Bonding wire structure and packaging structure
By using a segmented composite structure design and bonding wires made of different materials, the problem of traditional bonding wire structures being unable to balance welding quality and cost is solved, resulting in effective cost reduction and improved welding reliability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HONGLI ZHIHUI GRP CO LTD
- Filing Date
- 2025-04-30
- Publication Date
- 2026-05-08
AI Technical Summary
Traditional bonding wire structures struggle to reduce costs while maintaining welding quality, and bonding wire structures made of a single material cannot balance cost-effectiveness and reliability.
The design employs a segmented composite structure. The first and second welding points use high-performance materials, while the intermediate connecting section uses lower-performance but lower-cost materials. The annealing section and the line-arc transition section also use different materials to ensure welding quality and reduce costs.
While ensuring welding quality and reliability, costs were significantly reduced, meeting product production requirements.
Smart Images
Figure CN224218814U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of semiconductor technology, specifically to a bonding wire structure and packaging structure. Background Technology
[0002] Bonding wires are the internal leads between the chip and the frame, and are one of the fundamental structures of integrated circuit packaging. As the demand for both the quantity and quality of integrated circuits continues to increase, the requirements for bonding wire structures are also becoming more stringent. Traditional bonding wire structures typically use a single material, such as gold, gold alloys, silver, silver alloys, copper, copper alloys, iron, iron alloys, aluminum, or aluminum alloys. This inevitably leads to a trade-off between cost and soldering quality. To ensure soldering quality, higher-performance materials are needed, but these are usually more expensive. Using mixed materials or lower-performance materials can reduce costs, but this also reduces soldering quality, making it difficult to guarantee product reliability. Therefore, single-material bonding wire structures struggle to balance cost-effectiveness and reliability.
[0003] The bonding wire structure is mainly used to solve the electrical connection between the chip end and the frame end. The connection area between the bonding wire structure and the chip end and the frame end is closely related to the welding quality. How to reduce costs while ensuring welding quality is a technical problem that urgently needs to be solved. Utility Model Content
[0004] In view of this, the embodiments of this application aim to provide a bonding wire structure and packaging structure to solve the problems of not being able to balance welding quality and welding cost in the prior art.
[0005] This application provides a bonding wire structure, including a first solder joint portion, a second solder joint portion, and an intermediate connecting segment, wherein the two ends of the intermediate connecting segment are respectively connected to the first solder joint portion and the second solder joint portion;
[0006] The first solder joint portion and the second solder joint portion are made of a first conductive material, and at least a portion of the intermediate connecting section is made of a second conductive material. The first conductive material is different from the second conductive material.
[0007] In some embodiments, the oxidation resistance of the first conductive material is greater than that of the second conductive material.
[0008] In some embodiments, the first solder joint portion is a spherical solder joint, and the second solder joint portion is a wedge-shaped solder joint.
[0009] In some embodiments, the intermediate connecting segment includes a line arc transition segment and an annealed segment connected to each other. The annealed segment connects to the first solder joint portion, and the line arc transition segment connects to the second solder joint portion. The material of the annealed segment is a third conductive material, and at least a portion of the material of the line arc transition segment is the second conductive material. The third conductive material is different from the second conductive material.
[0010] In some embodiments, the oxidation resistance of the third conductive material is greater than that of the second conductive material; and / or, the third conductive material is the same as the first conductive material.
[0011] In some embodiments, the length of the annealing section is 30 μm to 150 μm.
[0012] In some embodiments, the ratio of the portion of the intermediate connecting segment made of the second conductive material to the length of the intermediate connecting segment is greater than or equal to 50%.
[0013] In some embodiments, the first conductive material is gold, and the second conductive material is at least one of gold alloy, silver, copper, iron, and aluminum.
[0014] In some embodiments, the first conductive material and the second conductive material are gold alloys, and the gold content in the first conductive material is greater than the gold content in the second conductive material.
[0015] An embodiment of this application also provides a packaging structure including at least one pair of solder pads, with the aforementioned bonding wire structure soldered between each pair of solder pads.
[0016] This application provides a bonding wire structure and a packaging structure. The bonding wire structure includes a first solder joint portion, a second solder joint portion, and an intermediate connecting section. The two ends of the intermediate connecting section are respectively connected to the first solder joint portion and the second solder joint portion. The first solder joint portion and the second solder joint portion are made of a first conductive material, and at least a portion of the intermediate connecting section is made of a second conductive material. The first conductive material and the second conductive material are different. In this application, the material of at least a portion of the intermediate connecting section is different from the materials of the first solder joint portion and the second solder joint portion. Since the first solder joint portion and the second solder joint portion are closely related to the welding quality, high-priced, high-performance materials can be selected to ensure welding quality and meet the requirements of welding reliability. However, the intermediate connecting section has little impact on welding quality, so lower-priced, slightly lower-performance materials can be selected. This ensures welding quality while reducing costs and meeting product production requirements. Attached Figure Description
[0017] Figure 1This is a schematic diagram of a packaging structure including a bonding wire structure provided in an embodiment of this application.
[0018] Figure 2 This is a schematic diagram of the structure of a bonding wire forming a bonding wire structure according to an embodiment of this application.
[0019] The attached figures are labeled as follows:
[0020] 100 - Substrate; 101 - First solder pad; 200 - Chip; 201 - Second solder pad; 301 - First solder joint portion; 302 - Intermediate connection section; 312 - Annealing section; 322 - Linear arc transition section; 303 - Second solder joint portion. Detailed Implementation
[0021] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0022] One embodiment of this application provides a bonding wire structure that can be used to electrically connect two solder pads. Figure 1 This is a schematic diagram of a packaging structure including a bonding wire structure provided in an embodiment of this application. Figure 1 As shown, the bonding wire structure includes a first solder joint portion 301, a second solder joint portion 303, and an intermediate connecting segment 302, which are sequentially connected to form an integral structure. Specifically, the intermediate connecting segment 302 is located between the first solder joint portion 301 and the second solder joint portion 303, and its two ends are respectively connected to the first solder joint portion 301 and the second solder joint portion 303.
[0023] In some embodiments, the bonding wire structure is formed by ball-wedge bonding process, in which the first solder joint portion 301 is a spherical solder joint (also known as a ball-bonding area), and the first solder joint portion 301 is generally spherical or quasi-spherical, and the second solder joint portion 303 is a wedge-shaped solder joint (or flat solder joint), and the second solder joint portion 303 is wedge-shaped or quasi-wedge-shaped.
[0024] Furthermore, the first solder joint portion 301 and the second solder joint portion 303 are made of a first conductive material, while at least a portion of the intermediate connecting section 302 is made of a second conductive material. The first conductive material and the second conductive material are different. That is to say, this application designs the bonding wire structure in segments. The material of at least a portion of the intermediate connecting section 302 is different from the material of the first solder joint portion 301 and the second solder joint portion 303. Since the first solder joint portion 301 and the second solder joint portion 303 are closely related to the welding quality, they can be made of high-priced, high-performance materials to ensure welding quality and meet the requirements of welding reliability. However, the intermediate connecting section 302 has little impact on welding quality, so it can be made of lower-priced, slightly lower-performance materials. In this way, welding quality can be guaranteed while reducing costs and meeting the production requirements of the product.
[0025] For example, the first conductive material can be gold. Gold is expensive but has excellent performance. When the materials of the first solder joint portion 301 and the second solder joint portion 303 are gold, problems such as poor ball burning, broken wires, and cold solder joints can be solved, thereby improving the welding quality, ensuring welding stability, and guaranteeing the performance and stability of the product. In this case, the second conductive material can be a conductive material other than gold (pure gold), such as at least one of gold alloys, silver, copper, iron, and aluminum. The cost of these materials is significantly lower than that of gold, but their performance is inferior to that of gold. When at least a portion of the intermediate connecting section 302 is a conductive material other than gold, the cost can be significantly reduced. Furthermore, since the intermediate connecting section 302 has a limited impact on the welding quality, even if the entire intermediate connecting section 302 is replaced with a low-cost conductive material, the welding quality will not be significantly affected. It can be seen that the bonding wire structure in this application adopts a segmented composite structure material design, which can reduce costs while ensuring welding stability and meeting the production needs of the product.
[0026] In some embodiments, both the first conductive material and the second conductive material can be gold alloys, and the gold content in the first conductive material is greater than the gold content in the second conductive material (in this document, even alloys composed of the same metal are considered different materials if their metal contents are not exactly the same). This also balances the issues of welding quality and cost. For example, the first conductive material can be a gold alloy with a gold content of 80%, and the second conductive material can be a gold alloy with a gold content of 50%.
[0027] In some embodiments, the first conductive material may be gold, and the second conductive material may be a gold alloy. For example, the first conductive material may be gold, and the second conductive material may be a gold alloy with a gold content of 50%.
[0028] It should be noted that the first conductive material is not necessarily gold or a gold alloy. In some low-end products, the first conductive material can also be silver or other conductive materials, while the second conductive material can be at least one of copper, aluminum, iron, or other conductive materials. In other words, this application does not limit the specific materials of the first and second conductive materials, as long as they are different materials. This allows for matching appropriate materials according to the corresponding welding requirements, enabling the bond wire structure to balance welding quality and cost.
[0029] In some embodiments, when selecting the first conductive material and the second conductive material, the oxidation resistance of the first conductive material and the second conductive material can be considered. Generally speaking, the oxidation resistance of the first conductive material needs to be greater than that of the second conductive material. This is to ensure that the first solder joint portion 301 and the second solder joint portion 303 will not be oxidized during high-temperature welding, thereby avoiding problems such as poor ball burning and cold solder joints.
[0030] Of course, in some embodiments, other principles can be used to select the first conductive material and the second conductive material. For example, when both the first conductive material and the second conductive material are pure metal materials, a metal with better element stability or ductility can be selected as the first conductive material.
[0031] Please continue reading. Figure 1 The intermediate connecting section 302 includes a line arc transition section 322 and an annealed section 312 connected to each other. The annealed section 312 is connected to the first solder joint portion 301, and the line arc transition section 322 is connected to the second solder joint portion 303. The material of the annealed section 312 is a third conductive material, and at least a portion of the material of the line arc transition section 322 is a second conductive material. The third conductive material is different from the second conductive material. Since the annealing section 312 is close to the first weld point 301, the welding wire in the annealing section 312 also bears more heat when the cleaver forms the sintered ball of the first weld point 301, resulting in increased internal pressure and a tendency to break. Therefore, at least a portion of the annealing section 312 and the arc transition section 322 are designed to be made of different materials. Since the annealing section 312 is also related to the welding quality, a high-priced, high-performance material can be selected to ensure welding quality and meet the requirements of welding reliability. The arc transition section 322 has little impact on welding quality, so a lower-priced, slightly lower-performance material can be selected. This way, welding quality can be guaranteed while reducing costs and meeting the production requirements of the product.
[0032] For example, the third conductive material can be gold. Gold is expensive but has excellent performance. When the material of the annealing section 312 is gold, problems such as breakage of the annealing section 312 can be solved, thereby improving welding quality, ensuring welding stability, and guaranteeing the performance and stability of the product. In this case, the second conductive material can be a conductive material other than gold (pure gold), such as at least one of gold alloys, silver, copper, iron, and aluminum. These materials have a significantly lower cost than gold, but their performance is inferior to gold. When at least a portion of the arc transition section 322 is a conductive material other than gold, the cost can be significantly reduced. Furthermore, since the arc transition section 322 has a limited impact on welding quality, even if the entire arc transition section 322 is replaced with a low-cost conductive material, it will not significantly affect the welding quality. It can be seen that further segmenting the intermediate connecting section 302 and designing different sections with different materials can further reduce costs while ensuring welding stability, thus meeting the production requirements of the product.
[0033] In some embodiments, the length of the annealed section 312 is relatively short, for example, it can be 30μm to 150μm. Therefore, even if the annealed section 312 is made of a more expensive material, it will not increase the cost of the bonding wire structure too much.
[0034] In some embodiments, the third conductive material and the second conductive material can both be gold alloys. In this case, the gold content in the third conductive material is greater than the gold content in the second conductive material, which can also balance the issues of welding quality and cost.
[0035] In some embodiments, the third conductive material may be the same as the first conductive material. For example, both the first and third conductive materials may be gold, and the second conductive material may be a conductive material other than gold, such as at least one of silver, copper, iron, and aluminum; the first, second, and third conductive materials may also be gold alloys, and the first and third conductive materials may have the same gold content, with the gold content in both materials being greater than that in the second conductive material.
[0036] In some embodiments, the third conductive material may be different from the first conductive material. For example, the first conductive material may be gold or a gold alloy, the third conductive material may be silver or a silver alloy, and the second conductive material may be a conductive material other than gold and silver, such as at least one of copper, iron, and aluminum or an alloy thereof; the first, second, and third conductive materials may also all be gold alloys, and the gold content in the first conductive material is greater than the gold content in the third conductive material, and the gold content in the third conductive material is greater than the gold content in the second conductive material.
[0037] Furthermore, the ratio of the portion of the intermediate connecting section 302 made of the second conductive material to the length of the intermediate connecting section 302 is greater than or equal to 50%. For example, the entire arc transition section 322 can be made of the second conductive material, the first solder joint portion 301 and the second solder joint portion 303 can be made of the first conductive material, and the annealed section 312 can be made of the third conductive material. In this case, the ratio of the length of the arc transition section 322 to the total length of the first solder joint portion 301, the second solder joint portion 303, the annealed section 312, and the arc transition section 322 (i.e., the entire bond wire structure) is greater than or equal to 50%. This ensures that the portion of the intermediate connecting section 302 made of the second conductive material is long enough, thus better balancing cost and welding quality.
[0038] In some embodiments, the arc transition section 322 is not limited to being entirely made of the second conductive material. Of course, the arc transition section 322 may be made of only part of the second conductive material, while the other parts may be made of the third conductive material or the first conductive material. Examples will not be given here.
[0039] In some embodiments, the intermediate connecting segment 302 may be entirely made of the second conductive material. Of course, the intermediate connecting segment 302 may be made of only part of the second conductive material, while the other parts may be made of the third conductive material or the first conductive material. Examples will not be given here.
[0040] Based on this, one embodiment of this application also provides a packaging structure, such as an LED packaging structure. Figure 1 As shown, the package structure includes at least one pair of solder pads, and the bonding wire structure described above is soldered between each pair of solder pads. The bonding wire structure is used to realize the electrical connection of the corresponding pair of solder pads.
[0041] Please continue reading. Figure 1 A pair of bonding pads includes a first bonding pad 101 and a second bonding pad 201, wherein the first bonding pad 101 is located on the chip 200 and the second bonding pad 201 is located on the substrate 100. The bonding wire structure is used to realize the electrical connection between the chip 200 and the substrate 100.
[0042] In some embodiments, the two pads in each pair of pads may be located on two chips 200 respectively, and the bonding wire structure is used to realize the electrical connection between the two chips 200.
[0043] Figure 2 This is a schematic diagram of the structure of a bonding wire forming a bonding wire structure according to an embodiment of this application. Figure 2 As shown, the bonding wires forming the bonding wire structure typically include alternating first segments ( Figure 2 The green part in the middle), the second paragraph ( Figure 2 (the red part in the middle) and the third paragraph ( Figure 2(The yellow part in the image). The first segment is made of a first conductive material and is used to form the first solder joint 301 and the second solder joint 303; the second segment is made of a third conductive material and is used to form the annealed segment 312; the third segment is made of a second conductive material and is used to form the arc transition segment 322.
[0044] It should be understood that the amount of solder wire used in the first solder joint 301, the second solder joint 303, the annealed section 312, and the arc transition section 322 can be measured through experiments. Then, the lengths of the first, second, and third sections can be precisely designed (the wire diameters of the first, second, and third sections can be the same). This ensures that the materials of the first solder joint 301, the second solder joint 303, the annealed section 312, and the arc transition section 322 are the corresponding materials.
[0045] In some embodiments, the third conductive material and the first conductive material can be the same, so that the first segment and the second segment can be combined into one segment, thereby reducing the difficulty of wire bonding production.
[0046] It should be noted that this type of wire bonding can be used with corresponding wire bonding equipment. The wire bonding equipment can detect and precisely control the amount of wire used, so that the final bonded wire structure can match the segmented design mentioned above.
[0047] In summary, this embodiment provides a bonding wire structure and a packaging structure. The bonding wire structure includes a first solder joint portion 301, a second solder joint portion 303, and an intermediate connecting segment 302. The two ends of the intermediate connecting segment 302 are respectively connected to the first solder joint portion 301 and the second solder joint portion 303. The first solder joint portion 301 and the second solder joint portion 303 are made of a first conductive material, while at least a portion of the intermediate connecting segment 302 is made of a second conductive material. The first conductive material and the second conductive material are different. In this application, the material of at least a portion of the intermediate connecting segment 302 is different from the material of the first solder joint portion 301 and the second solder joint portion 303. Since the first solder joint portion 301 and the second solder joint portion 303 are closely related to the welding quality, high-priced, high-performance materials can be selected to ensure welding quality and meet the requirements of welding reliability. However, the intermediate connecting segment 302 has little impact on welding quality, so a lower-priced, slightly lower-performance material can be selected. This ensures welding quality while reducing costs and meeting product production requirements.
[0048] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple, and relevant parts can be referred to the method section.
[0049] It should also be noted that although preferred embodiments have been disclosed above, these embodiments are not intended to limit this application. Any person skilled in the art can make many possible variations and modifications to the technical solutions of this application, or modify them into equivalent embodiments, without departing from the scope of the technical solutions of this application. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of this application, without departing from the content of the technical solutions of this application, shall still fall within the scope of protection of the technical solutions of this application.
[0050] It should also be understood that, unless otherwise specified or indicated, the terms “first,” “second,” “third,” etc., in the specification are used only to distinguish the various components, elements, and steps in the specification, and not to indicate the logical or sequential relationships between the various components, elements, and steps.
[0051] Furthermore, it should be recognized that the terminology described herein is used only to describe particular embodiments and is not intended to limit the scope of this application. It must be noted that the singular forms “a” and “an” used herein and in the appended claims include plural bases unless the context clearly indicates otherwise. For example, a reference to “a step” or “an apparatus” means a reference to one or more steps or apparatuses, and may include secondary steps and secondary apparatuses. All conjunctions used should be understood in the broadest sense. Also, the word “or” should be understood to have the definition of logical “or” rather than logical “exclusive OR”, unless the context clearly indicates otherwise. Furthermore, implementations of the methods and / or devices in the embodiments of this application may include performing selected tasks manually, automatically, or in combination.
Claims
1. A bonding wire structure, characterized in that, It includes a first solder joint portion (301), a second solder joint portion (303), and an intermediate connecting section (302), wherein the two ends of the intermediate connecting section (302) are respectively connected to the first solder joint portion (301) and the second solder joint portion (303); The first solder joint portion (301) and the second solder joint portion (303) are made of a first conductive material, and at least a portion of the intermediate connecting section (302) is made of a second conductive material. The first conductive material is different from the second conductive material.
2. The bonding wire structure according to claim 1, characterized in that, The oxidation resistance of the first conductive material is greater than that of the second conductive material.
3. The bonding wire structure according to claim 1 or 2, characterized in that, The first solder joint portion (301) is a spherical solder joint, and the second solder joint portion (303) is a wedge-shaped solder joint.
4. The bonding wire structure according to claim 3, characterized in that, The intermediate connecting section (302) includes a line arc transition section (322) and an annealed section (312) connected to each other. The annealed section (312) connects to the first solder joint portion (301), and the line arc transition section (322) connects to the second solder joint portion (303). The material of the annealed section (312) is a third conductive material, and at least a portion of the material of the line arc transition section (322) is the second conductive material. The third conductive material is different from the second conductive material.
5. The bonding wire structure according to claim 4, characterized in that, The third conductive material has a greater antioxidant property than the second conductive material; and / or, the third conductive material is the same as the first conductive material.
6. The bonding wire structure according to claim 4, characterized in that, The length of the annealing section (312) is 30μm to 150μm.
7. The bonding wire structure according to claim 1, characterized in that, The ratio of the portion of the intermediate connecting segment (302) made of the second conductive material to the length of the intermediate connecting segment (302) is greater than or equal to 50%.
8. The bonding wire structure according to claim 1 or 2, characterized in that, The first conductive material is gold, and the second conductive material is at least one of gold alloy, silver, copper, iron, and aluminum.
9. The bonding wire structure according to claim 1 or 2, characterized in that, The first conductive material and the second conductive material are gold alloys, and the gold content in the first conductive material is greater than the gold content in the second conductive material.
10. A packaging structure, characterized in that, It includes at least one pair of solder pads, with a bonding wire structure as described in any one of claims 1 to 9 soldered between each pair of solder pads.