LED package

Abstract

According to exemplary embodiments for achieving the technical problem described above, a Light Emitting Diode (LED) package is provided. The LED package comprises: a substrate including an insulating material; upper pads disposed on an upper surface of the substrate; a side molding layer covering the upper surface of the substrate and the sides of the upper pads; an LED chip disposed on an upper surface of the substrate and configured to be electrically connected to the upper pads; a fluorescent layer disposed on the LED chip; and a reflective molding layer covering the LED chip and disposed on the substrate, comprising white silicon, wherein the reflective molding layer may expose at least a portion of the sides of the fluorescent layer.

Description

Technology Field

[0001] The technical concept of the present disclosure relates to an LED (Light Emitting Diode) package. Background Technology

[0002] LED (Light Emitting Diode) chips and LED packages containing these chips possess various advantages, such as low power consumption, high brightness, and a long lifespan, leading to an increasing range of applications as light sources. A representative example of using LED packages as a lighting source is vehicle headlights.

[0003] When using LED packages as automotive light sources, light extraction efficiency and operational reliability are critical for safety reasons. Furthermore, since automotive LED packages operate at higher outputs than standard LED packages, an efficient heat dissipation design is essential. The problem to be solved

[0004] The problem that the technical concept of the present disclosure aims to solve is to provide a Light Emitting Diode (LED) package with improved light extraction efficiency and reliability.

[0005] The problems that the technical concept of the present invention aims to solve are not limited to those mentioned above, and other unmentioned problems will be clearly understood by those skilled in the art from the description below. means of solving the problem

[0006] According to exemplary embodiments for achieving the above technical problem, a Light Emitting Diode (LED) package is provided. The LED package comprises: a substrate including an insulating material; upper pads disposed on an upper surface of the substrate; a side molding layer covering the upper surface of the substrate and the sides of the upper pads; an LED chip disposed on an upper surface of the substrate and configured to be electrically connected to the upper pads; a fluorescent layer disposed on the LED chip; and a reflective molding layer covering the LED chip and disposed on the substrate, comprising white silicon, wherein the reflective molding layer may expose at least a portion of the sides of the fluorescent layer.

[0007] According to exemplary embodiments, an LED package is provided. The LED package comprises: a substrate; lower pads disposed on the lower surface of the substrate; upper pads disposed on the upper surface of the substrate; an LED chip disposed on the upper surface of the substrate and configured to be electrically connected to the upper pads; a fluorescent layer disposed on the LED chip; a reflective molding layer covering the LED chip and disposed on the substrate and comprising white silicon; and a side molding layer covering the upper surface of the substrate, the side of the upper pads and the lower surface of the lower pads, and including a cup portion that horizontally surrounds the LED chip, the fluorescent layer and the reflective molding layer, wherein the upper surface of the cup portion is spaced further away from the substrate than the upper surface of the fluorescent layer, and the inner surface of the side molding layer facing the LED chip is obliquely inclined with respect to the upper surface of the substrate in a direction away from the LED chip.

[0008] According to exemplary embodiments, an LED package is provided. The LED package comprises: a substrate comprising aluminum oxide; upper pads disposed on the upper surface of the substrate; an LED chip disposed on the upper surface of the substrate and configured to be electrically connected to the upper pads; a fluorescent layer disposed on the LED chip and comprising PiG (Phospor in Glass); a side molding layer comprising a cup portion covering the upper surface of the substrate and the sides of the upper pads and horizontally surrounding the LED chip and the fluorescent layer; and a reflective molding layer covering the inner surface of the LED chip and the cup portion of the side molding layer and exposing at least a portion of the side of the fluorescent layer, wherein the upper surface of the reflective molding layer becomes lower as it approaches the LED chip from the side molding layer. Effects of the invention

[0009] According to exemplary embodiments, the LED package can increase the light-emitting area. Accordingly, an LED package with improved light extraction efficiency can be provided.

[0010] The effects obtainable from the exemplary embodiments of the present invention are not limited to those mentioned above, and other unmentioned effects can be clearly derived and understood by those skilled in the art to which the exemplary embodiments of the present disclosure belong from the following description. That is, unintended effects resulting from the implementation of the exemplary embodiments of the present disclosure can also be derived by those skilled in the art from the exemplary embodiments of the present disclosure. Brief explanation of the drawing

[0011] FIGS. 1a to 1c are perspective views illustrating a Light Emitting Diode (LED) package according to exemplary embodiments. FIG. 2a is a top view of an LED package according to exemplary embodiments. FIG. 2b is a side view of an LED package according to exemplary embodiments. FIG. 2c is a bottom view of an LED package according to exemplary embodiments. FIG. 2d is a cross-sectional view taken along the cutting line I-I' of FIG. 1. FIGS. 3a and FIGS. 3b are perspective views illustrating LED packages according to other exemplary embodiments. Fig. 3c is a side view of the LED package of Fig. 3a. FIG. 4a is a perspective view showing an LED package according to other exemplary embodiments. Fig. 4b is a side view of the LED package of Fig. 4a. FIG. 5a is a perspective view showing an LED package according to other exemplary embodiments. Fig. 5b is a side view of the LED package of Fig. 5a. FIG. 6a is a perspective view showing an LED package according to exemplary embodiments. FIG. 6b is a plan view of an LED package according to exemplary embodiments. FIG. 6c is a side view of an LED package according to exemplary embodiments. FIG. 6d is a cross-sectional view taken along the cutting line II-II' of FIG. 6a. FIG. 7a is a cross-sectional view illustrating an LED package according to exemplary embodiments. FIG. 7a is a cross-sectional view illustrating an LED package according to exemplary embodiments. FIG. 8 is a flowchart illustrating a method for manufacturing an LED package according to exemplary embodiments. FIGS. 9a to 9e are cross-sectional views illustrating a method for manufacturing an LED package according to exemplary embodiments. Specific details for implementing the invention

[0012] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Identical components in the drawings are denoted by the same reference numerals, and redundant descriptions thereof are omitted.

[0013] FIGS. 1a to 1c are perspective views illustrating an LED (Light Emitting Diode) package (100) according to exemplary embodiments.

[0014] More specifically, FIG. 1a illustrates an LED package (100), FIG. 1b illustrates an LED package (100) with the fluorescent layer (150) and reflective molding layer (160) omitted, and FIG. 1c illustrates a substrate (111), upper pads (112, 113), and lower pads (114, 115, 116).

[0015] FIG. 2a is a top view of an LED package (100) according to exemplary embodiments.

[0016] FIG. 2b is a side view of an LED package (100) according to exemplary embodiments.

[0017] FIG. 2c is a bottom view of an LED package (100) according to exemplary embodiments.

[0018] FIG. 2d is a cross-sectional view taken along the cutting line I-I' of FIG. 1.

[0019] Referring to FIGS. 1a through 2d, the LED package (100) can generate light based on external power. The light generated by the LED package (100) may have a wavelength in the visible light band. According to exemplary embodiments, the LED package (100) may be a light source for a lighting device.

[0020] The LED package (100) may have a roughly rectangular shape. The LED package (100) may include two faces substantially perpendicular to the X direction, two faces substantially perpendicular to the Y direction, and two faces substantially perpendicular to the Z direction.

[0021] The X direction and the Y direction are two directions substantially parallel to the upper surface (111T) of the substrate (111), and the Z direction is a direction substantially perpendicular to the upper surface (111T) of the substrate (111). The X direction, the Y direction, and the Z direction may be substantially perpendicular to each other.

[0022] The LED package (100) may include a substrate (111), upper pads (112, 113), lower pads (114, 115, 116), an LED chip (120), a Zener diode (131), wirings (135, 136), a side molding layer (140), a fluorescent layer (150), and a reflective molding layer (160).

[0023] According to exemplary embodiments, the substrate (111) may include an insulating material. According to exemplary embodiments, the substrate (111) may include aluminum oxide. According to exemplary embodiments, the substrate (111) may include Al2O3. According to exemplary embodiments, by providing a substrate (111) formed of aluminum oxide, the manufacturing cost of the LED package (100) can be reduced.

[0024] According to exemplary embodiments, the substrate (111) may include aluminum nitride. For example, the substrate (111) may include AlN.

[0025] According to exemplary embodiments, the substrate (111) may have a flat shape. According to exemplary embodiments, the substrate (111) may include a substantially flat upper surface (111T) and a lower surface (111B). The substrate (111) may include a first side (111S1), a second side (111S2), a third side (111S3), and a fourth side (111S4) interposed between the upper surface (111T) and the lower surface (111B). The first and third sides (111S1, 111S3) may be perpendicular to the X direction, and the second and fourth sides (111S2, 111S4) may be perpendicular to the Y direction.

[0026] According to exemplary embodiments, the Z-direction thickness (Z1) of the substrate (111) may be in the range of about 0.1 mm to 0.2 mm. According to exemplary embodiments, the Z-direction thickness (Z1) of the substrate (111) may be about 0.11 mm or more. According to exemplary embodiments, the Z-direction thickness (Z1) of the substrate (111) may be about 0.12 mm or more. According to exemplary embodiments, the Z-direction thickness (Z1) of the substrate (111) may be about 0.13 mm or more. According to exemplary embodiments, the Z-direction thickness (Z1) of the substrate (111) may be about 0.14 mm or more. According to exemplary embodiments, the Z-direction thickness (Z1) of the substrate (111) may be about 0.15 mm or more. According to exemplary embodiments, the Z-direction thickness (Z1) of the substrate (111) may be about 0.16 mm or more. According to exemplary embodiments, the Z-direction thickness (Z1) of the substrate (111) may be about 0.17 mm or more. According to exemplary embodiments, the Z-direction thickness (Z1) of the substrate (111) may be about 0.19 mm or more. According to exemplary embodiments, the Z-direction thickness (Z1) of the substrate (111) may be about 0.18 mm or more.

[0027] According to exemplary embodiments, by making the Z-direction thickness (Z1) of a substrate (111) composed of a material with relatively low thermal conductivity about 0.1 mm or more, the mechanical strength of the substrate (111) can be prevented from being excessively weakened.

[0028] According to exemplary embodiments, by making the Z-direction thickness (Z1) of a substrate (111) composed of a material with relatively low thermal conductivity 0.2 mm or less, an increase in the thermal resistance of the LED package (100) can be prevented, and accordingly, the heat dissipation efficiency of the LED package (100) can be improved. In addition, by reducing the length of the electrical path between the upper pads (112, 113) and the lower pads (114, 115), the driving voltage of the LED package (100) can be reduced. Furthermore, due to the reduction in the thickness of the substrate (111), solder stress occurring during the process of mounting the LED package (100) on a printed circuit board can be alleviated.

[0029] According to exemplary embodiments, the Z-direction thickness (Z2) of the upper pads (112, 113) may be in the range of about 0.06 mm to about 0.15 mm. According to exemplary embodiments, the Z-direction thickness (Z2) of the upper pads (112, 113) may be about 0.07 mm or more. According to exemplary embodiments, the Z-direction thickness (Z2) of the upper pads (112, 113) may be about 0.014 mm or less. According to exemplary embodiments, the Z-direction thickness (Z2) of the upper pads (112, 113) may be about 0.13 mm or less. According to exemplary embodiments, the Z-direction thickness (Z2) of the upper pads (112, 113) may be about 0.12 mm or less. According to exemplary embodiments, the Z-direction thickness (Z2) of the upper pads (112, 113) may be about 0.12 mm or less. According to exemplary embodiments, the Z-direction thickness (Z2) of the upper pads (112, 113) may be about 0.11 mm or less. According to exemplary embodiments, the Z-direction thickness (Z2) of the upper pads (112, 113) may be about 0.10 mm or less. According to exemplary embodiments, the Z-direction thickness (Z2) of the upper pads (112, 113) may be about 0.09 mm or less. According to exemplary embodiments, the Z-direction thickness (Z2) of the upper pads (112, 113) may be about 0.08 mm or less.

[0030] According to exemplary embodiments, by providing upper pads (112, 113) with a Z-direction thickness (Z2) of about 0.06 mm or more, the thickness of the portion of the side molding layer (140) interposed between the upper pads (112, 113) can be prevented from becoming excessively thin, thereby preventing cracks from occurring in the side molding layer (140). Additionally, since the ratio of the relative thickness of the upper pads (112, 113) to the substrate (111) is sufficiently large, the equivalent thermal resistance of the entire substrate (111) and upper pads (112, 113) can be reduced.

[0031] According to exemplary embodiments, by providing upper pads (112, 113) with a Z-direction thickness (Z2) of about 0.15 mm or less, the thickness of the LED package (100) can be prevented from becoming excessively thick and the manufacturing cost of the LED package (100) can be reduced.

[0032] According to exemplary embodiments, the Z-direction thickness (Z3) of the lower pads (114, 115, 116) may be in the range of about 0.06 mm to 0.15 mm. According to exemplary embodiments, the Z-direction thickness (Z3) of the lower pads (114, 115, 116) may be about 0.07 mm or more. According to exemplary embodiments, the Z-direction thickness (Z3) of the lower pads (114, 115, 116) may be about 0.14 mm or less. According to exemplary embodiments, the Z-direction thickness (Z3) of the lower pads (114, 115, 116) may be about 0.13 mm or less. According to exemplary embodiments, the Z-direction thickness (Z3) of the lower pads (114, 115, 116) may be about 0.12 mm or less. According to exemplary embodiments, the Z-direction thickness (Z3) of the lower pads (114, 115, 116) may be about 0.11 mm or less. According to exemplary embodiments, the Z-direction thickness (Z3) of the lower pads (114, 115, 116) may be about 0.10 mm or less. According to exemplary embodiments, the Z-direction thickness (Z3) of the lower pads (114, 115, 116) may be about 0.09 mm or less. According to exemplary embodiments, the Z-direction thickness (Z3) of the lower pads (114, 115, 116) may be about 0.08 mm or less.

[0033] According to exemplary embodiments, by providing lower pads (114, 115, 116) with a Z-direction thickness (Z3) of about 0.06 mm or more, it is possible to prevent cracks from occurring in the side molding layer (140) interposed between the lower pads (114, 115, 116) due to the thickness of the side molding layer (140) being excessively thin. Additionally, by making the relative thickness of the lower pads (114, 115, 116) with respect to the substrate (111) sufficiently large, the equivalent thermal resistance of the entire substrate (111) and lower pads (114, 115, 116) can be reduced.

[0034] According to exemplary embodiments, by providing lower pads (114, 115, 116) with a Z-direction thickness (Z3) of about 0.15 mm or less, the thickness of the LED package (100) can be prevented from becoming excessively thick and the manufacturing cost of the LED package (100) can be reduced.

[0035] The planar shape of the substrate (111), that is, the shape of the upper surface (111T) and the lower surface (111B), may be a chamfered rectangle. According to exemplary embodiments, the planar shape of the substrate (111), that is, the shape of the upper surface (111T) and the lower surface (111B), may be a rectangle with the corners removed. According to exemplary embodiments, the planar shape of the substrate (111), that is, the shape of the upper surface (111T) and the lower surface (111B), may be a cross shape. According to exemplary embodiments, the substrate (111) may have a rectangular flat shape with the corner portion between the first side (111S1) and the second side (111S2), the corner portion between the second side (111S2) and the third side (111S3), the corner portion between the third side (111S3) and the fourth side (111S4), and the corner portion between the third side (111S4) and the fourth side (111S4) removed. The corner portion of the substrate (111) may be removed to provide a passage for forming a side molding layer (140) in a molding process for manufacturing the LED package (111).

[0036] The upper pads (112, 113) and lower pads (114, 115, 116) may comprise a conductive material. According to exemplary embodiments, the upper pads (112, 113) and lower pads (114, 115, 116) may comprise a metal. According to exemplary embodiments, the upper pads (112, 113) and lower pads (114, 115, 116) may comprise copper (Cu).

[0037] Upper pads (112, 113) may be placed on the upper surface of the substrate (111), and lower pads (114, 115, 116) may be placed on the lower surface of the substrate (111). Through vias (not shown) penetrating the substrate (111) may connect the upper pad (112) and the lower pad (114), and may connect the upper pad (113) and the lower pad (115). When the LED package (100) is mounted on a printed circuit board such as a lighting device, the lower pads (114, 115) may be configured to be electrically connected to the printed circuit board.

[0038] The lower pad (116) can be insulated from the upper pads (112, 113). The lower pad (116) can be electrically floating. The lower pad (116) can be a thermally conductive pad to dissipate heat generated from the LED package (100).

[0039] An LED chip (120) can be mounted on a substrate (111). The LED chip (120) can be configured to be electrically connected to upper pads (112, 133). The anode of the LED chip (120) can be connected to the upper pad (112), and the cathode of the LED chip (120) can be connected to the upper pad (113). Accordingly, the upper pads (112, 113) and lower pads (114, 115) can provide a path for providing driving power to the LED chip (120).

[0040] The cathode of the LED chip (120) may be placed on the lower surface (120B) of the LED chip (120). The cathode of the LED chip (120) may form a eutectic bonding with the upper pad (113), or the cathode of the LED chip (120) may be connected to the upper pad (113) by soldering. The anode of the LED chip (120) may be formed on the upper surface (120T) of the LED chip (120). The anode of the LED chip (120) may be connected to the upper pad (112) by wirings (135).

[0041] A person skilled in the art will be able to easily arrive at an embodiment in which an anode and a cathode are each formed on the upper surface (120T) of an LED chip (120) and said anode and a cathode are connected to upper pads (112, 113) by wirings (135), and an anode and a cathode are each formed on the lower surface (120B) of an LED chip (120) and said anode and a cathode are connected to upper pads (112, 113) by either eutectic bonding or soldering, based on what is described herein.

[0042] The LED chip (120) may include a first conductivity semiconductor layer, an active layer, and a second conductivity semiconductor layer. According to exemplary embodiments, the first conductivity semiconductor layer is AlxInyGa1-x-yN (0 It may be composed of a single-crystal nitride having a composition of x≤1, 0≤y≤1, 0≤x+y≤1). The first conductivity semiconductor layer may be composed of a semiconductor doped with n-type impurities. According to exemplary embodiments, the first conductivity semiconductor layer may include GaN doped with Si, etc.

[0043] The active layer may be disposed on the first conductivity semiconductor layer. The active layer may emit light having a predetermined energy through the recombination of electrons and holes. According to exemplary embodiments, the active layer may include a multiple quantum well (MQW) structure in which quantum well layers (not shown) and quantum barrier layers (not shown) are alternately stacked. The thickness of each quantum well layer and quantum barrier layer may be in the range of about 3 nm to about 10 nm. According to exemplary embodiments, the multiple quantum well structure may include a multiple stacked structure of InGaN and GaN. However, it is not limited thereto, and according to exemplary embodiments, the active layer may be composed of a single quantum well (SQW) structure.

[0044] The second conductivity type semiconductor material layer is Al doped with p-type impurities. x In y Ga 1-x-y It may be composed of a single-crystal nitride having a composition of N (0≤x≤1, 0≤y≤1, 0≤x+y≤1). The p-type impurity may include, for example, Mg, but is not limited thereto.

[0045] The cathode of the Zener diode (131) may be configured to be electrically connected to the upper pad (112), and the anode of the Zener diode (131) may be configured to be electrically connected to the upper pad (113). The cathode of the Zener diode (131) may be connected to the upper pad (112) by wiring (136), and the anode of the Zener diode (131) may be connected to the upper pad (113) by either soldering or eutectic bonding.

[0046] A Zener diode (131) can be connected in parallel with an LED chip (120). The cathode of the Zener diode (131) can be substantially short-circuited with the anode of the LED chip (120), and the anode of the Zener diode (131) can be substantially short-circuited with the cathode of the LED chip (120). The Zener diode (131) can prevent damage to the LED chip (120) caused by reverse current and ESD (Electrostatic Discharge).

[0047] According to exemplary embodiments, the side molding layer (140) may include an insulating material. The side molding layer (140) may include SMC (Silicone Molding Compound).

[0048] According to exemplary embodiments, the side molding layer (140) may cover the upper surface of the substrate (111), the side of each of the upper pads (112, 113), and the side of each of the lower pads (114, 115, 116). According to exemplary embodiments, the side molding layer (140) may not cover the upper surface of each of the upper pads (112, 113) and the lower surface of each of the lower pads (114, 115, 116). According to exemplary embodiments, the side molding layer (140) may be spaced apart from the upper surface of the upper pads (112, 113) and the lower surface of the lower pads (114, 115, 116).

[0049] According to exemplary embodiments, the Z-direction thickness of the portion of the side molding layer (140) interposed between the upper pads (112, 113) may be substantially the same as the Z-direction thickness (Z2) of the upper pads (112, 113). According to exemplary embodiments, the Z-direction thickness of the portion of the side molding layer (140) interposed between the lower pads (114, 115, 116) may be substantially the same as the Z-direction thickness (Z3) of the lower pads (114, 115, 116).

[0050] According to exemplary embodiments, the side molding layer (140) may not cover the first to fourth sides (111S1, 111S2, 111S3, 111S4) of the substrate (111). According to exemplary embodiments, the side molding layer (140) may expose the first to fourth sides (111S1, 111S2, 111S3, 111S4) of the substrate (111). According to exemplary embodiments, the side molding layer (140) may be spaced apart from the first to fourth sides (111S1, 111S2, 111S3, 111S4) of the substrate (111). According to exemplary embodiments, the outer surface (140E) of the side molding layer (140) may be co-planar with the first to fourth sides (111S1, 111S2, 111S3, 111S4).

[0051] According to exemplary embodiments, the side molding layer (140) may include a cup portion (140C) that horizontally surrounds the LED chip (120) and the fluorescent layer (150). According to exemplary embodiments, the upper surface (140CT) of the cup portion (140C) of the side molding layer (140) may be spaced further away from the substrate (111) than the upper surface (150T) of the fluorescent layer (150). The inner surface (140CI) of the cup portion (140C) of the side molding layer (140) may be angled away from the LED chip (120) (i.e., outwardly).

[0052] A fluorescent layer (150) can be placed on an LED chip (120). The fluorescent layer (150) can cover a light-transmitting layer of the LED chip. According to exemplary embodiments, the fluorescent layer (150) can reduce the color dispersion of light generated by the LED chip (120).

[0053] The fluorescent layer (150) may include Phosphor-in-Glass (PiG). PiG may be a mixture of transparent glass and a ceramic phosphor. PiG may have high heat resistance and chemical resistance compared to conventional commercial fluorescent layers. Accordingly, the fluorescent layer (150) containing PiG can improve the reliability of the LED package (100) in an environment exposed to high temperatures and humidity due to the high output of the LED chip (120).

[0054] The reflective molding layer (160) can fill a portion of the space defined by the cup portion (140C) of the side molding layer (140). Accordingly, the reflective molding layer (160) can be horizontally surrounded by the cup portion (140C) of the side molding layer (140). The reflective molding layer (160) may include an insulating material. The reflective molding layer (160) may include white silicon and TiN particles embedded in the white silicon. The reflective molding layer (160) can reflect light generated by the LED chip (120) to improve the light extraction efficiency of the LED package (100).

[0055] According to exemplary embodiments, the upper surface (160T) of the reflective molding layer (160) may be oblique to the upper surface (111T) of the substrate (111). According to exemplary embodiments, the upper surface (160T) of the reflective molding layer (160) may be inclined to be lower (i.e., closer to the substrate (111)) as it approaches horizontally from the cup portion (140C) of the side molding layer (140) toward the fluorescent layer (150). Alternatively, the upper surface (160T) of the reflective molding layer (160) may be raised as it approaches from the LED chip (120) toward the cup portion (140C) of the side molding layer (140).

[0056] Since the upper surface (140CT) of the cup portion (140C) of the side molding layer (140) is spaced further away from the substrate (111) than the upper surface (150T) of the fluorescent layer (150), it is possible to form an upper surface slope of the upper surface (160T) of the reflective molding layer (160) such that the upper surface (160T) of the reflective molding layer (160) becomes higher as it approaches the cup portion (140C) of the side molding layer (140) from the LED chip (120).

[0057] According to exemplary embodiments, the reflective molding layer (160) may cover upper pads (112, 113), an LED chip (120), a Zener diode (131), and wirings (135, 136). According to exemplary embodiments, the reflective molding layer (160) may cover a portion of the upper surface of the upper pads (112, 113), a portion of the side and upper surface (120T) of the LED chip (120).

[0058] According to exemplary embodiments, the reflective molding layer (160) may expose the upper surface (150T) of the fluorescent layer (150). According to exemplary embodiments, the reflective molding layer (160) may be spaced apart from the upper surface (150T) of the fluorescent layer (150).

[0059] According to exemplary embodiments, the reflective molding layer (160) may partially cover the side (150S) of the fluorescent layer (150). According to exemplary embodiments, the reflective molding layer (160) may cover the lower part of the side (150S) of the fluorescent layer (150) and expose the upper part of the side (150S) of the fluorescent layer (150). According to exemplary embodiments, the reflective molding layer (160) may come into contact with the lower part of the side (150S) of the fluorescent layer (150).

[0060] According to exemplary embodiments, the reflective molding layer (160) may expose a portion of the side (150S) of the fluorescent layer (150). According to exemplary embodiments, the reflective molding layer (160) may be spaced apart from a portion of the side (150S) of the fluorescent layer (150).

[0061] According to exemplary embodiments, the height (150EH) of the exposed portion (i.e., the portion not covered by the reflective molding layer (160)) of the side (150S) of the fluorescent layer (150) may be in the range of 0.1% to 100% of the height (150H) of the fluorescent layer (150). In this case, when the height (150EH) is 100% of the height (150H) of the fluorescent layer (150), the reflective molding layer (160) does not cover the side (150S) of the fluorescent layer (150), so the entire side (150S) of the fluorescent layer (150) may be exposed.

[0062] According to exemplary embodiments, the height (150EH) may be 5% or more of the height (150H). According to exemplary embodiments, the height (150EH) may be 10% or more of the height (150H). According to exemplary embodiments, the height (150EH) may be 15% or more of the height (150H). According to exemplary embodiments, the height (150EH) may be 20% or more of the height (150H). According to exemplary embodiments, the height (150EH) may be 25% or more of the height (150H). According to exemplary embodiments, the height (150EH) may be 30% or more of the height (150H). According to exemplary embodiments, the height (150EH) may be 35% or more of the height (150H). According to exemplary embodiments, the height (150EH) may be 40% or more of the height (150H). According to exemplary embodiments, the height (150EH) may be 45% or more of the height (150H). According to exemplary embodiments, the height (150EH) may be 50% or more of the height (150H).

[0063] According to exemplary embodiments, the height (150EH) may be 95% or less of the height (150H). According to exemplary embodiments, the height (150EH) may be 90% or less of the height (150H). According to exemplary embodiments, the height (150EH) may be 85% or less of the height (150H). According to exemplary embodiments, the height (150EH) may be 80% or less of the height (150H). According to exemplary embodiments, the height (150EH) may be 75% or less of the height (150H). According to exemplary embodiments, the height (150EH) may be 70% or less of the height (150H). According to exemplary embodiments, the height (150EH) may be 65% or less of the height (150H). According to exemplary embodiments, the height (150EH) may be 60% or less of the height (150H). According to exemplary embodiments, the height (150EH) may be 55% or less of the height (150H).

[0064] According to exemplary embodiments, the height (150CH) of the portion of the side (150S) of the fluorescent layer (150) covered by the reflective molding layer (160) may be in the range of 0% to 99.9% of the height (150CH) of the fluorescent layer (150).

[0065] According to exemplary embodiments, the height (150CH) may be 5% or more of the height (150H). According to exemplary embodiments, the height (150CH) may be 10% or more of the height (150H). According to exemplary embodiments, the height (150CH) may be 15% or more of the height (150H). According to exemplary embodiments, the height (150CH) may be 20% or more of the height (150H). According to exemplary embodiments, the height (150CH) may be 25% or more of the height (150H). According to exemplary embodiments, the height (150CH) may be 30% or more of the height (150H). According to exemplary embodiments, the height (150CH) may be 35% or more of the height (150H). According to exemplary embodiments, the height (150CH) may be 40% or more of the height (150H). According to exemplary embodiments, the height (150CH) may be 45% or more of the height (150H).

[0066] According to exemplary embodiments, the height (150CH) may be 95% or less of the height (150H). According to exemplary embodiments, the height (150CH) may be 90% or less of the height (150H). According to exemplary embodiments, the height (150CH) may be 85% or less of the height (150H). According to exemplary embodiments, the height (150CH) may be 80% or less of the height (150H). According to exemplary embodiments, the height (150CH) may be 75% or less of the height (150H). According to exemplary embodiments, the height (150CH) may be 70% or less of the height (150H). According to exemplary embodiments, the height (150CH) may be 65% or less of the height (150H). According to exemplary embodiments, the height (150CH) may be 60% or less of the height (150H). According to exemplary embodiments, the height (150CH) may be 55% or less of the height (150H). According to exemplary embodiments, the height (150CH) may be 50% or less of the height (150H).

[0067] When the reflective molding layer (160) completely covers the side (150S) of the fluorescent layer (150), the light-emitting surface area of ​​the LED package (100) is equal to the upper surface area of ​​the fluorescent layer (150). For example, when the upper surface of the fluorescent layer (150) has a length (150X) in the X direction and a length (150Y) in the Y direction and the side (150S) of the fluorescent layer (150) is completely covered by the reflective molding layer (160), the light-emitting surface (LES) of the LED package is equal to the following Equation 1.

[0068] [Equation 1]

[0069]

[0070] According to exemplary embodiments, since the reflective molding layer (160) partially exposes the side (150S) of the fluorescent layer (150), light generated by the LED chip (120) can be emitted further from the exposed side (150S) in addition to the upper surface (150T) of the fluorescent layer (150). The LES of the LED package (100) according to exemplary embodiments is given by Equation 2 below.

[0071] [Equation 2]

[0072]

[0073] According to exemplary embodiments, the LES of the LED package (100) can be increased, and thereby, an LED package (100) with improved light extraction efficiency can be provided.

[0074] It was confirmed that the light extraction efficiency of the experimental example LED package, where the height (150EH) is 40% of the height (150H), is about 2% better than the light extraction efficiency of the comparative example LED package, where the height (150EH) is 0% of the height (150H) (i.e., the side (150S) of the fluorescent layer (150) is completely covered by the reflective molding layer (160).

[0075] FIG. 3a is a perspective view showing an LED package (101) according to other exemplary embodiments.

[0076] FIG. 3b is a perspective view showing the substrate (111'), upper pads (112, 113) and lower pads (115, 116) of an LED package (101).

[0077] FIG. 3c is a side view of the LED package (101) of FIG. 3a.

[0078] Referring to FIGS. 3a through 3c, the LED package (101) may include a substrate (111'), upper pads (112, 113), lower pads (114, 115, 116, see FIG. 2c), an LED chip (120, see FIG. 2d), a Zener diode (131, see FIG. 2d), wiring (135, 136, see FIG. 2d), a side molding layer (140'), a fluorescent layer (150), and a reflective molding layer (160).

[0079] The upper pads (112, 113), lower pads (114, 115, 116, see FIG. 2c), LED chip (120, see FIG. 2d), Zener diode (131, see FIG. 2d), wiring (135, 136, see FIG. 2d), fluorescent layer (150) and reflective molding layer (160) are substantially the same as those described with reference to FIG. 1a through 2d, so a redundant description of them is omitted.

[0080] The substrate (111') may include an upper surface (111T') perpendicular to the Z direction, a lower surface (111B') perpendicular to the Z direction, a first side surface (111S1') perpendicular to the X direction, a second side surface (111S2') perpendicular to the Y direction, a third side surface (111S3') perpendicular to the X direction, and a fourth side surface (111S4') perpendicular to the Y direction.

[0081] Except for the fact that recesses (111R) are formed in the first to fourth sides (111S1', 111S2', 111S3', 111S4') and the corner portion is not removed, the substrate (111') is generally similar to the substrate (111) described with reference to FIGS. 1a to 2d.

[0082] According to exemplary embodiments, the recesses (111R) may be half of a circular hole. According to exemplary embodiments, the recesses (111R) may be formed with a hole for injecting molding material during a molding process for forming a side molding layer (140') of an LED package (101).

[0083] According to exemplary embodiments, the first and second sides (111S1', 111S2') may include inner surfaces (111S1I, 111S2I) defining a recess (111R). Although not explicitly illustrated, the third and fourth sides (111S3', 111S4') may also include inner surfaces defining a recess (111R). According to exemplary embodiments, the shape of the upper surface (111T') and the lower surface (111B') of the substrate (111'), respectively, may be a rectangle with a concave portion formed at the edge.

[0084] According to exemplary embodiments, the side molding layer (140') is substantially the same as the side molding layer (140) described with reference to FIGS. 1a through 2d, except that it fills the recesses (111R) to form a co-plane with the first to fourth sides (111S1', 111S2', 111S3', 111S4') of the substrate (111').

[0085] FIG. 4a is a perspective view showing an LED package (102) according to other exemplary embodiments.

[0086] FIG. 4b is a side view of the LED package (102) of FIG. 4a.

[0087] Referring to FIGS. 4a and 4b, the LED package (102) may include a substrate (111), upper pads (112, 113, see FIG. 1c), lower pads (114, 115, 116, see FIG. 2c), an LED chip (120, see FIG. 2d), a Zener diode (131, see FIG. 2d), wiring (135, 136, see FIG. 2d), a side molding layer (141), a lower molding layer (142), a fluorescent layer (150), and a reflective molding layer (160).

[0088] The upper pads (112, 113, see FIG. 1c), lower pads (114, 115, 116, see FIG. 2c), LED chip (120, see FIG. 2d), Zener diode (131, see FIG. 2d), wiring (135, 136, see FIG. 2d), fluorescent layer (150) and reflective molding layer (160) are substantially the same as those described with reference to FIG. 1a through 2d, so a redundant description of them is omitted.

[0089] According to exemplary embodiments, the side molding layer (141) is substantially identical to the portion of the side molding layer (140) of FIGS. 1a to 2d located on the upper surface (111T) of the substrate (111). According to exemplary embodiments, the lower molding layer (142) is substantially identical to the portion of the side molding layer (140) of FIGS. 1a to 2d located on the lower surface (111B) of the substrate (111).

[0090] Unlike the substrate (111) of FIGS. 1a through 2d, the substrate (111) may not include removed corner portions. Accordingly, the side molding layer (141) and the bottom molding layer (142) may be separated from each other. The side molding layer (141) and the bottom molding layer (142) may be spaced apart from each other with the substrate (111) in between. Accordingly, the outer surfaces of the side molding layer (141) and the bottom molding layer (142) may co-plane with the first to fourth sides (111S1, 111S2, 111S3, 111S4) of the substrate (111). According to exemplary embodiments, the side molding layer (141) and the bottom molding layer (142) may be provided by a separate molding process.

[0091] FIG. 5a is a perspective view showing an LED package (103) according to other exemplary embodiments.

[0092] FIG. 5b is a side view of the LED package (103) of FIG. 5a.

[0093] Referring to FIGS. 5A and 5B, the LED package (103) may include a substrate (111), upper pads (112, 113, see FIG. 1C), lower pads (114, 115, 116, see FIG. 2C), an LED chip (120, see FIG. 2D), a Zener diode (131, see FIG. 2D), wiring (135, 136, see FIG. 2D), a side molding layer (141), a fluorescent layer (150), and a reflective molding layer (160).

[0094] The upper pads (112, 113, see FIG. 1c), lower pads (114, 115, 116, see FIG. 2c), LED chip (120, see FIG. 2d), Zener diode (131, see FIG. 2d), wiring (135, 136, see FIG. 2d), fluorescent layer (150) and reflective molding layer (160) are substantially the same as those described with reference to FIG. 1a through 2d, so a redundant description of them is omitted.

[0095] According to exemplary embodiments, the substrate (111) and the side molding layer (141) are substantially the same as those described with reference to FIGS. 4a and 4b. According to exemplary embodiments, the LED package (103) may not include a lower molding layer (142), and accordingly, the sides of the lower pads (114, 115, 116, see FIG. 2c) may be exposed.

[0096] FIG. 6a is a perspective view showing an LED package (104) according to exemplary embodiments.

[0097] FIG. 6b is a plan view of an LED package (104) according to exemplary embodiments.

[0098] FIG. 6c is a side view of an LED package (100) according to exemplary embodiments.

[0099] FIG. 6d is a cross-sectional view taken along the cutting line II-II' of FIG. 6a.

[0100] Referring to FIGS. 6a through 6d, the LED package (104) may include a substrate (111), upper pads (112, 113, see FIG. 1c), lower pads (114, 115, 116, see FIG. 2c), an LED chip (120), a Zener diode (131), wiring (135, 136, see FIG. 2d), a side molding layer (140), a fluorescent layer (150), a reflective molding layer (160), and a cell lens (170).

[0101] The substrate (111), upper pads (112, 113, see FIG. 1c), lower pads (114, 115, 116, see FIG. 2c), LED chip (120), Zener diode (131), wiring (135, 136, see FIG. 2d), side molding layer (140), fluorescent layer (150) and reflective molding layer (160) are substantially the same as those described with reference to FIG. 1a through 2d, so a redundant description of them is omitted.

[0102] According to exemplary embodiments, the cell lens (170) can change the light distribution characteristics of the LED package (100). According to exemplary embodiments, the cell lens (170) can improve the light extraction efficiency of the LED package (100) by refracting light directed outward from the intended directional angle. According to experimental examples, it was confirmed that the light extraction efficiency of the LED package (104) was improved by about 3% by the formation of the cell lens (170).

[0103] According to exemplary embodiments, the cell lens (170) may be a convex lens. According to exemplary embodiments, the cell lens (170) may cover a portion of the fluorescent layer (150) and the reflective molding layer (160). According to exemplary embodiments, the cell lens (170) may cover the entire fluorescent layer (150). According to exemplary embodiments, the area of ​​the cell lens (170) may be larger than the area of ​​the reflective molding layer (160). According to exemplary embodiments, the optical axis of the cell lens (170) may pass through the horizontal center (i.e., the center in the X and Y directions) of the fluorescent layer (150), but is not limited thereto.

[0104] FIG. 7a is a cross-sectional view illustrating an LED package (105) according to exemplary embodiments, showing a portion corresponding to FIG. 6d.

[0105] Referring to FIG. 7a, the LED package (105) may include a substrate (111), upper pads (112, 113, see FIG. 1c), lower pads (114, 115, 116, see FIG. 2c), an LED chip (120), a Zener diode (131), wiring (135, 136, see FIG. 2d), a side molding layer (140), a fluorescent layer (150), a reflective molding layer (160), and a cell lens (171).

[0106] The substrate (111), upper pads (112, 113, see FIG. 1c), lower pads (114, 115, 116, see FIG. 2c), LED chip (120), Zener diode (131), wiring (135, 136, see FIG. 2d), side molding layer (140), fluorescent layer (150) and reflective molding layer (160) are substantially the same as those described with reference to FIG. 1a through 2d, so a redundant description of them is omitted.

[0107] According to exemplary embodiments, the cell lens (171) is similar to the cell lens (170) of FIG. 6d, but may cover only a portion of the fluorescent layer (150). According to exemplary embodiments, the cell lens (171) may not cover the reflective molding layer (160). According to exemplary embodiments, the cell lens (171) may not overlap perpendicularly (i.e., in the Z direction) with the reflective molding layer (160). According to exemplary embodiments, the area of ​​the cell lens (171) may be smaller than the area of ​​the light-transmitting layer (160).

[0108] FIG. 7b is a cross-sectional view illustrating an LED package (106) according to exemplary embodiments, showing a portion corresponding to FIG. 6d.

[0109] Referring to FIG. 7b, the LED package (106) may include a substrate (111), upper pads (112, 113, see FIG. 1c), lower pads (114, 115, 116, see FIG. 2c), an LED chip (120), a Zener diode (131), wiring (135, 136, see FIG. 2d), a side molding layer (140), a fluorescent layer (150), a reflective molding layer (160), and a cell lens (172).

[0110] The substrate (111), upper pads (112, 113, see FIG. 1c), lower pads (114, 115, 116, see FIG. 2c), LED chip (120), Zener diode (131), wiring (135, 136, see FIG. 2d), side molding layer (140), fluorescent layer (150) and reflective molding layer (160) are substantially the same as those described with reference to FIG. 1a through 2d, so a redundant description of them is omitted.

[0111] According to exemplary embodiments, the cell lens (172) is similar to the cell lens (170) of FIG. 6d, but can cover the entire fluorescent layer (150) and the reflective molding layer (160).

[0112] FIG. 8 is a flowchart illustrating a method for manufacturing an LED package according to exemplary embodiments.

[0113] FIGS. 9a to 9e are cross-sectional views illustrating a method for manufacturing an LED package according to exemplary embodiments.

[0114] Referring to FIG. 1c, FIG. 8 and FIG. 9a, in P10, upper pads (112, 113) and lower pads (114, 115, 116) can be formed on a substrate layer (111L). The substrate layer (111L) can provide a base for forming an LED package (100, see FIG. 1) before separation. The substrate layer (111L) may be a large-area substrate for manufacturing a plurality of LED packages (100, see FIG. 1) simultaneously.

[0115] Next, referring to FIGS. 8 and FIGS. 9b, a side molding layer (140L) can be formed in P20. According to exemplary embodiments, the side molding layer (140L) can cover the sides of the upper pads (112, 113, see FIG. 1c) and expose the upper surface, and cover the sides of the lower pads (114, 115, 116, see FIG. 1c) and expose the upper surface.

[0116] The side molding layer (140L) horizontally surrounds the upper pads (112, 113, see FIG. 1c) and may include a cup portion protruding from the upper surface of the substrate layer (111L) above the upper pads (112, 113, see FIG. 1c). The cup portion of the side molding layer (140L) may be for forming the cup portion (140C) of the side molding layer (140, see FIG. 2d).

[0117] Referring to FIG. 1b, FIG. 8 and FIG. 9c, in P30, an LED chip (120), a Zener diode (131), wirings (135, 136) and a fluorescent layer (150) may be provided. According to exemplary embodiments, the LED chip (120) and the Zener diode (131) may be provided by a surface mounting technique.

[0118] Referring to FIGS. 8 and 9d, a reflective molding layer (160) can be formed in P40. The reflective molding layer (160) can fill the space defined by the cup portion of the side molding layer (140L). The reflective molding layer (160) can be formed, for example, by dispensing or dotting white silicone. According to exemplary embodiments, by providing a smaller amount of white silicone as it approaches the fluorescent layer (150) from the side molding layer (140L), the upper surface of the reflective molding layer (160) can be sloped so that it becomes lower as it approaches the fluorescent layer (150) from the side molding layer (140L).

[0119] Next, referring to FIGS. 1a, FIGS. 8 and FIGS. 9e, the LED package (100) can be individualized. According to exemplary embodiments, the LED packages (100) can be individualized by cutting the molding layer (140L) and the substrate layer (111L) with a blade (BL).

[0120] As described above, exemplary embodiments have been disclosed in the drawings and specification. Although specific terms have been used to describe the embodiments in this specification, they are used only for the purpose of explaining the technical concept of this disclosure and are not intended to limit the meaning or the scope of this disclosure as defined in the claims. Therefore, those skilled in the art will understand that various modifications and equivalent alternative embodiments are possible therefrom. Accordingly, the true technical scope of protection of this disclosure should be determined by the technical concept of the appended claims.

Claims

Claim 1 An LED package comprising: a substrate including an insulating material; upper pads disposed on the upper surface of the substrate; a side molding layer covering the upper surface of the substrate and the sides of the upper pads; a light-emitting diode (LED) chip disposed on the upper surface of the substrate and configured to be electrically connected to the upper pads; a fluorescent layer disposed on the LED chip; and a reflective molding layer covering the LED chip and disposed on the substrate, comprising white silicon, wherein the reflective molding layer exposes at least a portion of the sides of the fluorescent layer, the portion of the fluorescent layer exposed by the reflective molding layer is exposed in an empty space, and the vertical level of the highest point on the upper surface of the reflective molding layer is higher than the vertical level of the upper surface of the fluorescent layer. Claim 2 An LED package according to claim 1, characterized in that the upper surface of the reflection molding layer is oblique with respect to the upper surface of the substrate. Claim 3 An LED package according to claim 1, characterized in that the upper surface of the reflection molding layer moves further away from the upper surface of the substrate as it moves horizontally away from the LED chip. Claim 4 The LED package according to claim 1, wherein the side molding layer comprises a cup portion that horizontally surrounds the LED chip and the fluorescent layer. Claim 5 An LED package according to claim 4, characterized in that the upper surface of the cup portion is spaced further away from the substrate than the upper surface of the fluorescent layer. Claim 6 An LED package according to claim 4, characterized in that the inner surface of the side molding layer facing the LED chip is inclined in a direction away from the LED chip with respect to the upper surface of the substrate. Claim 7 An LED package according to claim 1, characterized in that the lower part of the fluorescent layer is covered by the reflective molding layer, and the upper part of the fluorescent layer is spaced apart from the reflective molding layer. Claim 8 An LED package according to claim 1, characterized in that the height of the portion of the fluorescent layer exposed by the reflective molding layer is in the range of 0.1% to 100% of the total height of the fluorescent layer. Claim 9 An LED package according to claim 1, characterized in that some of the light generated by the LED chip is emitted to the outside from the side of the fluorescent layer. Claim 10 An LED package comprising: a substrate; lower pads disposed on the lower surface of the substrate; upper pads disposed on the upper surface of the substrate; an LED chip disposed on the upper surface of the substrate and configured to be electrically connected to the upper pads; a fluorescent layer disposed on the LED chip; a reflective molding layer covering the LED chip and disposed on the substrate, comprising white silicon; and a side molding layer covering the upper surface of the substrate, the side of the upper pads and the lower surface of the lower pads, and including a cup portion that horizontally surrounds the LED chip, the fluorescent layer and the reflective molding layer, wherein the upper surface of the cup portion is spaced further away from the substrate than the upper surface of the fluorescent layer, and the inner surface of the side molding layer facing the LED chip is obliquely inclined with respect to the upper surface of the substrate in a direction away from the LED chip, the portion of the fluorescent layer exposed by the reflective molding layer is exposed in an empty space, and the vertical level of the highest point on the upper surface of the reflective molding layer is higher than the vertical level on the upper surface of the fluorescent layer.

Images