Composite encapsulation film and method for manufacturing light-emitting device using same

Abstract

The invention discloses a composite packaging film and a manufacturing method of a light-emitting device using the composite packaging film. The manufacturing method of the light-emitting device comprises the following steps: providing a substrate; providing a light-emitting structure, wherein the light-emitting structure comprises a plurality of solid-state light sources which are arranged on a substrate; and providing a composite encapsulation film for encapsulating the light-emitting structure. The composite packaging film comprises a semi-cured light-transmitting layer with a front surface and a back surface, and a plurality of first reflecting layers arranged on the front surface of the semi-cured light-transmitting layer at intervals. The method further comprises the steps that the back surface of the semi-cured light-transmitting layer of the composite packaging film is pressed towards the solid-state light sources of the light-emitting structure so that the solid-state light sources can be embedded in the semi-cured light-transmitting layer and correspond to the first reflecting layers in position, and a heating manufacturing process is executed on the composite packaging film so that the semi-cured light-transmitting layer can be cured.

Description

TECHNICAL FIELD

[0001] The present application relates to packaging technology, in particular to a composite packaging film and a manufacturing method of a light emitting device using the same. BACKGROUND

[0002] A light emitting diode (LED) is a light emitting element made of a semiconductor material, which can convert electric energy into light. The LED has advantages of small size, high energy conversion efficiency, long service life, and power saving, and is thus widely used as a light source in various electronic devices.

[0003] Chip on board (COB) technology is to directly package LED chips on a module substrate, and then to integrally package each large unit. However, the existing COB packaging technology is not satisfactory in all aspects. SUMMARY

[0004] The present application provides a manufacturing method of a light emitting device. The method includes providing a substrate, providing a light emitting structure including a plurality of solid state light sources disposed on the substrate, and providing a composite packaging film to package the light emitting structure. The composite packaging film includes a semi-cured light transmissive layer having a front surface and a back surface, and a plurality of first reflective layers disposed at intervals on the front surface of the semi-cured light transmissive layer. The method further includes pressing the back surface of the semi-cured light transmissive layer of the composite packaging film towards the solid state light sources of the light emitting structure so that the solid state light sources are embedded in the semi-cured light transmissive layer and correspond to positions of the first reflective layers, respectively, and performing a heating manufacturing process on the composite packaging film to cure the semi-cured light transmissive layer.

[0005] The present application provides a manufacturing method of a light emitting device. The method includes providing a substrate, providing a light emitting structure including a plurality of solid state light sources disposed on the substrate, and providing a composite packaging film to package the light emitting structure. The composite packaging film includes a semi-cured light transmissive layer having a front surface and a back surface, a plurality of first reflective layers disposed at intervals on the front surface of the semi-cured light transmissive layer, and a second reflective layer on the back surface of the semi-cured light transmissive layer, and the second reflective layer has a plurality of openings to expose a part of the back surface of the semi-cured light transmissive layer, and the openings correspond to positions of the first reflective layers, respectively. The method further includes aligning the openings of the second reflective layer of the composite packaging film with the solid state light sources of the light emitting structure, respectively, pressing the back surface of the semi-cured light transmissive layer exposed by the openings towards the solid state light sources so that the solid state light sources are embedded in the semi-cured light transmissive layer and correspond to positions of the first reflective layers, respectively, and performing a heating manufacturing process on the composite packaging film to cure the semi-cured light transmissive layer.

[0006] The present invention provides a composite packaging film for encapsulating a light-emitting structure, and the composite packaging film includes: a semi-cured light-transmitting layer having a front surface and a back surface, and a plurality of first reflective layers spaced apart on the front surface of the semi-cured light-transmitting layer, and the first reflective layers are in direct contact with the semi-cured light-transmitting layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Various aspects of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that, in accordance with standard industry practice, various components are not drawn to scale and are provided for illustrative purposes only. In fact, the dimensions of the components may be arbitrarily enlarged or reduced to clearly illustrate the components of the embodiments of the present invention. It should also be noted that the accompanying drawings illustrate only typical embodiments of the present invention and should not be considered to limit its scope. The present invention is equally applicable to other embodiments.

[0008] Figures 1 to 6 10 is a schematic cross-sectional view of a light emitting device using a composite encapsulation film at various manufacturing stages according to some embodiments of the present invention;

[0009] Figure 7A 1 is a schematic top view of a light emitting device according to some embodiments of the present invention;

[0010] Figure 7B Some embodiments of the present invention are shown. Figure 7A A schematic cross-sectional view of the light emitting device along reference cross-section AA;

[0011] Figures 8A to 13 10 is a schematic cross-sectional view of other embodiments of the present invention illustrating various manufacturing stages of a light-emitting device using a composite encapsulation film having a second reflective layer;

[0012] Figures 14 to 18 1 and 2 are further embodiments of the present invention, illustrating cross-sectional schematic diagrams of light-emitting devices using a composite packaging film at various manufacturing stages, wherein the second reflective layer is embedded in the semi-cured light-transmitting layer.

[0013] Description of Reference Symbols 100: Light-emitting structure

[0014] 102: Substrate

[0015] 104: Light Emitting Diode

[0016] 200: Composite packaging film

[0017] 202: First carrier board

[0018] 206: Semi-cured light-transmitting layer

[0019] 206': Curing the light-transmitting layer

[0020] 206B: Back surface

[0021] 206F: front surface

[0022] 208: first reflective layer

[0023] 220 / 220': composite encapsulation film

[0024] 222: second carrier

[0025] 224: opening

[0026] 226: another additional semi- hardened light transmissive layer

[0027] 226B: first surface

[0028] 226F: second surface

[0029] 228: second reflective layer

[0030] 228B: back surface

[0031] 228F: front surface

[0032] 240: composite encapsulation film

[0033] 300: light emitting device

[0034] 310 / 312 / 314 / 316 / 318 / 319: compression

[0035] 320 / 322 / 324: heating fabrication process

[0036] 400: light emitting device

[0037] L1 / L2: light path DETAILED DESCRIPTION

[0038] The following disclosure provides many different embodiments, or examples, for implementing different components of the provided subject matter. Each of the various embodiments and implementations can be used alone or in combination with one another. Many embodiments and examples are described below to illustrate the disclosure. However, the disclosure is not limited to the embodiments and examples described below. The disclosure is defined by the claims and their equivalents. For example, if a first element is described as being formed on a second element, this can include embodiments where the first and second elements are in direct contact, and can also include embodiments where one or more additional elements are formed between the first and second elements so that they are not in direct contact. Furthermore, the disclosure can refer to a number and / or letter that is repeated in various examples. Such repetition is for the purpose of clarity and conciseness, and is not intended to indicate a relationship between the different embodiments and / or configurations being discussed.

[0039] Furthermore, relative terms such as "below" or "lower", "above" or "higher", or the like can be used herein for ease of description to describe one (a plurality) component or constituent(s) or positional relationship between the component(s) or constituent(s) and another (a plurality) component or constituent(s) or positional relationship between the component(s) or constituent(s) in the drawings. The relative terms are used to include different orientations of the device in use or operation, and the orientations described in the drawings. When the device is turned to a different orientation (rotated 90 degrees or other orientations), the relative terms used therein will also be interpreted according to the turned orientation.

[0040] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the inventive concept. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of this specification and the relevant art and will not be interpreted in an overly literal or overly formal sense unless expressly so defined herein.

[0041] It is to be understood that the embodiments which follow can be substituted, combined, or recombined to form other embodiments without departing from the spirit of the present application. Features of the various embodiments can be combined, coupled, or recombined as long as they do not conflict with each other or the spirit of the present application.

[0042] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an overly literal or overly formal sense unless expressly so defined herein.

[0043] One of the existing LED packaging technologies is to completely cover the substrate and a plurality of light emitting diodes disposed on the substrate by a full coating of encapsulation glue. Since the encapsulation glue has fluidity, a dam is needed to be disposed around the light emitting diodes to limit the coverage range of the encapsulation glue. Then, the uneven surface of the encapsulation glue is planarized by a planarization manufacturing process to achieve the surface flatness required by the product specification. This way of coating a large amount of encapsulation glue first and then removing the excess encapsulation glue increases the cost due to the high material removal rate of the encapsulation glue. In addition, after performing a heating manufacturing process to solidify the encapsulation glue, an additional heating manufacturing process is needed to solidify the reflective layer. Therefore, the existing LED packaging technology not only has high process complexity and long manufacturing process time, but also affects the yield, causing the product competitiveness to decline.

[0044] The present invention provides a composite packaging film and a manufacturing process method for a light-emitting device using the same. Compared with the aforementioned existing LED packaging technology, the semi-cured light-transmitting layer and the first reflective layer provided by the present invention are pressed together with the light-emitting structure in the form of a composite packaging film, and the setting of the packaging film (for example, the semi-cured light-transmitting layer) and the reflective layer (for example, the first reflective layer) can be completed at the same time, which can simplify the process and shorten the manufacturing process time, thereby improving the yield and reducing the cost. In addition, since the composite packaging film provided by the present invention has low fluidity, there is no need to set up additional retaining walls around the light-emitting diode, which can simplify the process and reduce the cost. Furthermore, the use of the composite packaging film provided by the present invention can avoid the problem of high packaging glue rejection rate in the existing LED packaging technology, thereby reducing the cost.

[0045] In some embodiments of the present invention, unless otherwise defined, the term "semi-cured state" (also referred to as a semi-baked state or a temporarily cured state) refers to a state in which an adhesive material is in the B-stage state after being preheated (e.g., baked at a temperature of 90°C to 120°C for 15 to 25 minutes). In other words, the adhesive material is solid at room temperature while having reactivity and a certain degree of fluidity. It can be converted to the C-stage state, i.e., the "cured state", by further heating (e.g., baking at a temperature of 130°C to 170°C for 2 to 4 hours).

[0046] In some embodiments of the present invention, unless otherwise defined, the term "semi-cured light-transmitting layer" refers to a film layer in a semi-cured state and is resistant to solid-state light sources (e.g., Figure 1 The transmittance of the light emitting diode 104 at the light emitting wavelength is greater than about 85% (eg, greater than 90%).

[0047] Figures 1 to 6 FIG2 is a cross-sectional view of a light emitting device 300 using a composite packaging film 200 at various stages of manufacture according to some embodiments of the present invention. It should be understood that additional embodiments of the method may be Figures 1 to 6 Additional operations are provided before, during, and after the steps shown, and some of the steps described below may be replaced or deleted in additional embodiments of the method. The order of the steps / processes is not limited and may be interchanged.

[0048] refer to Figure 1 In one embodiment, a substrate 102 and a light-emitting structure 100 are provided. The light-emitting structure 100 includes a plurality of solid-state light sources disposed on the substrate 102. The solid-state light sources may be, for example, light-emitting diodes, light-emitting diode devices, or chip-scale package (CSP) light-emitting diodes. The following description uses the light-emitting diodes 104 as an example, but the present invention is not limited thereto.

[0049] In some embodiments, substrate 102 may be a substrate having conductive circuits, such as a rigid substrate, a flexible substrate, a sapphire substrate, a transparent substrate, an opaque substrate, a silicon substrate, a glass substrate, a printed circuit board (PCB), a metal substrate, a ceramic substrate, or the like or a combination thereof, but the present invention is not limited thereto. Substrate 102 is used to support electronic components (e.g., light-emitting diodes 104 and integrated circuits (ICs)) thereon, and the electronic components are electrically connected to the conductive circuits of the substrate.

[0050] In some embodiments, the spacing between LEDs 104 is in the range of 4 mm to 8 mm (e.g., 6 mm). In some embodiments, LEDs 104 may be sub-millimeter LEDs (mini LEDs) or micro LEDs (micro LEDs), but the present invention is not limited thereto.

[0051] refer to Figure 2 In one embodiment, a composite packaging film 200 is provided for packaging a light emitting structure (eg, Figure 1 In one embodiment, a first carrier 202 is provided, and first reflective layers 208 are spaced apart and disposed on the first carrier 202. In some embodiments, the first reflective layers 208 are disposed on the first carrier 202 at positions corresponding to the positions of the light-emitting diodes 104 on the substrate 102. This allows the first reflective layers 208 to be positioned above the light-emitting diodes 104 after the composite packaging film 200 is pressed against the light-emitting structure 100, thereby reflecting light emitted upward by the light-emitting diodes 104. This reduces the brightness of the light emitted upward by the light-emitting diodes 104, thereby improving the uniformity of the surface light emission of the light-emitting device 300. This will be discussed later in conjunction with the following. Figure 7B Provide detailed explanation.

[0052] In some embodiments, the first carrier 202 may include a release film having an anti-sticking property that prevents the release film from adhering to the first reflective layer 208. Vice versa, this anti-sticking property helps to prevent the first reflective layer 208 from being adhered to the first reflective layer 208 after being heated and cured (for example, Figure 6 The heating process 320 facilitates the removal of the first carrier 202 .

[0053] In one embodiment, the first reflective layer 208 can be a high molecular material containing doped reflective particles. In some embodiments, the high molecular material can include silicone, epoxy, acrylic, or a combination thereof. In some embodiments, the reflective particles can include titanium oxide, aluminum oxide, zirconium oxide, silicon oxide, or other suitable metal oxide. In some embodiments, the first reflective layer 208 has a reflectivity of greater than about 90% (e.g., greater than 95%) for the light emitting wavelength of the light emitting diode 104. In some embodiments, the first reflective layer 208 can partially reflect light and partially transmit light. The doping concentration of the reflective particles can be adjusted as desired.

[0054] In some embodiments, the first reflective layer 208 has a thickness in the range of 40 to 80 microns (e.g., 50 microns), but the present application is not limited thereto and the thickness of the first reflective layer 208 can be adjusted as desired. In some embodiments, the first reflective layer 208 has an area greater than the area of the solid state light source (e.g., the light emitting diode 104) for emitting light upward. Since the light intensity directly above the light emitting diode 104 is relatively high, it can cause the overall light emission of the light emitting device 300 to be non-uniform. By providing the first reflective layer 208, the light intensity emitted upward by the light emitting diode 104 can be reduced, and the overall light emission of the light emitting device 300 can be made more uniform.

[0055] In one embodiment, the first reflective layer 208 can be in a cured state or a semi-cured state. In some embodiments, the semi-cured first reflective layer 208 and the semi-cured light transmissive layer 206 can have a better adhesion. Figure 3

[0056] In some embodiments, the first reflective layer 208 can be formed on the first carrier 202 by coating or the like. Specifically, a steel sheet or a steel film (not shown) having a plurality of holes is first disposed on the first carrier 202, and then the first reflective layer material is coated (e.g., brushed) to fill in the holes. After the steel sheet or the steel film is removed, the first reflective layer material remaining on the first carrier 202 forms a plurality of first reflective layers 208.

[0057] Referring to Figure 3 In one embodiment, the first carrier 202 is flipped over so that the first reflective layer 208 is laminated 310 toward the front surface 206F of the semi-cured light transmissive layer 206, so that the first reflective layer 208 is in direct contact with the semi-cured light transmissive layer 206. The term "flipped over" means that the first carrier 202 is upside down, that is, the first carrier 202 is laminated 310 to the semi-cured light transmissive layer 206 with the first reflective layer 208 facing the front surface 206F of the semi-cured light transmissive layer 206. Figure 2 ​The upper surface of the semi-cured light-transmissive layer 206 becomes downward after the turning. It should be noted that since the semi-cured light-transmissive layer 206 has a flat front surface 206F, the planarization process in the prior LED packaging technology can be omitted before the pressing 310 of the first reflective layer 208 and the semi-cured light-transmissive layer 206, and the front surface 206F of the semi-cured light-transmissive layer 206 meets the surface flatness requirement of the product specification.

[0058] In some embodiments, the semi-cured light-transmissive layer 206 can be an organic glue, an inorganic glue, or any proportion mixture thereof, such as Silicone, Epoxy, Fluorine glue, etc. In an embodiment, the semi-cured light-transmissive layer 206 can be Silicone or Epoxy. In some embodiments, the thickness of the semi-cured light-transmissive layer 206 is in the range of 150 microns to 400 microns (e.g., 350 microns), but the present application is not limited thereto. Generally speaking, the thicker the semi-cured light-transmissive layer 206 is, the better the light uniformity of the light emitting surface of the light emitting device 300 is, and the thinner the semi-cured light-transmissive layer 206 is, the more conducive to the lightness and thinness of the product. Figure 7B

[0059] In some embodiments, any suitable molding process (e.g., vacuum lamination) can be used to press 310 the first reflective layer 208 and the semi-cured light-transmissive layer 206. In some embodiments, the pressing 310 is performed under the condition that the pressure is 0.1 MPa to 1 MPa (e.g., 0.1 MPa) and lasts for 2 minutes to 5 minutes (e.g., 3 minutes).

[0060] As shown in FIG. 1, in an embodiment, the present application provides a composite packaging film 200, which can include a semi-cured light-transmissive layer 206 and a plurality of first reflective layers 208, the semi-cured light-transmissive layer 206 has a front surface 206F and a back surface 206B, and the plurality of first reflective layers 208 are arranged at intervals on the front surface 206F of the semi-cured light-transmissive layer 206. In some embodiments, the composite packaging film 200 further includes a first carrier plate 202. Figure 4 Referring to FIGS. 1 and 2, in an embodiment, the back surface 206B of the semi-cured light-transmissive layer 206 of the composite packaging film 200 is pressed 312 towards the light emitting diode 104 of the light emitting structure 100 (as shown in FIG. 3), so that the light emitting diode 104 is embedded in the semi-cured light-transmissive layer 206 and corresponds to the position of the first reflective layer 208 respectively (as shown in FIG. 4).

[0061] Figure 5 Figure 6 Figure 5 Figure 6 ​​​​​In some embodiments, the lamination 312 can use vacuum lamination or other suitable lamination fabrication processes. In some embodiments, the lamination 312 is performed under a pressure of 0.05 MPa to 1 MPa (e.g., 0.2 MPa) for 2 minutes to 5 minutes (e.g., 3 minutes).

[0062] With continued reference to Figure 6 In one embodiment, a heating fabrication process 320 is performed on the composite encapsulation film 200 after lamination to cure the semi-cured light transmissible layer 206 to transform into a cured light transmissible layer 206'. In some embodiments, the heating fabrication process 320 can be performed at a temperature of 130 °C to 170 °C (e.g., 140 °C, 150 °C, or 160 °C) for 0.5 hours to 5 hours (e.g., 3 hours). Here, "curing" means that the semi-cured light transmissible layer 206 is transformed from a semi-cured state to a cured state due to heating. In one embodiment, performing the heating fabrication process 320 can also include curing the first reflective layer 208, in other words, in embodiments where the first reflective layer 208 is in a semi-cured state, the heating fabrication process 320 transforms the first reflective layer 208 from a semi-cured state to a cured state. It should be appreciated that the heating fabrication process 320 does not substantially affect the light extraction efficiency and reliability of the light emitting diodes 104.

[0063] Figure 7A FIG. 3B is a top view schematic diagram of a light emitting device 300 according to some embodiments of the present disclosure. Figure 7B FIG. 3C is a cross-sectional view schematic diagram of the light emitting device 300 of FIG. 3B along the reference cross-sectional plane A-A according to some embodiments of the present disclosure. Figure 7A FIG. 3C is a cross-sectional view schematic diagram of the light emitting device 300 of FIG. 3B along the reference cross-sectional plane A-A according to some embodiments of the present disclosure. In one embodiment, the first carrier substrate 202 is removed, as previously described, because the first carrier substrate 202 includes a release mold, and thus is easily peeled off from the surface of the first reflective layer 208.

[0064] With reference to Figure 7A In FIG. 3A, 20 light emitting diodes 104 are arranged in an array on the substrate 102, and the first reflective layer 208 is also arranged above the light emitting diodes 104 in the same number and array, but the present disclosure is not limited thereto. In other embodiments, the light emitting diodes 104 can be arranged in any number and in any array on the substrate 102 according to design requirements, and the first reflective layer 208 is arranged above the light emitting diodes 104 in the same number and array. It should be noted that although the first reflective layer 208 is illustrated as a circle in FIG. 3A, the present disclosure is not limited thereto, and in other embodiments, the first reflective layer 208 can be a square, a polygon, or any suitable shape. Figure 7A

[0065] With reference to Figure 7B ​In some embodiments, a portion of the light emitted by the light-emitting diode 104 is emitted through the first reflective layer 208, while another portion is reflected by the first reflective layer 208 into the cured light-transmitting layer 206', as shown by the light path L1. This can reduce the upward light emission of the light-emitting diode 104 and increase the distance that the light travels in the cured light-transmitting layer 206', thereby improving the surface light uniformity of the light-emitting device 300.

[0066] In an embodiment of the present invention, the semi-cured light-transmitting layer 206 and the first reflective layer 208 are laminated to the light-emitting structure 100 in the form of a composite packaging film 200. This allows for simultaneous installation of the semi-cured light-transmitting layer 206 and the first reflective layer 208, simplifying the manufacturing process and shortening the production time, thereby improving productivity and reducing costs. Furthermore, due to the low fluidity of the semi-cured light-transmitting layer 206 and the first reflective layer 208, the light-emitting device 300 does not require additional retaining walls around the light-emitting diode 104, simplifying the manufacturing process and reducing costs. Furthermore, the use of the composite packaging film 200 provided by the present invention avoids the high rate of encapsulant rejection associated with existing LED packaging technologies, thereby reducing costs.

[0067] The following describes some variations of the embodiments. In different drawings and embodiments described, the same or similar reference numerals are used to designate the same or similar components.

[0068] Figure 8A and Figures 8B to 12 2 is a schematic cross-sectional view of another light emitting device 400 at various stages of manufacture using a composite packaging film 220 / 220' having a second reflective layer 228 according to other embodiments of the present invention. It should be noted that the features of the various embodiments may be mixed and matched as long as they do not violate the spirit of the present invention or conflict with each other. It should be understood that additional embodiments of the method may be provided in the following examples: Figures 8A to 12 Additional operations are provided before, during, and after the steps shown, and some of the steps described below may be replaced or deleted in additional embodiments of the method. The order of the steps / processes is not limited and may be interchanged.

[0069] In some embodiments, Figure 8A The production process continues in Figure 4 After the manufacturing process, but before the composite packaging film 220 and the light emitting structure 100 are pressed together 318 ( Figure 11 ) before. Reference Figure 8A In one embodiment, a second carrier 222 is provided, and a second reflective layer 228 is formed on the second carrier 222 , wherein the second reflective layer 228 has a plurality of openings 224 corresponding to the first reflective layer 208 .

[0070] In some embodiments, the second carrier plate 222 may include a release film having an anti-sticking property that prevents the release film from adhering to the second reflective layer 228, and vice versa. This anti-sticking property helps to heat the second reflective layer 228 (for example, Figure 11 After the second carrier 222 is cured by the heating process 320, it is convenient to remove the second carrier 222.

[0071] In some embodiments, as described above, the first reflective layer 208 can reflect the upward light emitted by the light emitting diode 104, while the second reflective layer 228 can reflect the side light emitted by the light emitting diode 104, thereby improving the surface light uniformity of the light emitting device. This part will be discussed later with reference to FIG. Figure 13 Provide detailed explanation.

[0072] In one embodiment, the material, thickness, and reflectivity of the second reflective layer 228 to the wavelength of the light emitting diode 104 can be referred to Figure 2 For the sake of brevity, the first reflective layer 208 will not be described in detail here. In one embodiment, the second reflective layer 228 may be in a cured state or a semi-cured state. In some embodiments, the semi-cured second reflective layer 228 has better adhesion to the semi-cured light-transmissive layer 206, but using the cured second reflective layer 228 has lower costs.

[0073] In some embodiments, the thickness of the second reflective layer 228 is in a range of 40 μm to 80 μm (e.g., 50 μm), but the present invention is not limited thereto. Generally speaking, a thicker second reflective layer 228 has a better reflective effect, and a thinner second reflective layer 228 can better control the light emitted by the LED 104.

[0074] In some embodiments, as Figure 8A As shown, the second reflective layer 228 has a plurality of openings 224, and the number and arrangement of the openings 224 on the second carrier 222 are the same as the number and arrangement of the first reflective layer 208 after the first carrier 202 is flipped over. Therefore, the number and arrangement of the openings 224 are also the same as the number and arrangement of the light-emitting diodes 104. In some embodiments, each opening 224 has a width in the range of 2.5 cm to 4.5 cm (e.g., 3 cm), and the spacing between the openings 224 is in the range of 4 mm to 8 mm (e.g., 6 mm). However, the present invention is not limited thereto. As long as the composite packaging film 220 and the light-emitting structure 100 are subsequently pressed together 318 ( Figure 11 ), the light emitting diode 104 can be buried in the semi-cured light-transmitting layer 206.

[0075] In some embodiments, the opening 224 may be circular, square, polygonal, or any other suitable shape in a top view. Figure 7AThe pattern of the first reflective layer 208 can be complementary to the pattern of the second reflective layer 228 in some embodiments. For example, in an embodiment where the first reflective layer 208 is circular, the second reflective layer 228 is then patterned with corresponding circular openings 224.

[0076] In some embodiments, the method of forming the second reflective layer 228 can include first applying a second reflective layer material on the second carrier 222, and then removing portions of the second reflective layer by punching holes to form the second reflective layer 228 with a plurality of openings 224 after baking and curing. In some embodiments, the second reflective layer 228 with a plurality of openings 224 can be formed by a mold in advance and then placed on the second carrier 222.

[0077] Continuing to refer to Figure 8A In an embodiment, the second reflective layer 228 is laminated 314 toward the back surface 206B of the semi-cured light transmittable layer 206 with the openings 224 individually corresponding to the first reflective layer 208 to form the composite encapsulating film 220 as shown in Figure 9A In some embodiments, the lamination 314 can be performed with the same or different process conditions as the lamination 310 described in Figure 3

[0078] Figure 9A The composite encapsulating film 220 is similar to the composite encapsulating film 200 as shown in Figure 4 except that the composite encapsulating film 220 can further include the second reflective layer 228 disposed on the back surface 206B of the semi-cured light transmittable layer 206. In some embodiments, the composite encapsulating film 220 can include the second carrier 222. In some embodiments, the front surface 228F of the second reflective layer 228 is flush with the back surface 206B of the semi-cured light transmittable layer 206.

[0079] In other embodiments, as shown in Figure 8B the step of laminating the second reflective layer 228 toward the back surface 206B of the semi-cured light transmittable layer 206 can include providing another additional semi-cured light transmittable layer 226 with a first surface 226F and a second surface 226B opposite to each other, i.e., the first surface 226F as the front surface and the second surface 226B as the back surface, laminating the second reflective layer 228 to the second surface 226B of the another additional semi-cured light transmittable layer 226 first, and then laminating the first surface 226F of the another additional semi-cured light transmittable layer 226 toward the back surface 206B of the semi-cured light transmittable layer 206 to obtain the composite encapsulating film 220' as shown in Figure 9B In some embodiments, the lamination 316 can be performed with the same or different process conditions as the lamination 310 described in Figure 3 ​The fabrication process conditions of the described lamination 310 are performed.

[0080] Figure 9B The composite encapsulation film 220' is similar to Figure 9A the composite encapsulation film 220, with the difference that the composite encapsulation film 220' further comprises another additional semi-cured light-transmissive layer 226 between the semi-cured light-transmissive layer 206 and the second reflective layer 228. In some embodiments, the material of the another additional semi-cured light-transmissive layer 226 is different from that of the semi-cured light-transmissive layer 206, thus there is a distinct interface between the material of the another additional semi-cured light-transmissive layer 226 and the semi-cured light-transmissive layer 206. In other embodiments, the material of the another additional semi-cured light-transmissive layer 226 is the same as that of the semi-cured light-transmissive layer 206, thus there is no distinct interface between the material of the another additional semi-cured light-transmissive layer 226 and the semi-cured light-transmissive layer 206, which is a continuous structure (not shown).

[0081] In some embodiments, the another additional semi-cured light-transmissive layer 226 is used to bond the semi-cured light-transmissive layer 206. In some embodiments, the material, thickness and forming method of the another additional semi-cured light-transmissive layer 226 can refer to those of the semi-cured light-transmissive layer 206. Figure 3 The described semi-cured light-transmissive layer 206 is not repeated here for brevity. In some embodiments, the another additional semi-cured light-transmissive layer 226 and the semi-cured light-transmissive layer 206 can have a brightening effect due to the difference in materials.

[0082] Figure 10 Following Figure 9A or Figure 9B , in an embodiment, the second carrier 222 is removed. As mentioned previously, since the second carrier 222 comprises a release mold, it is easy to tear off from the surface of the second reflective layer 228.

[0083] Referring next to Figure 11 and Figure 12 , in an embodiment, the openings 224 of the second reflective layer 228 of the composite encapsulation film 220 are respectively aligned with the light-emitting diodes 104 of the light-emitting structure 100, and the back surface 206B of the semi-cured light-transmissive layer 206 exposed by the openings 224 is pressed 318 (as shown in Figure 11 ) toward the light-emitting diodes 104, so that the light-emitting diodes 104 are embedded in the semi-cured light-transmissive layer 206 and surrounded by the second reflective layer 228, and the position above each light-emitting diode 104 respectively corresponds to that of the first reflective layer 208 (as shown in Figure 12 ).

[0084] Continuing to refer to Figure 12In one embodiment, a heating fabrication process 322 is performed on the composite encapsulation film 220 to cure the semi-cured light transmissive layer 206 to transform into a cured light transmissive layer 206'. In one embodiment, the heating fabrication process 324 can further include curing another additional semi-cured light transmissive layer 226. Here, "curing" means that the semi-cured light transmissive layer 206 and / or the another additional semi-cured light transmissive layer 226 is transformed from a semi-cured state to a cured state due to heating. In some embodiments, the fabrication process conditions of the heating fabrication process 322 can be performed with reference to the fabrication process conditions of the heating fabrication process 320, both of which can be the same or different. Figure 6

[0085] In one embodiment, the heating fabrication process 322 further includes curing the first reflective layer 208 and / or the second reflective layer 228, in other words, transforming the first reflective layer 208 and / or the second reflective layer 228 from a semi-cured state to a cured state.

[0086] Referring to Figure 13 In one embodiment, the first carrier substrate 202 is removed. In some embodiments, the upward light emission of the light emitting diodes 104 is reflected by the first reflective layer 208 above the light emitting diodes 104 to the cured light transmissive layer 206', as shown by the light path LI, which can reduce the brightness of the upward emission of the light emitting diodes 104 to improve the surface light emission uniformity of the light emitting device 400. In some embodiments, the side light emission of the light emitting diodes 104 is reflected upward by the second reflective layer 228 between the light emitting diodes 104, as shown by the light path L2, which can further improve the surface light emission uniformity of the light emitting device 400.

[0087] Figures 14 to 18 FIGS. 13A to 13C are cross-sectional schematic views illustrating a light emitting device 400 using a composite encapsulation film 240 at various fabrication stages according to yet other embodiments of the present application.

[0088] In the present embodiment, Figures 14 to 18 the fabrication process of Figure 8A is performed after the fabrication process of Figure 8A the pressing step of Figure 14 is performed, the difference is that the semi-cured light transmissive layer 206 is filled into the openings 224 of the second reflective layer 228 when the pressing step of Figure 14 is performed, so that the second reflective layer 228 is embedded in the semi-cured light transmissive layer 206, which can be beneficial for the light and thin product. As shown in

[0089] Referring to Figure 15The second carrier 222 is removed to expose the back surface 206B of the semi-cured light-transmissive layer 206 and the second reflective layer 228.

[0090] Referring to Figure 16 In some embodiments, the back surface 206B of the exposed semi-cured light-transmissive layer 206 of the composite encapsulation film 240 is pressed 319 toward the light-emitting diode 104. In some embodiments, the fabrication process conditions of the pressing 319 can be performed with reference to the fabrication process conditions of the pressing 312. Figure 5 The fabrication process conditions of the pressing 319 can be the same as or different from the fabrication process conditions of the pressing 312.

[0091] Referring to Figure 17 In the present embodiment, a heating fabrication process 324 is performed on the composite encapsulation film 240 to cure the semi-cured light-transmissive layer 206 to transform into a cured light-transmissive layer 206'. Here, "cure" means that the semi-cured light-transmissive layer 206 is transformed from a semi-cured state to a cured state due to heating. In some embodiments, the fabrication process conditions of the heating fabrication process 324 can be performed with reference to the fabrication process conditions of the heating fabrication process 320. Figure 6 After that, the first carrier 202 is removed to obtain the light-emitting device 400 as shown in Figure 18

[0092] The present disclosure provides a composite encapsulation film and a fabrication process method of a light-emitting device using the same. The semi-cured light-transmissive layer and the first reflective layer provided by the present disclosure are pressed with a light-emitting structure in the form of a composite encapsulation film, and the setting of the encapsulation film (e.g., the semi-cured light-transmissive layer) and the reflective layer (e.g., the first reflective layer) can be completed at the same time, which can simplify the process and shorten the fabrication process time, thereby improving the yield and reducing the cost. In addition, since the flowability of the composite encapsulation film provided by the present disclosure is low, it is not necessary to additionally set a barrier wall around the light-emitting diode, which can simplify the process and reduce the cost. Furthermore, using the composite encapsulation film provided by the present disclosure can avoid the problem of high material rejection rate of the encapsulation glue in the existing LED encapsulation technology, thereby reducing the cost.

[0093] The components of the above-described embodiments are summarized in order to enable a person of ordinary skill in the art to more readily understand the concepts of the present embodiments. It will be understood by those of ordinary skill in the art that they can design or modify other fabrication processes and structures based on the embodiments of the present disclosure to achieve the same purposes and / or advantages as the embodiments introduced herein. Those of ordinary skill in the art should also understand that such equivalent fabrication processes and structures do not deviate from the spirit and scope of the present disclosure, and they can make various changes, substitutions and replacements without departing from the spirit and scope of the present disclosure.​

Claims

1. A method for manufacturing a light emitting device, comprising: providing a substrate; providing a light emitting structure, wherein the light emitting structure comprises a plurality of solid state light sources disposed on the substrate; providing a composite encapsulation film for encapsulating the light emitting structure, wherein the composite encapsulation film comprises: a semi-cured light transmissive layer having a front surface and a back surface; and a plurality of first reflective layers spaced apart on the front surface of the semi-cured light transmissive layer; laminating the back surface of the semi-cured light transmissive layer of the composite encapsulation film towards the solid state light sources of the light emitting structure, so that the solid state light sources are embedded in the semi-cured light transmissive layer and respectively correspond to positions of the first reflective layers; and performing a heating fabrication process on the composite encapsulation film to cure the semi-cured light transmissive layer.

2. The method of claim 1, wherein the composite encapsulation film is formed by: providing a first carrier substrate; spaced apart the first reflective layers on the first carrier substrate, and the first reflective layers are in a cured state or a semi-cured state; and inverting the first carrier substrate to laminate the first reflective layers towards the front surface of the semi-cured light transmissive layer, so that the first reflective layers are in direct contact with the semi-cured light transmissive layer.

3. The method of fabricating a light emitting device as set forth in claim 1, wherein performing the heating fabrication process comprises: curing the first reflective layers.

4. The method of claim 2, further comprising removing the first carrier substrate.

5. A method for manufacturing a light emitting device, comprising: providing a substrate; providing a light emitting structure, wherein the light emitting structure comprises a plurality of solid state light sources disposed on the substrate; providing a composite encapsulation film for encapsulating the light emitting structure, wherein the composite encapsulation film comprises: a semi-cured light transmissive layer having a front surface and a back surface; a plurality of first reflective layers spaced apart on the front surface of the semi-cured light transmissive layer; and a second reflective layer on the back surface of the semi-cured light transmissive layer, wherein the second reflective layer has a plurality of openings to expose a portion of the back surface of the semi-cured light transmissive layer, and the openings respectively correspond to positions of the first reflective layers; aligning the openings of the second reflective layer of the composite encapsulation film with the solid state light sources of the light emitting structure, laminating the exposed back surface of the semi-cured light transmissive layer towards the solid state light sources, so that the solid state light sources are embedded in the semi-cured light transmissive layer and respectively correspond to positions of the first reflective layers; and performing a heating fabrication process on the composite encapsulation film to cure the semi-cured light transmissive layer.

6. The method of claim 5, wherein the composite encapsulation film is formed by: providing a first carrier substrate; spaced apart the first reflective layers on the first carrier substrate, and the first reflective layers are in a cured state or a semi-cured state; inverting the first carrier substrate to laminate the first reflective layers towards the front surface of the semi-cured light transmissive layer, so that the first reflective layers are in direct contact with the semi-cured light transmissive layer; providing a second carrier substrate; forming the second reflective layer on the second carrier substrate, wherein the second reflective layer has the openings, and the second reflective layer is in a cured state or a semi-cured state; and The second reflective layer is laminated toward the back surface of the semi-cured light transmittable layer, wherein the openings of the second reflective layer correspond to the first reflective layers respectively.

7. The method of producing a light emitting device according to Claim 6, wherein the step of pressing the second reflective layer toward the back surface of the semi-cured light-transmissive layer comprises: The semi-cured light transmittable layer fills the openings of the second reflective layer.

8. The method of claim 6, wherein the step of laminating the second reflective layer toward the back surface of the semi-cured light transmittable layer comprises: providing another additional semi-cured light transmittable layer having opposite first and second surfaces; laminating the second reflective layer to the second surface of the another additional semi-cured light transmittable layer; and laminating the first surface of the another additional semi-cured light transmittable layer toward the back surface of the semi-cured light transmittable layer.

9. The method of producing a light emitting device as recited in claim 8, wherein performing the heating fabrication process comprises: curing the another additional semi-cured light transmittable layer, the first reflective layers, and the second reflective layer.

10. The method of claim 6, further comprising removing the first carrier and the second carrier.

11. A composite encapsulation film for encapsulating a light emitting structure, wherein the composite encapsulation film comprises: a semi-cured light transmittable layer having a front surface and a back surface; and a plurality of first reflective layers spaced apart on the front surface of the semi-cured light transmittable layer, wherein the first reflective layers are in direct contact with the semi-cured light transmittable layer.

12. The composite encapsulation film of claim 11, wherein the semi-cured light transmittable layer is a silicone or an epoxy resin.

13. The composite encapsulation film of claim 11, wherein the first reflective layers are a polymer material doped with reflective particles, and the first reflective layers are in a cured or semi-cured state.

14. The composite packaging film of claim 11, further comprising: a second reflective layer disposed on the back surface of the semi-cured light transmittable layer, wherein the second reflective layer has a plurality of openings corresponding to the positions of the first reflective layers respectively.

15. The composite encapsulation film of claim 14, wherein the second reflective layer is a polymer material doped with reflective particles, and the second reflective layer is in a cured or semi-cured state.

16. The composite encapsulation film of claim 14, wherein the second reflective layer is embedded in the semi-cured light transmittable layer.

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