LED package structure

Abstract

This invention discloses an LED package structure. The structure includes a first pad structure and a second pad structure that are electrically connected to the two electrodes of an LED chip, respectively, with the first and second pad structures insulated from each other, and the dimensions of the first and second pad structures are such that they are electrically connected to the first and second polar electrodes of the LED chip, respectively, and the sum of the bottom areas of the first and second pad structures is 0.3 to 1 times the bottom area of ​​the LED chip package. This solution increases the contact area between the chip and the substrate pads and increases the tolerance for placement errors by growing a larger area pad structure under small chip electrodes, thereby enabling the direct use of CSP (Chip Scale Package) without introducing a conductive board and improving the yield rate of mounted (SMD) products.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and particularly to an LED package structure.

Background Art

[0002] Micro LED (Mini / Micro LED) is a type of new display technology, composed of millions of tiny LEDs, and each LED can emit light independently. With this structure, Micro LED can provide higher contrast and a wider color gamut. Furthermore, Micro LED displays have higher brightness and a faster refresh rate, and exhibit better performance in the display of moving images. Compared with conventional LCD displays, Micro LED displays do not require a backlight because each LED can emit light independently. As a result, Micro LED displays can better control the brightness of each pixel and provide higher contrast and more realistic colors. Compared with OLED displays, Micro LED displays have higher brightness and a longer lifespan because LED materials do not deteriorate while OLED materials do over time.

[0003] However, Micro LED currently faces several technical bottlenecks, one of which is the low packaging efficiency and yield. The chip size adopted for Micro LED is extremely small, and its electrode area is correspondingly small. In the packaging process, it is difficult to perform very precise control on the Micro LED chip to achieve accurate connection between the chip electrodes and the substrate pads, and it is difficult to ensure that each LED is correctly placed.

Summary of the Invention

Problems to be Solved by the Invention

[0004] The objective of the present invention is to provide an LED package structure that improves the accuracy of microchip pad placement on a substrate and enhances packaging efficiency and yield rate by increasing the area of ​​the chip pad and improving the chip pad structure and the electrode structure directly connected to the pad. [Means for solving the problem]

[0005] This invention is realized through the following technical solutions.

[0006] The present invention provides an LED package structure. The LED package structure includes an LED chip, a fluorescent film covering the upper surface of the LED chip, a pad structure provided on the lower surface of the LED chip, a first reflective layer covering the sidewall of the LED chip, and a second reflective layer covering the sidewall of the LED pad structure. The pad structure includes a first pad electrically connected to the first electrode of the LED chip and a second pad connected to the second electrode of the LED chip, with the first and second pads insulated from each other, and the sum of the bottom areas of the pad structure is 0.3 to 1 times the bottom area of ​​the LED chip package structure.

[0007] Furthermore, the first and / or second electrodes of the LED chip are made of multilayer metal, and are arranged in the following order from the end closest to the LED chip to the end closest to the pad structure: Ti layer, Cu layer, Ni layer, Au layer, or Cr layer, Cu layer, Ni layer, Au layer, in that order.

[0008] Furthermore, the thickness of the first electrode and / or the second electrode is 1 μm to 100 μm, of which the thickness of the Ti layer or Cr layer is 100 Å to 5000 Å, the thickness of the Cu layer is 1 μm to 100 μm, the thickness of the Ni layer is 1 μm to 10 μm, and the thickness of the Au layer is 200 Å to 5000 Å.

[0009] Furthermore, the aforementioned First pad and Second padIt includes an upper metal layer close to the LED chip and a lower metal layer far from the LED chip, wherein the upper metal layer is a Cu metal layer and the lower metal layer is an Au metal layer, a Sn metal layer, or a SnAg alloy layer.

[0010] Furthermore, the thickness of the upper metal layer is 1 μm to 100 μm, and the thickness of the lower metal layer is 1 μm to 100 μm. and / or, a Cr or Ti adhesive metal layer is further provided between the upper metal layer and the LED chip (2), and the thickness of the adhesive metal layer is 100 Å to 5000 Å. and / or, a Ni or Pt barrier layer is further provided between the upper metal layer and the lower metal layer, and the thickness of the barrier layer is 1 μm to 10 μm. and / or, the lower metal layer is a SnAg alloy layer, of which the Ag content is 0.5% to 3.5%.

[0011] Furthermore, a first through groove is provided in the first pad that does not communicate with the first electrode, and / or a second through groove is provided in the second pad that does not communicate with the second electrode.

[0012] Furthermore, the patterns and / or sizes of the first through groove and the second through groove are different and used to distinguish the first pad from the second pad. The area of ​​the first through groove occupies 0% to 15% of the area of ​​the first pad, and / or the area of ​​the second through groove occupies 0% to 15% of the area of ​​the second pad.

[0013] Furthermore, the distance D2 between the first pad and the second pad is less than or equal to the distance D1 between the first electrode and the second electrode, and D2 ≥ 150 μm.

[0014] Furthermore, the upper end of the first reflective layer is higher than the lower surface of the LED chip, and its lower end is flush with the lower surface of the LED chip. The upper end of the second reflective layer is flush with the lower surface of the LED chip, and its lower end is flush with the lower surface of the pad structure.

[0015] Furthermore, the width of the fluorescent film (1) is greater than the width of the LED chip (2), and the width of the fluorescent film is less than the width of the first reflective layer (4), and the top surface of the first reflective layer and the top surface of the fluorescent film (1) are flush. and / or, the width of the fluorescent film (1) is greater than the width of the LED chip (2), and the top surface of the first reflective layer (4) and the upper surface of the LED chip (2) are flush, and the fluorescent film (1) covers the upper surface of the LED chip (2) and the top surface of the first reflective layer (4). and / or, the width of the fluorescent film (1) is greater than the width of the LED chip (2), and the fluorescent film (1) covers the upper surface of the LED chip (2) and encloses a part of the side surface of the LED chip (2), and the top surface of the first reflective layer (4) and the bottom of the side surface of the fluorescent film (1) are flush.

[0016] Furthermore, the width of the fluorescent film is greater than the width of the LED chip, the fluorescent film covers the upper surface of the LED chip and encloses a portion of the side surface of the LED chip, and the top surface of the first reflective layer and the bottom surface of the side surface of the fluorescent film are flush.

[0017] Furthermore, a cup structure (5) is provided between the first reflective layer (4) and the LED chip (2), and the cup structure (5) is provided on the surrounding side wall of the LED chip (2). [Effects of the Invention]

[0018] The present invention has the following advantages compared to the prior art.

[0019] Existing chip electrode dimensions are excessively small, making direct SMD mounting and use relatively difficult, and typically requiring lead frame packaging. This solution increases the contact area between the chip and the conductive substrate by growing a larger area pad structure beneath the small chip electrode, thereby increasing the tolerance for placement errors. This enables direct use of CSP without the need for a lead frame and improves the rate of good mounted products.

[0020] When the area difference between the pad structure and the LED electrode is enlarged, the stress between the pad structure and the first-layer reflective encapsulation layer increases. Therefore, it is necessary to control the area of the pad structure. By grooving the pad structure, the stress can be effectively relieved and the risk of detachment can be reduced. At the same time, by designing grooves of different shapes, it can be used to distinguish the positive and negative electrodes of the LED.

[0021] The second-layer reflective encapsulation layer covers the pad structure and plays a role in protecting the stability of the enlarged pad structure.

Brief Description of the Drawings

[0022] [Figure 1] It is a schematic diagram of the LED package structure in Example 1. [Figure 2] It is a schematic diagram of the LED chip structure in Example 1. [Figure 3] It is a schematic diagram of the bottom view of Figure 1. [Figure 4] It is a schematic diagram of the LED package structure in Example 2. [Figure 5] It is a schematic diagram of the LED package structure in Example 3. [Figure 6] It is a schematic diagram of the first pad and the second pad growth regions of the LED package structure in Example 4. [Figure 7] It is a schematic diagram of the first pad and the second pad growth regions of the LED package structure in Example 5.

Description of the Reference Signs

[0023] 1: Fluorescent film; 2: LED chip; 2a: Top surface; 2b: Bottom surface; 2c: Side wall; 210: Substrate; 211: N-type semiconductor layer; 212: Multiple quantum well layer; 213: P-type semiconductor layer; 214: N electrode; 2141: First N electrode; 2142: Second N electrode; 215: P electrode; 2151: First P electrode; 2152: Second P electrode; 216: Insulating layer; 217: Conductive layer; 3: Electrode; 4: First reflective layer; 5: Cup structure (Bowl cup structure); 6.1: First pad; 6.11: First through groove; 6.2: Second pad; 6.21: Second through groove; 7: Second reflective layer. [Modes for carrying out the invention]

[0024] The technical solutions of the present invention will be described clearly and completely below with reference to the drawings. Obviously, the embodiments described are some embodiments of the present invention, not all embodiments. All other embodiments that can be obtained by those skilled in the art without creative work based on the embodiments of the present invention are all within the scope of the present invention.

[0025] In the description of this invention, the directions or positional relationships indicated by terms such as "center," "up," "down," "left," "right," "vertical," "horizontal," "inside," and "outside" are based on the directions or positional relationships shown in the drawings and are used solely to facilitate and simplify the explanation of this invention. They do not indicate or imply that the indicated device or element has a specific orientation or must be configured and operated in a specific orientation, and should not be understood as limiting the invention. Furthermore, the terms "first," "second," and "third" are used solely for illustrative purposes and should not be understood as indicating or implying relative importance.

[0026] This invention is realized through the following technical solutions. Example 1 As shown in the schematic diagram of the LED package structure in Figure 1, it includes an LED chip 2, a fluorescent film 1, a pad structure 6, a first reflective layer 4, and a second reflective layer 7. The LED chip 2, as a light-emitting unit, has an upper surface 2a and a lower surface 2b facing each other, a side wall 2c connecting the upper surface 2a and the lower surface 2b, and a first electrode 3.1 and a second electrode 3.2 located on the lower surface and separated from each other. The polarity of the first electrode 3.1 and the second electrode 3.2 are opposite. That is, if the first electrode 3.1 is a P-type electrode, the second electrode 3.2 is an N-type electrode, and if the first electrode 3.1 is an N-type electrode, the second electrode 3.2 is a P-type electrode. The number of first electrodes 3.1 and second electrodes 3.2 may be one or multiple, depending on the design. The fluorescent film 1 is provided on the upper surface (i.e., the light-emitting surface) of the LED chip 2 and is used to convert at least some of the wavelengths of the light emitted by the LED chip 2 to other wavelengths. The first reflective layer 4 covers the sidewall 2c of the LED chip and exposes at least a portion of the bottom surface of the first electrode 3.1 and at least a portion of the bottom surface of the second electrode 3.2. The pad structure 6 includes a first pad 6.1 electrically connected to the first electrode 3.1 and a second pad 6.2 electrically connected to the second electrode 3.2. In horizontal projection, the shapes of the first pad 6.1 and the second pad 6.2 are identical and larger than the areas of the first electrode 3.1 and the second electrode 3.2, respectively. Figure 3 shows a schematic diagram of the bottom view structure of the LED package structure. The second reflective layer 7 covers the sidewalls of the first pad 6.1 and the second pad 6.2 and exposes at least a portion of the bottom surface of the first pad 6.1 and at least a portion of the bottom surface of the second pad 6.2.

[0027] More specifically, Figure 2 shows a schematic diagram of the structure of the LED chip 2, which is a type of flip-chip LED chip 2 and includes an N-type semiconductor layer 211, a multiple quantum well layer 212, a P-type layer 213, and N electrodes 214 and P electrodes 215 that are electrically connected to the N-type and P-type semiconductor layers, respectively. The first electrode 3.1 and the second electrode 3.2 are each electrically connected to either the N electrode 214 or the P electrode 215. In the manufacturing process of the N electrode 214 and the P electrode 215, they are each formed by multiple steps, and further multiple N electrodes and multiple P electrodes can be formed. In this embodiment, the N electrode 214 includes electrically connected first N electrode 2141 and second N electrode 2142, and the P electrode includes electrically connected first P electrode 2151 and second P electrode 2152. It also includes an insulating layer 216 that insulates the N electrode 214 and the P electrode 215 from each other, and a conductive layer 217 provided between the P electrode 215 and the P-type semiconductor layer. Typically, the first N electrode 2141 and the first P electrode 2151 are dispersed dot-shaped or finger-shaped electrodes, while the second N electrode 2142 and the second P electrode 2152 are surface electrodes. The first electrode 3.1 and the second electrode 3.2 function as connecting electrodes that link the LED chip and the pad structure, and can be completed at the chip factory or completed independently before packaging. These are typically columnar structures, thicker than the N electrode 214 and P electrode 215, with a thickness of 1 μm to 100 μm, preferably 30 μm to 70 μm. The material is a metallic material or a metallic alloy, such as Ti, Ni, Cu, Au, Pt, or a combination thereof, but is not limited to these. The insulating layer serves to insulate the P and N electrodes from each other, as well as to protect the LED chip structure. In some embodiments, reflectivity is further incorporated, for example, by using a DBR structure with grooves of different insulating materials, or by sandwiching a metallic reflective layer within the insulating material. The conductive layer 217 performs a current diffusion function, is laid flat on the surface of the P-type semiconductor layer 213 over the largest possible area, is translucent, and is an indium tin oxide (ITO) layer or an indium zinc oxide (IZO) layer.

[0028] In this embodiment, the first electrode 3.1 and the second electrode 3.2 are made of multilayer metal as a structure that connects the LED chip to the first pad 6.1 and the second pad 6.2. From the end closest to the LED chip toward the end closest to the pad structure, they sequentially include a Ti layer, a Cu layer, a Ni layer, and an Au layer, or sequentially a Cr layer, a Cu layer, a Ni layer, and an Au layer. Here, the Ti layer or Cr layer functions as an adhesive layer and has a thickness of 100 Å to 5000 Å. The Cu layer has extremely good conductivity and heat dissipation performance and is the main component of the first electrode 3.1 and the second electrode 3.2, with a thickness of 1 μm to 100 μm, preferably 30 μm to 60 μm. The Au layer is the outermost metal and has a thickness of 200 Å to 5000 Å, preferably 650 Å to 950 Å. The Ni layer is provided between the Cu layer and the Au layer and has a thickness of 1 μm to 10 μm, preferably 2 μm to 4 μm.

[0029] In this embodiment, the arrangement of the first pad 6.1 and the second pad 6.2 completely overlaps with the first electrode 3.1 and the second electrode 3.2, and extends toward the edge of the first reflective layer 4, but does not extend all the way to the edge of the first reflective layer 4. First pad 6.1 and Second pad The shape of 6.2 is rectangular, square, or circular in plan view, and the sum of the base areas is 0.3 to 1 times, preferably 0.6 to 0.95 times, the package dimensions Dw of the LED chip 2. The relatively large pad structure is for one reason of heat dissipation and for one reason of facilitating connection with external electrodes. In other embodiments (not shown), the first pad 6.1 and the second pad 6.2 may extend to the edge of the first reflective layer 4 or extend beyond the edge of the first reflective layer 4.

[0030] in particular, First pad 6.1 and Second pad6.2 includes an upper metal layer close to the LED chip 2 and a lower metal layer far from the LED chip. The upper metal layer is a Cu metal layer, and the lower metal layer is an Au metal layer, a Sn paste layer, or a SnAg alloy layer. The thickness of the upper metal layer is 1 μm to 100 μm, preferably 20 μm to 50 μm, and the thickness of the lower metal layer is 1 μm to 100 μm, preferably 20 μm to 50 μm. If the lower metal layer is a SnAg alloy layer, the Ag content is 0.5% to 3.5%.

[0031] In one embodiment, a Cr or Ti adhesive metal layer is further provided between the upper metal layer and the LED chip 2, and the thickness of the adhesive metal layer is 100 Å to 5000 Å. In another embodiment, a Ni or Pt barrier layer is further provided between the upper metal layer and the lower metal layer, and the thickness of the barrier layer is 1 μm to 10 μm, preferably 1.5 μm to 4 μm.

[0032] The fluorescent film layer 1 can be formed by first creating a precursor by mixing a dopant (additive) and a colloid, and then proceeding through a film deposition process. The dopant is a fluorescent powder and includes one or more of the following: KSF powder, nitride fluorescent powder, silicate fluorescent powder, chlorate fluorescent powder, YAG fluorescent powder, and sulfide-containing fluorescent powder. In this embodiment, the required LED package component emits white light, but the light emitted by the LED chip 2 is blue light, so yellow fluorescent powder is required to convert the blue light to white light.

[0033] In this embodiment, the reflectivity of the first reflective layer 4 and / or the second reflective layer 7 is 90% or more, and the material is a transparent silicone doped (added, mixed) with reflective particles, i.e., a reflective sealing layer. The reflective particles may be insulating particles such as TiO2, SiO2, or SiN, or metal particles such as Al particles, Ag particles, or Cu particles. Furthermore, First pad 6.1 and Second pad The spacing D2 between 6.2 is less than or equal to the spacing D1 between the first and second electrodes (D2 ≤ D1), and D2 ≥ 150 μm. If D2 is less than 150 μm, then D2 is too narrow. First pad 6.1 and Second pad When 6.2 is actually implemented and used, the diffusion and migration (shifting) of the Sn paste can easily cause the first pad 6.1 and the second pad 6.2 to connect, leading to a short circuit. First pad 6.1 and Second pad The shortest distance D3 > 0 between the sidewall of 6.2 and the sidewall of the second reflective layer 7 is preferably greater than 100 μm.

[0034] The upper end of the first reflective layer 4 is flush with the upper surface 2a of the LED chip 2, and the lower end is flush with the lower surface of the first electrode 3.1 and / or the second electrode 3.2. The upper end of the second reflective layer 7 is flush with the lower surface of the first electrode 3.1 and / or the second electrode 3.2, and the lower end is First pad 6.1 and / or Second pad 6.2 is flush with the lower surface. The width of the fluorescent film 1 is greater than the width of the LED chip 2 and covers the upper surface 2a of the LED chip and the top surface of the first reflective layer 4. Furthermore, in the LED package structure provided by the present invention, a cup structure 5 is provided between the first reflective layer 4 and the LED chip 2, and the cup structure 5 is provided on the peripheral side wall of the LED chip 2. The cup structure is a transparent reflective cavity, preferably made of transparent silicone.

[0035] Example 2 As shown in Figure 4, the differences between this embodiment and Embodiment 1 are as follows. In this embodiment, the fluorescent film 1 is first provided on the upper surface of the LED chip. Due to the presence of dicing lines, its width is greater than the width of the LED chip 2, and because the chip package structure of this embodiment includes a cup structure, the width of the fluorescent film 1 is approximately 50 to 200 μm greater than the width dimension of the LED chip 2. Subsequently, the cup structure 5 and the first reflective layer 4 are provided. The cup structure is provided around the upper end of the side surface of the LED chip 2. The first reflective layer 4 covers the side walls of the LED chip 2 and the fluorescent film 1, and the top surface of the first reflective layer 4 is flush with the top surface 1 of the fluorescent film. Other parts have the same structure, so their explanation is omitted here. Compared to the structure of Embodiment 1, the structure of this embodiment is similar in that it emits light from one side, but its emission angle is smaller (110° to 120°), and the color temperature distribution of light in space is more concentrated.

[0036] Example 3 As shown in Figure 5, the differences between this embodiment and Embodiment 1 are as follows. In this embodiment, the width of the fluorescent film 1 is greater than the width of the LED chip 2, and the fluorescent film 1 covers the upper surface of the LED chip while simultaneously enclosing a portion of the side surface 2c of the LED chip. The top surface of the first reflective layer 4 is coplanar with the bottom surface of the fluorescent film, and the side walls are coplanar with the side walls of the fluorescent film. Other parts have the same structure, so their explanation is omitted here. Compared to the structure of Embodiment 1, the structure in this embodiment is a five-sided light-emitting structure, has a larger light-emitting angle that can reach 150°, and utilizes the side light of the LED, resulting in higher emitted brightness.

[0037] Example 4 As shown in Figure 6, the differences between this embodiment and Embodiment 1 are as follows: First pad The first through trench 6.11 is opened within 6.1. Second padA second through groove 6.21 is provided within 6.2. The functions of the first through groove 6.11 and the second through groove 6.21 are as follows: The area difference between the first pad 6.1 and the second pad 6.2 and the first electrode 3.1 and the second electrode 3.2 increases the stress between them and the reflective sealing layer, which is the first reflective layer 4. However, by designing through grooves on the first pad 6.1 and the second pad 6.2, the stress can be effectively relieved and the risk of delamination of the metal layer can be reduced. However, the first through groove 6.11 does not communicate with the first electrode 3.1, and the second through groove 6.21 does not communicate with the second electrode 3.2, in order to avoid leakage current. Therefore, as shown in this embodiment, the first through groove 6.11 and the second through groove 6.21 need to be provided on the edge side, far from the first electrode 3.1 and the second electrode 3.2. Alternatively, the depth of the first through groove 6.1 and the second through groove can be made smaller than the thickness of the first pad and the second pad. The shapes of the first through groove 6.11 and the second through groove 6.21 can be square, circular, arc-shaped, triangular, polygonal, or a combination of one or more of these shapes, and in this embodiment, a square shape is selected. There can be multiple first through grooves 6.11 and second through grooves 6.21, which are distributed within the first pad 6.1 and second pad 6.2, respectively, occupying 0% to 15% of the area of ​​the first pad 6.1 and the second pad 6.2, and preferably 2% to 10%.

[0038] In this embodiment, the first through groove 6.1 and the second through groove 6.2 need to be provided on the edge side furthest from the first electrode 3.1 and the second electrode 3.2, and their patterns are different. The first through groove 6.1 is a U-shaped through groove consisting of multiple square structures, and the second through groove 6.2 is an arc-shaped through groove, which is used to distinguish the polarity of the first pad 6.1 and the second pad 6.2. Similarly, because the shapes of the first through groove 6.1 and the second through groove 6.2 are different, it is relatively difficult to make their areas the same, but when the areas of the first pad 6.1 and the second pad 6.2 are the same, the area difference between the first through groove 6.1 and the second through groove 6.2 is 10% or less.

[0039] Example 5 As shown in Figure 7, the difference between this embodiment and Embodiment 4 is that in this embodiment... First pad 6.1 and Second pad 6.2 consists of two interlocking semicircular discs, with the two electrodes 3 located on the side closest to the straight edge of each semicircular disc. The rest of the structure is the same, so we will omit the explanation here.

[0040] The above-described implementation is merely for the purpose of illustrating the technical idea and features of the present invention, and its purpose is to enable those skilled in the art to understand and implement the present invention; it does not limit the scope of protection of the present invention. All equivalent transformations or modifications made based on the spiritual substance of the present invention should be included within the scope of protection of the present invention.

Claims

1. An LED package structure comprising an LED chip (2), a fluorescent film (1) covering the upper surface of the LED chip (2), a pad structure (6) provided on the lower surface of the LED chip (2), a first reflective layer (4) covering the side wall of the LED chip (2), and a second reflective layer (7) covering the side wall of the pad structure, The LED package structure is characterized in that the pad structure (6) includes a first pad (6.1) electrically connected to the first electrode (3.1) of the LED chip (2) and a second pad (6.2) connected to the second electrode (3.2) of the LED chip, the first pad (6.1) and the second pad (6.2) are insulated from each other, and the sum of the bottom areas of the pad structure (6) is 0.3 to 1 times the bottom area of ​​the package structure of the LED chip (2).

2. The LED package structure according to claim 1, characterized in that the first electrode (3.1) and / or second electrode (3.2) of the LED chip (2) are made of multilayer metal, and are, in order from the end closest to the LED chip (2) toward the end closest to the pad structure (6), Ti layer, Cu layer, Ni layer, Au layer, or in order Cr layer, Cu layer, Ni layer, Au layer.

3. The LED package structure according to claim 2, characterized in that the thickness of the first electrode (3.1) and / or the second electrode (3.2) is 1 μm to 100 μm, the thickness of the Ti layer or Cr layer is 100 Å to 5000 Å, the thickness of the Cu layer is 1 μm to 100 μm, the thickness of the Ni layer is 1 μm to 10 μm, and the thickness of the Au layer is 200 Å to 5000 Å.

4. The LED package structure according to claim 1, characterized in that the first pad structure (6.1) and the second pad structure (6.2) include an upper metal layer close to the LED chip (2) and a lower metal layer far from the LED chip (2), wherein the upper metal layer is a Cu metal layer and the lower metal layer is an Au metal layer, a Sn metal layer, or a SnAg alloy layer.

5. The thickness of the upper metal layer is 1 μm to 100 μm, the thickness of the lower metal layer is 1 μm to 100 μm, and / or A Cr or Ti adhesive metal layer is further provided between the upper metal layer and the LED chip (2), the thickness of the adhesive metal layer being 100 Å to 5000 Å, and / or A Ni or Pt barrier layer is further provided between the upper metal layer and the lower metal layer, the thickness of the barrier layer being 1 μm to 10 μm, and / or The LED package structure according to claim 4, characterized in that the lower metal layer is a SnAg alloy layer with an Ag content of 0.5% to 3.5%.

6. A first through groove (6.11) is provided within the first pad (6.1) that does not communicate with the first electrode (3.1), and / or, The LED package structure according to claim 1, characterized in that a second through groove (6.21) is provided in the second pad (6.2) and does not communicate with the second electrode (3.2).

7. The patterns and / or sizes of the first through groove (6.11) and the second through groove (6.21) are different. The area of ​​the first through groove (6.11) occupies 0% to 15% of the first pad (6.1), and / or The LED package structure according to claim 6, characterized in that the area of ​​the second through groove (6.21) occupies 0% to 15% of the second pad (6.2).

8. The LED package structure according to claim 1, characterized in that the distance D2 between the first pad (6.1) and the second pad (6.2) is less than or equal to the distance D1 between the first electrode (3.1) and the second electrode (3.2), and D2 ≥ 150 μm.

9. The LED package structure according to claim 1, characterized in that the upper end of the first reflective layer (4) is higher than the lower surface of the LED chip (2) and the lower end is flush with the lower surface of the LED chip (2), the upper end of the second reflective layer (7) is flush with the lower surface of the LED chip (2) and the lower end is flush with the lower surface of the pad structure (6).

10. The width of the fluorescent film (1) is greater than the width of the LED chip (2), and the width of the fluorescent film (1) is less than the width of the first reflective layer (4), and the top surface of the first reflective layer and the top surface of the fluorescent film (1) are flush, or The width of the fluorescent film (1) is greater than the width of the LED chip (2), the top surface of the first reflective layer (4) and the upper surface of the LED chip (2) are flush, and the fluorescent film (1) covers the upper surface of the LED chip (2) and the top surface of the first reflective layer (4), or, The LED package structure according to claim 9, characterized in that the width of the fluorescent film (1) is greater than the width of the LED chip (2), the fluorescent film (1) covers the upper surface of the LED chip (2) and encloses a part of the side surface of the LED chip (2), and the top surface of the first reflective layer (4) and the bottom of the side surface of the fluorescent film (1) are flush.

11. The LED package structure according to claim 9, characterized in that the width of the fluorescent film (1) is greater than the width of the LED chip (2), the fluorescent film (1) covers the upper surface of the LED chip (2) and encloses a part of the side surface of the LED chip (2), and the top surface of the first reflective layer (4) and the bottom of the side surface of the fluorescent film (1) are flush.

12. The LED package structure according to claim 1, characterized in that a cup structure (5) is provided between the first reflective layer (4) and the LED chip (2), and the cup structure (5) is provided on the peripheral side wall of the LED chip (2).

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