Light emitting device

Abstract

The application provides a light emitting device, which comprises a substrate, a bonding pad, a solder pad and a light emitting unit. The bonding pad is arranged on the substrate. The solder pad is arranged on the bonding pad. The light emitting unit is electrically connected with the bonding pad through the solder pad. The solder pad comprises a plurality of separated conductive elements.

Description

Technical Field

[0001] This application relates to a light-emitting device, and more particularly to the structural design of the bonding pad of the light-emitting device. Background Technology

[0002] Electronic products, including display panels, such as tablets, laptops, smartphones, monitors, and televisions, have become indispensable necessities in modern society. With the booming development of these portable electronic products, consumers have high expectations for their quality, functionality, and price.

[0003] In electronic products (e.g., display panels), light-emitting devices are typically bonded or electrically connected to the substrate via contact pads, bonding pads, or other conductive elements. However, due to the difference in the coefficient of thermal expansion (CTE) between the substrate and the light-emitting device, the joint between the substrate and the light-emitting device is easily affected by stress when the temperature changes, resulting in cracks or peeling.

[0004] As mentioned above, existing electronic products with light-emitting devices still do not meet the requirements in all aspects. Therefore, structural design to further improve the reliability of light-emitting devices remains one of the topics that the industry is currently focusing on researching. Summary of the Invention

[0005] According to some embodiments of this application, a light-emitting device is provided, comprising a substrate, bonding pads, solder pads, and a light-emitting unit. The bonding pads are disposed on the substrate, the solder pads are disposed on the bonding pads, the light-emitting unit is electrically connected to the bonding pads through the solder pads, and the solder pads comprise a plurality of separate conductive elements. Attached Figure Description

[0006] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein:

[0007] Figure 1A This diagram shows a cross-sectional structural schematic of the light-emitting device according to some embodiments of this application;

[0008] Figure 1B This shows a top view schematic diagram of the light-emitting device according to some embodiments of this application;

[0009] Figure 2 This diagram shows a top view of some components of the light-emitting device according to some embodiments of this application;

[0010] Figure 3 This diagram shows a top view of some components of the light-emitting device according to some embodiments of this application;

[0011] Figure 4 This diagram shows a top view of some components of the light-emitting device according to some embodiments of this application;

[0012] Figure 5 This diagram shows a top view of some components of the light-emitting device according to some embodiments of this application;

[0013] Figure 6 This diagram shows a top view of some components of the light-emitting device according to some embodiments of this application;

[0014] Figure 7A This diagram shows a cross-sectional structural schematic of the light-emitting device according to some embodiments of this application;

[0015] Figure 7B The diagram shows a top view of the structure of the light-emitting device according to some embodiments of this application.

[0016] Explanation of component labels in the diagram:

[0017] 10, 20: Light-emitting devices

[0018] 100: Substrate

[0019] 102: First insulating layer

[0020] 104: Second insulating layer

[0021] 200: Joint pad

[0022] 200E, 200Ea, 200Eb, 200Ec: Conductive elements

[0023] 202: Third Insulation Layer

[0024] 202e: Edge

[0025] 202p: Opening

[0026] 302: Solder pad

[0027] 304: Welding material

[0028] 400: Light-emitting unit

[0029] 402: Conductor frame

[0030] 402t: Top surface

[0031] 403: Luminous area

[0032] 404a: First electrode layer

[0033] 404b: Second electrode layer

[0034] 500: Protective Material

[0035] 500t: Top surface

[0036] CT: Center

[0037] L: Length

[0038] OP: Pores

[0039] T: Thickness

[0040] W: Width Detailed Implementation

[0041] The following provides a detailed description of the light-emitting device according to embodiments of this application. It should be understood that the following description provides many different embodiments for implementing various forms of some embodiments of this application. The specific elements and arrangements described below are merely for simple and clear description of some embodiments of this application. Of course, these are only examples and not limitations of this application. Furthermore, similar and / or corresponding reference numerals may be used in different embodiments to identify similar and / or corresponding elements for clear description of this application. However, the use of these similar and / or corresponding reference numerals is only for simple and clear description of some embodiments of this application and does not represent any association between the different embodiments and / or structures discussed.

[0042] This application can be understood by referring to the following detailed description and the accompanying drawings. It should be noted that, for ease of understanding and to keep the drawings concise, many of the drawings in this application only depict a portion of the electronic device, and certain components in the drawings are not drawn to scale. Furthermore, the number and size of each component in the drawings are for illustrative purposes only and are not intended to limit the scope of this application.

[0043] It should be understood that the elements or devices in the accompanying drawings can exist in various forms well known to those skilled in the art. Furthermore, relative terms such as "lower," "bottom," "higher," or "top" may be used in the embodiments to describe the relative relationship of one element to another in the drawings. It is understood that if the devices in the drawings are flipped upside down, the element described as being on the "lower" side will become the element on the "higher" side. The embodiments of this application can be understood in conjunction with the accompanying drawings, which are also considered part of the application description. Furthermore, when a first material layer is mentioned as being located on or above a second material layer, this includes situations where the first material layer and the second material layer are in direct contact, or situations where one or more other material layers may be spaced apart, in which case the first material layer and the second material layer may not be in direct contact.

[0044] Throughout this application, certain terms are used to refer to specific elements. Those skilled in the art will understand that electronic device manufacturers may use different names to refer to the same element. This document is not intended to distinguish between elements that have the same function but different names. In the following description and claims, words such as “comprising,” “containing,” and “having” are open-ended terms and should therefore be interpreted as “containing but not limited to…”. Therefore, when the terms “comprising,” “containing,” and / or “having” are used in the description of this application, they specify the presence of the corresponding feature, area, step, operation, and / or component, but do not exclude the presence of one or more of the corresponding feature, area, step, operation, and / or component.

[0045] The directional terms used herein, such as "up," "down," "front," "back," "left," and "right," are for reference only when referring to the accompanying drawings. Therefore, the directional terms used are for illustrative purposes and not for limiting this application. In the accompanying drawings, each figure illustrates the general features of the methods, structures, and / or materials used in a particular embodiment. However, these figures should not be construed as defining or limiting the scope or nature covered by these embodiments. For example, for clarity, the relative dimensions, thicknesses, and positions of various films, regions, and / or structures may be reduced or enlarged.

[0046] When a component (e.g., a membrane or region) is referred to as "on another component," it can be directly on that component, or there may be other components between them. Conversely, when a component is referred to as "directly on another component," there are no components between them. Furthermore, when a component is referred to as "on another component," the two components have a vertical relationship in the planar view, and this component can be above or below the other component, depending on the orientation of the device.

[0047] Furthermore, it should be understood that although terms such as “first,” “second,” “third,” etc., may be used herein to describe various elements, components, or parts, these elements, components, or parts should not be limited by these terms. These terms are only used to distinguish different elements, components, regions, layers, or parts. Therefore, a first element, component, region, layer, or part discussed below may be referred to as a second element, component, region, layer, or part without departing from the teachings of this application.

[0048] In this text, the terms "approximately" and "substantially" typically indicate that a given value or range is within 10%, 5%, 3%, 2%, 1%, or 0.5%. The given quantities are approximate; that is, even without specific mention of "approximately" or "substantially," their meaning is implied. Furthermore, the phrase "the range is between the first and second values" indicates that the range includes the first value, the second value, and other values ​​in between.

[0049] It should be understood that the following embodiments can be implemented by substituting, recombining, or mixing features from several different embodiments to complete other embodiments without departing from the spirit of this application. Features between embodiments can be arbitrarily mixed and matched as long as they do not violate the spirit of the invention or conflict with it.

[0050] Furthermore, in the embodiments of this application, the thickness, length, and width can be measured using an optical microscope, while the thickness can be measured from a cross-sectional image in an electron microscope, but this is not a limitation. Additionally, any two values ​​or directions used for comparison may have a certain degree of error. If the first value equals the second value, it implies an error of approximately 10% between the first and second values; if the first direction is perpendicular to the second direction, the angle between the first and second directions may be between 80 and 100 degrees; if the first direction is parallel to the second direction, the angle between the first and second directions may be between 0 and 10 degrees.

[0051] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by those skilled in the art. It is understood that such terms, for example, as defined in commonly used dictionaries, should be interpreted as having a meaning consistent with the relevant art and the background or context of this application, and should not be interpreted in an idealized or overly formal manner, unless specifically defined in the embodiments of this application.

[0052] According to some embodiments of this application, a light-emitting device is provided, including a light-emitting unit, bonding pads and solder pads connecting the light-emitting unit and a substrate. The solder pads have multiple separate conductive elements. The multiple separate conductive elements can disperse the stress at the contact position between the solder pad and the substrate, reduce the situation where the stress is excessively concentrated at the edge of the solder pad, and thereby reduce the risk of substrate cracking or the light-emitting unit peeling off from the substrate.

[0053] Please refer to Figure 1A as well as Figure 1B , Figure 1A This diagram shows a cross-sectional view of the light-emitting device 10 according to some embodiments of this application. Figure 1B The diagram shown is a top view of the structure of the light-emitting device 10 according to some embodiments of this application. It should be understood that, for clarity, Figure 1A as well as Figure 1B Some components of the light-emitting device 10 are omitted in the illustration; only some components are shown schematically. According to some embodiments, additional features may be added to the light-emitting device 10 described below. According to other embodiments, some features of the light-emitting device 10 described below may be replaced or omitted.

[0054] According to some embodiments, the light-emitting device 10 may include a substrate 100, a bonding pad 200, a light-emitting unit 400, and a solder pad 302. The bonding pad 200 may be disposed on the substrate 100 and located between the substrate 100 and the light-emitting unit 400. The solder pad 302 is disposed on the bonding pad 200, and the light-emitting unit 400 may be electrically connected to the bonding pad 200 through the solder pad 302.

[0055] According to some embodiments, substrate 100 may serve as a driving substrate, and substrate 100 may have a driving circuit (not shown). The driving circuit may include active driving circuitry and / or passive driving circuitry. According to some embodiments, the driving circuit may include thin-film transistors (TFTs) (e.g., switching transistors, driving transistors, reset transistors, or other thin-film transistors), data lines, scan lines, conductive pads, dielectric layers, or other lines, but is not limited thereto. For example, a switching transistor may be used to control the switching of the light-emitting unit 400. Furthermore, the thin-film transistor may be a top-gate thin-film transistor, a bottom-gate thin-film transistor, or a dual-gate or double-gate thin-film transistor. According to some embodiments, the thin-film transistor includes at least one semiconductor layer, which includes, but is not limited to, amorphous silicon, metal oxide, other suitable materials, or combinations thereof, but is not limited thereto. Amorphous silicon, for example, is low-temp polysilicon (LTPS). The metal oxide may include, but is not limited to, indium gallium zinc oxide (IGZO), indium zinc oxide (IZO), indium gallium zinc tin oxide (IGZTO), other suitable materials, or combinations thereof. According to some embodiments, different thin-film transistors may have the aforementioned different semiconductor materials. According to some embodiments, the driving circuit may control the light-emitting unit 400 via an external integrated circuit (IC) or microchip, but is not limited to this.

[0056] According to some embodiments, substrate 100 may comprise a rigid substrate or a flexible substrate. According to some embodiments, the material of substrate 100 may comprise, but is not limited to, glass, semiconductor materials, quartz, sapphire, polyimide (PI), polycarbonate (PC), polyethylene terephthalate (PET), other suitable materials, or combinations thereof. According to some embodiments, the semiconductor material may comprise, but is not limited to, silicon (Si), germanium (Ge), other suitable semiconductor materials, or combinations thereof. According to some embodiments, the material of substrate 100 may comprise, but is not limited to, low-temp polysilicon (LTPS), metal oxides, other suitable materials, or combinations thereof.

[0057] like Figure 1A as well as Figure 1B As shown, in the normal direction of the substrate 100 (e.g., the Z direction in the figure), the bonding pad 200 overlaps with the light-emitting unit 100. According to some embodiments, the bonding pad 200 can be electrically connected to the driving circuit (not shown) on the aforementioned substrate 100, and the bonding pad 200 and the light-emitting unit 400 are electrically connected through the solder pad 302 to transmit the signal of the driving circuit to the light-emitting unit 400.

[0058] According to some embodiments, the material of the bonding pad 200 includes a conductive material, such as a metallic material, but is not limited thereto. For example, the metallic material may include copper (Cu), aluminum (Al), indium (In), ruthenium (Ru), tin (Sn), gold (Au), platinum (Pt), zinc (Zn), silver (Ag), titanium (Ti), lead (Pb), nickel (Ni), chromium (Cr), magnesium (Mg), palladium (Pd), copper alloys, aluminum alloys, indium alloys, ruthenium alloys, tin alloys, gold alloys, platinum alloys, zinc alloys, silver alloys, titanium alloys, lead alloys, nickel alloys, chromium alloys, magnesium alloys, palladium alloys, other suitable conductive materials, or combinations thereof, but is not limited thereto.

[0059] Furthermore, according to some embodiments, the light-emitting unit 400 may include a light-emitting diode (LED), which may include, for example, an organic light-emitting diode (OLED), an inorganic light-emitting diode, a mini LED, a micro LED, or a quantum dot LED (e.g., QLED or QDLED), other suitable light-emitting diodes, or any combination thereof, but is not limited thereto.

[0060] Specifically, according to some embodiments, the light-emitting unit 400 may include a light-emitting region 403 (e.g., Figure 1B As shown, there are a first electrode layer 404a and a second electrode layer 404b. According to some embodiments, a light-emitting region 403 may be disposed in a leadframe 402, which is electrically connected to the first electrode layer 404a and the second electrode layer 404b. According to some embodiments, in a top-viewing angle, a portion of the first electrode layer 404a and a portion of the second electrode layer 404b protrude beyond the outer edge of the leadframe 402.

[0061] According to some embodiments, the light-emitting region 403 may include, for example, a first semiconductor layer (not shown), a second semiconductor layer (not shown), and a quantum well layer (not shown) disposed between the first semiconductor layer and the second semiconductor layer, but this application is not limited thereto. Furthermore, the first and second semiconductor layers may be formed of group III-V compounds with p-type and n-type conductivity types (e.g., gallium nitride with p-type and n-type conductivity types). In addition, the quantum well layer may include a single quantum well (SQW) or a multiple quantum well (MQW). According to some embodiments, group III-V compounds may include gallium nitride (GaN), indium nitride (InN), aluminum nitride (AlN), indium gallium nitride (InGaN), aluminum gallium nitride (AlGaN), aluminum gallium indium nitride (AlGaInN), other suitable materials, or combinations thereof, but are not limited thereto. According to some embodiments, the quantum well layer may include indium gallium nitride, gallium nitride, other suitable materials, or combinations thereof, but are not limited thereto.

[0062] According to some embodiments, the first electrode layer 404a and the second electrode layer 404b may be the anode electrode and cathode electrode of the light-emitting unit 400. According to some embodiments, the bonding pad 200 may be electrically connected to the first electrode layer 404a and the second electrode layer 404b of the light-emitting unit 400. Furthermore, as... Figure 1A as well as Figure 1B As shown, according to some embodiments, the first electrode layer 404a and the second electrode layer 404b have different sizes. For example, the size of the second electrode layer 404b can be larger than the size of the first electrode layer 404a, thereby improving the heat dissipation effect of the light-emitting unit 400.

[0063] Furthermore, according to some embodiments, the light-emitting device 10 may further include a first insulating layer 102, a second insulating layer 104, and a third insulating layer 202, wherein the second insulating layer 104 is disposed on the first insulating layer 102, and the bonding pad 200 and the third insulating layer 202 are disposed on the second insulating layer 104. According to some embodiments, a portion of the first insulating layer 102 and a portion of the second insulating layer 104 are disposed between the substrate 100 and the bonding pad 200, a portion of the third insulating layer 202 covers the bonding pad 200, and a portion of the third insulating layer 202 is in direct contact with the second insulating layer 104.

[0064] According to some embodiments, the materials of the first insulating layer 102, the second insulating layer 104, and the third insulating layer 202 may include insulating materials, such as silicon oxide, silicon nitride, silicon oxynitride, other suitable insulating materials, or combinations thereof, but are not limited thereto.

[0065] Furthermore, according to some embodiments, the light-emitting device 10 may further include a welding material 304, which may be disposed between the light-emitting element 400 and the bonding pad 200. Specifically, the welding material 304 may be disposed between the electrode layer (e.g., the first electrode layer 404a and the second electrode layer 404b) and the bonding pad 302. The welding material 304 can be used to bond the light-emitting element 400 and the bonding pad 200. More specifically, the welding material 304 can be used to bond the electrode layer (e.g., the first electrode layer 404a or the second electrode layer 404b) and the bonding pad 302. According to some embodiments, the welding material 304 may simultaneously contact the electrode layer (e.g., the first electrode layer 404a or the second electrode layer 404b) and the intermediate layer 302 of the light-emitting unit 400. Figure 1B As shown, according to some embodiments, in a top view, a portion of the welding material 304 protrudes from the outer edges of the first electrode layer 404a and the second electrode layer 404b.

[0066] According to some embodiments, the material of solder pad 302 may include nickel (Ni), nickel alloys, copper alloys, other suitable materials, or combinations thereof, but is not limited thereto. According to some embodiments, solder material 304 may include tin (Sn), aluminum (Al) tin alloys, aluminum alloys, other suitable solder materials, or combinations thereof, but is not limited thereto.

[0067] According to some embodiments of this application, the solder pad 302 may include a plurality of separate conductive elements 200E (e.g., such as...). Figures 2 to 6 As shown). In detail, as Figure 1A as well as Figure 1B As shown, the third insulating layer 202 disposed on the bonding pad 200 can be patterned to have a plurality of openings 202p. In a top view, the shapes of the plurality of separate conductive elements 200E are defined by the plurality of openings 202p of the third insulating layer 202. Furthermore, according to some embodiments, solder pads 302 are disposed in the plurality of openings 202p of the third insulating layer 202. According to some embodiments, the third insulating layer 202 can serve as a pixel definition layer (PDL) of the light-emitting device 10.

[0068] Furthermore, according to some embodiments, a portion of the third insulating layer 202 may extend between the bonding pad 200 and the solder pad 302. More specifically, according to some embodiments, the solder pad 302 has multiple separated portions, each of which may contact the bonding pad 200 exposed by a plurality of openings 202p. According to some embodiments, in the normal direction of the substrate 100 (e.g., the Z direction in the figure), the multiple separated portions of the solder pad 302 may partially overlap with the third insulating layer 202. According to some embodiments, the solder material 304 may have pores OP, which may be located between the multiple separated portions of the solder pad 302 and on the third insulating layer 202.

[0069] Furthermore, according to some embodiments, in a top-view perspective, the edge 202e of the third insulating layer 202, which is farther from the center CT of the light-emitting unit 400, protrudes beyond the outer edges of the lead frame 402, the first electrode layer 404a, and the second electrode layer 404b. In the normal direction of the substrate 100 (e.g., the Z direction in the figure), the edge 202e does not overlap with the light-emitting unit 400. According to some embodiments, the center CT of the light-emitting unit 400 can be the geometric center of the top surface of the light-emitting area 403. For example, the center CT of the light-emitting area 403, which has a similar rectangular or square shape, can be the intersection of two diagonals. In some embodiments, if the light-emitting area 403 is circular or elliptical, the center CT of the light-emitting area 403 can be the center of a circle; if the light-emitting area 403 is irregularly shaped and the center CT cannot be defined using the above method, then a minimum circle that can surround the light-emitting area 403 is drawn, and the center of this minimum circle is defined as the center CT of the light-emitting area 403. However, this application is not limited to this.

[0070] It is worth noting that, according to some embodiments of this application, the patterned third insulating layer 202 can define the range of a plurality of separate conductive elements 200E disposed on the bonding pad 200, which can disperse the stress concentrated at the edge of the bonding pad 200 and reduce the risk of substrate 100 cracking or light-emitting unit 400 peeling off from substrate 100.

[0071] Next, please refer to Figure 2 , Figure 2 The diagram shows a top view of some elements of the light-emitting device 10 according to some embodiments of this application. Specifically, Figure 2 Only a top view of the bonding pads 200 and solder pads 302 in the light-emitting device 10 is shown to clearly illustrate the arrangement and shape of the conductive elements 200E in the solder pads 302. Furthermore, it should be understood that components or elements that are the same or similar to those described above will be indicated by the same or similar designations, and their materials, manufacturing methods, and functions will be the same or similar as described above; therefore, this part will not be repeated in the following text.

[0072] As for the foregoing, according to some embodiments, the third insulating layer 202 may be patterned to have a plurality of openings 202p, which can define the shape, size, and arrangement of the conductive elements 200E disposed on the bonding pad 200. For example... Figure 2 As shown, according to some embodiments, at least a portion of the plurality of openings 202p may be rectangular. According to some embodiments, the rectangular openings 202p may have rounded corners RC. According to some embodiments, the radius of curvature of the rounded corners RC may be between 3 micrometers (μm) and 100 micrometers (μm) (i.e., 3 μm ≤ radius of curvature ≤ 100 μm).

[0073] In addition, such as Figure 2 As shown, conductive elements 200E can be arranged adjacently along the X and Y directions in the figure. According to some embodiments, the angle between the X and Y directions is approximately 90 degrees.

[0074] Furthermore, in the normal direction of the substrate 100 (e.g., the Z direction in the figure), the pads 302 overlapping the first electrode layer 404a and the second electrode layer 404b may each have a length L and a width W. According to some embodiments, the length L of the pads 302 may range from 0.03 mm to 3 mm (i.e., 0.03 mm ≤ length L ≤ 3 mm), or from 0.5 mm to 2.5 mm, or from 1 mm to 1.5 mm. According to some embodiments, the width W of the pads 302 may range from 0.03 mm to 3 mm (i.e., 0.03 mm ≤ width W ≤ 3 mm), or from 0.5 mm to 2.5 mm, or from 1 mm to 1.5 mm.

[0075] According to an embodiment of this application, the length L of the aforementioned solder pad 302 refers to the length of the solder pad 302 on a plane perpendicular to the normal direction of the substrate 100 (e.g., the XY plane in the figure). Furthermore, according to an embodiment of this application, the width W of the aforementioned solder pad 302 refers to the width of the solder pad 302 on a plane perpendicular to the normal direction of the substrate 100 (e.g., the XY plane in the figure).

[0076] Furthermore, according to embodiments of this application, the length, width, or thickness of each element, or the distance between elements, can be measured using an optical microscopy (OM), a scanning electron microscope (SEM), an alpha-step thickness gauge, an elliptic gauge, or other suitable methods. Specifically, according to some embodiments, a scanning electron microscope can be used to obtain cross-sectional images of the structure and measure the length, width, or thickness of each element, or the distance between elements.

[0077] Next, please refer to Figure 3 , Figure 3 This diagram shows a top view of the conductive elements 200E of the bonding pads 200 and solder pads 302 of the light-emitting device 10 according to other embodiments of this application. Figure 3 As shown, according to some embodiments, at least a portion of the plurality of openings 202p may be circular, that is, the conductive element 200E of the solder pad 302 may have a circular shape, but this application is not limited thereto. According to different embodiments, the conductive element 200E (the openings 202p of the third insulating layer 202) may have any other suitable shape according to product requirements, such as elliptical, triangular, pentagonal, hexagonal, or irregular shape, etc., and is not limited thereto.

[0078] Next, please refer to Figure 4 , Figure 4 This diagram shows a top view of the conductive elements 200E of the bonding pads 200 and solder pads 302 of the light-emitting device 10 according to other embodiments of this application. Figure 4 As shown, according to some embodiments, at least two of the plurality of openings 202p in the third insulating layer 202 have different sizes, for example, two, three, four, or five, but are not limited thereto. It should be understood that, according to different embodiments, the third insulating layer 202 may have openings 202p of various sizes depending on product requirements, and this application is not limited thereto. In some embodiments, the different sizes of the two elements may be due to different lengths, different widths, or different areas, but are not limited thereto.

[0079] Specifically, according to some embodiments, the center CT (e.g., at a distance of 400 from the light-emitting unit) Figure 1BAs shown, the size of the closer opening 202p is larger than the size of the other opening farther from the center CT of the light-emitting unit 400. That is, the size of the conductive element 200E (denoted as 200Ea for clarity) closer to the center CT of the light-emitting unit 400 is larger than the size of the conductive element 200E (denoted as 200Eb for clarity) farther from the center CT of the light-emitting unit 400. Furthermore, according to some embodiments, the size of the conductive element 200E (denoted as 200Ec for clarity) farthest from the center CT of the light-emitting unit 400 is smaller than the sizes of conductive elements 200Eb and 200Ea.

[0080] It is worth noting that since stress tends to concentrate at the outer edge of the bonding pad 200 (i.e., away from the center CT of the light-emitting unit 400), placing smaller or more numerous conductive elements 200E at a location farther from the center CT of the light-emitting unit 400 can effectively disperse the stress concentrated at the edge of the bonding pad 200, reducing the risk of substrate 100 cracking or light-emitting unit 400 peeling off from substrate 100. Furthermore, retaining relatively larger conductive elements 200E at a location closer to the center CT of the light-emitting unit 400 can increase the contact area of ​​the bonding pad 302, improving the bonding strength between the two, and may also improve the current flow density between the light-emitting unit 400 and substrate 100, thus improving the quality of electrical connection.

[0081] Next, please refer to Figure 5 as well as Figure 6 , Figure 5 as well as Figure 6 This diagram shows a top view of the conductive elements 200E of the bonding pads 200 and solder pads 302 of the light-emitting device 10 according to other embodiments of this application. Figure 5 as well as Figure 6 As shown, according to some embodiments, the light-emitting device 10 may have four bonding pads 200. It should be understood that the number of bonding pads 200 connected to the light-emitting unit 400 may be adjusted accordingly depending on the form of the light-emitting unit 400 (e.g., different packaging forms). As described above... Figures 2 to 4 As shown in the embodiments, the light-emitting device 10 may have two bonding pads 200, but this application is not limited thereto. Furthermore, in these embodiments, the conductive elements 200E of the bonding pads 302 may also have different sizes (e.g., Figure 5 (as shown), or have the same size (such as) Figure 6 (As shown).

[0082] Next, please refer to Figure 7A as well as Figure 7B , Figure 7A This diagram shows a cross-sectional view of the light-emitting device 20 according to some embodiments of this application. Figure 7BThe diagram shown is a top view of the light-emitting device 20 according to some embodiments of this application. It should be understood that, for clarity, Figure 7A as well as Figure 7B Some components of the light-emitting device 20 are omitted from the diagram; only some components are schematically shown. According to some embodiments, additional features may be added to the light-emitting device 20 described below. According to other embodiments, some features of the light-emitting device 20 described below may be replaced or omitted.

[0083] like Figure 7A As shown, according to some embodiments, the light-emitting device 20 may further include a protective material 500, which may be disposed on the substrate 100 and cover the light-emitting unit 400 and the bonding pad 200. More specifically, according to some embodiments, the protective material 500 may cover the surfaces of the light-emitting unit 400, the soldering material 304, and the third insulating layer 202. The protective material 500 can reduce the impact of moisture or oxygen in the environment on the light-emitting device 20, reducing the risk of corrosion or oxidation of the components.

[0084] like Figure 7A As shown, according to some embodiments, the top surface 500t of the protective material 500 may be substantially flush with the top surface 402t of the lead frame 402 of the light-emitting unit 400. However, according to other embodiments, the top surface 500t of the protective material 500 may be lower or higher than the top surface 402t of the lead frame 402. Furthermore, the protective material 500 may have a thickness T, which, according to some embodiments, may be between 50 micrometers (μm) and 150 micrometers (μm) (i.e., 50 μm ≤ thickness T ≤ 150 μm), or between 100 micrometers (μm) and 150 micrometers (μm) (i.e., 100 μm ≤ thickness T ≤ 150 μm), but is not limited thereto.

[0085] According to the embodiments of this application, the thickness T of the aforementioned protective material 500 refers to the maximum thickness of the protective material 500 in the direction normal to the substrate 100 (e.g., the Z direction in the figure).

[0086] According to some embodiments, the protective material 500 may comprise organic materials, inorganic materials, other suitable protective materials, or combinations thereof, but is not limited thereto. According to some embodiments, the inorganic material may comprise silicon nitride, silicon oxide, silicon oxynitride, aluminum oxide, or other suitable materials, but is not limited thereto. According to some embodiments, the organic material may comprise epoxy resins, silicone resins, acrylic resins (e.g., polymethyl methacrylate (PMMA), benzocyclobutene (BCB), polyimide, polyester, polydimethylsiloxane (PDMS), polyfluoroalkoxy (PFA)), other suitable materials, or combinations thereof, but is not limited thereto.

[0087] Furthermore, compared to light-emitting devices with solder pads lacking separate conductive elements, the light-emitting devices provided in this application have been verified to have better structural stability. Specifically, please refer to Table 1; Comparative Example 1 represents the structure of a light-emitting device with solder pads lacking separate conductive elements, and Example 1 represents a structure with solder pads lacking separate conductive elements. Figure 2 The light-emitting device shown in the solder pad state, Example 2 represents a similar device. Figure 2 The light-emitting device shown has a similar pad configuration but a larger number of conductive elements.

[0088] The thermal shock test conditions are as follows: the temperature range is -40℃ to 85℃, and after 600 cycles of temperature change, observe whether any light-emitting units fail the test (e.g., dark spots, bright spots, light-emitting units peeling off from the substrate, or cosmetic damage). The percentage of non-compliant light-emitting units is obtained by dividing the number of non-compliant units by the total number of light-emitting units.

[0089] Table 1

[0090]

[0091] According to the results in Table 1, in the thermal shock test, compared with Comparative Example 1, Examples 1 and 2 with pads having separate conductive elements had a lower rate of non-compliance in the test, and the setting of protective material can further reduce the rate of non-compliance in the light-emitting unit.

[0092] In summary, according to some embodiments of this application, the pads of the light-emitting device have multiple separate conductive elements. These multiple separate conductive elements can disperse the stress at the contact point between the pads and the substrate, reducing the situation where stress is excessively concentrated at the edge of the pads, thereby reducing the risk of substrate cracking or the light-emitting unit peeling off from the substrate.

[0093] While the embodiments and advantages of this application have been disclosed above, it should be understood that those skilled in the art can make modifications, substitutions, and refinements without departing from the spirit and scope of this application. Features between embodiments of this application can be freely combined and used as long as they do not violate the spirit of the invention or conflict with it. Furthermore, the scope of protection of this application is not limited to the processes, machines, manufacturing, material composition, apparatus, methods, and steps described in the specific embodiments of the specification. Those skilled in the art can understand from the disclosure of this application that current or future developed processes, machines, manufacturing, material composition, apparatus, methods, and steps can be used according to this application as long as they can perform substantially the same function or obtain substantially the same results in the embodiments described herein. Therefore, the scope of protection of this application includes the aforementioned processes, machines, manufacturing, material composition, apparatus, methods, and steps. The scope of protection of this application shall be determined by the scope of the appended claims. No embodiment or claim of this application needs to achieve all the purposes, advantages, and features disclosed in this application.

Claims

1. A light-emitting device, characterized in that, include: One substrate; A bonding pad is disposed on the substrate; A solder pad is disposed on the bonding pad, wherein the solder pad includes a plurality of discrete conductive elements; One light-emitting unit; A welding material is disposed between the light-emitting unit and the bonding pad, wherein the light-emitting unit is electrically connected to the bonding pad through the welding material and through the bonding pad; as well as A patterned insulating layer is disposed on the bonding pad, wherein the patterned insulating layer has a plurality of openings, and a plurality of conductive elements are respectively disposed in the plurality of openings, wherein a portion of the patterned insulating layer is disposed between the bonding pad and the conductive elements.

2. The light-emitting device as described in claim 1, characterized in that, The shape of the plurality of separate conductive elements is defined by the plurality of openings.

3. The light-emitting device as described in claim 1, characterized in that, At least one of the plurality of openings is a rectangle.

4. The light-emitting device as described in claim 3, characterized in that, The rectangle has rounded corners.

5. The light-emitting device as claimed in claim 1, characterized in that, At least one of the plurality of openings is circular.

6. The light-emitting device as claimed in claim 1, characterized in that, At least two of the plurality of openings have different dimensions.

7. The light-emitting device as claimed in claim 1, characterized in that, The size of the opening closer to the center of the light-emitting unit is larger than the size of the opening farther from the center of the light-emitting unit.

8. The light-emitting device as claimed in claim 1, characterized in that, The length of the solder pad is between 0.03 mm and 3 mm, and the width of the solder pad is between 0.03 mm and 3 mm.

9. The light-emitting device as claimed in claim 1, characterized in that, It also includes a protective material disposed on the substrate and covering the light-emitting unit, the solder pad and the bonding pad.

10. The light-emitting device as claimed in claim 9, characterized in that, The thickness of the protective material can be between 50 micrometers and 150 micrometers.

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