitting element is covered with a wavelength conversion film. A portion of the wavelength conversion film is removed to form a plurality of wavelength conversion layers. A reflective layer is covered over the wavelength conversion layers. A part of the reflective layer is removed to form a reflective frame and the wavelength conversion layers are exposed. At least one wavelength conversion layer forms a gap with the reflective frame. The reflecting frame is separated to form a plurality of reflecting fences.

FIG. 1A is a cross-sectional view of a light emitting device 100 according to an embodiment of the invention. The light-emitting device 100 includes a light-emitting element 120, a wavelength conversion layer 140, and a reflection fence 160. In this embodiment, the light emitting device 100 further includes a reflective layer 150 (first reflective layer) and a conductive portion 180. In another embodiment, the light emitting device 100 does not include the reflective layer 150 and the conductive portion 180. The wavelength conversion layer 140 covers a part of the surface of the light emitting element 120. In addition, a reflection fence 160 surrounds the wavelength conversion layer 140. Specifically, referring to FIG. 1B, the reflection fence 160 surrounds the light emitting element 120 and the wavelength conversion layer 140 at the same time. Referring to FIG. 1A, the light emitting device 100 includes a top surface 102, a bottom surface 104, and a plurality of side surfaces 106. The side surfaces 106 are located between the top surface 102 and the bottom surface 104.

In one embodiment, the light-emitting element 120 includes a carrier substrate 122, a light-emitting layer 124, and a contact electrode 126. One side of the light-emitting layer 124 faces the carrier substrate 122 and the other side faces the contact electrode 126. In addition, the light emitting element 120 includes an upper surface 121, a lower surface 123, and a plurality of side surfaces 125. The side surfaces 125 are located between the top surface 121 and the bottom surface 123. The carrier substrate 122 can be used to carry or support the light emitting layer 124. In addition, light emitted from the light emitting layer 124 can pass through the carrier substrate 122. Furthermore, the side of the carrier substrate 122 far from the light-emitting layer 124 is also the upper surface 121 of the light-emitting element 120, that is, the light-emitting surface of the light-emitting element 120. In one embodiment, the carrier substrate 122 is a growth substrate. For example, the carrier substrate 122 may be a sapphire substrate as a substrate when the light emitting layer 124 is epitaxially grown. In another embodiment, the carrier substrate 122 is not a growth substrate, and the growth substrate is removed or replaced with other substrates (for example, substrates of different materials, different structures, or different shapes) during the manufacturing process of the light-emitting device 100.

In one embodiment, the light emitting layer 124 includes a first semiconductor layer, an activation layer, and a second semiconductor layer (not shown). The first semiconductor layer may be an n-type semiconductor layer, and the second semiconductor layer may be a p-type semiconductor layer. In one embodiment, the contact electrode 126 includes two contact electrodes 126a and 126b located on the same side of the light emitting element 120 as an interface for electrically connecting the light emitting element 120 to the outside. The lower surface 123 includes the surfaces of the two contact electrodes 126a and 126b. Therefore, in FIG. 1A, the lower surface 123 refers to a part of the bottom surface of the light emitting layer 124 and the surfaces of the contact electrodes 126a and 126b. The contact electrodes 126a and 126b are electrically connected to the first semiconductor layer and the second semiconductor layer, respectively. In addition, the contact electrodes 126a and 126b may protrude (below) the bottom surface of the wavelength conversion layer 140 (as shown in the figure), be approximately flush with the bottom surface (not shown), or only one of them protrudes from the bottom surface (not shown) ). The side surface 125 includes a side surface of the carrier substrate 122 and the light emitting layer 124. The side surface 125 may also be a light emitting surface of the light emitting element 120. In one embodiment, the light-emitting element 120 has four side surfaces 125, and the opposite side surfaces 125 are substantially parallel to each other, that is, the light-emitting element 120 is square, rectangular, or parallelogram as viewed from a top view. A portion of the upper surface 121 and the lower surface 123 is also substantially parallel to each other. In one embodiment, the light-emitting element 120 is a flip chip LED die.

The light emitting element 120 may be a light emitting diode die (LED die), such as but not limited to a blue light emitting diode die or an ultraviolet (UV) light emitting diode die. In one embodiment, the light-emitting element 120 is a blue light-emitting diode die, and can provide a first light through a power source, and the first light has a dominant wavelength or a peak wavelength of 430. nm to 490 nm. In another embodiment, the light-emitting element 120 is a violet light-emitting diode crystal grain, and the dominant wavelength or peak wavelength of the first light is between 400 nm and 430 nm. In another embodiment, the light-emitting element 120 is an ultraviolet light-emitting diode grain, and the peak wavelength of the first light is between 315 nm and 400 nm or between 280 nm and 315 nm. .

The wavelength conversion layer 140 may include an adhesive 142 and a plurality of wavelength conversion particles 144 dispersed in the adhesive 142, wherein the wavelength conversion particles 144 can absorb the first light emitted by the light emitting element 120 and convert part or all of the first light into The first light has a second light having a different wavelength or spectrum. The color emitted by the second light is, for example, green light, yellow-green light, yellow light, amber light, orange-red light, or red light. In one embodiment, the second light which is excited by the wavelength conversion particles 144 after absorbing the first light (for example, blue light or UV light) is yellow light, and its main wavelength or peak wavelength is between 530 nm and 590 nm. In another embodiment, the second light which is excited by the wavelength conversion particles 144 after absorbing the first light (for example, blue light or UV light) is green light, and its main wavelength or peak wavelength is between 515 nm and 575 nm. In other embodiments, the second light which is excited by the wavelength conversion particles 144 after absorbing the first light (for example, blue light or UV light) is red light, and its main wavelength or peak wavelength is between 600 nm and 660 nm.

The wavelength conversion layer 140 may include a single type or a plurality of wavelength conversion particles 144. In one embodiment, the wavelength conversion layer 140 includes a single type or a plurality of wavelength conversion particles that emit yellow light. In another embodiment, the wavelength conversion layer 140 includes a plurality of wavelength conversion particles that can emit green light and red light. In this way, in addition to the second light that emits green light, it also includes the third light that emits red light, and can produce a mixed light with the first light that is not absorbed. In another embodiment, the first light is completely or almost completely absorbed by the wavelength conversion particles in the wavelength conversion layer 140. In this context, "almost completely" means that the intensity of light at the peak wavelength of the first ray in the mixed light is less than or equal to 3% of the intensity of the peak wavelength of the second ray and / or the third ray. The wavelength conversion layer 140 may also be composed of a multilayer structure (not shown). In one embodiment, the wavelength conversion layer 140 includes a layer containing wavelength conversion particles 144 and another layer of light diffusion (not shown). The wavelength conversion layer 140 including a plurality of wavelength conversion particles may have a single-layer structure or a multilayer structure. The single-layer structure means that a plurality of wavelength conversion particles are uniformly or unevenly distributed in a single layer. The multilayer structure means that a single type of wavelength conversion particle is generally distributed only in a single layer, and different types of wavelength conversion particles have a more clearly distinguishable interface. In one embodiment, the wavelength conversion layer 140 includes a short wavelength wavelength conversion layer and a long wavelength wavelength conversion layer. The short-wavelength wavelength conversion layer herein refers to wavelength conversion particles containing relatively short emission peaks, for example, the peaks are between 510 nm and 590 nm. The long wavelength wavelength conversion layer refers to wavelength conversion particles containing relatively long emission peaks, for example, the peaks are between 600 nm and 660 nm. In one embodiment, the long wavelength conversion layer is closer to the light emitting element 120 than the short wavelength conversion layer.

The adhesive 142 can disperse the wavelength conversion particles 144 in space, and can fix the relative positions of the wavelength conversion particles 144 to each other. In general, the higher the concentration (or weight percentage) of the wavelength conversion particles 144, the more light from the light emitting element 100 can be converted into another light (the higher the conversion ratio). However, if the concentration of the wavelength conversion particles 144 is too high, it means that the content of the adhesive 142 is too small, and the wavelength conversion particles 144 may not be effectively fixed. In one embodiment, the weight percentage of the wavelength conversion particles 144 in the wavelength conversion layer 140 is less than 70%. In another embodiment, the weight percentage of the wavelength conversion particles 144 in the wavelength conversion layer 140 is 20% to 60%. The wavelength conversion particles 144 can obtain better conversion ratio and scattering effect in the above-mentioned weight percentage range, and can be effectively fixed in position in space. In an embodiment, the light emitted through the light emitting element 100 is mixed with another light converted by the wavelength conversion particles 144 to produce white light. The color temperature of the white light in the light emitting device 100 can be transmitted through the light emitted by the light emitting element 100 and the wavelength conversion particles. Adjust the proportion of the other light emitted by 144. In one embodiment, the color temperature of the light-emitting device 100 is between 1900K and 6000K. In addition, in order for the first light that excites the wavelength-converting particles 144 and the second light emitted by the wavelength-converting particles 144 to have a high light extraction efficiency, the adhesive 142 has a higher penetration of the first light and the second light. The rate is better, for example, the transmission rate is greater than 80%, 90%, 95%, or 99%.

The material of the adhesive 142 may be a thermosetting resin, and the thermosetting resin may be an epoxy resin or a silicone resin. In one embodiment, the adhesive 142 is a silicone resin, and the composition of the silicone resin can be adjusted according to the required physical or optical properties. In one embodiment, the adhesive 142 contains an aliphatic siloxane resin, such as a methylsiloxane compound, and has a large ductility, and can withstand the thermal stress generated by the light emitting device 110. In another embodiment, the adhesive 142 contains an aromatic silicone resin, for example, a phenylsiloxane compound, which has a larger refractive index than a methylsiloxane compound, and can improve the light extraction efficiency of the light emitting device 110. . The smaller the difference between the refractive index of the adhesive 142 and the refractive index of the material of the light emitting surface of the light-emitting element 120 is, the larger the light emitting angle is, and the efficiency of light extraction can be further improved. In one embodiment, the material of the light emitting surface of the light-emitting element 120 is sapphire, and its refractive index is about 1.77. The material of the adhesive 142 is an aromatic silicone resin, and its refractive index is greater than 1.50.

The material of the wavelength conversion particles 144 may include an inorganic phosphor, an organic molecular fluorescent colorant, a semiconductor material, or a combination thereof. The semiconductor material includes a semiconductor material of a nano crystal, such as a quantum-dot light-emitting material. In one embodiment, the material of the wavelength conversion particles 144 is a phosphor, which may be selected from the group consisting of Y ₃ Al ₅ O ₁₂ : Ce, Gd ₃ Ga ₅ O ₁₂ : Ce, Lu ₃ Al ₅ O ₁₂ : Ce, (Lu, Y) ₃ Al ₅ O ₁₂ : Ce, Tb ₃ Al ₅ O ₁₂ : Ce, SrS: Eu, SrGa ₂ S ₄ : Eu, (Sr, Ca, Ba) (Al, Ga) ₂ S ₄ : Eu , (Ca, Sr) S: (Eu, Mn), (Ca, Sr) S: Ce, (Sr, Ba, Ca) ₂ Si ₅ N ₈ : Eu, (Sr, Ba, Ca) (Al, Ga) _{si N 3: Eu, SrLiAl 3} N 4: Eu 2+, CaAlSi ON: Eu, (Ba, Sr, Ca) 2 SiO 4: Eu, (Ca, Sr, Ba) 8 MgSi 4 O 16 (F, Cl, Br) ₂ : Eu, (Ca, Sr, Ba) Si ₂ O ₂ N ₂ : Eu, K ₂ SiF ₆ : Mn, K ₂ TiF ₆ : Mn, and K ₂ SnF ₆ : Mn. The semiconductor material may include a group II-VI semiconductor compound, a group III-V semiconductor compound, a group IV-VI semiconductor compound, or a combination thereof. The quantum dot light emitting material may include a core region that mainly emits light and a shell covering the core region. The material of the core region may be selected from the group consisting of zinc sulfide (ZnS), zinc selenide (ZnSe), and zinc telluride (ZnTe), zinc oxide (ZnO), cadmium sulfide (CdS), cadmium selenide (CdSe), cadmium telluride (CdTe), lead cesium chloride (CsPbCl ₃ ), lead cesium bromide (CsPbBr ₃ ), iodide cesium lead (CsPbI _3), gallium nitride (GaN), gallium phosphide (GaP), gallium selenide (GaSe), gallium antimonide (GaSb), gallium arsenide (GaAs), aluminum nitride (AlN), phosphorus Aluminum (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), zinc cadmium selenium sulfide (ZnCdSeS), and copper indium sulfide (CuInS).

The wavelength conversion layer 140 may cover one or more light emitting surfaces of the light emitting element 120. In one embodiment, the light emitting surface of the light emitting element 120 includes an upper surface 121 and a side surface 125, and the wavelength conversion layer 140 covers the upper surface 121 and the side surface 125 of the light emitting element 120 at the same time. In addition, in one embodiment, the wavelength conversion layer 140 is in direct contact with the upper surface 121 and the side surfaces 125 of the light emitting element 120. In another embodiment, the wavelength conversion layer 140 covers only the upper surface 121 (not shown) of the light emitting element 120.

The reflection fence 160 surrounds the light-emitting element 120 and the wavelength conversion layer 140. In this way, the reflection fence 160 can reflect the first light emitted by the light-emitting element 120 and the second light converted by the wavelength conversion layer 140 and then emit light from the top surface 102 of the light-emitting device 100. In one embodiment, the reflection fence 160 surrounds the side surface 125 of the light emitting element 120 and the side surface of the wavelength conversion layer 140 and exposes the upper surface 121 of the light emitting element 120 and the upper surface 141 of the wavelength conversion layer 140. In one embodiment, there is a gap between the reflection fence 160 and the wavelength conversion layer 140, and the reflection fence 160 is higher than the wavelength conversion layer 140. In this way, a part of the light emitted from the upper surface 141 of the wavelength conversion layer 140 can be reflected by the reflection fence 160, which can improve the light extraction rate when the light emitting device 100 is connected to the optical element. Specifically, referring to FIG. 2, the light-emitting device 220 functions as a light source, emits a light ray L1, and passes through an optical element 240 to emit light L2. When all the light rays L1 are within the angle θ ₁ , it means that the light rays L1 can be used by the optical element 240. In other words, the etendue of the light source is smaller than the etendue of the system. If the light ray L1 is within a larger angle θ ₂ , some light sources cannot be used by the optical element 240. Through the present invention, a high reflection fence 160 designed for the wavelength conversion layer 140, so that more light L1 can fall within the angle θ _1, the light extraction efficiency can be improved. Referring to FIG. 1A, in an embodiment, the top surface 162 of the reflection fence 160 is higher than the upper surface 141 of the wavelength conversion layer 140 (ie, the height h of the step) is between 5 micrometers (μm) and 100 micrometers. The light emitting device 100 The light emitting angle is between 110 degrees and 118 degrees. The light emission angle refers to an angle corresponding to half of the maximum light intensity. In another embodiment, the step difference h is between 5 micrometers (μm) and 50 micrometers. When the step difference h is less than 5 micrometers, the light emission angle is about 120 °. Therefore, the light emitting device 100 having a height difference between 5 μm and 100 μm is different from the light emitting device 100 having a height difference of less than 5 μm (comparative example), and the light emission angle between the two is between 2 degrees and 10 degrees. When the step difference h is greater than 100 micrometers, when the light-emitting device 100 is matched with an optical element (refer to FIG. 5), the reflection fence 160 and the optical element are very close, so the reflection fence 160 may interfere with the optical element. In one embodiment, the height h of the step difference, the height of the wavelength conversion layer 140, and the thickness of the reflective layer 150 are added to approximately the entire thickness H of the light emitting device 100, where the ratio of h to H (h / H) is 0.01. To 0.4. In another embodiment, the ratio of h to H (h / H) is between 0.015 and 0.2. Within the aforementioned h / H ratio range, on the one hand, the reflection effect of the reflection fence 160 can be improved, and on the other hand, the height required for the wavelength conversion layer 140 in the light emitting device 100 can also be satisfied.

In one embodiment, the reflective fence 160 includes a 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 reflective particles are titanium oxide, and the weight percentage of titanium oxide relative to the reflective fence 160 is not less than 60%. In another embodiment, the weight percentage of titanium oxide relative to the reflective fence 160 is 20% to 60%. between. In one embodiment, the thickness T of the reflective fence 160 is between 20 micrometers (μm) and 200 micrometers.

The reflection layer 150 is formed on the bottom surfaces of the light-emitting element 120, the wavelength conversion layer 140, and the reflection fence 160. In one embodiment, the reflective layer 150 directly contacts the light emitting element 120 (as shown in the figure). In another implementation, the reflective layer 150 does not directly contact the light emitting element 120 (not shown). The reflective layer 150 forms a plurality of through holes to expose the contact electrodes 126a and 126b. In one embodiment, the reflective layer 150 can reflect the light emitted by the light emitting device 100, so the light emitting efficiency of the light emitting device 100 can be improved. In one embodiment, the reflective layer 150 includes a binder (not shown) and reflective particles (not shown) dispersed in the binder. The material of the adhesive may be a silicone resin or an epoxy resin. The material of the reflective particles includes titanium oxide, aluminum oxide, or zinc oxide. In addition, the reflective layer 150 surrounding the conductive portion 180 can also reduce the risk of a short circuit between the conductive portions 182 and 184.

The conductive portions 180 are respectively filled in the through holes and surrounded by the reflective layer 150. The conductive portion 180 can be used as a physical and electrical connection between the contact electrodes 126a and 126b of the light-emitting element 120 and a circuit board (not shown). The higher the bonding strength between the conductive portion 180 and the conductive pads 126a and 126b, the less likely it is that peeling will occur. As the material of the conductive portion 180, a conductive metal material with a lower melting point can be used. In one embodiment, the temperature of the melting point (or liquefaction point) of the material of the conductive portion 180 is preferably not higher than 280 ° C. In another embodiment, the material of the conductive portion 180 includes pure tin or a tin alloy. Types of tin alloys: Sn / Ag alloy, Sn / Ag / Cu alloy, Sn / Cu alloy, Sn / Pb alloy, or tin Antimony alloy (Sn / Sb alloy). The conductive portion 180 may have a single-layer or multi-layer structure. In one embodiment, the conductive portion 180 has a single-layer structure and a material is a tin alloy. In yet another embodiment, the conductive portion 180 has a multi-layered structure. Metals that are close to or in direct contact with the contact electrodes 126a and 126b have higher melting points; metals that are far from or that do not directly contact the contact electrodes 126a and 126b have lower melting points. In one embodiment, the high-melting metal is a tin-antimony alloy (a first tin alloy), and the low-melting metal is a tin-silver-copper alloy (a second tin alloy). In another embodiment, the high-melting metal is copper, and the low-melting metal is a tin alloy (including but not limited to tin-antimony alloy, tin-silver-copper alloy).

FIG. 3A, FIG. 3F, and FIG. 3H to FIG. 3K are flowcharts of manufacturing a light emitting device according to an embodiment of the present invention. Referring to FIG. 3A, a temporary substrate 312, an adhesive layer 314 is formed on the temporary substrate 312, and light emitting elements 120a, 120b, and 120c are located on the adhesive layer 314. The number of light emitting elements is only here. As an example, it is not limited to three, and may be more or less than three. In one embodiment, the temporary substrate 312 is a glass, sapphire substrate, metal or plastic material, which can be used as a support. The adhesive layer 314 can be used for temporary fixing of the light-emitting elements 120a, 120b, and 120c. In one embodiment, the adhesive layer 314 is a thermal curing adhesive. At this step, the adhesive layer 314 is not completely cured but still has adhesiveness. In another embodiment, the adhesive layer 314 may be a photo curing adhesive.

Referring to FIG. 3B, a wavelength conversion film 140 'is formed on the adhesive layer 314 and covers the light emitting elements 120a, 120b, and 120c at the same time. The wavelength conversion film 140 'is formed on the light emitting elements 120a, 120b, 120c and the temporary substrate 312 after mixing a plurality of wavelength conversion particles with an adhesive. Forming methods include: direct coating, mold forming, or pre-formed sheet structures. Direct coating can be by dispensing or spraying. The size of the sheet structure can be adjusted according to requirements. For example, the sheet structure includes several wavelength conversion sheets separated from each other. The several wavelength conversion sheets separated from each other can cover several light emitting elements in batches or sequentially, that is, one The wavelength conversion film 140 'covers only one or a part of the light emitting elements (for example, 1/50, 1/100, or 1/200 or less of the total number of light emitting elements on the temporary substrate 312). As another example, the sheet structure is a tape, which can cover several light emitting elements continuously and at once, that is, a wavelength conversion sheet covers most or all light emitting elements on a temporary substrate at the same time (for example, temporarily 1/50, 1/100, 1/200 or more of the total number of light emitting elements on the substrate).

Referring to FIG. 3C, the wavelength conversion film 140 'is divided into a plurality of wavelength conversion layers 140a, 140b, and 140c through a separate process. This separation process can be the first separation. Prior to the separation process, the wavelength conversion film 140 'may be cured. In one embodiment, the wavelength conversion film 140 'is cured by heating. In another embodiment, other types of energy can be used to cure the wavelength conversion film 140 ', such as radiation. The separate process includes cutting the wavelength conversion film 140 'and a part or all of the adhesive layer 314 with a cutting tool 331 to form a cutting track.

Referring to FIG. 3D, a reflective layer 160 '(second reflective layer) is formed on the plurality of wavelength conversion layers 140a, 140b, 140c and the temporary substrate 312. In one embodiment, the reflective layer 160 'covers all the upper surfaces and sidewalls of the wavelength conversion layers 140a, 140b, 140c. In addition, the reflective layer 160 'is in direct contact with the surface of the adhesive layer 314. The reflective layer 160 'can be formed by laminating or molding. In one embodiment, the reflective particles have been pre-formed into a sheet structure after being mixed with the bonding agent in advance. The sheet structure is heated and pressure is applied so that the reflective layer 160 'covers the upper surfaces of the wavelength conversion layers 140a, 140b, and 140c. And filling in the recesses or cutting lines between the light emitting elements 120a, 120b, 120c. The reflective layer 160 'at this stage is still in a semi-cured state, or is called a B-stage adhesive. In one embodiment, the reflective layer 160 'can be cured by heating. The heated reflective layer 160 'is converted to a fully cured state, or is called a C-stage reflective layer 160'. In other embodiments, the reflective layer 160 'is formed by coating or laminating a film material. In one embodiment, the reflective particles and the bonding agent are mixed and then directly coated on the wavelength conversion layers 140a, 140b, 140c to form a reflective layer 160 '. In another embodiment, other types of energy can be used to cure the reflective layer 160 ', such as UV light.

Referring to FIGS. 3E and 3F, a part of the reflective layer 160 'above the wavelength conversion layers 140a, 140b, and 140c is removed to form a reflective frame 160' '. The wavelength conversion layers 140a, 140b, and 140c are exposed from the reflection layer 160 ', and the reflection frame 160' 'and the wavelength conversion layers 140a, 140b, and 140c have a stepped structure. In an embodiment, referring to FIG. 1A, the step difference h is between 5 micrometers (μm) and 50 micrometers. In one embodiment, the reflection layer 160 'is removed by adhering a part of the reflection layer 160' on the upper surface of the wavelength conversion layers 140a, 140b, 140c and the surroundings to the roller 370 through a roller 370. Specifically, since the adhesive force of the reflective layer 160 'and the wavelength conversion layers 140a, 140b, and 140c is smaller than the breaking strength of the reflective layer 160' itself, and the breaking strength of the reflective layer 160 'itself is less than the adhesion of the roller 370 to the reflective layer 160' force. Therefore, a frame 390 is used to define the required height of the reflection frame 160 ". The height of the frame 390 will be slightly higher than the height of the wavelength conversion layers 140a, 140b, 140c. When the roller 370 rolls over the reflection layer 160 ', the wavelength conversion will be taken away. Part of the reflective layer 160 'on the upper surface of the layers 140a, 140b, 140c, so a stepped structure will be generated between the reflective frame 160 "and the wavelength conversion layers 140a, 140b, 140c.

Referring to FIG. 3H, the temporary substrate 312 and the adhesive layer 314 are removed, and transferred to another temporary substrate 352 and another adhesive layer 354 before the temporary substrate 312 and the adhesive layer 314 are removed. The materials of the temporary substrate 352 and the temporary substrate 312 may be the same or similar. The materials of the adhesive layer 354 and the adhesive layer 314 may also be the same or similar, such as a thermal dissociation glue or a thermal curing glue.

Referring to FIG. 3I, a plurality of conductive portions 180a, 180b, and 180c are formed on the contact electrodes 126a, 126b, and 126c, respectively. In one embodiment, the material of the conductive portions 180a, 180b, and 180c is solder, and can be formed on the contact electrodes 126a, 126b, and 126c by reflow. In one embodiment, the reflow temperature is between 160 ° C and 260 ° C.

Referring to FIG. 3J, reflective layers 150 'and 150' '(first reflective layers) are formed on the surface of the light-emitting layer 124 (the upper surface in the figure) and the surface of the reflective frame 160' '(the upper surface in the figure) and covering The contact electrodes 126a, 126b, and 126c and the conductive portions 180a, 180b, and 180c. After that, the reflective layer 150 '' is removed to expose the conductive portions 180a, 180b, 180c.

Referring to FIG. 3K, the reflection frame 160 '' is divided into a plurality of reflection fences 160a, 160b, 160c and the reflection layer 150 'is divided into a plurality of reflection layers 150 through a separation process. This separation process can be a second separation. The separate process includes cutting the reflective frame 160 '', the reflective layer 150 ', and some or all of the adhesive layer 354 with a cutting tool 333 to form a cutting track. After this step, light emitting devices 100a, 100b, and 100c can be formed.

FIG. 3A to FIG. 3G are flowcharts of manufacturing a light emitting device according to another embodiment of the present invention. The difference from the above embodiment is that the embodiment does not include the reflective layer 150 and the conductive portions 180a, 180b, and 180c.

After removing a part of the reflective layer 160 'on the upper surface of the wavelength conversion layers 140a, 140b, and 140c to form a reflective frame 160' '(FIGS. 3E and 3F), referring to FIG. 3G, the reflective frame is separated through a separate process. 160 "is divided into multiple reflective fences 160a, 160b, 160c. This separation process can be a second separation. The separate process includes cutting the reflective frame 160 '' and a part or all of the adhesive layer 314 with a cutting tool 332 to form a cutting track.

FIG. 3A to FIG. 3B and FIGS. 4A to 4F are flowcharts of manufacturing a light emitting device according to another embodiment of the present invention. A wavelength conversion layer 140 'is formed on the adhesive layer 314 and simultaneously covers the light emitting elements 120a, 120b, and 120c (FIG. 3B). In an embodiment, referring to FIG. 4A, a temporary layer 430 'is covered on the wavelength conversion layer 140'. One of the purposes of the temporary layer 430 'is to form a step between the reflection frame 160' 'and the wavelength conversion layers 140a, 140b, and 140c in the subsequent steps. The material of the temporary layer 430 'may be a photo-curable resin or a thermo-curable resin. In one embodiment, the temporary layer 430 'is a film layer formed of a photo-curable resin, and is formed after being irradiated with light having a specific wavelength, such as ultraviolet light.

Referring to FIG. 4B, the wavelength conversion layer 140 'is divided into a plurality of wavelength conversion layers 140a, 140b, and 140c through a separate process, and the temporary layer 430' is divided into a plurality of temporary layers 430a, 430b, and 430c. This separation process can be the first separation. The plurality of temporary layers 430a, 430b, and 430c each correspond to the plurality of wavelength conversion layers 140a, 140b, and 140c.

Referring to FIG. 4C, a reflective layer 460 '(first reflective layer) is formed on a plurality of wavelength conversion layers (140a, 140b, 140c), a plurality of temporary layers (430a, 430b, 430c), and a temporary substrate 312 and adhesive Above layer 314. For the function and method of forming the reflective layer 460 ', please refer to FIG. 3D and related paragraphs.

Referring to FIG. 4D, a part of the reflective layer 460 'on the temporary layers 430a, 430b, and 430c is removed to form a reflective frame 460' '. In an embodiment, the upper surface of the reflective frame 460 "may be mechanically ground, wet-bonded, or a combination of the two, so that the upper surface of the reflective frame 460" and the temporary layers 430a, 430b, 430c of.

Referring to FIG. 4E, the temporary layers 430a, 430b, and 430c are removed to expose the wavelength conversion layers 140a, 140b, and 140c. This step can form a step structure between the wavelength conversion layers 140a, 140b, 140c and the reflection frame 460 ''.

Referring to FIG. 4F, the reflection frame 460 '' is divided into a plurality of reflection fences 460a, 460b, and 460c through a separate process. This separation process can be a second separation. The separate process includes cutting the reflective frame 460 '' and a part or all of the adhesive layer 354 with a cutting tool to form a cutting track. After this step, the light emitting devices 400a, 400b, and 400c can be formed.

FIG. 5 shows a light emitting module 500 according to an embodiment of the present invention. The light-emitting module 500 includes a first light-emitting device 520a, a second light-emitting device 520b, a carrying plate 540, and an optical element 560. The first light emitting device 520a and the second light emitting device 520b are formed on the carrier plate 540, respectively, and the optical element 560 covers the first light emitting device 520a and the second light emitting device 520b. In one embodiment, the first light emitting device 520a includes a first light emitting element 522a, a first wavelength conversion layer 524a, and a first reflection fence 526a. The second light emitting device 520b includes a second light emitting element 522b, a second wavelength conversion layer 524b, and a second reflection fence 526a. In this embodiment, the first light emitting device 520a and the second light emitting device 520b can emit light with different color temperatures. In one embodiment, the first wavelength conversion layer 524a and the second wavelength conversion layer 524b have different wavelength conversion layers, so the color temperatures of the first light emitting device 520a and the second light emitting device 520b are different. Different wavelength conversion layers may refer to different wavelength conversion materials, the same wavelength conversion material but different concentrations or the same wavelength conversion material but different ratios. In one embodiment, the color temperature of the first light emitting device 520a is between 1800K and 3000K, and the color temperature of the second light emitting device 520b is between 4000K and 7000K. In one embodiment, the color temperature difference between the first light-emitting device 520a and the second light-emitting device 520b is greater than 2000K, so that the light-emitting module 500 can emit light with two different color temperatures. The light emitting module 500 can be applied to the flash in electronic products. Through the design of light sources with different color temperatures, it can provide more detailed white balance processing in different environments, so it can be closer to the real image.

In one embodiment, the carrier board 540 is a circuit board and has circuit layers 542a and 542b electrically connected to the first light emitting device 520a and the second light emitting device 520b, respectively. In one embodiment, the optical element 560 is a Fresnel lens. The Fresnel lens has two sets of concentric circular lines that face the first light emitting device 520a and the second light emitting device 520b, respectively. In this way, the first light-emitting device 520a and the second light-emitting device 520b can emit light through a Fresnel lens in an approximately or equivalent parallel light manner.

6A and 6B are a cross-sectional view and a top view, respectively, of a light-emitting device 600 according to another embodiment of the present invention. The light emitting device 600 includes a light emitting element 620, a wavelength conversion layer 640, a reflection fence 660, a reflection layer 650, and a conductive portion 680. The difference from FIG. 1 is that the reflection fence 660 has an inclined surface. In one embodiment, the inclined surface is located on the inner surface of the reflective fence 660, that is, the surface facing the light emitting element 620. Specifically, the inner surface of the reflection fence 660, the upper surface of a wavelength conversion layer 640, the bottom surface of the light-emitting element 620, and the top surface of the reflection layer 650 may form an inverted trapezoidal structure. The reflection fence 660 has a light emitting device 600 with an inclined surface, which can change the traveling direction of the light in the light emitting device 600 and reduce the light emitting angle. For specific structures, functions, and formation methods of the light emitting element 620, the wavelength conversion layer 640, the reflection fence 660, the reflection layer 650, and the conductive portion 680, reference may be made to FIG. 1 and corresponding paragraphs.

The above-mentioned embodiments are only for explaining the technical ideas and characteristics of the present invention. The purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. When the scope of the patent of the present invention cannot be limited, That is, any equivalent changes or modifications made in accordance with the spirit disclosed in the present invention should still be covered by the patent scope of the present invention.

100, 100a, 100b, 100c, 220, 520a, 520b, 600‧‧‧ light-emitting devices

102‧‧‧Top surface

104‧‧‧ bottom surface

106‧‧‧ side

120, 120a, 120b, 120c, 522a, 522b, 620‧‧‧ light-emitting elements

121‧‧‧ Top surface

122‧‧‧ Carrier substrate

123‧‧‧ lower surface

124‧‧‧Light-emitting layer

125‧‧‧ side

126, 126a, 126b, 126c ‧‧‧ contact electrode

140, 140a, 140b, 140c, 524a, 524b, 640‧‧‧ wavelength conversion layer

140’‧‧‧wavelength conversion film

141‧‧‧upper surface

142‧‧‧Adhesive

144‧‧‧wavelength conversion particle

150, 160 ’, 460’, 526a, 526b, 650‧‧‧ reflective layer

160, 160a, 160b, 160c, 460a, 460b, 460c, 526a, 526b, 660‧‧‧ reflection fence

160 ’’, 460 ’’ ‧‧‧ reflection frame

162‧‧‧Top

180, 180a, 180b, 180c, 182, 184, 680‧‧‧ conductive section

240, 560‧‧‧optical components

312, 352‧‧‧Temporary substrate

314, 354‧‧‧ adhesive layer

331, 332, 332, 534‧‧‧ cutting tools

370‧‧‧roller

390‧‧‧Frame

430 ’, 430a, 430b, 430c‧‧‧Temporary layers

500‧‧‧light emitting module

540‧‧‧ carrier board

542a, 542b‧‧‧Circuit layer

h‧‧‧step difference height

H‧‧‧Overall thickness

T‧‧‧thickness

FIG. 1A is a cross-sectional view showing a light emitting device according to an embodiment of the present invention.

FIG. 1B is a top view of the light emitting device in FIG. 1A.

FIG. 2 shows a light emitting angle of a light emitting device according to an embodiment of the present invention.

FIG. 3A to FIG. 3F and FIG. 3H to FIG. 3K are flowcharts of manufacturing a light emitting device according to an embodiment of the present invention.

FIG. 3A to FIG. 3G are flowcharts of manufacturing a light emitting device according to another embodiment of the present invention.

FIG. 3A to FIG. 3B and FIGS. 4A to 4F are flowcharts of manufacturing a light emitting device according to another embodiment of the present invention.

FIG. 5 shows a light emitting module according to an embodiment of the present invention.

FIG. 6A is a cross-sectional view showing a light emitting device according to another embodiment of the present invention.

Fig. 6B is a top view showing the light emitting device in Fig. 6A.

no

no

Claims (10)

A light-emitting device includes: a light-emitting element including a first upper surface, a lower surface, and a plurality of first side surfaces between the upper surface and the lower surface; a wavelength conversion layer including a plurality of wavelength conversion particles, and including A second upper surface directly above the first upper surface; and a reflective fence surrounding the plurality of first sides, wherein the reflective fence has a top surface with a space between the top surface and the second upper surface One step, wherein the light emitting device has a light emitting angle, and the light emitting angle is between 110 degrees and 118 degrees. For example, the light-emitting device according to the first patent application range, wherein the top surface is higher than the second upper surface by 5 to 100 microns. For example, the light-emitting device of the first patent application range, wherein the top surface is h above the second upper surface, the height of the light-emitting device is H, and the ratio of h to H (h / H) is between 0.01 and 0.4. between. For example, the light-emitting device according to the first item of the patent application scope, wherein the light-emitting device has a color temperature between 1800K and 7000K. For example, the light-emitting device according to item 1 of the patent application scope, wherein the reflective fence has a thickness between 20 micrometers and 200 micrometers. For example, the light-emitting device according to the first patent application scope further includes a reflective layer formed on the lower surface. For example, the light-emitting device according to item 6 of the patent application scope further includes a conductive portion surrounded by the reflective layer. For example, the light-emitting device according to the first patent application range, wherein the reflective fence includes an inner surface, and the inner surface has an inclined surface. A light-emitting module includes: a carrier board having a circuit layer; for example, the light-emitting device of the first patent application scope can emit a light and is formed on the carrier board to be electrically connected to the circuit layer; and an optical element , Covering the light emitting device. For example, the light-emitting module of item 9 of the patent application scope, wherein the optical element includes a Fresnel lens.