LED device
By separating and forming four areas of annular distribution on the substrate of the LED device, and reasonably laying the chips and pads, the problems of increasing size and occupancy area of LED devices in the prior art are solved, and the layout of larger chips is realized and Improvement of area efficiency.
Patent Information
- Application Number
- CN202421164378.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-24
- Publication Date
- 2025-02-14
- Estimated Expiration
- 2034-05-24
AI Technical Summary
In the process of increasing the chip size to meet the lighting and display function requirements, existing LED devices have increased the overall size and increased footprint, making it difficult to reasonably layout the chip to reduce the footprint of non-chip structures.
By forming four areas of annular distribution on the substrate, the first area and the second area, the first area is used to install the chip, the second area is used to set the second pad, and the second pad is connected by bonding wire The chip makes the area of the first pad as large as possible and the area of the second pad as small as possible, so as to reasonably arrange a larger chip.
This enables a larger chip to be laid out in LED devices of the same size, avoiding the problem of increasing the size of the LED device and increasing the area.
Smart Images
Figure CN222485216U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of LEDs, in particular to an LED device. Background Art
[0002] LED (Light Emitting Diode) devices are the key to modern lighting and display technology. With its high efficiency, energy saving, and long life, they are widely used in various fields such as indicator lighting, plant lighting, general lighting, automotive lighting, and display screens. At present, such LED devices require the size of the chip to be increased to meet the requirements of such LED devices for lighting, display, and other functions. However, as the chip size increases, according to the current chip layout mode, the overall size of the LED device will also increase, which increases the area occupied by the LED device. Utility Model Content
[0003] The utility model aims to provide an LED device with a reasonable chip layout, a large area occupied by the chip in the LED device, and a reduced area occupied by structures other than the chip in the LED device.
[0004] To achieve this purpose, the utility model adopts the following technical solutions:
[0005] Provided is an LED device, comprising:
[0006] A substrate, wherein the substrate has a mounting side surface, wherein the mounting side surface is divided by an isolation path to form four regions distributed in an annular manner around the center of the LED device, wherein the four regions along the circumferential direction are respectively a first region and a second region that are alternately arranged, wherein two of the first regions are diagonally arranged, and two of the second regions are diagonally arranged, wherein a first soldering pad is arranged in the first region, and a second soldering pad is arranged in the second region, and an area of the first soldering pad is larger than an area of the second soldering pad;
[0007] A chip, wherein the chip is fixed on the first pad, and a connecting electrode is arranged on a side of the chip away from the first pad;
[0008] a bonding wire, one end of which is connected to the connection electrode, and the other end of which is connected to the second pad;
[0009] A packaging colloid is provided on the mounting side, and the chip, the first pad, the second pad and the bonding wire are all packaged in the packaging colloid.
[0010] As an optional solution for the LED device, the area of the chip is S1, the area of the first pad is S2, and the ratio of S1 to S2 is 50%-90%.
[0011] As an optional solution for the LED device, the first soldering pad and the second soldering pad are both connected with connecting ribs;
[0012] The number of the connecting ribs is N, N≥3; or,
[0013] The connecting rib comprises a rib body and a cutting portion arranged on the rib body, and a width of the cutting portion is smaller than a width of the rib body.
[0014] As an optional solution for the LED device, all the connection ribs connected to the same first solder pad are distributed at an angle, and all the connection ribs connected to the same second solder pad are distributed at an angle.
[0015] As an optional solution for the LED device, a reflective cup is further provided on the mounting side, the first solder pad and the second solder pad are both located at the bottom of the reflective cup, the isolation path extends to the cup wall of the reflective cup, and the encapsulation colloid is filled in the reflective cup.
[0016] As an optional solution for the LED device, a plurality of connection parts are arranged between the first pad and the chip, and the plurality of connection parts are arranged at intervals.
[0017] As an optional solution of the LED device, at least one of the connecting portions is located at the center of the first soldering pad, and the remaining connecting portions are evenly distributed around the center of the first soldering pad; or,
[0018] All the connecting parts are distributed in the form of a triangle, a rectangle and a polygon.
[0019] As an optional solution for the LED device, a blocking protrusion protruding from the substrate is provided at the isolation path; or a blocking groove recessed in the substrate is provided at the isolation path.
[0020] As an optional solution for the LED device, the bonding wire includes a first inclined section, a flat section, and a second inclined section connected in sequence;
[0021] One end of the first inclined section away from the flat section is connected to the connection electrode, the first inclined section is inclined toward a side away from the second pad, and an angle between the first inclined section and the top surface of the chip away from the second pad is a1;
[0022] The flat section is inclined from the first inclined section toward the side where the second pad is located and toward the substrate, and the angle between the flat section and the horizontal plane is a2;
[0023] The second inclined section is inclined from the flat section toward the side where the second pad is located and toward the substrate, and an angle between the second inclined section and the substrate and close to the chip is a3;
[0024] Among them, a1>a3.
[0025] As an optional solution of the LED device, the vertical height of the first inclined section is h1, and h1 satisfies: 80 μm≤h1≤110 μm; and / or,
[0026] The vertical distance between the top of the first inclined section and the upper surface of the substrate is H, and H satisfies: 240 μm≤H≤290 μm; and / or,
[0027] a1 satisfies: 75°≤a1<90°; and / or,
[0028] a2 satisfies: 0°<a2≤15°; and / or,
[0029] a3 satisfies: 10°≤a3<35°; and / or,
[0030] A horizontal distance between one end of the first inclined section connected to the flat section and one end of the second inclined section connected to the second pad is y, and a horizontal length of the flat section is h2, where h2 satisfies: 0.3y≤h2≤0.5y.
[0031] As an optional solution for the LED device, a reinforcing ball is arranged on the top of the second soldering pad, and the second soldering pad is connected to the second inclined section through the reinforcing ball.
[0032] The beneficial effects of the utility model are as follows: the installation side of the substrate is separated by isolation paths to form four areas distributed in a ring along the center of the LED device, and the two diagonally distributed first areas are used to install the chip, and the other two diagonally distributed second areas are provided with second pads, and the second pads are used to connect the chip through bonding wires, so that the first area for fixing the chip can be made as large as possible (that is, the area of the first pad can be made as large as possible) to facilitate fixing chips of larger sizes, and the second area will be correspondingly reduced (that is, the area of the second pad can be made as small as possible), and the second pad as the part for connecting the bonding wire does not need to be laid out in too large an area, and a reasonable layout allows LED devices of the same size to be laid out with larger chips, avoiding an increase in the size of the LED device and an increase in the occupied area. BRIEF DESCRIPTION OF THE DRAWINGS
[0033] The utility model is further described in detail below based on the drawings and embodiments.
[0034] Figure 1 It is a three-dimensional schematic diagram of an LED device according to an embodiment of the utility model.
[0035] Figure 2 This is a top view of the LED device according to an embodiment of the present utility model.
[0036] Figure 3 It is a top view of the LED device according to an embodiment of the utility model (part of the connection part is shown).
[0037] Figure 4 It is a schematic diagram of the distribution of the connecting ribs of the LED device according to one embodiment of the utility model.
[0038] Figure 5 This is a schematic diagram of the distribution of connecting ribs of an LED device according to another embodiment of the utility model.
[0039] Figure 6 This is a top view of the LED device of an embodiment of the utility model (before the chip is fixed).
[0040] Figure 7 It is a three-dimensional schematic diagram of an LED device according to an embodiment of the utility model (illustrating the isolation convex part).
[0041] Figure 8 It is a three-dimensional schematic diagram of an LED device according to another embodiment of the utility model (illustrating the isolation groove).
[0042] Fig. 9 It is a cross-sectional view of the LED device according to the embodiment of the utility model.
[0043] Fig.10 This is a cross-sectional view of an LED device according to an embodiment of the present utility model (the angles of the first inclined section, the flat section and the second inclined section are marked).
[0044] In the figure:
[0045] 1. Substrate; 11. Mounting side; 12. Isolation channel; 13. Blocking protrusion; 14. Blocking groove; 2. First pad; 3. Second pad; 4. Chip; 41. Connecting electrode; 5. Bonding wire; 51. First inclined section; 511. First base section; 512. First arc transition section; 52. Flat section; 53. Second inclined section; 531. Second base section; 532. Second arc transition section; 6. Connecting rib; 61. Rib body; 62. Cutting part; 7. Reflection cup; 8. Connecting part; 9. Reinforcing ball. DETAILED DESCRIPTION
[0046] In order to make the technical problems solved by the utility model, the technical solutions adopted and the technical effects achieved clearer, the technical solutions of the embodiments of the utility model will be further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the utility model.
[0047] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0048] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.
[0049] Reference Figure 1 and Figure 2 As shown, an embodiment of the utility model provides an LED device, including a substrate 1, a chip 4, a bonding wire 5 and a packaging colloid (not shown in the figure), wherein the substrate 1 has a mounting side 11, and the mounting side 11 is separated by an isolation path 12 to form four areas distributed in a ring around the center of the LED device, and the four areas along the circumferential direction are respectively a first area and a second area alternately arranged, two first areas are diagonally distributed, and two second areas are diagonally distributed, a first pad 2 is arranged in the first area, and a second pad 3 is arranged in the second area, the area of the first pad 2 is larger than the area of the second pad 3, the chip 4 is fixed on the first pad 2, and a connecting electrode 41 is arranged on a side of the chip 4 away from the first pad 2, one end of the bonding wire 5 is connected to the connecting electrode 41, and the other end of the bonding wire 5 is connected to the second pad 3, the packaging colloid is arranged on the mounting side 11, and the chip 4, the first pad 2, the second pad 3 and the bonding wire 5 are all encapsulated in the packaging colloid.
[0050] The LED device of the embodiment of the utility model forms four areas distributed in a ring along the center of the LED device by dividing the installation side surface 11 of the substrate 1 by an isolation path 12, and the two diagonally distributed first areas are used to install the chip 4, and the other two diagonally distributed second areas are provided with second pads 3, and the second pads 3 are used to connect the chip 4 through the bonding wires 5, so that the first area for fixing the chip 4 can be made as large as possible (that is, the area of the first pad 2 can be made as large as possible) to facilitate fixing a chip 4 of a larger size, and the second area will be correspondingly reduced (that is, the area of the second pad 3 can be made as small as possible). The second pad 3, as the part connecting the bonding wire 5, does not need to be arranged in too large an area. Reasonable layout enables LED devices of the same size to be arranged with larger chips 4, thereby avoiding an increase in the size of the LED device and an increase in the occupied area.
[0051] Optionally, chip 4 is a vertical chip, and the electrodes of chip 4 are distributed on its top and bottom. The bottom electrode is used to connect chip 4 to the first pad 2 on substrate 1, and the top electrode (i.e., the connecting electrode 41 in this embodiment) is used to connect to the bonding wire 5.
[0052] In one embodiment, if Figure 2 and Figure 3 As shown (see attached Figure 1 ), there are four isolation paths 12, the four isolation paths 12 are arranged at an angle to each other, the four isolation paths 12 are connected at one end close to or located at the center of the LED device, and the four isolation paths 12 at one end away from the connection position all extend toward the end away from the center of the LED device. By connecting the four isolation paths 12 at one end close to or located at the center of the LED device, the two first areas and the two second areas are not directly connected, thereby preventing the first pad 2 and the second pad 3 from directly contacting and causing a short circuit.
[0053] In this embodiment, the area of the chip 4 is S1, the area of the first pad 2 is S2, and the ratio of S1 to S2 is 50%-90%. For example, S1 / S2 can be 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85% or 90%, etc.
[0054] In one embodiment, if Figure 4 As shown (refer to Figure 1 and Figure 2), the first pad 2 and the second pad 3 are both connected with a connecting rib 6. When manufacturing LED devices, they are generally manufactured in batches and then cut into single LED devices. A board is provided, and the first pad 2 and the second pad 3 are manufactured on the board. The adjacent first pads 2 and the second pad 3 are connected by the connecting rib 6. The chip 4 is fixed to the first pad 2, and then the chip 4 and the second pad 3 are connected by the bonding wire 5. Then, the packaging is performed by the packaging colloid, and finally, the LED device is cut into single LED devices along the periphery. When cutting, the connecting rib 6 is cut so that the first pad 2 and the second pad 3 in the single LED device are not connected.
[0055] Optionally, the number of the connecting ribs 6 connecting the first pads 2 and the number of the connecting ribs 6 connecting the second pads 3 are both N, where N≥3. By increasing the number of the connecting ribs 6 connecting the first pads 2 and the second pads 3, the width of each connecting rib 6 can be made narrower, which ensures that the connection strength of the adjacent first pads 2 remains unchanged or increases the connection strength while reducing the probability of burrs appearing after cutting a single connecting rib 6, because the narrower the width of the connecting rib 6, the fewer burrs will appear on its cross section after cutting, and the fewer burrs on the cross section of the connecting rib 6 can effectively improve the reliability of the LED device.
[0056] In other embodiments, the connecting rib 6 may be partially narrowed, for example, Figure 5 As shown, the connecting rib 6 includes a rib body 61 and a cutting portion 62 disposed on the rib body 61, and the width of the cutting portion 62 is smaller than the width of the rib body 61. By narrowing the position where the connecting rib 6 needs to be cut, the burrs on the cross section of the connecting rib 6 after cutting can also be reduced, thereby improving the reliability of the LED device. In this case, the number of connecting ribs 6 can be selected to be less than three, and narrowing the part will not reduce the connection strength of the connecting rib 6.
[0057] In addition, all the connecting ribs 6 connected to the same first pad 2 are distributed at an angle, and all the connecting ribs 6 connected to the same second pad 3 are distributed at an angle. By distributing the connecting ribs 6 connected to the same pad at an angle, it is convenient to distribute more connecting ribs 6 around the pad, improve the connection strength, and reduce the burrs on the cross section of the connecting ribs 6 after cutting. In this embodiment, each pad is connected to three connecting ribs 6, two of which are located on the same side of the pad, and the other connecting rib 6 is located on the other side of the pad, and the two sides of the connecting rib 6 are both facing the outside of the LED device, and the two sides are connected.
[0058] like Figure 1 and Figure 2As shown, the LED device of the embodiment of the utility model is also provided with a reflective cup 7, the reflective cup 7 protrudes from the installation side 11, the first soldering pad 2 and the second soldering pad 3 are both located at the bottom of the reflective cup 7, the isolation channel 12 extends to the cup wall of the reflective cup 7, and the packaging colloid is filled in the reflective cup 7, so that the chip 4 and the bonding wire 5 are both encapsulated in the reflective cup 7.
[0059] In addition, the chip 4 includes a red light chip and a green light chip, the height of the chip 4 is 130 μm-200 microns, and the depth of the reflective cup 7 is 320 μm-400 μm. For example, the height of the chip 4 can be 130 μm, 135 μm, 140 μm, 145 μm, 150 μm, 155 μm, 160 μm, 165 μm, 170 μm, 175 μm, 180 μm, 185 μm, 190 μm, 195 μm or 200 μm, etc. Preferably, the height of the chip 4 is 150 μm. The depth of the reflective cup 7 can be 320 μm, 330 μm, 340 μm, 350 μm, 360 μm, 370 μm, 380 μm, 390 μm or 400 μm, etc. Preferably, the depth of the reflective cup 7 is 360 μm.
[0060] In other embodiments, it is not limited to setting the reflective cup 7, and the chip 4 and the bonding wire 5 can also be directly packaged on the substrate 1 through the packaging colloid.
[0061] In one embodiment, if Figure 6 As shown (see attached Figure 1 and Figure 2 ), a plurality of connection parts 8 are arranged between the first pad 2 and the chip 4, and the connection parts 8 are used to fix the chip 4 on the first pad 2, and the plurality of connection parts 8 are arranged at intervals. Since the LED device needs to maintain a small size, and the size of the chip 4 needs to be designed to be large enough, a plurality of connection parts 8 are used to connect the chip 4 and the first pad 2, so that the problem of glue overflow due to a large amount of connection parts 8 in a whole block can be avoided, and the overflow of the connection parts 8 into the isolation channel 12 can be avoided, and the connection parts 8 can be further prevented from crossing the isolation channel 12 and contacting other pads, effectively preventing the formation of an erroneous electrical connection loop. In addition, the arrangement of a plurality of connection parts 8 can also effectively reduce the situation of the void formed between the first pad 2 and the chip 4, and ensure the stability of the fixation of the chip 4.
[0062] In this embodiment, the connecting portion 8 is silver paste.
[0063] Optionally, the connecting portion 8 can be formed by plastering one by one with a single plastering needle, or multiple plastering needles can be designed to complete the plastering at one time.
[0064] Optionally, one of the multiple connection portions 8 distributed on the first pad 2 is located at the center of the first pad 2, and the remaining connection portions 8 are evenly distributed around the central connection portion 8. In other embodiments, all the connection portions 8 can also be distributed in a triangular form, a rectangular form, or a polygonal form, etc.
[0065] In one embodiment, if Figure 7 As shown (see attached Figure 1 and Figure 2 ), a blocking convex portion 13 protruding from the substrate 1 is provided at the isolation path 12. By providing the blocking convex portion 13, the connection portion 8 can be further prevented from overflowing to the isolation path 12, thereby avoiding the formation of an erroneous electrical connection loop. In this embodiment, the height of the blocking convex portion 13 is 0.05mm-0.15mm, for example, the height of the blocking convex portion 13 can be 0.05mm, 0.06mm, 0.07mm, 0.08mm, 0.09mm, 0.1mm, 0.11mm, 0.12mm, 0.13mm, 0.14mm or 0.15mm, etc.
[0066] In other embodiments, it is not limited to setting the blocking protrusion 13. Figure 8 As shown (see attached Figure 1 and Figure 2 ), a blocking groove 14 recessed in the substrate 1 may be provided at the isolation channel 12. By providing the blocking groove 14, the overflowed connection portion 8 may be accommodated by the blocking groove 14, so as to prevent the connection portion 8 from contacting other pads, and effectively prevent the formation of an erroneous electrical connection loop. In this embodiment, the depth of the blocking groove 14 is 0.05 mm-0.1 mm, for example, the depth of the blocking groove 14 may be 0.05 mm, 0.06 mm, 0.07 mm, 0.08 mm, 0.09 mm or 0.1 mm, etc.
[0067] In one embodiment, if Fig. 9 and Fig.10 As shown (refer to Figure 1 and Figure 2 ), the bonding wire 5 includes a first inclined section 51, a flat section 52 and a second inclined section 53 connected in sequence, one end of the first inclined section 51 away from the flat section 52 is connected to the connection electrode 41 on the top surface of the chip 4, the first inclined section 51 is inclined toward the side away from the second pad 3, and the angle between the first inclined section 51 and the top surface of the chip 4 and away from the second pad 3 is a1; the flat section 52 is inclined from the first inclined section 51 toward the side where the second pad 3 is located and toward the substrate 1, and the angle between the flat section 52 and the horizontal plane is a2; the second inclined section 53 is inclined from the flat section 52 toward the side of the second pad 3 and toward the substrate 1, and the angle between the second inclined section 53 and the substrate 1 and close to the chip 4 is a3; wherein, a1>a3.
[0068] By tilting the lead wire of the first inclined section 51 toward the side away from the second pad 3, the horizontal distance between the end of the first inclined section 51 connected to one end of the gentle section 52 and the second pad 3 can be increased. When the first inclined section 51 is bent, there is a larger space to avoid stress concentration at the bending position. The downwardly inclined gentle section 52 is provided, which can not only reduce the arc height of the entire bonding wire 5, but also provide transition conditions for the second inclined section 53 to be smoothly introduced into the second pad 3, so that the second inclined section 53 can be connected to the second pad 3 at a smaller angle and in a gentler manner, thereby increasing the area where the second inclined section 53 is connected to the second pad 3. The stress at the connection position is reduced, thereby improving the reliability of the connection position; by setting the angle of the second inclined section 53 to be smaller than that of the first inclined section 51, the second inclined section 53 can be more smoothly introduced into the second pad 3 position and connected to the second pad 3, the shaping effect of the smooth section 52 and the second inclined section 53 will be better, and the area of the position where the second inclined section 53 is connected to the second pad 3 will be increased, which helps to reduce the stress concentration of the bonding wire 5 at the second pad 3 position, and the force on the welding position will be evenly distributed along a larger area, such as thermal stress, mechanical stress, etc., and will not be concentrated in a sharp corner or a small area, and the reliability is good.
[0069] In this embodiment, a1>a2, that is, the angle between the flat section 52 and the horizontal plane is smaller than the angle between the first inclined section 51 and the top surface of the chip 4 and away from the second pad 3. This design can reduce the height of the flat section 52, and can perform a transition downward tilting operation before the second inclined section 53 is led out, so as to avoid the second inclined section 53 needing a larger angle to be introduced to the second pad 3. After the flat section 52 slows down a certain angle, the second inclined section 53 can be as small as possible when the lead is tilted downward. The smaller the angle, the smoother the second inclined section 53 will be introduced to the second pad 3, that is, the outer wall of the second inclined section 53 will have more area to contact with the second pad 3 to achieve welding, increase the welding area, reduce stress concentration, and improve the stability of the welding position.
[0070] Optionally, a3 may satisfy: 10°≤a3<35°, for example, a3 may be 10°, 15°, 20°, 25°, 30°, 32° or 34°, etc. The smaller a3 is, the larger the area where the second inclined section 53 is fixed to the second pad 3 is, the higher the stability is, and the smaller the concentrated stress is.
[0071] Optionally, a2 may satisfy 0°<a2≤15°, for example, a2 may be 5°, 10° or 15°, etc. a2 is the inclination angle of the flat section 52, and the angle cannot be too large. If it is too large, the flat section 52 will be steeper, and a relatively small bending angle will be formed between the flat section 52 and the first inclined section 51, and stress concentration is likely to occur at this position, and the shaping effect of the flat section 52 will also be affected. Therefore, within the above-mentioned angle range, the arc height of the entire bonding wire 5 can be reduced, the shaping effect of the bonding wire 5 can be improved, and a large stress concentration can be effectively avoided at the bending position of the first inclined section 51, ensuring that the bonding wire 5 is not easily broken.
[0072] Optionally, a1 may satisfy 75°≤a1<90°, for example, a1 may be 75°, 80°, 85°, 88° or 89°, etc. a1 is the angle at which the first inclined section 51 is inclined toward the side away from the second pad 3. Within the above angle range, not only can the horizontal distance between the end of the first inclined section 51 connected to one end of the gentle section 52 and the second pad 3 be increased, so that the first inclined section 51 has a larger space when bending, but also the stress concentration of the first inclined section 51 at the bending position can be effectively prevented. If the angle a1 is too small, then the problem is that the angle at the bending position is too small when the gentle section 52 is led out after bending. If the angle at the bending position is too small, it is easy to form a large stress concentration problem, and the bonding wire 5 is easy to break at this position.
[0073] In addition, in addition to the angle, the speed of forming the bonding wire 5 is also very important. The combination of angle setting and the control of the forming speed of different sections can ensure the shaping effect of the bonding wire 5, smoothly weld with the pad, and reduce stress concentration.
[0074] Optionally, the molding speed of the first inclined section 51 is V1, the molding speed of the flat section 52 is V2, and the molding speed of the second inclined section 53 is V3, wherein V2<V1, V3<V1. By reducing the molding speed of the flat section 52 and the second inclined section 53, that is, the molding speed of the flat section 52 and the second inclined section 53 are both less than the molding speed of the first inclined section 51, and combining the angle of the second inclined section 53 is set to be less than the first inclined section 51, so that the second inclined section 53 can be more smoothly introduced to the second pad 3 position and connected to the second pad 3, the shaping effect of the flat section 52 and the second inclined section 53 will be better, and the area of the position where the second inclined section 53 is connected to the second pad 3 will be increased, which is helpful to reduce the stress concentration of the bonding wire 5 at the second pad 3 position, and the force on the welding position will be evenly distributed along a larger area, such as thermal stress, mechanical stress, etc., and will not be concentrated on a sharp corner or a small area, and the reliability is good, and the speed of the first inclined section 51 is accelerated, which can improve the manufacturing speed.
[0075] Optionally, the forming speed V2 of the flat section 52 and the forming speed V3 of the second inclined section 53 are equal, and the forming speed V2 of the flat section 52 may satisfy: 30% V1≤V2≤60% V1. For example, V2 may be 30% V1, 35% V1, 40% V1, 45% V1, 50% V1, 55% V1 or 60% V1, etc. By setting the forming speed of the flat section 52 and the forming speed of the second inclined section 53 to be consistent, the speed change can be avoided when the flat section 52 transitions to the second inclined section 53, thereby reducing the mechanical pulling force at the position of the second inclined section 53, so that the second inclined section 53 can be introduced to the position of the second pad 3 with a gentle and uniform force for welding and fixing; by setting the speed of the flat section 52 and the second inclined section 53 to the above speed range, the shaping effect of the flat section 52 and the second inclined section 53 can be improved while ensuring production efficiency, and the second inclined section 53 can be smoothly introduced to the position of the second pad 3 for welding, increasing the welding area between the second inclined section 53 and the second pad 3, improving stability, and reducing stress concentration. In actual manufacturing, the speeds of V2 and V3 can be lower, and the reliability will be higher when the speed is lower, but a certain production efficiency needs to be sacrificed, so the above speed is a more preferred range obtained after combining production efficiency and reliability.
[0076] In one embodiment, the first inclined section 51 includes a first base section 511 and a first arc transition section 512 connected in sequence, one end of the first base section 511 away from the first arc transition section 512 is connected to the connection electrode 41, and the first arc transition section 512 is used to connect the first base section 511 and the flat section 52, wherein the first base section 511 is a straight section, and the angle between the first base section 511 and the top surface of the chip 4 and away from the second pad 3 is a1. By setting the bending position of the first inclined section 51 to an arc structure, the arc structure can reduce the stress concentration at the bending position, thereby preventing the bonding wire 5 from breaking at this bending position.
[0077] The second inclined section 53 includes a second arc transition section 532 and a second base section 531 connected in sequence, the end of the second arc transition section 532 away from the second base section 531 is connected to the flat section 52, the end of the second base section 531 away from the second arc transition section 532 is connected to the second pad 3, the second base section 531 is a straight section, and the angle between the second base section 531 and the substrate 1 and close to the chip 4 is a3. By setting the position where the second inclined section 53 connects to the flat section 52 as an arc structure, the arc structure can reduce the stress concentration at the bending position, thereby preventing the bonding wire 5 from breaking at this bending position.
[0078] Optionally, the angle a4 of the first arc transition section 512 is 60°-90°, for example, the angle of the first arc transition section 512 can be 60°, 65°, 70°, 75°, 80°, 85° and 90°, etc. Preferably, the angle of the first arc transition section 512 is 90°. The angle a5 of the second arc transition section 532 is 130°-170°, for example, the angle of the second arc transition section 532 can be 130°, 135°, 140°, 145°, 150°, 155°, 160°, 165° and 170°, etc. Preferably, the angle of the second arc transition section 532 is 155°.
[0079] In one embodiment, the vertical height of the first inclined section 51 is h1, and h1 may satisfy 80 μm≤h1≤110 μm. For example, h1 may be 80 μm, 85 μm, 90 μm, 95 μm, 100 μm, 105 μm or 110 μm, etc. The height of the first inclined section 51 cannot be too high, otherwise the bonding wire 5 may be too high and exposed.
[0080] The vertical distance H between the top of the first inclined section 51 and the upper surface of the substrate 1 is H, and H may satisfy 240μm≤H≤290μm. For example, H may be 240μm, 245μm, 250μm, 255μm, 260μm, 265μm, 270μm, 275μm, 280μm, 285μm, 290μm, etc. The vertical distance H between the top of the first inclined section 51 and the upper surface of the substrate 1 is actually the sum of the height of the chip 4 and the overall arc height of the bonding wire 5. By controlling this height, it is possible to avoid the bonding wire 5 from being exposed after the LED device is packaged with the colloid to encapsulate the chip 4 and the bonding wire 5.
[0081] In one embodiment, the horizontal distance between one end of the first inclined section 51 connected to the flat section 52 and one end of the second inclined section 53 connected to the second pad 3 is y, and the horizontal length of the flat section 52 is h2, and h2 can satisfy 0.3y≤h2≤0.5y. For example, h2 can be 0.3y, 0.35y, 0.4y, 0.45y or 0.5y, etc. By setting the horizontal length of the flat section 52 to be no greater than half of the horizontal distance between one end of the first inclined section 51 connected to the flat section 52 and the second pad 3, the length of the second inclined section 53 can be as long as possible, and the angle of the second inclined section 53 is relatively small, so the length of the second inclined section 53 is relatively long. At a relatively low molding speed, the second inclined section 53 with a relatively long length is more gentle when introduced to the second pad 3, and the area attached to the second pad 3 will also be larger. After welding with the second pad 3, the stability is higher and the stress concentration is smaller.
[0082] Optionally, h2 may satisfy 200 μm≤h2≤600 μm, for example, h2 is 200 μm, 250 μm, 300 μm, 350 μm, 400 μm, 450 μm, 500 μm, 550 μm or 600 μm, etc. If h2 is too short, it is easy to become tight, which will increase the risk of the bonding wire 5 breaking, especially when it is subjected to external force or vibration. The shorter flat section 52 does not have enough elasticity to absorb and disperse these forces and cannot play a buffering role. If h2 is too large, that is, the length of the flat section 52 is too long, the angle between the second inclined section 53 and the substrate 1 will be too large, and the second inclined section 53 cannot be smoothly introduced to the position of the second pad 3 for welding with the second pad 3. The area of the welding position is also relatively small, and the stability will be greatly reduced. Therefore, setting h2 to the above length can not only enhance the buffering force of the flat section 52 and reduce the risk of breakage, but also make the angle between the second inclined section 53 and the substrate 1 relatively small, thereby improving the welding stability between the second inclined section 53 and the second pad 3.
[0083] In one embodiment, a reinforcing ball 9 is disposed on the top of the second pad 3, and the second pad 3 is connected to the second inclined section 53 through the reinforcing ball 9. By providing the reinforcing ball 9, the connection stability between the second inclined section 53 and the second pad 3 can be improved. The reinforcing ball 9, as a welding medium, can provide a more stable welding interface, and the reinforcing ball 9 can also fill the small gap between the second pad 3 and the bonding wire 5, thereby ensuring the tightness and reliability of welding and reducing the occurrence of welding defects.
[0084] Optionally, the width of the reinforcing ball 9 is 50 μm-100 μm, for example, the width of the reinforcing ball 9 can be 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, 75 μm, 80 μm, 85 μm, 90 μm, 95 μm or 100 μm, etc. The reinforcing ball 9 needs to have a sufficient width to provide a stable welding interface for the second inclined section 53 .
[0085] Optionally, the height of the reinforcing ball 9 is 20 μm-50 μm, for example, the height of the reinforcing ball 9 can be 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm and 50 μm, etc. The reinforcing ball 9 needs to have a sufficient height to melt a sufficient amount to fill the tiny gap between the second pad 3 and the bonding wire 5, so as to ensure the tightness and reliability of welding.
[0086] In the description of this specification, the description with reference to the terms "an embodiment", "example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example.
[0087] In addition, it should be understood that although this specification is described according to implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.
[0088] The technical principle of the present invention is described above in combination with specific embodiments. These descriptions are only for explaining the principle of the present invention and cannot be interpreted as limiting the protection scope of the present invention in any way. Based on the explanations here, technicians in this field can think of other specific implementation methods of the present invention without creative work, and these methods will fall within the protection scope of the present invention.
Claims
1. An LED device, characterized in that: include: A substrate, wherein the substrate has a mounting side surface, wherein the mounting side surface is divided by an isolation path to form four regions distributed in an annular manner around the center of the LED device, wherein the four regions along the circumferential direction are respectively a first region and a second region that are alternately arranged, wherein two of the first regions are diagonally arranged, and two of the second regions are diagonally arranged, wherein a first soldering pad is arranged in the first region, and a second soldering pad is arranged in the second region, and an area of the first soldering pad is larger than an area of the second soldering pad; A chip, wherein the chip is fixed on the first pad, and a connecting electrode is arranged on a side of the chip away from the first pad; a bonding wire, one end of which is connected to the connection electrode, and the other end of which is connected to the second pad; A packaging colloid is provided on the mounting side, and the chip, the first pad, the second pad and the bonding wire are all packaged in the packaging colloid.
2. The LED device according to claim 1, characterized in that: The area of the chip is S1, the area of the first pad is S2, and the ratio of S1 to S2 is 50%-90%.
3. The LED device according to claim 1, characterized in that: The first pad and the second pad are both connected with a connecting rib; The number of the connecting ribs is N, N≥3; or, The connecting rib comprises a rib body and a cutting portion arranged on the rib body, and a width of the cutting portion is smaller than a width of the rib body.
4. The LED device according to claim 3, characterized in that: All the connection ribs connected to the same first pad are distributed at an angle, and all the connection ribs connected to the same second pad are distributed at an angle.
5. The LED device according to claim 1, characterized in that: A reflector cup is also arranged on the installation side, the first solder pad and the second solder pad are both located at the bottom of the reflector cup, the isolation path extends to the wall of the reflector cup, and the packaging colloid is filled in the reflector cup.
6. The LED device according to any one of claims 1 to 5, characterized in that: A plurality of connection portions are arranged between the first pad and the chip, and the plurality of connection portions are arranged at intervals.
7. The LED device according to claim 6, characterized in that: At least one of the connection portions is located at the center of the first pad, and the remaining connection portions are evenly distributed around the center of the first pad; or, All the connecting parts are distributed in the form of a triangle, a rectangle and a polygon.
8. The LED device according to any one of claims 1 to 5, characterized in that: The isolation path is provided with a blocking protrusion protruding from the substrate; or, the isolation path is provided with a blocking groove recessed in the substrate.
9. The LED device according to any one of claims 1 to 5, characterized in that: The bonding wire comprises a first inclined section, a flat section and a second inclined section connected in sequence; One end of the first inclined section away from the flat section is connected to the connection electrode, the first inclined section is inclined toward a side away from the second pad, and an angle between the first inclined section and the top surface of the chip away from the second pad is a1; The flat section is inclined from the first inclined section toward the side where the second pad is located and toward the substrate, and the angle between the flat section and the horizontal plane is a2; The second inclined section is inclined from the flat section toward the side where the second pad is located and toward the substrate, and an angle between the second inclined section and the substrate and close to the chip is a3; Among them, a1>a3.
10. The LED device according to claim 9, characterized in that: The vertical height of the first inclined section is h1, and h1 satisfies: 80 μm≤h1≤110 μm; and / or, The vertical distance between the top of the first inclined section and the upper surface of the substrate is H, and H satisfies: 240 μm≤H≤290 μm; and / or, a1 satisfies: 75°≤a1<90°; and / or, a2 satisfies: 0°<a2≤15°; and / or, a3 satisfies: 10°≤a3<35°; and / or, A horizontal distance between one end of the first inclined section connected to the flat section and one end of the second inclined section connected to the second pad is y, and a horizontal length of the flat section is h2, where h2 satisfies: 0.3y≤h2≤0.5y.
11. The LED device according to claim 9, characterized in that: A reinforcing ball is disposed on the top of the second pad, and the second pad is connected to the second inclined section via the reinforcing ball.