Bonding wedge

Abstract

The utility model provides a kind of bonding wedge, the bonding wedge includes the shank and the head being connected, the head is equipped with the oblique lead-through hole passing through, the end of the head is provided with wire slot and bonding part, the oblique lead-through hole and the bonding part are respectively arranged in the two sides of the wire slot;The working surface of the bonding part is provided with the groove passing through;Lead wire can be sequentially inserted into the oblique lead-through hole, the wire slot and the groove, and extend from the groove;At least one groove wall on the two sides of the groove is provided with the notch passing through, and the notch is communicated with the groove.This bonding wedge sets up notch on the groove wall of bonding part, can discharge the metal scrap produced after lead wire and wedge inner wall friction from notch, effectively slows down the accumulation of metal scrap on wedge inner wall, greatly improves the service life of wedge.

Description

Technical Field

[0001] This utility model relates to the field of integrated circuit packaging technology, and in particular to a bonding cutter. Background Technology

[0002] Currently, in integrated circuit manufacturing processes, bonding is the common method for connecting the die (diced wafer) to the peripheral framework. Bonding is also widely used in the manufacturing of other electronic devices due to its speed and stability. Bonding is divided into ball bonding and wedge bonding, with wedge bonding being increasingly adopted due to its smaller lead footprint.

[0003] The bonding tooling used in wedge bonding is called a wedge. The evolution of wedges has progressed from planar wedges to C-shaped wedges, and then to U-groove wedges or V-groove wedges. This evolution increases the contact area between the wedge and the lead, achieving higher efficiency and shorter bonding times, while reducing damage to the lead's feet. However, with the wider adoption of wedge bonding, the drawback of wedge lifespan has become increasingly apparent. In existing technologies, the bottom of the wedge is the bonding surface. During wedge bonding, friction exists between the inner wall of the wedge groove and the lead. This friction causes the lead to rub back and forth on the pad, forming a weld. During the bonding process, ineffective friction also occurs between the wedge and the lead—relative sliding between the wedge groove and the lead. This exacerbates the generation of lead metal shavings, which accumulate on the inner wall of the wedge groove, forming bulges. This not only degrades the weld quality but also renders the wedge unusable, thus reducing its lifespan.

[0004] Because cleavers are expensive, and for the reasons mentioned above, they often need to be replaced after only tens of thousands to two or three hundred thousand uses. To increase the lifespan of cleavers, more wear-resistant materials can be used during manufacturing, or a wear-resistant coating can be applied to the inner wall of the cleaver. However, both of these methods significantly increase the price of the cleaver while increasing its lifespan. Utility Model Content

[0005] To address the technical problems existing in the prior art, the purpose of this utility model is to provide a bonding wedge. This bonding wedge has a notch in the groove wall of the bonding part, which can effectively discharge the metal shavings generated after the lead wire rubs against the inner wall of the wedge from the notch, effectively reducing the accumulation of metal shavings on the inner wall of the wedge and greatly improving the service life of the wedge.

[0006] To achieve the above objectives, this utility model provides a bonding splitting tool, which includes a connected handle and a cutting head. The cutting head has a through-hole for oblique lead wires, and the end of the cutting head has a lead wire groove and a bonding part. The oblique lead wire groove and the bonding part are respectively located on both sides of the lead wire groove. A through groove is provided on the working surface of the bonding part. A lead wire can sequentially extend into the oblique lead wire groove, the lead wire groove, and the groove, and extend out of the groove. At least one through notch is provided on the groove wall on both sides of the groove, and the notch communicates with the groove.

[0007] Optionally, at least one notch is provided on both sides of the trench wall.

[0008] Optionally, a notch is provided on each of the two sides of the trench wall, and the two notches on the two sides of the trench wall are symmetrically arranged in the extension direction of the trench.

[0009] Optionally, multiple notches are provided on both sides of the trench wall, and the multiple notches on both sides of the trench wall are symmetrically or staggered in the extension direction of the trench.

[0010] Optionally, the notch has a sidewall perpendicular to the length direction of the groove wall.

[0011] Optionally, the notch may be rectangular, square, or arched in shape in a cross-section perpendicular to the width of the groove wall.

[0012] Optionally, the notch is located at the midpoint of the groove wall along its own length.

[0013] Optionally, the bonding portion has chamfers at both ends in its own length direction, and the notch is smaller than one-third of the groove wall's size in its own length direction.

[0014] Optionally, the depth of the notch in the direction perpendicular to the length of the groove wall is one-half of the deformation after the lead wire is welded.

[0015] Optionally, the groove may be U-shaped or V-shaped in cross-section perpendicular to the length of the groove wall.

[0016] This invention provides a bonding wedge with a notch in the groove wall of the bonding part. This notch effectively discharges metal shavings generated after the lead wire rubs against the inner wall of the wedge, preventing the accumulation of metal shavings in the groove of the wedge and significantly delaying the formation of metal shaving bulges inside the wedge. This significantly improves the service life of the wedge bonding wedge without significantly increasing the price of the wedge, while also reducing the quality risks after lead wire bonding.

[0017] Furthermore, during the solder joint formation process, the lead wire deforms and forms a protrusion corresponding to the notch. The protrusion on the lead wire is located within the notch of the wedge, which limits the relative position between the lead wire and the wedge, allowing the wedge and the lead wire to move forward and backward synchronously during friction welding. This eliminates ineffective friction between the wedge and the lead. With this structure, there will be no significant relative slippage between the wedge and the lead wire, effectively eliminating the generation of metal chips and further improving the service life of the wedge. Attached Figure Description

[0018] Figure 1 This is a partial axial cross-sectional view of the cutter head in a preferred embodiment of the present invention;

[0019] Figure 2 for Figure 1 A magnified view of a portion of the image;

[0020] Figure 3 This is a bottom view of the cutter head in a preferred embodiment of the present invention;

[0021] Figure 4 This is a front view of the cutter head in a preferred embodiment of the present invention;

[0022] Figure 5a This is a schematic diagram illustrating the use of a cleaver in existing technologies.

[0023] Figure 5b This is a schematic diagram illustrating the use of the cleaver in a preferred embodiment of the present invention.

[0024] The reference numerals in the attached figures are explained as follows:

[0025] Cutting head 1; oblique lead wire through hole 11; wire outlet groove 12; bonding part 13; groove 14; groove wall 141; notch 15; side wall 151; protrusion 2. Detailed Implementation

[0026] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer from the following description. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the present invention.

[0027] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0028] In this application, unless otherwise expressly stated, the use of singular terms should also include plural meanings. In this application, unless otherwise stated, the use of "or" means "and / or," and the use of other forms of expression belonging to "including" and such as "comprising" and "containing" is not restrictive. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise expressly and specifically defined.

[0029] The bonding cleaver proposed in this utility model will be described in detail below with reference to the accompanying drawings and preferred embodiments. Unless otherwise specified, the following embodiments and features can complement or combine with each other.

[0030] Figure 1 This is a partial axial cross-sectional view of the cutter head in a preferred embodiment of the present invention. Figure 2 for Figure 1 A magnified view of a portion of the image. Figure 3 This is a bottom view of the cutter head in a preferred embodiment of the present invention. Figure 4 This is a front view of the cutter head in a preferred embodiment of the present invention.

[0031] Figure 5a This is a schematic diagram illustrating the use of a cleaver in existing technologies. Figure 5b This is a schematic diagram illustrating the use of the cleaver in a preferred embodiment of the present invention.

[0032] like Figures 1-4 As shown, this utility model provides a bonding cleaver, which includes a connected shank (not shown) and a cleaver head 1. The cleaver head 1 has a wedge-shaped structure, and a through-hole 11 for inclined wire guide is provided inside the cleaver head 1. The end of the inclined wire guide 11 away from the shank is flared, making it easier to feed the wire (aluminum wire or copper wire). The end of the cleaver head 1 is provided with a wire outlet groove 12 and a bonding part 13, and the inclined wire guide 11 and the bonding part 13 are respectively provided on both sides of the wire outlet groove 12.

[0033] Furthermore, a through groove 14 is provided on the working surface of the bonding part 13 (i.e., the welding surface of the wedge), allowing the lead wire to sequentially extend into the inclined lead wire through hole 11, the wire exit groove 12, and the groove 14, and to extend out from the groove 14. At least one groove wall 141 on both sides of the groove 14 is provided with a through notch 15, which communicates with the groove 14 and allows friction debris from the lead wire and the wedge to be discharged.

[0034] This application provides a bonding wedge with a notch 15 on the groove wall 141 of the bonding portion 13. This notch 15 can effectively discharge metal shavings generated by the friction between the lead wire and the inner wall of the wedge through the notch 15, avoiding the accumulation of metal shavings in the groove 14 of the wedge and significantly delaying the formation of metal shaving bulges in the wedge. This can significantly improve the service life of the wedge bonding wedge without significantly increasing the price of the wedge, while also reducing the quality risk after lead wire bonding.

[0035] Reference Figure 5a and Figure 5b and combined Figure 1 and Figure 2 During the solder joint formation process, the lead wire deforms to form a protrusion 2 corresponding to the notch 15. The protrusion 2 on the lead wire is located within the notch 15 of the wedge, which limits the relative position between the lead wire and the wedge, allowing them to move forward and backward synchronously during friction welding. This eliminates ineffective friction between the wedge and the lead. With this structure, there will be no significant relative slippage between the wedge and the lead wire, effectively eliminating metal shavings and further improving the wedge's service life. In practical applications, adding a notch 15 to the groove wall 141 of the wedge can increase its service life from 100,000 to 200,000 bonding cycles to the million-cycle level.

[0036] This application does not limit the shape of the groove 14. The shape of the groove 14 in the cross section perpendicular to the length direction of the groove wall 141 can be set as U-shaped or V-shaped, that is, the groove 14 can be set as a U-shaped groove or a V-shaped groove.

[0037] This application does not limit the shape and size of the notch 15. The notch 15 can be designed in any shape and size as needed, as long as it is convenient to remove the metal shavings generated by the friction between the lead wire and the chopping tool.

[0038] Reference Figures 1-4 As shown, in a preferred embodiment, at least one notch 15 is provided on each of the two side walls 141 of the groove 14. For example, one, two, or three notches 15 can be provided on each of the two side walls 141 of the groove 14. Notches 15 for metal shavings to be discharged are provided on both sides of the bonding part 13 of the chopping blade, which can effectively prevent the accumulation of metal shavings and further improve the service life of the chopping blade.

[0039] As another preferred embodiment, at least one notch 15 may be provided only on one side wall 141 of the groove 14. For example, one, two or three notches 15 may be provided on one side wall 141 of the groove 14.

[0040] Refer to 1 and Figure 2 As shown in an illustrative embodiment, a notch 15 is provided on each of the two side walls 141 of the groove 14. The two notches 15 on the two side walls 141 are symmetrically arranged in the extension direction of the groove 14. At this time, the two notches 15 are connected in the width direction of the groove wall 141 (i.e., perpendicular to the extension direction of the groove 14), which is conducive to the discharge of metal shavings.

[0041] In another illustrative embodiment, a notch 15 is provided on each of the two side walls 141 of the trench 14, and the two notches 15 on the two side walls 141 are staggered in the extension direction of the trench 14 (i.e., asymmetrical).

[0042] In another illustrative embodiment, multiple notches 15 are provided on both sides of the trench 14. The multiple notches 15 on both sides of the trench 141 are symmetrically or staggered in the extension direction of the trench 14 to improve the discharge effect of metal scraps.

[0043] Reference Figure 1 and Figure 2 The notch 15 has a sidewall 151 perpendicular to the length direction of the groove wall 141, which is the extension direction of the groove 14. Preferably, the shape of the notch 15 in the cross-section perpendicular to the width direction of the groove wall 141 is rectangular, square, or arched. In this case, the intersection of the notch 15 and the working surface of the chopping tool is at a right angle, without the design of bevels and chamfers. This facilitates the vertical downward pressing and vertical lifting of the chopping tool and effectively reduces costs.

[0044] Continue to refer to Figures 1-4 In a preferred embodiment, the notch 15 is located at the midpoint of the groove wall 141 along its length. This configuration allows debris from both ends of the cutting surface to be quickly discharged through the notch 15. Of course, in other embodiments, the notch 15 can be positioned at any location along the length of the groove wall 141 as needed.

[0045] It should be noted that, in actual setup, depending on the specific product and application of the chopping cutter, the notch 15 on the cutter head 1 can preferably be positioned near the location where the chopping debris accumulates. In a specific application case, the location of debris accumulation in the groove 14 can be observed and determined by placing a used chopping cutter of the same type under a microscope.

[0046] Reference Figure 1 and Figure 2As shown, the bonding part 13 of the chopper has chamfers (unlabeled) at both ends in its own length direction. The dimension L1 of the notch 15 in the length direction of the groove wall 141 (i.e. the length of the notch 15) is less than one-third of the dimension L2 of the groove wall 141 in its own length direction (i.e. the length of the actual working surface of the chopper), that is, L1≤1 / 3L2. With this setting, the ineffective friction between the lead wire and the chopper can be reduced or even eliminated while keeping the lead wire welding shape basically unchanged, thus ensuring the welding effect of the lead wire.

[0047] This patent uses a U-shaped or V-shaped groove wedge adapted for a 50µm lead wire as an example for illustration. The bonding portion 13 of the wedge for the 50µm lead wire adapter is approximately 89µm in length. Since the bonding portion 13 has chamfers at both the beginning and end, the actual working surface length of the wedge for the 50µm lead wire adapter is approximately 3 / 5 of the length of the bonding portion 13 (i.e., 54µm). The dimension L1 of the notch 15 in the length direction of the groove wall 141 does not exceed 1 / 3 of the actual working surface length L2 of the wedge. Therefore, when the actual working surface length of the wedge is 54µm, the dimension L1 of the notch 15 in the length direction of the groove wall 141 is less than 18µm, preferably 15µm to 18µm.

[0048] Furthermore, the depth range H1 of the notch 15 in the length direction perpendicular to the groove wall 141 is half of the deformation after the lead wire welding. This allows for an increase in the life of the cutting tool with only a small improvement in the cutting tool itself. The deformation after lead wire welding refers to the difference between the diameter of the lead wire and its height after welding, i.e., the reduction in height after welding.

[0049] For example, the deformation after soldering a 50µm lead is 16µm to 25µm. Since the depth range H1 of the notch 15 is half of the deformation after soldering, it is preferable to set the depth range H1 of the notch 15 to 8µm to 13µm.

[0050] It should be explained that the length and depth range of the notch 15 for other sizes of U-groove wedges or V-groove wedges only need to be enlarged and reduced proportionally according to the length and depth range of the wedge notch 15 adapted to the 50um lead wire.

[0051] Specifically, the dimension of the notch 15 along the length of the groove wall 141 depends on the length of the actual working surface of the cutting tool. The smaller the length of the actual working surface, the smaller the dimension of the notch 15 along the length of the groove wall 141; the larger the length of the actual working surface, the larger the dimension of the notch 15 along the length of the groove wall 141. The depth range of the cutting tool notch 15 can preferably be set to half of the deformation after lead wire welding, and the length of the cutting tool notch 15 is preferably no more than 1 / 3 of the length of the actual working surface of the cutting tool.

[0052] In specific application cases, when the cleaver is operating at different frequencies, with different bonding parameters, and is adapted to lead wires of different materials, the length and depth range of the cleaver notch 15 can be determined by referring to the above recommended dimensions and combining experimental verification results.

[0053] It should be understood that the improvement of this application is to provide a notch 15 in the groove wall 141 of the bonding portion 13 of the cleaver, which facilitates the discharge of metal chips and enables the cleaver and the lead wire to move synchronously. Therefore, for cleavers of different types, sizes and suitable for different lead wire materials, as long as a notch 15 is provided in the groove wall 141 of the bonding portion 13, they should all be included within the protection scope of this application.

[0054] In summary, this utility model provides a bonding wedge with a notch 15 on the groove wall 141 of the bonding portion 13. This notch 15 effectively discharges metal shavings generated after the lead wire rubs against the inner wall of the wedge, preventing the accumulation of metal shavings in the groove 14 of the wedge and significantly delaying the formation of metal shaving bulges inside the wedge. Thus, the service life of the wedge bonding wedge can be significantly improved without significantly increasing the price of the wedge, while also reducing the quality risks after lead wire bonding.

[0055] Reference Figure 5a and Figure 5b and combined Figure 1 and Figure 2 During the solder joint formation process, the lead wire deforms and forms a protrusion 2 corresponding to the notch 15. The protrusion 2 on the lead wire is located within the notch 15 of the wedge. This limits the relative position between the lead wire and the wedge, allowing the wedge and the lead wire to move forward and backward synchronously during friction welding, thereby eliminating ineffective friction between the wedge and the lead. With this structure, there will be no large relative slippage between the wedge and the lead wire, effectively eliminating the generation of metal chips and further improving the service life of the wedge.

[0056] The above description is only a description of the preferred embodiment of the present utility model and is not intended to limit the scope of the present utility model in any way. Any changes or modifications made by those skilled in the art based on the above disclosure shall fall within the protection scope of the present utility model.

Claims

1. A bonding cleaver, characterized in that, The bonding cutter includes a connected handle and a cutting head. The cutting head has a through-hole for the inclined lead wire, and the end of the cutting head has a lead wire groove and a bonding part. The inclined lead wire groove and the bonding part are respectively located on both sides of the lead wire groove. A through groove is provided on the working surface of the bonding part. The lead wire can sequentially extend into the inclined lead wire groove, the lead wire groove, and the groove, and extend out of the groove. At least one through notch is provided on the groove wall on both sides of the groove, and the notch communicates with the groove.

2. The bonding cleaver as described in claim 1, characterized in that, At least one notch is provided on both sides of the trench wall.

3. The bonding cleaver as described in claim 1, characterized in that, A notch is provided on each of the two sides of the trench wall, and the two notches on the two sides of the trench wall are symmetrically arranged in the extension direction of the trench.

4. The bonding cleaver as described in claim 1, characterized in that, Multiple notches are provided on both sides of the trench wall, and the multiple notches on both sides of the trench wall are symmetrically or staggered in the extension direction of the trench.

5. The bonding cleaver as described in any one of claims 1 to 4, characterized in that, The notch has a sidewall perpendicular to the length of the groove wall.

6. The bonding cleaver as described in claim 5, characterized in that, The notch has a rectangular, square, or arched shape in its cross-section perpendicular to the width of the groove wall.

7. The bonding cleaver as described in any one of claims 1 to 4, characterized in that, The notch is located at the midpoint of the groove wall along its own length.

8. The bonding cleaver as described in any one of claims 1 to 4, characterized in that, The bonding portion has chamfers at both ends along its length, and the notch is smaller than one-third of the groove wall's length along its length.

9. The bonding cleaver as described in any one of claims 1 to 4, characterized in that, The depth of the notch in the direction perpendicular to the length of the groove wall is half of the deformation after the lead wire is welded.

10. The bonding cleaver as described in any one of claims 1 to 4, characterized in that, The groove has a U-shaped or V-shaped cross-section perpendicular to the length of the groove wall.

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