TW201924094A - Light emitting device package - Google Patents

Abstract

A light emitting element and a method for forming the light emitting element are disclosed herein. The light emitting element may include a substrate, a reflective layer formed on the substrate, a coating layer formed on the reflective layer, and a sidewall disposed on the substrate. The sidewall can be configured to form a reflective cup. A light emitting diode (LED) wafer can be placed in the reflection cup. An opening may be formed in the coating layer to expose a portion of the reflective layer. A line can connect the LED chip to the substrate through the portion of the reflective layer exposed through the opening in the coating layer.

Description

Light emitting element package

The present invention relates generally to a light emitting element, and more particularly to a light emitting element package.

In various applications, light emitting diodes ("LEDs") are often used as light sources. The main functional part of an LED can be a semiconductor wafer, which includes two injection layers of opposite conductivity types (p-type and n-type), and a light-emitting layer for radiation recombination, in which carrier injection occurs. Semiconductor wafers are usually placed in a package that provides electrical connection between the LED chip and the outside world in addition to preventing vibration and mechanical shock.

LED packaging can also play an important role in light collection. Specifically, the LED package may include a reflective layer formed under the packaged LED chip. The reflective layer can reflect light in one direction to improve luminous efficiency. However, due to exposure to moisture and corrosive small molecular materials, the reflective layer is often susceptible to corrosion. When the reflective layer in an LED package is corroded, the light output efficiency of the LED package can be significantly reduced, and the color of the light generated by the LED package can be changed.

Therefore, there is a need for a novel LED package design that protects the reflective layer from corrosion due to exposure to moisture and / or other corrosive materials.

According to one aspect of the present invention, a light emitting element may include: a substrate; a reflective layer formed on the substrate; a coating layer formed on the reflective layer; and a side wall disposed on the substrate on. The side wall can be configured to form a reflector cup. A light emitting diode (LED) wafer can be placed in the reflection cup. An opening may be formed in the coating layer to expose a portion of the reflective layer. A line can connect the LED chip to the substrate through the portion of the reflective layer exposed through the opening in the coating layer.

According to another aspect of the present invention, a light emitting element may include: a substrate; a reflective layer formed on the substrate; a light emitting diode (LED) wafer coupled to the substrate via an adhesive layer; and A side wall is disposed on the substrate. The side wall can surround the LED chip to form a reflective cup. A coating layer may be formed on the reflective layer. The coating layer may be formed of an inorganic polymer and configured to form a seal around the adhesive layer.

According to another aspect of the present invention, a method for manufacturing a light emitting element may include: molding an electrically insulating compound onto a first lead frame and a second lead frame to form a substrate and a reflective cup. The first lead frame and the second lead frame may each include a respective top surface of a reflective layer plated with a reflective material to form a reflective layer of the substrate. A light emitting diode (LED) wafer can be mounted in the reflection cup using an adhesive layer deposited on the reflection layer. A coating layer may be formed on the reflective layer. The coating layer may be an inorganic material and configured to form a seal around the adhesion layer. An opening may be formed in the coating layer to expose a portion of the reflective layer. A line can connect the LED chip to the substrate through the portion of the reflective layer exposed through the opening in the coating layer.

This application claims the rights of US Patent Application No. 15 / 788,347, filed on October 19, 2017, and European Application No. 18153901.6, filed on January 29, 2018, the contents of which are hereby incorporated by reference Incorporated herein.

According to aspects of the present invention, a solid state light emitting package (hereinafter referred to as "LED package") including a reflective layer and a coating layer is disclosed. A coating layer is formed on the reflective layer to protect it from corrosion. The coating layer may be formed of an inorganic material. The use of an inorganic material for the coating layer can be advantageous because, compared to organic materials, inorganic materials are less prone to yellowing and less susceptible to other types of damage caused by exposure to light.

According to an aspect of the present invention, the LED package may include a light emitting diode (LED) chip surrounding to define a side wall of a reflective cup. The sidewall may be formed above the reflective layer and intersect the reflective layer. The contact point between the sidewall and the reflective layer can be called an "interface". The interface between the sidewall and the reflective layer may be permeable to some extent and / or other small molecule corrosive materials. In this regard, the coating layer may be configured to seal the interface and thus prevent moisture and / or other corrosive materials from passing through the interface into the reflective cup.

According to an aspect of the present invention, the LED chip may be bonded to the bottom of the reflective cup using an adhesive. The coating layer can at least partially cover the sidewall of the LED chip, thereby sealing off the adhesive from the rest of the reflector cup. Therefore, the coating layer can isolate the adhesive from the moisture and / or other corrosive materials present in the reflective cup, thereby reducing the possibility of wafer attachment failure.

Examples of different LED implementations will now be described more fully below with reference to the accompanying drawings. These examples are not mutually exclusive, and features found in one example can 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 accompanying drawings are provided for illustrative purposes only, and they are not intended to limit the invention in any way. Similar component symbols throughout the text refer to similar components.

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

It will be understood that when a component (such as a layer, region or substrate) is referred to as being "on another component" or "extending to another component", it may be directly on the other component or directly extend to the other component. Intermediate components may also be present on the component. In contrast, when a component is referred to as being "directly on" or "directly extending onto" another component, there are no intervening components. It will also be understood that when a component is referred to as being "connected" or "coupled" to another component, it can be directly connected or coupled to the other component, or intervening components may be present. In contrast, when a component is referred to as being "directly connected" or "directly coupled" to another component, there are no intervening components present. It will be understood that in addition to any orientation depicted in the figures, these terms are intended to cover different orientations of the components.

Relative terms such as "below" or "above" or "above" or "below" or "horizontal" or "vertical" may be used herein to describe one component, layer or region and another component as shown in the figure , Layer, or zone relationship. It will be understood that in addition to the orientation depicted in the figures, these terms are also intended to cover different orientations of the elements.

FIG. 1A is a schematic perspective view of an LED package 100 according to an aspect of the present invention. FIG. 1B is a schematic cross-sectional view of the LED package 100 taken along the axis A-A. FIG. 1C is a top view of an LED package 100 according to an aspect of the present invention. The encapsulation compound 160 described further below is omitted from FIGS. 1A and 1C to reveal the components below it.

As shown, the LED package 100 includes a substrate 110 on which a reflective layer 120 is formed. The reflective layer 120 is at least partially covered by a coating layer 170. A sidewall 130 is formed above the reflective layer to define a reflective cup 140. An LED chip 150 is disposed inside the reflection cup 140. The ohmic contacts (not shown) of the LED chip 150 are electrically coupled to the leads 154 and 156, respectively. After the LED wafer 150 is placed in the reflection cup 140, the reflection cup 140 is filled with an encapsulation compound 160.

The substrate 110 may be formed of many different materials, including electrically insulating materials and / or conductive materials. For example, the substrate 110 may include a ceramic (such as alumina, aluminum nitride, silicon carbide) or a polymeric material (such as polyimide, polyester, etc.). Additionally or alternatively, the substrate may include at least one lead frame. Additionally or alternatively, the substrate 110 may include a plurality of lead frames coupled to a non-conductive polymer material. The leads 154 and 156 may be provided on the bottom of the substrate 110 or another suitable location (such as the side of the substrate 110). The leads 154 and 156 may be electrically coupled to an ohmic contact (not shown) of the LED chip 150, thus providing an interface for connecting the LED chip 150 to various types of electronic circuits.

The reflective layer 120 is formed above the substrate 110 to reflect the light emitted by the LED chip 150 in an upward direction to improve the light emitting efficiency of the LED package 100. In this example, the reflective layer 120 is formed of silver (Ag). However, alternative embodiments where the reflective layer comprises another highly reflective material are possible. Additionally or alternatively, the reflective layer 120 may include a combination of materials. For example, the reflective layer 120 may include a highly reflective material and another material having a high refractive index. Therefore, in addition to improving the light emitting efficiency of the LED package 100, the reflective layer 120 can also be used to further shape the optical characteristics of the light emitted from the LED package 100.

In this example, the reflection cup 140 is shaped as a frustum of a cone. However, alternative embodiments in which the reflection cup 140 has a different shape (eg, a cylindrical shape, a cubic shape, etc.) are possible. In this regard, the invention is not limited to any particular shape and / or physical size of the reflector cup. Although the side wall 130 is higher than the LED chip 150 in this example, in some embodiments, the side wall 130 of the reflector cup 140 may be shorter than the LED chip 150 so that the light emitting surface of the LED chip is positioned above the top of the side wall 130. Although in this example, the sidewall 130 completely surrounds the LED wafer 150, alternative implementations in which the sidewall 130 only partially surrounds the LED wafer 150 or does not completely surround the LED wafer 150 are feasible. Therefore, as used throughout the present invention, the term "reflective cup" may refer to any functional area of the LED package 100 mounted on the LED chip 150.

In some embodiments, the sidewall may be formed of a metal material and bonded to the substrate 110 by a solder or an epoxy bonding agent. Additionally or alternatively, in some embodiments, the sidewall 130 may be formed of a resin, such as an epoxy resin or a thermoplastic resin. Additionally or alternatively, in some embodiments, the sidewall 130 may be integral with the substrate 110. Additionally or alternatively, in some embodiments, the sidewall 130 may be etched onto the substrate 110. Additionally or alternatively, in some embodiments, the sidewall 130 may be molded onto the substrate 110.

The LED chip 150 is disposed at the center of the reflection cup 140 to obtain uniform light distribution characteristics. The LED chip 150 may be any suitable type of semiconductor light emitting element. The LED chip 150 may be provided with contacts (for example, an anode contact and a cathode contact), which are electrically connected to the leads 154 and 156, respectively. Electrical connections can be made by using bonding wires, attachment pads, and / or any suitable type of conductor. Although in this example, only one LED wafer 150 is placed in the reflection cup 140, an alternative implementation in which multiple LED wafers are placed in the reflection cup 140 is feasible. For example, different color LEDs can be placed in the reflection cup 140 to achieve a light output of one of the changed colors. Each LED chip placed in the reflection cup 140 can be connected to a different set of leads.

As shown, the encapsulation compound 160 may be injected into the reflective cup 140 to protect the LED wafer 150 from damage. The encapsulation compound may include silicone, epoxy, and / or any other suitable type of material. In some embodiments, a desired emission color can be obtained by mixing phosphorus into an encapsulation compound.

The coating layer 170 is formed over the reflective layer 120 to protect it from corrosion. In some embodiments, the coating layer may be transparent or reflective in the visible range (360 nm to 850 nm), and it may have a refractive index in the range of 1.40 to 1.80. Additionally or alternatively, in some embodiments, the coating layer 170 may have a thickness in a range of 40 nm to 20 μm.

The coating layer may be formed of any suitable type of inorganic material. For example, and without limitation, the coating layer may be formed of an inorganic material selected from one of the group consisting of: Si-O material, Si-ON material, Al-O material, Al-N material, Si-N Materials and Ti-O materials. Additionally or alternatively, the coating layer may be formed from any suitable type of organic material. For example, the coating layer may be formed of an organic material selected from the group consisting of a Si-C material and a Si-C-N material. It may be advantageous to use an inorganic material to form the coating layer 170 because the organic material may release a gas that damages the reflective layer 120 when exposed to light. This is particularly true when the reflective layer 120 includes silver and / or a silver-based material. Additionally or alternatively, in some embodiments, the coating layer may include a stack including Si-O material, Si-ON material, Al-O material, Al-N material, Si-N material, and Ti- One or more of the O materials. Additionally or alternatively, in some embodiments, the coating layer may include an alternating stack including Si-O material, Si-ON material, Al-O material, Al-N material, Si-N material, and At least two of Ti-O materials. Additionally or alternatively, in some embodiments, the coating layer may be a stack including only one of the inorganic materials (eg, an alternate stack). Additionally or alternatively, in some embodiments, the coating layer may include a stack including one of organic materials such as Si-C materials and Si-C-N materials.

In this example, the reflective layer 120 is introduced before the sidewall 130 is formed. Therefore, the reflective layer 120 extends below the sidewall 130 and intersects the sidewall 130 at an interface 132, which is the contact point between the reflective layer 120 (or the substrate 110) and the sidewall 130. Contact can be direct or indirect. That is, other layers / components (such as adhesives, additional layers, etc.) may or may not be present at the interface 132. In the figure, the relative size of the interface 132 is extremely enlarged to achieve a clearer drawing.

The interface 132 can be permeable to moisture and other small molecular materials. Such materials can damage the reflective layer 120 and cause the LED package 100 to fail. To address this vulnerability, the coating layer 170 may be configured to seal the interface 132. For example, the coating layer 170 may be configured to have a thickness greater than a thickness of the interface 132. As another example, the coating layer 170 may be configured to extend upwardly along the sidewall 130 as shown, and seal the interface 132 in this manner. Therefore, in some aspects, it may be advantageous to form the coating layer 170 above the reflective layer 120 because the coating layer 170 can prevent (or reduce) moisture and other small molecular materials from passing through the sidewall 130 and the components below Interface.

In this example, the LED chip 150 may be bonded to the bottom of the reflection cup 140 using an adhesive 152. The adhesive 152 may include a solder adhesive, a non-conductive epoxy adhesive, and / or any other suitable type of adhesive material. In some embodiments, the adhesive 152 may include a non-conductive adhesive for bonding the LED wafer 150 to the substrate 110. Additionally or alternatively, in some embodiments, the adhesive 152 may include a solder adhesive used to bond the contacts of the LED chip 150 to the underlying attachment pads to connect the leads 154 and 156 to The contacts of the LED chip 150. Additionally or alternatively, in some examples, the adhesive 152 may include a solder adhesive for bonding the ohmic contacts of the LED chip 150 to the underlying attachment pad (eg, see FIG. 5) and for further strengthening One of the joints between the LED chip 150 and the substrate 110 is a non-conductive underfill member.

In some aspects, the adhesive 152 may be susceptible to damage from moisture and / or other materials applied in the reflector cup 140. To address this vulnerability, the coating layer 170 may be configured to seal the adhesive 152 from the rest of the reflective cup 140 (completely or partially). For example, the coating layer 170 may be configured to have a thickness greater than the thickness of the layer formed by the adhesive 152. As another example, the coating layer 170 may be configured to extend upwardly along the sidewall (s) of the LED wafer 150 as shown. Accordingly, the coating layer 170 may partially or substantially cover one or more sidewalls of the LED wafer 150 and seal the adhesive 152 in this manner. It may be advantageous to form a coating layer 170 over the reflective layer 120 because the coating layer 170 may reduce the likelihood of wafer attachment failure due to damage to the adhesive 152.

The portion of the coating layer 170 covering the sidewall 130 may have a tapered cross section as shown and / or any other suitable shape. In some implementations, the coating layer 170 may cover the entire surface of the side wall 130 facing the LED wafer 150. Alternatively, in some embodiments, the coating layer 170 may cover only a part of the entire surface facing the side wall 130 of the LED wafer 150. Therefore, the present invention is not limited to any specific degree of coverage of the sidewall 130 by the coating layer 170.

In some implementations, the coating layer 170 may cover all (four) sides of the LED wafer 150 as shown. The portion of the coating layer 170 covering any particular side of the LED wafer 150 may have a tapered cross section and / or any other suitable shape. In the present example, the LED wafer has a bottom surface coupled to one of the substrates 110, substantially parallel to the bottom surface and facing one of the top surfaces (eg, a light emitting surface). Therefore, the side of the LED chip 150 is a surface extending between the top surface and the bottom surface. In this example, the sides of the LED chip 150 are connected to the top surface and the bottom surface at a right angle, however, an alternative embodiment in which the LED chip 150 has a tapered side is feasible.

Although in this example, each of the four sides of the LED wafer is only partially covered by the LED wafer 150, alternative implementations in which one or more sides of the LED wafer 150 are substantially covered by the coating layer 170 are feasible. In this regard, if the coating layer 170 is deposited over 80% of the surface on one side of the LED wafer 150 (for example, deposited over 98% or more, deposited over 95% or more, deposited Over 90% or more, deposited over 85% or more, etc.), the side may be substantially covered by the coating layer 170. In short, the invention is not limited to any specific degree of coverage of the side of the LED wafer 150 by the coating layer 170.

As described above, in the present example, the reflective layer 120 is introduced before the sidewall 130 is formed. However, alternative embodiments in which the reflective layer 120 is formed after the sidewall 130 is provided are feasible. In these examples, the reflective layer 120 will not extend below the sidewall 130, but the coating layer 170 may still be configured to seal any gaps that may exist between the sidewall 130 and the substrate 110 (or formed on the substrate 110) Another layer / component to the side wall 130).

Further, in this example, the reflective layer 120 is formed before the LED wafer 150 is mounted in the reflective cup 140. However, an alternative embodiment in which the reflective layer 120 is formed after the LED wafer 150 is installed in the reflective cup 140 is feasible. In these examples, the reflective layer 120 may surround the LED chip 150 without extending below it.

FIG. 1D is a schematic cross-sectional view of an LED package 100d, which includes a coating layer 170d. The coating layer 170d may have the same composition, refractive index, and / or thickness as the coating layer 170. However, unlike the coating layer 170, the coating layer 170d does not cover the side of the LED wafer 150 because any contact between the coating layer 170d and the side of the LED wafer is accompanied by the coating layer 170d, which is adjacent to the LED wafer The coating layer 170d is deposited to form a substantially flat shape. Similarly, in the example of FIG. 1D, the coating layer 170 d does not cover the side facing the side wall 130 of the LED wafer 150, because any contact between the coating layer 170 d and the side wall 130 is accompanied by the coating layer 170 d, which is adjacent to A coating layer 170d is deposited near the LED wafer to form a substantially flat shape.

This is in contrast to the coating layer 170, which at least partially covers the sidewall 130 and the wall of the LED chip 150. To achieve this effect, the coating layer 170 is formed in a concave shape, which is open in the middle where the LED chip 150 is positioned, and its respective edges at least partially conform to the geometry of the sidewall 130 and / or the geometry of the (several) sides of the LED chip 150 shape. As shown, each of the respective edges of the concave shape may have a tapered cross-section, and as shown, it may extend above the side wall 130 or the wall of the LED chip 150. Additionally or alternatively, each of the respective edges may be angled relative to the substrate 110. In some aspects, the depth of the concave shape may be greater than the thickness of the coating layer 170 (eg, the size is at least 2 times, at least 5 times, at least 10 times, at least 100 times, etc.). The depth of the concave shape may be the distance between the end of one of the edges and the base 110. The thickness of the coating layer 170 may be a thickness conventionally referred to as the thickness of one layer. For example, the thickness of the coating layer 170 may be a distance between a first surface and a second surface of the coating layer, wherein the two surfaces are substantially parallel to each other and parallel to a plane of the substrate 110.

In some aspects, the process for forming the coating layer may determine whether it covers the side (s) of the side wall 130 and / or the LED wafer 150. For example, when forming a coating layer using vapor deposition, the side of the LED wafer 150 may remain uncovered. In contrast, when forming a coating layer using liquid deposition, one or more sides of the LED wafer 150 may be at least partially covered by the coating layer. In the example of FIGS. 1A to 1D, the coating layer 170 is formed using liquid deposition, and the coating layer 170 d is formed using vapor deposition.

FIG. 2A is a schematic cross-sectional view of an LED package 200 according to an aspect of the present invention. FIG. 2B is a schematic top view of the LED package 200 according to an aspect of the present invention. The encapsulation compound 160 is omitted from FIG. 2B to reveal the components below it.

In the example of FIGS. 2A to 2B, a substrate 210 includes a first conductive lead frame 212, and the first conductive lead frame 212 is coupled to a second conductive lead frame 214 through a non-conductive member 216. The leads 254 and 256 may be integrally formed on the first lead frame 212 and the second lead frame 214, respectively, to provide an interface between the LED chip 250 and the outside. A reflective layer 220 is formed over the substrate 210 from silver and / or other conductive materials. The reflective layer includes a first portion 222 and a second portion 224. The first portion 222 and the second portion 224 are electrically insulated from each other by a non-conductive member 216. The non-conductive member 216 may be formed by molding a reflective polymer material onto the first lead frame 212 and the second lead frame 214. The first portion 222 and the second portion 224 of the reflective layer 220 may be formed by plating the lead frames 212 and 214 with silver before molding the reflective polymer material into the lead frames 212 and 214.

A coating layer 270 is formed on the reflective layer 220. The coating layer 270 may have the same thickness, refractive index, and / or composition as any of the coating layers 170 and 170d. However, unlike these coating layers, the coating layer 270 may be patterned to include openings 272 and 274 that expose the surface of the reflective layer 220 to allow bonding wires 280 and 290 to be connected to the lead frame 212 and 214 (or reflective layer portions 222 and 224). The openings 272 and 274 may be formed using any suitable type of masking and / or photolithography techniques.

In the example of FIGS. 2A to 2B, the coating layer 270 substantially covers at least one (and / or all) sides of the LED wafer 250. As described above, if the coating layer 270 is deposited over 80% of the surface on one side (for example, over 98% or more, over 95% or more, over 90% or more , Deposited on top of 85% or more, etc.), this side may be substantially covered by the coating layer 270. In addition, according to an aspect of the present invention, the coating layer 270 may cover a side of the non-conductive member 216 that is flush with the top surface of the reflective layer 220. In this regard, the coating layer 270 may form a barrier between the non-conductive component 216 and the packaging component positioned in the reflective cup 140.

The LED chip 250 may be the same as or similar to the LED chip 150 discussed with respect to FIGS. 1A to 1D. The LED chip 250 may be mounted on the lead frame 212 using an adhesive 252, as shown. To facilitate the safe installation of the LED chip 250, the size of the lead frame 212 may be larger than the lead frame 214, as shown.

A cathode contact (not shown) of the LED chip 250 is coupled to a portion of the first lead frame 212 exposed through the opening 272 via a bonding wire 280. An anode contact (not shown) of the LED wafer 250 is coupled to a portion of the second lead frame 214 exposed through the opening 274 via a bonding wire 290. In some implementations, the bonding wires 280 and 290 can be soldered directly to the reflective layer portions 222 and 224. Additionally or alternatively, in some implementations, the bonding wires may be attached to the lead frames 212 and 214 via conductive traces provided on the reflective layer portions 222 and 224, respectively. In short, the present invention is not limited to any particular technique for connecting the bonding wires 280 and 290 to the substrate 210. In some aspects, the availability of the openings 272 and 274 allows bonding wires 280 and 290 to be installed after the coating layer 270 is formed.

FIG. 3 is a cross-sectional view of an LED package 300 according to one aspect of the present invention. The LED package 300 has a structure that is almost the same as the structure of the LED package 200. However, unlike the LED package 200, the LED package 300 includes a coating layer 370 formed after connecting the bonding wires 280 and 290 to the first lead frame 212 and the second lead frame 214, respectively. Therefore, the coating layer 370 covers the contact point 382 between the bonding wire 280 and the first lead frame 212 (or the reflective layer portion 222). Similarly, the coating layer 370 covers the contact point 392 between the bonding wire 290 and the second lead frame 214 (or the reflective layer portion 224). Any of the contact points 382 and 392 may include the ends of one of the bonding wires 280 and 290, a conductive adhesive, a solder bump, a conductive trace, and / or one of any other suitable types of connection components Or more. Covering the contact points 382 and 392 with the coating layer 370 can further improve the reliability of the electrical connection between the LED chip 250 and the substrate 210.

FIG. 4 is a cross-sectional view of an example of a flip-chip LED package 400 according to an aspect of the present invention. The LED package 400 includes a substrate 410 including a first conductive lead frame 412 coupled to a second conductive lead frame 414 through a non-conductive component 416. A reflective layer 420 is formed on the substrate 410 from silver and / or other conductive materials. The reflective layer includes a first portion 422 and a second portion 424. The first portion 422 and the second portion 424 are electrically insulated from each other by a non-conductive member 416. The leads 454 and 456 may be integrally formed on the bottom surfaces of the lead frames 412 and 414 to provide a member for connecting the LED package 400 to various types of electronic circuits.

The LED chip 450 may be any suitable type of semiconductor light emitting element characterized by a flip-chip configuration. A first portion 422 of the reflective layer 420 is coupled to an attachment pad 480 of an LED chip 450, and a second portion 424 of the reflective layer 420 is coupled to an attachment pad 490 of the LED chip 450. A wafer underfill member 452 may be injected and molded between the attachment pads 480 and 490 to strengthen the bonding between the LED chip 450 and the substrate 410, and to electrically isolate the attachment pads 480 and 490 from each other.

A coating layer 470 is formed over the reflective layer 420, as shown. In some implementations, the coating layer 470 may at least partially cover a wall of the LED wafer 450. In some embodiments, the coating layer can form a seal around the attachment pads 480 and 490, as shown. Accordingly, the coating layer 470 may isolate the attachment pads 480 and 490 and the underfill member 452 from the rest of the reflection cup 140. According to aspects of the present invention, the coating layer 470 may have the same composition, thickness, and / or refractive index as the coating layer 170. It may be advantageous to form a coating layer 470 over the reflective layer 420 because the coating layer 470 may reduce the possibility of wafer attachment failure.

FIG. 5 is a flowchart of an example of a process 500 for manufacturing an LED package according to aspects of the present invention. According to the program, in step 510, a first lead frame and a second lead frame are provided. Both lead frames can be plated with silver or another reflective material. In addition, the two boxes can be joined together by a molding compound to produce the assembly 600a shown in FIG. 6A.

In step 520, a reflective polymer material is molded over the lead frame to form a substrate and a reflective cup. As a result, the assembly 600b shown in FIG. 6B is produced. According to aspects of the invention, the reflector can be formed by using any suitable type of procedure. For example, in some embodiments, the reflective cup may be formed by injection molding or another similar procedure. In addition, in some embodiments, trimming can be performed after molding the reflective cup to achieve a desired shape of one of the reflective cups.

In step 530, an LED chip is placed in a reflective cup and attached to one of the lead frames forming a substrate. As a result of performing step 530, the assembly 600c shown in FIG. 6C is generated.

At step 540, wire bonds are attached to the contacts of the LED wafer and lead frames designated for the anode and cathode, respectively. As a result of performing step 540, the assembly 600d shown in FIG. 6D is generated.

In step 550, a liquid solution material containing a precursor is applied to the reflective cup formed in step 520. The liquid solution material may be applied by dispensing, spraying, spin coating, and / or any other suitable technique. The liquid solution material can be dispensed in a sufficient amount to form a final coating layer over the silver plating layer of the lead frame and partially (or substantially) on the sidewall of the reflection cup and above the LED chip. As a result of performing step 550, the assembly 600e shown in FIG. 6E is generated.

At step 560, the entire package (e.g., assembly 600e) produced so far is heated to a first temperature with the attached LED chip, bonding wires, and the dispensed liquid solution to drive off as a liquid solution The solvent in the part of the material allows the cross-linking chemical reaction to begin. The package can be continuously heated at the first temperature until ninety percent (90%) or more of the solvent in the solution is expelled. Then, the entire package is brought to a higher temperature so that the precursor material is completely converted into the final layer, which has high density and low permeability to water vapor and many other small molecule gaseous materials. After the final conversion of the precursor material, a thin, transparent, and highly durable coating is formed on the reflective coating, and partly formed on the sidewall of the reflective cup and above the LED chip. In some aspects, the layers may be similar to one or more of the coating layers discussed with respect to FIGS. 1A-4 (eg, layers 170, 170d, 270, 370, and 470). As a result of performing step 560, the assembly 600f shown in FIG. 6F is generated.

At step 570, an encapsulating material with or without a wavelength conversion component is applied to the reflective cup, and then one of the encapsulating materials is subsequently cured. As a result of performing step 570, one final LED package 600g shown in FIG. 6G is generated.

1A to 6G are provided as examples only. At least some of the components discussed with respect to these figures may be configured, combined, and / or omitted entirely in a different order. It will be understood that the provision of examples described herein and clauses expressed as "such as", "for example", "including", "in some aspects", "in some embodiments", etc. should not be interpreted as The disclosed subject matter is limited to specific examples.

Although the present invention has been described in detail, those skilled in the art will appreciate that, for the purposes of the present invention, the present invention can be modified 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 shown and described.

100‧‧‧Light Emitting Diode (LED) Package

100d‧‧‧Light Emitting Diode (LED) Package

110‧‧‧ substrate

120‧‧‧Reflective layer

130‧‧‧ sidewall

132‧‧‧ interface

140‧‧‧Reflection Cup

150‧‧‧light emitting diode (LED) chip

152‧‧‧Adhesive

154‧‧‧Leader

156‧‧‧Leader

160‧‧‧ Encapsulation compound

170‧‧‧ Coating

170d‧‧‧coating

200‧‧‧Light Emitting Diode (LED) Package

210‧‧‧ substrate

212‧‧‧First conductive lead frame / first lead frame

214‧‧‧Second conductive lead frame / second lead frame

216‧‧‧ Non-conductive parts

220‧‧‧Reflective layer

222‧‧‧The first part of the reflective layer / the part of the reflective layer

224‧‧‧The second part of the reflective layer / the part of the reflective layer

250‧‧‧Light Emitting Diode (LED) Chip

252‧‧‧Adhesive

254‧‧‧Leader

256‧‧‧Leader

270‧‧‧ Coating

272‧‧‧ opening

274‧‧‧ opening

280‧‧‧ bonding wire

290‧‧‧ bonding wire

300‧‧‧Light Emitting Diode (LED) Package

370‧‧‧ Coating

382‧‧‧contact point

392‧‧‧contact point

400‧‧‧Light Emitting Diode (LED) Package

410‧‧‧ substrate

412‧‧‧the first conductive lead frame

414‧‧‧Second conductive frame / lead frame

416‧‧‧non-conductive parts

420‧‧‧Reflective layer

422‧‧‧The first part of the reflective layer

424‧‧‧The second part of the reflective layer

450‧‧‧Light Emitting Diode (LED) Chip

452‧‧‧ Wafer Underfill Parts

454‧‧‧Leader

456‧‧‧Leader

470‧‧‧ Coating

480‧‧‧ Attachment Pad

490‧‧‧ Attachment pad

500‧‧‧ procedure

510‧‧‧step

520‧‧‧step

530‧‧‧step

540‧‧‧step

550‧‧‧step

560‧‧‧step

570‧‧‧step

600a‧‧‧Assembly

600b‧‧‧Assembly

600c‧‧‧Assembly

600d‧‧‧Assembly

600e‧‧‧Assembly

600f‧‧‧ Assembly

600g‧‧‧final light emitting diode (LED) package

The drawings described below are for illustration purposes only. The drawings are not intended to limit the scope of the invention. Similar element symbols shown in the figures designate the same parts in various embodiments.

1A is a schematic perspective view of an example of an LED package according to an aspect of the present invention;

FIG. 1B is a schematic cross-sectional view of the LED package of FIG. 1A according to an aspect of the present invention; FIG.

FIG. 1C is a top view of the LED package of FIG. 1A according to aspects of the present invention; FIG.

1D is a schematic cross-sectional view of another example of an LED package according to an aspect of the present invention;

2A is a schematic cross-sectional view of another example of an LED package according to an aspect of the present invention;

2B is a schematic top view of the LED package of FIG. 2A according to aspects of the present invention;

3 is a schematic cross-sectional view of another example of an LED package according to an aspect of the present invention;

4 is a schematic cross-sectional view of another example of an LED package according to an aspect of the present invention;

5 is a flowchart of an example of a procedure for manufacturing an LED package according to aspects of the present invention;

FIG. 6A is a schematic cross-sectional view of an example of an LED package assembly produced at a first stage of a process of FIG. 5 according to aspects of the present invention; FIG.

FIG. 6B is a schematic cross-sectional view of an example of an LED package assembly produced at a second stage of a procedure of FIG. 5 according to aspects of the present invention; FIG.

FIG. 6C is a schematic cross-sectional view of an example of an LED package assembly produced at a third stage of a process of FIG. 5 according to aspects of the present invention; FIG.

6D is a schematic cross-sectional view of an example of an LED package assembly produced at a fourth stage of one of the procedures of FIG. 5 according to aspects of the present invention;

6E is a schematic cross-sectional view of an example of an LED package assembly produced at a fifth stage of one of the procedures of FIG. 5 according to aspects of the present invention;

6F is a schematic cross-sectional view of an example of an LED package assembly produced at a sixth stage of one of the procedures of FIG. 5 according to aspects of the present invention; and

6G is a schematic cross-sectional view of one of the final LED packages produced at the final stage of the process of FIG. 5 according to aspects of the present invention.

Claims (17)

A light emitting element includes: A base A reflective layer formed on the substrate; A coating layer formed on the reflective layer; An opening in the coating layer, the opening exposing a part of the reflective layer; A side wall disposed on the base, the side wall configured to form a reflection cup; A light emitting diode (LED) wafer, which is placed in the reflector; and A line that connects the LED chip to the substrate through the portion of the reflective layer exposed through the opening in the coating layer. The light-emitting element according to claim 1, wherein the LED chip is coupled to the substrate via an adhesive layer, and the coating layer is configured to form a seal around the adhesive layer. Such as the light-emitting element of claim 1, wherein: The sidewall is formed on the reflective layer. The sidewall meets the reflective layer at an interface, the interface being a contact point between the sidewall and the reflective layer, and The coating is configured to seal the interface to prevent moisture from entering the reflective cup. The light-emitting element according to claim 1, further comprising extending from the LED wafer to the substrate to form a wire bonded to one of the substrates, wherein the bonding is covered by the coating layer. The light-emitting element according to claim 1, wherein the coating layer is formed of an inorganic material selected from the group consisting of Si-O material, Si-ON material, Al-O material, Al-N material, Si-N materials, and Ti-O materials. The light-emitting element according to claim 1, wherein the coating layer has a refractive index in a range of 1.40 to 1.80. The light-emitting element according to claim 1, wherein the coating layer has a thickness in a range of 40 nm to 20 µm. A light emitting element includes: A base A reflective layer formed on the substrate; A light emitting diode (LED) chip, which is coupled to the substrate via an adhesive layer; A side wall disposed on the substrate, the side wall surrounding the LED chip to form a reflection cup; A coating layer formed on the reflective layer, wherein the coating layer is formed of an inorganic polymer and configured to form a seal around the adhesive layer; An opening in the coating layer, the opening exposing a portion of the reflective layer; and A line that connects the LED chip to the substrate through the portion of the reflective layer exposed through the opening in the coating layer. Such as the light-emitting element of claim 8, wherein: The reflective layer is formed between the substrate and the LED chip. The coating layer is configured to cover a portion of the reflective layer that is not covered by the LED wafer, and The coating layer is further configured to cover at least a portion of a wall of the LED wafer. Such as the light-emitting element of claim 8, wherein: The sidewall is formed on the reflective layer, The sidewall meets the reflective layer at an interface, the interface being a contact point between the sidewall and the reflective layer, and The coating layer is configured to seal the interface to prevent moisture from entering the reflective cup. The light-emitting element according to claim 8, wherein the coating layer is formed of a material selected from the group consisting of: Si-O material, Si-ON material, Al-O material, Al-N material, Si -N material, and Ti-O material. The light-emitting element according to claim 8, wherein the coating layer has a refractive index in a range of 1.40 to 1.80. The light emitting element of claim 8, wherein the coating layer has a thickness in a range of 40 nm to 20 µm. A method for manufacturing a light emitting element includes: An electrically insulating compound is molded onto a first lead frame and a second lead frame to form a substrate including a reflective cup. The first lead frame and the second lead frame each include a reflective material plated. To form a respective top surface of a reflective layer of the substrate; Mounting a light emitting diode (LED) chip in the reflective cup, wherein the LED chip is mounted using an adhesive layer deposited on the reflective layer; Forming a coating layer on the reflective layer, wherein the coating layer is formed of an inorganic material and is configured to form a seal around the adhesive layer; Forming an opening in the coating layer, the opening exposing a portion of the reflective layer; and A line is formed that connects the LED chip to the substrate through the portion of the reflective layer exposed through the opening in the coating layer. The method of claim 14, wherein the coating layer is formed using a liquid deposition process. The method of claim 14, wherein the coating layer is formed of an inorganic material selected from the group consisting of: Si-O material, Si-ON material, Al-O material, Al-N material, Si -N material, and Ti-O material. The method of claim 14, wherein the coating layer has a refractive index in a range of 1.40 to 1.80 and a thickness in a range of 40 nm to 20 µm.