Small-size LED packaging structure
By setting an extension section on the welding end bracket, the problem of inconsistent heating rate caused by the difference in heat capacity in small-sized LED packages is solved, which improves welding yield and product reliability, while maintaining the optical performance of the LED and reducing production and maintenance costs.
Patent Information
- Application Number
- CN202520389326.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-06
- Publication Date
- 2026-02-27
- Estimated Expiration
- 2035-03-06
AI Technical Summary
In the process of small-size LED packaging, the difference in heat capacity between the die bond end and the wire bond end leads to inconsistent heating rates, causing the "tombstone" phenomenon, which affects the soldering yield and product reliability.
An extension section is provided on the welding end support to make its heat capacity closer to that of the die bonded end, and it is arranged to extend into the white shell to avoid affecting the optical performance.
It effectively alleviates the problem of inconsistent heating rates, reduces the probability of "tombstone" phenomenon, improves welding yield and product reliability, maintains the optical performance of LEDs, and reduces production and after-sales maintenance costs.
Smart Images
Figure CN223957909U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to LED packaging technical field especially small size LED packaging structure. BACKGROUND
[0002] Small size LED has been widely applied in many fields due to its small size, easy integration and other advantages, such as mobile phone, tablet computer, wearable device and the like. In the traditional small size LED (length < 3mm) packaging process, the wafer is usually placed in the center position of the window. In this structure, the metal support of the die bonding end is designed to be relatively large in area in order to stably support the wafer and ensure good electrical connection, while the soldering end is mainly responsible for realizing electrical connection with external circuit and is relatively small in area.
[0003] In the reflow soldering process after LED packaging, due to the significant difference in heat capacity of the metal supports at both ends, it leads to inconsistent heating rates of the die bonding end and the soldering end in the heating process. The die bonding end has large heat capacity and relatively slow heating rate, while the soldering end has small heat capacity and relatively fast heating rate. The inconsistency of the heating rates will cause the surface tension of the solder to be unbalanced in the melting process. When the surface tension imbalance reaches a certain degree, it will cause the "monument" phenomenon, i.e. one end of the component will be tilted up. The occurrence of the "monument" problem will seriously affect the welding yield of the LED. The LED component with poor welding is prone to unstable electrical connection, increased contact resistance and other problems in the subsequent use process, thereby reducing the reliability of the entire product and increasing the after-sales maintenance cost and failure rate of the product.
[0004] In order to solve the "monument" problem, from the perspective of balancing the area of the support, the most direct idea is to increase the external area of the soldering end to make its heat capacity closer to that of the die bonding end, so as to achieve consistent heating rate in reflow soldering. However, under the existing technical conditions, directly increasing the external area of the soldering end has great disadvantages. As a light emitting component, the optical properties of the LED, such as light emitting angle, brightness uniformity and the like, are closely related to the packaging structure. Increasing the external area of the soldering end will change the overall structural layout of the LED, thereby affecting the propagation and scattering of light and ultimately damaging the optical performance of the LED. Therefore, developing a design scheme that can effectively balance the area of the support and avoid the occurrence of the "monument" phenomenon without damaging the optical performance of the LED has become a key problem to be solved in the current small size LED packaging field. This not only helps to improve the production yield and product reliability of the small size LED, but also further expands its application in application scenarios with strict requirements on optical performance. SUMMARY
[0005] The utility model discloses a small size LED packaging structure, which is aimed at solving the "monument" phenomenon generated in the welding process to improve the production yield and product reliability of small size LED.
[0006] The utility model discloses a technical problem solving technical scheme as follows:
[0007] Small size LED packaging structure, including,
[0008] Fixed end support,
[0009] LED wafer is arranged on the fixed end support,
[0010] Welding end support,
[0011] Gold wire, both ends are electrically connected with the LED wafer and the welding end support respectively,
[0012] White shell, the fixed end support and the welding end support are installed on the white shell, and the LED wafer is exposed at the center position of the window,
[0013] Wherein, the welding end support is provided with extension expansion part, and the extension expansion part extends to the inside of the white shell and is arranged away from the window area.
[0014] The utility model also has the following technical features:
[0015] In an embodiment of the utility model, the projection area proportion difference of the welding end support and the fixed end support along the first direction is less than or equal to 30%, and the first direction is the window face direction perpendicular to the window.
[0016] In an embodiment of the utility model, the extension expansion part is the extension strip provided with the welding end support side, and the extension strip is arranged in parallel with the length direction of the welding end support.
[0017] In an embodiment of the utility model, the extension strip is arranged on both sides of the welding end support.
[0018] In an embodiment of the utility model, the extension strip is provided with wave surface.
[0019] In an embodiment of the utility model, the extension strip is provided with convex, and multiple convexes are arranged at intervals.
[0020] In an embodiment of the utility model, the window is a whole rectangular hole or a waist type hole, and the extension strip is arranged along the length direction of the window.
[0021] In an embodiment of the utility model, the fixed end support and the welding end support are arranged at intervals, one end of the fixed end support and the welding end support protrudes out of the white shell and forms a welding surface for welding with the circuit board welding point, and the welding surfaces of the fixed end support and the welding end support are coplanar.
[0022] Compared with the prior art, the utility model has the beneficial effects that: by setting the extension expansion part on the welding end support, the overall area of the welding end support is increased, and the heat capacity is increased, so that the problem of inconsistent temperature rising rate caused by the difference in heat capacity of the welding end support and the fixed end support during reflow soldering is effectively alleviated, the solder surface tension is balanced, the probability of the "monument" phenomenon of the component is greatly reduced, and the welding yield is significantly improved.
[0023] The extension expansion part extends into the white shell and is arranged away from the window area, avoiding the direct influence of the increase in the area of the welding end support on the optical properties of the LED, ensuring that the LED maintains good performance in terms of light emitting angle, brightness uniformity, and other aspects, and meeting the requirements of application scenarios with strict optical performance requirements.
[0024] As the "monument" problem is solved, the hidden dangers such as unstable electrical connection and increased contact resistance caused by poor welding are reduced, the product is more stable and reliable during long-term use, the after-sales maintenance cost and failure rate of the product are reduced, and the service life of the product is prolonged; this structural design improves the welding end support through the extension expansion part without changing the basic framework of the overall package, has the advantages of simple structure and easy implementation, is conducive to improving production efficiency, reducing production cost, and enhancing the competitiveness of the product in the market. BRIEF DESCRIPTION OF DRAWINGS
[0025] Figure 1a is a structural schematic view of an LED module in the prior art;
[0026] Figure 1b is a structural schematic view of a die bonding end and a wire bonding end in the prior art;
[0027] Figure 2 and Figure 3 are two perspective structural schematic views of a small-size LED package structure in an embodiment of the utility model;
[0028] Figure 4 is a top view of a small-size LED package structure in an embodiment of the utility model;
[0029] Figure 5 is a front view of a small-size LED package structure in an embodiment of the utility model;
[0030] Figure 6The structure schematic view of the fixed end support and the welding end support in one embodiment of the present utility model;
[0031] Figure 7 The top view of the fixed end support and the welding end support in one embodiment of the present utility model and prior art;
[0032] Figure 8 The light intensity distribution curve diagram of the LED module in one embodiment of the present utility model;
[0033] BRIEF DESCRIPTION OF DRAWINGS
[0034] 10, fixed end support;
[0035] 20, welding end support; 21, extension expansion part;
[0036] 30, white shell; 31, window;
[0037] 40, gold wire;
[0038] 50, LED wafer. DETAILED DESCRIPTION
[0039] The present utility model will be described by specific embodiments, and those skilled in the art can easily understand other advantages and effects of the present utility model from the disclosure of the specification. The present utility model can also be implemented or applied by different specific embodiments, and the details in the specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present utility model.
[0040] The drawings provided in the embodiments only illustrate the basic concept of the present utility model in a schematic manner, and only show the components related to the present utility model in the drawings, not the number, shape and size of the components in actual implementation. The shape, number and ratio of each component in actual implementation can be changed arbitrarily, and the component layout pattern can be more complex.
[0041] It should be noted that, referring to Figure 1a and Figure 1bAs shown in the conventional small size LED (length < 3mm) packaging process, the wafer is usually placed in the center of the window. In this structure, the metal support of the die-bonding end is designed to be relatively large in order to stably support the wafer and ensure good electrical connection. The wire-bonding end is mainly responsible for electrical connection with external circuits, and the area is relatively small. During the reflow soldering process after LED packaging, due to the significant difference in heat capacity of the metal supports at both ends, the heating rates of the die-bonding end and the wire-bonding end are inconsistent. The heat capacity of the die-bonding end is large, and the heating is relatively slow. The heat capacity of the wire-bonding end is small, and the heating is relatively fast. This inconsistency in heating rate can cause the surface tension of the solder to become unbalanced during melting. When the surface tension imbalance reaches a certain level, it can cause the "monument" phenomenon, i.e., one end of the component will be tilted. The occurrence of the "monument" problem can seriously affect the welding yield of the LED. LED components with poor welding are prone to unstable electrical connection, increased contact resistance, and other problems during subsequent use, which can reduce the reliability of the entire product, increase the cost of after-sales maintenance and failure rate. To solve this problem, a small size LED packaging structure is proposed, which includes: a fixed end support 10; an LED wafer 50 arranged on the fixed end support 10; a soldering end support 20; a gold wire 40 electrically connected to the LED wafer 50 and the soldering end support 20 at both ends; a white shell 30 with a window 31; the fixed end support 10 and the soldering end support 20 are installed on the white shell 30, and the LED wafer 50 is exposed at the center of the window 31; wherein the soldering end support 20 is provided with an extension 21, and the extension 21 extends to the inside of the white shell 30 and is arranged away from the window 31 area.
[0042] In an embodiment, referring to Figure 4 and Figure 6 , the extension 21 is arranged on the soldering end support 20. In actual design, it can be of various styles. In actual arrangement, the extension 21 should be avoided from being exposed in the window 31 area to avoid blocking the light path of the wafer or changing the light angle and affecting the optical performance of the LED module.
[0043] In an embodiment, referring to Figure 6 , the projection area ratio difference of the soldering end support 20 and the fixed end support 10 along the first direction f is less than or equal to 30%, and the first direction f is perpendicular to the window surface direction of the window 31.
[0044] It should be understood that the projection area of the soldering end support 20 in the first direction f is 0.1mm 2 . For example, the projection area of the fixed end support 10 in the first direction f is 0.07-0.13mm 2 .
[0045] It should also be understood that, referring to Figure 6 , the projection area s2 and s1 of the welding end support 20 and the fixed end support 10 along the first direction f are the shadow parts in the figure, and the proportional difference of the projection area s2 and s1 of the shadow part is less than or equal to 30%, excluding the projection area of the lower bending part of the welding end support 20 and the fixed end support 10 along the first direction f.
[0046] In an embodiment, the length of the LED module is less than 3mm.
[0047] In some embodiments, taking an LED with a length of 2.5mm as an example, the L-shaped metal extension 21 is additionally arranged inside the white shell 30 at the welding end support 20, so that the projection area is increased from 0.12mm 2 to 0.16mm 2 , the projection area of the die bonding end is 0.18mm 2 , and the proportional difference is 11.1%. After reflow soldering test, the monument rate is reduced from 15% of the traditional design to 0.3%, and the light intensity distribution curve is consistent with the original design, referring to Figure 8 , the dashed line in the figure represents the light intensity distribution curve when the wafer 50 is eccentric, and the solid line in the figure represents the light intensity distribution curve when the wafer 50 is in the center position.
[0048] In an embodiment, the extension 21 is an extension strip arranged on the side of the welding end support 20, and the extension strip is arranged in parallel with the length direction of the welding end support 20.
[0049] In an embodiment, referring to Figure 6 and Figure 7 , the extension strip is arranged on both sides of the welding end support 20.
[0050] In an embodiment, in order to further increase the surface area of the extension 21, a wave surface is arranged on the extension strip.
[0051] In another embodiment, a sawtooth surface can be arranged on the extension strip to increase the area of the extension strip.
[0052] In yet another embodiment, a protrusion is arranged on the extension strip, and a plurality of protrusions are arranged at intervals.
[0053] In yet another embodiment, the thickness of the extension strip can be thickened according to actual design.
[0054] In actual design of the LED module, the window 31 is a whole rectangular hole or a waist-shaped hole, and the extension strip is arranged along the length direction of the window 31.
[0055] In an embodiment, the extension strip is arranged to extend inside the length direction of the window 31, so as to avoid the extension strip from being exposed in the window 31.
[0056] In an embodiment, referring to Figure 5 , the fixed end support 10 and the welding end support 20 are arranged to be spaced apart, and the fixed end support 10 and the welding end support 20 are arranged to protrude out of the white shell 30 and form welding surfaces for welding with the circuit board welding points, and the welding surfaces of the fixed end support 10 and the welding end support 20 are coplanar.
[0057] In summary, the extension expansion part 21 is arranged on the welding end support 20, the overall area of the welding end support 20 is increased, and the heat capacity is increased, so that the problem of inconsistent temperature rising rate caused by the difference in heat capacity of the welding end support 20 and the fixed end support 10 during reflow soldering is effectively alleviated, the solder surface tension is balanced, the probability of the phenomenon of "monument" of the element is greatly reduced, and the welding yield is significantly improved.
[0058] The extension expansion part 21 extends into the inside of the white shell 30 and is arranged away from the window 31 area, avoiding the direct influence of the increase of the area of the welding end support 20 on the optical properties of the LED, ensuring that the LED maintains good performance in terms of light emitting angle, brightness uniformity and the like, and meeting the requirements of application scenarios with strict optical performance requirements.
[0059] Since the "monument" problem is solved, the hidden troubles such as unstable electrical connection and increased contact resistance caused by poor welding are reduced, the product is more stable and reliable during long-term use, the after-sales maintenance cost and failure rate of the product are reduced, and the service life of the product is prolonged. The structure design does not change the basic framework of the whole package, and the welding end support 20 is improved by the extension expansion part 21, which has the advantages of simple structure and easy implementation, is conducive to improving production efficiency, reducing production cost, and enhancing the competitiveness of the product in the market.
[0060] For those skilled in the art, it is obvious that the utility model is not limited to the details of the above exemplary embodiments, and can be realized in other specific forms without departing from the spirit or basic characteristics of the utility model. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting, the scope of the utility model is defined by the appended claims rather than the above description, and therefore all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the utility model. Any reference signs in the claims should not be regarded as limiting the claims involved.
[0061] Furthermore, it should be understood that although the specification is described in terms of embodiments, not every embodiment includes every feature or implementation described herein. The specification can include implicit combinations of explicitly mentioned features and / or implicit combinations of implicitly mentioned features. Such combinations are also expressly included within the scope of the specification and an embodiment.
Claims
1. A small size LED package structure, characterized in that, The utility model relates to a LED lamp, which comprises: a fixed end support (10); an LED wafer (50) arranged on the fixed end support (10); a soldering end support (20); a gold wire (40) electrically connected to the LED wafer (50) and the soldering end support (20) at both ends; a white shell (30) with a window (31) formed on the top, the fixed end support (10) and the soldering end support (20) being mounted on the white shell (30) and the LED wafer (50) being exposed at the center of the window (31); wherein, the soldering end support (20) is provided with an extension expansion part (21) extending to the inside of the white shell (30) and arranged away from the window (31) area.
2. The small-size LED package structure according to claim 1, wherein, The projection area ratio difference of the soldering end support (20) and the fixed end support (10) in the first direction is less than or equal to 30%, and the first direction is the direction perpendicular to the window surface of the window (31).
3. The small-size LED package structure according to claim 1, wherein, The extension expansion part (21) is an extension strip arranged on the side of the soldering end support (20), and the extension strip is arranged in parallel with the length direction of the soldering end support (20).
4. The small-size LED package structure according to claim 3, wherein, The extension strip is arranged on both sides of the soldering end support (20).
5. The small-size LED package structure according to claim 3, wherein, The extension strip is provided with a wave surface.
6. The small-size LED package structure according to claim 3, wherein, The extension strip is provided with a plurality of protrusions arranged at intervals.
7. The small-size LED package structure according to claim 3, wherein, The window (31) is a whole rectangular hole or a waist-shaped hole, and the extension strip is arranged along the length direction of the window (31).
8. The small-size LED package structure according to claim 1, wherein, The fixed end support (10) and the soldering end support (20) are arranged at intervals, one end of the fixed end support (10) and the soldering end support (20) protruding out of the white shell (30) and forming a soldering surface for soldering with a circuit board, and the soldering surfaces of the fixed end support (10) and the soldering end support (20) are coplanar.