Light emitting device package with reflective side cladding

Abstract

A light emitting device is disclosed that includes a semiconductor structure having an active region disposed between an n-type layer and a p-type layer; a wavelength converter formed over the semiconductor structure; an insulating side wrap formed around the semiconductor structure; and a reflective side wrap formed around the wavelength converter, over the insulating side wrap, the reflective side wrap having a top surface that is flush with a top surface of the wavelength converter.

Description

[0001] Cross-references to related applications This application claims the benefit of U.S. Provisional Application No. 62 / 368067, filed July 28, 2016; European Patent Application No. 16190895.9, filed September 27, 2016; and U.S. Non-Provisional Application No. 15 / 661196, filed July 27, 2017, which are incorporated herein by reference as if fully illustrated. Technical Field

[0002] This disclosure relates generally to light-emitting devices, and more specifically, to light-emitting device packages having a reflective side coating. Background Technology

[0003] Light-emitting diodes (“LEDs”) are commonly used as light sources in a variety of applications. The main functional part of an LED can be a semiconductor chip comprising two injection layers of opposite conductivity types (p-type and n-type) and a light-emitting active layer where radiative recombination of charge carriers occurs. The semiconductor chip is typically placed in a package that, in addition to protecting the semiconductor chip from vibration and thermal damage, provides an electrical connection between the LED chip and the external world.

[0004] LED packaging plays a crucial role in removing the heat generated during LED device operation. Poor heat dissipation can place LED devices under excessive thermal stress, severely impacting their performance. Excessive thermal stress can shorten LED device lifespan and lead to various types of failures, such as color drift, decreased transparency of lenses found in LED devices, and reduced quantum efficiency. Since a significant portion of the power supplied to an LED is converted into heat, this heat must be efficiently dissipated into the environment to ensure reliable performance.

[0005] Therefore, there is a need for improved LED packaging designs that provide efficient heat dissipation. Summary of the Invention

[0006] This disclosure addresses this need. According to an aspect of this disclosure, a light-emitting device is disclosed, comprising a semiconductor structure having an active region disposed between an n-type layer and a p-type layer; a wavelength converter formed above the semiconductor structure; an insulating side cladding layer formed around the semiconductor structure; and a reflective side cladding layer formed around the wavelength converter and above the insulating side cladding layer, the reflective side cladding layer having a top surface flush with the top surface of the wavelength converter. Attached Figure Description

[0007] The accompanying drawings described below are for illustrative purposes only. The drawings are not intended to limit the scope of this disclosure. The same reference numerals shown in the drawings identify the same components in various embodiments.

[0008] Figure 1 This is a cross-sectional view of an example of a light-emitting device according to aspects of this disclosure; Figure 2 Based on the aspects of this disclosure Figure 1 A cross-sectional view of a light-emitting device, illustrating the flow of heat emanating from the light-emitting device; Figure 3A This is a flowchart illustrating an example of a process for manufacturing a light-emitting device according to aspects of this disclosure; Figure 3B The illustrations are based on aspects of this disclosure. Figure 3A A schematic diagram of the steps in the process; Figure 3C The illustrations are based on aspects of this disclosure. Figure 3A A schematic diagram of the steps in the process; Figure 3D The illustrations are based on aspects of this disclosure. Figure 3A A schematic diagram of the steps in the process; Figure 3E The illustrations are based on aspects of this disclosure. Figure 3A A schematic diagram of the steps in the process; Figure 4A This is a schematic cross-sectional view of an example of a light-emitting device according to aspects of this disclosure; Figure 4B Based on the aspects of this disclosure Figure 4A A schematic top view of the illuminated structure; Figure 4C Based on the aspects of this disclosure Figure 4A A schematic top view of the light-emitting device; Figure 4D Based on the aspects of this disclosure Figure 4A A schematic top view of the light-emitting device; Figure 5 Based on the aspects of this disclosure Figure 4A A cross-sectional view of a light-emitting device, illustrating the flow of heat emanating from the light-emitting device; Figure 6A This is a flowchart illustrating an example of a process for manufacturing a light-emitting device according to aspects of this disclosure; Figure 6B The illustrations are based on aspects of this disclosure. Figure 6A A schematic diagram of the steps in the process; Figure 6C The illustrations are based on aspects of this disclosure. Figure 6A A schematic diagram of the steps in the process; Figure 6D The illustrations are based on aspects of this disclosure. Figure 6AA schematic diagram of the steps in the process; Figure 6E The illustrations are based on aspects of this disclosure. Figure 6A A schematic diagram of the steps in the process; Figure 6F The illustrations are based on aspects of this disclosure. Figure 6A A schematic diagram of the steps in the process; Figure 6G The illustrations are based on aspects of this disclosure. Figure 6A A schematic diagram of the steps in the process; Figure 6H The illustrations are based on aspects of this disclosure. Figure 6A A schematic diagram of the steps in the process; Figure 6I The illustrations are based on aspects of this disclosure. Figure 6A A diagram illustrating the steps in the process; and Figure 6J The illustrations are based on aspects of this disclosure. Figure 6A A diagram illustrating the steps in the process. Detailed Implementation

[0009] According to an aspect of this disclosure, a light-emitting device is disclosed, including a light-emitting semiconductor structure and a wavelength converter formed above the semiconductor structure. The semiconductor structure is at least partially surrounded by an insulating side cladding. The wavelength converter is at least partially surrounded by a reflective side cladding formed on top of the insulating side cladding. Because the reflective side cladding is in thermal contact with the wavelength converter, it provides an additional path for transferring heat from the wavelength converter to the surrounding environment.

[0010] According to aspects of this disclosure, a reflective side coating can help protect the wavelength converter from overheating. Overheating can typically cause color drift in the wavelength converter and shorten its lifespan. By efficiently dissipating heat away from the wavelength converter, the reflective side coating can extend the wavelength converter's lifespan and reduce its likelihood of failure.

[0011] According to aspects of this disclosure, the insulating side capping prevents the reflective side capping from short-circuiting the semiconductor structure. The insulating side capping can be formed of a dielectric material with low thermal conductivity. The reflective side capping can be conductive and can have high thermal conductivity. By stacking the reflective side capping on the insulating side capping, a composite capping structure is formed, which serves as a heat dissipation surface for the wavelength converter while also providing electrical insulation for the semiconductor structure of the light-emitting device.

[0012] According to aspects of this disclosure, insulating and reflective sidecoats can be applied using a scalable and cost-effective process. The first sidecoat can be applied by placing a first template around an LED die comprising a semiconductor structure and a wavelength converter. The template can define a first trench around the LED die, the trench being filled with an insulating material. After the insulating material is applied to the first trench, the first template is removed. When the first template is removed, the insulating material is no longer contained within the first trench. As a result, the insulating material is adsorbed onto the wall of the LED die by capillary action to form the insulating sidecoat.

[0013] After at least partially forming the insulating sidewall, a second template is placed on the LED die. The second template defines a second trench around the LED die, which is filled with a reflective material. After the reflective material is applied to the second trench, the second template is removed. When the second template is removed, the reflective material is no longer contained in the second trench. As a result, the reflective material is attracted to the wall of the LED die by capillary action.

[0014] According to aspects of this disclosure, an insulating material can be applied in sufficient quantity to substantially cover the semiconductor structure of the LED die when the insulating material is attracted to the wall of the LED die. Furthermore, a reflective material can be applied in sufficient quantity to substantially cover the wall of the LED die's wavelength converter when the reflective material is attracted to the wall of the LED die by capillary action, without overflowing onto the top of the wavelength converter.

[0015] According to aspects of this disclosure, the first template may differ from the second template. For example, the second trench defined by the second template may be deeper than the first trench. Furthermore, the second trench may be deeper than the height of the LED die to allow reflective material to settle to the height of the LED die when the second template is removed. In other words, the first trench may be sized to allow the application of insulating material in an amount sufficient to cover the sides of the semiconductor structure of the LED die when the first template is removed and the insulating material settles. Similarly, the second trench may be sized to allow the application of reflective material in an amount sufficient to cover the sides of the wavelength converter of the LED die when the second template is removed and the reflective material settles.

[0016] According to an aspect of this disclosure, a light-emitting device is disclosed, comprising: a semiconductor structure having an active region disposed between an n-type layer and a p-type layer; a wavelength converter formed above the semiconductor structure; an insulating side cladding layer formed around the semiconductor structure; and a reflective side cladding layer formed around the wavelength converter and above the insulating side cladding layer, the reflective side cladding layer having a top surface flush with the top surface of the wavelength converter.

[0017] According to an aspect of this disclosure, a light-emitting device is disclosed, comprising: an LED die including a semiconductor structure and a wavelength converter formed over the semiconductor structure; an insulating side cladding formed around the LED die, the insulating side cladding including a first adhesive material filled with reflective particles; and a reflective side cladding formed around the LED die and over the insulating side cladding, the reflective side cladding including a second adhesive material filled with metal powder, the reflective side cladding being thermally coupled to the wavelength converter, and the reflective side cladding having a top surface flush with the top surface of the wavelength converter.

[0018] According to an aspect of this disclosure, a method for manufacturing a light-emitting diode (LED) package includes: placing an LED die on a support, the LED die including: a semiconductor structure having an active region disposed between an n-type layer and a p-type layer; and a wavelength converter formed above the semiconductor structure; forming an insulating side cladding layer around the semiconductor structure; and forming a reflective side cladding layer around the wavelength converter and above the insulating side cladding layer, the reflective side cladding layer having a top surface flush with the top surface of the wavelength converter.

[0019] Examples of different LED packages will now be described more fully with reference to the accompanying drawings. These examples are not mutually exclusive, and features found in one example may be combined with features found in one or more other examples to achieve additional implementations. Therefore, it will be understood that the examples shown in the drawings are provided for illustrative purposes only and are not intended to limit this disclosure in any way. The same reference numerals always refer to the same elements.

[0020] It will be understood that although the terms first, second, etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are used only to distinguish one element from another. For example, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element, without departing from the scope of the invention. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0021] It will be understood that when an element, such as a layer, region, or substrate, is referred to as being "on" or extending "to" another element, it may be directly on or directly extended to the other element, or there may be intermediate elements present. Conversely, when an element is referred to as being "directly on" or "directly extended" to another element, there are no intermediate elements present. It will also be understood that when an element is referred to as being "connected" or "coupled" to another element, it may be directly connected or coupled to the other element, or there may be intermediate elements present. Conversely, when an element is referred to as being "directly connected" or "directly coupled" to another element, there are no intermediate elements present. It will be understood that these terms are intended to include different orientations of elements, except for any orientation depicted in the figures.

[0022] This document may use relative terms such as “below” or “above” or “upper” or “lower” or “horizontal” or “vertical” to describe the relationship between one element, layer or region illustrated in the figures and another element, layer or region. It will be understood that these terms are intended to include different orientations of the device in addition to those depicted in the figures.

[0023] Figure 1 This is a cross-sectional view of an example of a chip-scale package (CSP) of a light-emitting device 100 according to aspects of this disclosure. As shown, the device 100 includes an LED die 102, the LED die 102 including a semiconductor structure 106 coupled to pads 104-1 and 104-2, a transparent substrate formed over the semiconductor structure 106, and a wavelength converter 110 formed over the transparent structure.

[0024] Figure 2 yes Figure 1 A cross-sectional view of device 100 illustrates heat dissipation from device 100 when it is mounted on a support such as a printed circuit board (PCB) 200. As shown, during normal operation of device 100, wavelength converter 110 generates heat (shown as dashed arrow lines), which travels downwards from wavelength converter 110, through transparent substrate 108, and out from pads 104-1 and 104-2 into PCB 200. Due to the low thermal conductivity of insulating side coating 112, very little heat escapes through insulating side coating 112. For example, silicone / TiO2 reflective side coating 112 has a thermal conductivity of 0.8 to 0.9 W / mK. Therefore, as the size of device 100 becomes smaller, additional heat dissipation paths are needed to dissipate the heat generated by wavelength converter 110 to prevent overheating of wavelength converter 110 and / or LED die 102.

[0025] Figure 3A It is based on aspects of this disclosure for manufacturing light-emitting devices (such as...) Figure 1The flowchart of process 300 for device 100. Combined with... Figure 3B -E describes process 300, Figure 3B -E is a cross-sectional view illustrating the different manufacturing stages of a light-emitting device.

[0026] In step 310, the LED die 102 is attached to the support member 304, such as... Figure 3B As shown. Support 304 may include tape and / or any other suitable type of support. In step 320, an overlay molding 308 is formed to cover the LED die 102, as shown. Figure 3C As shown. In step 330, the encapsulation molding is removed to expose the wavelength converter 110 of the LED die 102, as... Figure 3D As shown. In some implementations, wet abrasive blasting 312, such as microbead blasting (WMBB), can be used to remove excess mold material. As a result of abrasive blasting, a surface 316 can be formed on each of the wavelength converters 110, such as... Figure 3E As shown. In step 340, the LED chips 102 separate from each other and from the support member 304.

[0027] Wet abrasive blasting techniques, such as WMBB, may have narrow parameter windows for water pressure, bead size, and slurry mixture, which could make it difficult to provide a flat surface on the wavelength converter 110. In this regard, Figure 3E The effect on surface 316 is shown when these parameters are not precisely controlled. For example... Figure 3E As illustrated, when one or more microblasting parameters are not precisely controlled, surface 316 may become rough and uneven, which in turn may cause LED die 102 to produce a color that is different from its target specifications.

[0028] Figure 4A This is a cross-sectional view of an example of a chip-scale package (CSP) of a light-emitting device 400 according to aspects of the present disclosure. As shown, the device 400 includes an LED die 402, which is at least partially surrounded by an insulating-side cover 412 and a reflective-side cover 414. The reflective-side cover 414 is formed over the insulating-side cover 412, as shown.

[0029] LED die 402 includes a semiconductor structure 406 coupled to pads 404-1 and 404-2. LED die 402 also includes a transparent substrate 408 disposed between semiconductor structure 406 and wavelength converter 410. Although LED die 412 has a flip-chip configuration in this example, alternative implementations of LED die 412 with any other suitable type of configuration are possible.

[0030] Semiconductor structure 406 may be a semiconductor light source epitaxially grown on transparent substrate 408. Semiconductor structure 406 may include an active layer sandwiched between an n-type layer and a p-type layer. When a suitable voltage is applied to pads 404-1 and 404-2, charge carriers recombine in the active layer and thus emit light. In some implementations, semiconductor structure 406 may include additional circuitry, such as circuitry for transient voltage suppression.

[0031] The transparent substrate 408 can be a sapphire substrate. However, alternative implementations are possible, where any other suitable type of substrate is used instead. Although substrate 408 is transparent in this example, alternative implementations where substrate 408 is opaque are possible.

[0032] Wavelength converter 410 may include any suitable type of material arranged to change the frequency of light emitted by semiconductor structure 406. For example, wavelength converter 410 may include a phosphor coating or a ceramic phosphor plate. In operation, the wavelength converter can change blue light emitted by semiconductor structure 406 to white light.

[0033] The insulating side cap 412 may comprise any suitable type of dielectric material capable of electrically insulating the semiconductor structure 406 from the reflective side cap 414. In some implementations, the insulating side cap 412 may comprise an adhesive material filled with reflective particles. For example, the insulating side cap 412 may comprise a silicone resin mixed with TiO2 or a white solder mask. As another example, the insulating side cap 412 may comprise an epoxy resin mixed with TiO2 or a white solder mask. In some implementations, the insulating side cap 412 may substantially cover the sidewall of 406-1 of the semiconductor structure 406 to prevent the reflective side cap 414 from short-circuiting the semiconductor structure 406.

[0034] The reflective sidecoat 414 may comprise any suitable type of material capable of dissipating heat away from the wavelength converter 410. In some implementations, the reflective sidecoat may comprise a metal, such as silver. Additionally or alternatively, in some implementations, the reflective sidecoat 414 may comprise a binder material filled with metal powder. For example, the reflective sidecoat 414 may be formed of a silver paste material comprising a solvent, a binder, and additives that promote adhesion to the insulating sidecoat 412 and / or the wavelength converter 410.

[0035] In some implementations, the reflective cladding 414 can have a significantly higher thermal conductivity than the insulating cladding. For example, when the insulating cladding 412 is formed of TiO2-filled silicone resin, it can have a thermal conductivity of 0.8 to 0.9, while when the reflective cladding 414 is formed of silver, it can have a thermal conductivity of at least 200 W / mk. As discussed further below, the high thermal conductivity of the reflective cladding can help facilitate heat transfer from the wavelength converter 410.

[0036] In some implementations, the insulating side cladding 412 can be dielectric, while the reflective side cladding can be conductive. As a result, the insulating side cladding 412 can protect the semiconductor structure 406 from short circuits during manufacturing and prevent electromigration of the reflective side cladding material (e.g., silver) during reliability testing.

[0037] In some implementations, both the reflective side coating 414 and the insulating side coating 412 can reflect light from the sides of the LED die 402 to the top to improve light output. For example, when the reflective side coating 414 is at least partially formed of silver, it has a reflectivity of 95%. As another example, when the insulating side coating 412 is formed of TiO2-filled silicone resin, it can have a reflectivity of 90% to 94%.

[0038] In some implementations, the wavelength converter 410 may extend over the transparent substrate 408, thereby exposing a portion of the bottom surface 410-1 of the wavelength converter 410, as shown. As a result, the reflective side cladding 414 can contact both the bottom surface 410-1 and the side surface 410-2 of the wavelength converter. Arranging the wavelength converter 410 to extend over the transparent substrate 408 can thus increase the surface area of ​​the wavelength converter 410 available for contact with the reflective side cladding 414. This increased surface area in contact with the reflective side cladding 414 can, in turn, increase the rate at which heat can be transferred from the wavelength converter 410 to the side cladding 414.

[0039] In some implementations, the top surface 414-1 of the reflective cladding 414 can be flush with the top surface 410-3 of the wavelength converter 410, as shown in the figure. Arranging the wavelength converter 410 and the reflective cladding 414 in this manner prevents the reflective cladding 414 from blocking light emission from the top surface 410-3 of the wavelength converter. In other words, the way the reflective cladding 414 is coupled to the wavelength converter 410 maximizes the light-emitting surface of the device 400 while also providing sufficient thermal coupling between the reflective cladding 414 and the wavelength converter 410.

[0040] Figure 4B Based on the aspects of this disclosure Figure 4A A top view of device 400. As shown in the figure, in Figure 4B In the example, the reflective side coating 414 completely surrounds the wavelength converter 410. However, alternative implementations are possible in which the wavelength converter 410 is only partially surrounded by the reflective side coating 414.

[0041] Figure 4C yes Figure 4A A top view of device 400, with wavelength converter 410 removed to expose components beneath it. As shown, in Figure 4C In the example, the reflective side cladding 414 completely surrounds the transparent substrate 408. However, an alternative implementation is possible in which the wavelength converter 410 is only partially surrounded by the reflective side cladding 414.

[0042] Figure 4D Based on the aspects of this disclosure Figure 4A A top view of device 400. Figure 4D In this embodiment, the wavelength converter 410, the reflective side cap 414, and the transparent substrate 408 are removed to expose the insulating side cap 412 and the semiconductor structure 406 beneath them. As illustrated, in this example, the insulating side cap 412 completely surrounds the semiconductor structure 406. However, alternative implementations are possible where the semiconductor structure 406 is only partially surrounded by the insulating side cap 412.

[0043] Figure 5 yes Figure 4A A cross-sectional view of device 400 illustrates heat dissipation from device 400 when it is mounted on a support such as a printed circuit board (PCB) 500. As shown, heat generated by wavelength converter 410 (shown as dashed arrow lines) travels downwards from wavelength converter 410, through transparent substrate 408, and out through pads 404-1 and 404-2 into PCB 500. Heat also travels out from wavelength converter 410 via reflective side cladding 414. In some respects, the additional path of heat exit provided by reflective side cladding 414 allows device 400 to be manufactured smaller without overheating.

[0044] Figure 6A It is based on aspects of this disclosure for manufacturing light-emitting devices (such as...) Figure 4A The flowchart of process 600 for device 400. Combined with... Figure 6B -J describes process 600, Figure 6B -J is a cross-sectional view illustrating the different manufacturing stages of the light-emitting device.

[0045] In step 605, multiple LED chips 402 are attached to the support member 604, such as... Figure 6B As shown. Support 604 may include tape and / or any other suitable type of support.

[0046] In step 610, the template 608 is placed on the LED chip 402, as follows: Figure 6C As shown. Template 608 may be a stepped template defining a groove 609 around each LED die 402. According to aspects of this disclosure, template 608 may include any suitable type of template, such as, for example, an electroforming template or a mesh template.

[0047] In step 615, insulating material 612 is spread on template 608 and deposited into trench 609, such as Figure 6C As shown. A scraper 614 can be used to deposit the insulating material 612. For example... Figure 6D As shown, when the application of insulating material 612 is completed, trench 609 becomes filled with insulating material 612. In some implementations, insulating material 612 may include an adhesive material filled with reflective particles. For example, insulating material 612 may include silicone resin mixed with TiO2 or a white solder mask. As another example, insulating material 612 may include epoxy resin mixed with TiO2 or a white solder mask.

[0048] In step 620, remove template 608, as follows: Figure 6E As shown. After removing the template 608, the insulating material 612 is drawn to the edge of the LED die 402 by capillary action to at least cover the sides of its semiconductor structure 406, as shown. Figure 6F As shown.

[0049] In step 625, the insulating material 612 is cured to form an insulating side cladding 412. In some implementations, the insulating material 612 can be partially cured by heating to 100-150 degrees Celsius. Partially cured insulating material 612 allows it to interact with reflective material 628 (…). Figure 6G (As shown in the figure) it is bonded when the reflective material 628 is subsequently deposited and cured.

[0050] In step 630, the template 624 is placed on the LED chip 402, as follows: Figure 6G As shown. Template 624 may be a stepped template defining a groove 626 around each LED die 402. According to aspects of this disclosure, template 624 may include any suitable type of template, such as, for example, a 3D electroforming template or a mesh template.

[0051] In step 635, reflective material 628 is spread on template 624 and deposited into trench 626. For example... Figure 6D As shown, reflective material 628 can be deposited into trench 626 using scraper 631. As a result, trench 626 can become filled with reflective material 628, such as... Figure 6HAs shown. In some implementations, the reflective material 628 may include a binder material filled with metal powder. For example, the reflective material 628 may include a silver paste comprising a solvent, a binder, and additives that promote adhesion to the insulating material 612 and / or the wavelength converter 410 of the LED die 402.

[0052] In step 640, remove template 624, as follows: Figure 6I As shown. After removing the template, the reflective material 628 is drawn to the edge of the LED die 402 via capillary action to at least cover the sides of its transparent substrate 408 and the wavelength converter 410. Figure 6J As shown in the figure, after the reflective material 628 is attracted to the edge of the LED chip 402, it can form a surface flush with the top surface of the LED chip 402.

[0053] In step 645, the reflective material 628 is cured to form a reflective side coating 414. In some implementations, the reflective material 628 may be sintered to burn off any solvent and form a solid reflective side coating 414. In examples where the reflective material 628 comprises a silver paste reflective material, it may have a low sintering temperature of about 220°C and a short sintering time of about 2 hours. Additionally or alternatively, in some implementations, additives retained in the solid reflective side coating 414 promote adhesion between the reflective side coating 414 and the transparent substrate 408 or the wavelength converter 410. Additionally or alternatively, in examples where the insulating material 612 is only partially cured in step 625, the curing of the insulating material may be completed in step 645. In some implementations, simultaneous curing of the insulating material 612 and the reflective material 628 may result in a stronger adhesion between the insulating side coating 412 and the reflective side coating 414.

[0054] In step 650, the LED chips 402 separate from each other and / or from the support 604. For example... Figure 6J As shown in the diagram, each LED can be individually mounted along line 638 from support member 604.

[0055] In some implementations, trench 609 may be sized to receive a sufficient amount of insulating material 612 to cover the sides of the semiconductor structure of LED die 402. Alternatively, trench 626 may be sized to receive a sufficient amount of insulating material 612 to cover the remainder of LED die 402 without overflowing onto the top surface of wavelength converter 410. Alternatively, trench 626 may be deeper than trench 609. Alternatively, either trench 609 or trench 626 may be deeper than the height of LED die 402.

[0056] Figure 1-6JProvided by way of example only. At least some of the elements discussed with respect to these figures may be arranged, combined and / or omitted entirely in a different order. It will be understood that the examples described herein, and terms expressed as “such as,” “e.g.,” “including,” “in some aspects,” “in some implementations,” etc., should not be construed as limiting the disclosed subject matter to the specific examples.

[0057] The present invention has been described in detail, and those skilled in the art will understand that modifications can be made to the invention without departing from the spirit of the inventive concept described herein. Therefore, the scope of the invention is not intended to be limited to the specific embodiments illustrated and described.

Claims

1. A light-emitting device, comprising: A substrate, comprising a top surface, a bottom surface, and a side surface; A semiconductor structure including a top surface, a bottom surface, and a side surface, wherein the top surface of the semiconductor structure is on the bottom surface of the substrate; A wavelength conversion element includes a top surface, a bottom surface, and a side surface, wherein the bottom surface of the wavelength conversion element is on the top surface of the substrate; An insulating side cladding layer surrounds the side of the semiconductor structure; and A reflective side cladding includes a top surface, a bottom surface, and a side surface, the side surface of the reflective side cladding surrounding and contacting the side surface of the wavelength conversion element and the side surface of the substrate, and the bottom surface of the reflective side cladding being on the top surface of the insulating side cladding. The thermal conductivity of the reflective side coating is greater than that of the insulating side coating.

2. The light-emitting device according to claim 1, wherein, The reflective cladding is arranged to guide heat away from the wavelength conversion element.

3. The light-emitting device according to claim 1, wherein, The reflective coating has a thermal conductivity of at least 200 W / mK.

4. The light-emitting device according to claim 1, wherein: The insulating side cladding layer includes a first dielectric material, which includes at least one of TiO2 or a white solder mask. The reflective side coating comprises an adhesive material filled with metal powder.

5. The light-emitting device according to claim 1, wherein: The wavelength conversion element is wider than the substrate, such that a portion of the surface of the wavelength conversion element protrudes from the substrate, and The reflective side coating is thermally coupled to the side of the wavelength conversion element and the portion of the wavelength conversion element that protrudes from the surface of the substrate.

6. The light-emitting device according to claim 1, wherein, The insulating side cladding is arranged to insulate the semiconductor structure from the reflective side cladding.

7. The light-emitting device according to claim 1, wherein, The reflective coating comprises silver.

8. A light-emitting device, comprising: A light-emitting diode (LED) die includes a substrate and semiconductor structures and wavelength conversion elements located on opposite sides of the substrate, each having a top surface, a bottom surface, and a side surface; An insulating side cladding layer surrounds the sides of the semiconductor structure of the LED die and includes a first adhesive material filled with reflective particles; and A reflective side coating includes a top surface, a bottom surface, and a side surface. The side surface of the reflective side coating surrounds and contacts the substrate of the LED die and the side surface of the wavelength conversion element. The bottom surface of the reflective side coating is on the top surface of the insulating side coating. The reflective side coating includes a second adhesive material filled with metal powder. The reflective side coating is thermally coupled to the wavelength conversion element. The thermal conductivity of the reflective side coating is greater than that of the insulating side coating.

9. The light-emitting device according to claim 8, wherein, The reflective side coating comprises a silver material, an adhesive, and at least one additive, the additive being arranged to promote adhesion between the wavelength conversion element and the reflective side coating.

10. The light-emitting device according to claim 8, wherein, The insulating side cladding is arranged to substantially cover one or more sides of the semiconductor structure, and the reflective side cladding is arranged to substantially cover one or more sides of the wavelength conversion element.

11. The light-emitting device according to claim 8, wherein, The insulating side cladding is arranged to insulate the semiconductor structure from the reflective side cladding.

12. The light-emitting device according to claim 8, wherein, The reflective cladding is arranged to surround the wavelength conversion element and substantially cover one or more sides of the wavelength conversion element.

13. The light-emitting device according to claim 8, wherein, The reflective cladding is arranged to guide heat away from the wavelength conversion element.

14. The light-emitting device according to claim 8, wherein, The reflective coating comprises silver.

15. A method for manufacturing a light-emitting device, comprising: A light-emitting diode (LED) die is placed on a support, the LED die comprising: Semiconductor structure; and Wavelength conversion element formed on the semiconductor structure; An insulating side coating is formed around the semiconductor structure; and A reflective side cladding is formed around the wavelength conversion element and stacked on the insulating side cladding, the reflective side cladding having a first surface above the second surface of the insulating side cladding. The thermal conductivity of the reflective side coating is greater than that of the insulating side coating.

16. The method according to claim 15, wherein, Forming the insulating side coating includes: The first template is placed on the LED chip, and the first template forms a groove around the LED chip; Applying insulating materials to the trenches; and Remove the first template to allow insulating material to diffuse to one or more sides of the semiconductor structure.

17. The method according to claim 16, wherein, The trench is deeper than the height of the semiconductor structure, and the insulating material is applied in sufficient quantity to substantially cover one or more sides of the semiconductor structure when the first template is removed.

18. The method according to claim 15, wherein, Forming the reflective side coating includes: The second template is placed on the LED chip, and the second template forms a groove around the LED chip; Applying reflective materials to the trenches; and The second template is removed to allow the reflective material to diffuse to one or more sides of the wavelength conversion element.

19. The method according to claim 18, wherein, The reflective material is applied in sufficient quantity to substantially cover one or more sides of the wavelength conversion element when the second template is removed, without spilling onto the surface of the wavelength conversion element.

20. The method of claim 15, wherein the reflective side coating has a thermal conductivity of at least 200 W / mK and comprises silver.

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