Wire bonding tool

Abstract

A wire bonding tool is provided. The wire bonding tool includes a body portion including a tip portion. The wire bonding tool also includes a first coating applied to the tip portion. The wire bonding tool also includes a second coating applied to the first coating.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of U.S. Provisional Application No. 63 / 336,033, filed April 28, 2022, the contents of which are incorporated herein by reference. Technical Field

[0003] This invention relates to wire bonding tools, and more particularly to wire bonding tools including a coating and a method of providing said wire bonding tool. Background Technology

[0004] In the handling and packaging of semiconductor devices and other electronic components, wire bonding remains the primary method for providing electrical interconnections between two locations within a package (e.g., between die pads on a semiconductor die and leads in a leadframe). More specifically, using a wire bonder (also known as a wire bonder), wire loops are formed between the respective locations to be electrically interconnected. The main methods for forming wire loops are ball bonding and wedge bonding (including strip bonding).

[0005] In the wire bonding industry, contamination at the tip of wire bonding tools (including wire adhesion) and surface wear at the tip limit the usable life of wire bonding tools.

[0006] U.S. Patent Nos. 6,729,527 (titled “BONDING TOOL WITH POLYMER COATING”) and 6,171,456 (titled “METHOD FOR MAKINGIMPOVED LONG LIFE BONDINGTOOLS”) relate to coatings for wire bonding tools, and the entire contents of them are incorporated herein by reference.

[0007] It will be expected that improved wire bonding tools will be provided, overcoming one or more of the shortcomings of conventional wire bonding tools. Utility Model Content

[0008] According to an exemplary embodiment of the present invention, a wire bonding tool is provided. The wire bonding tool includes a body portion, the body portion including a tip portion. The wire bonding tool further includes a first coating applied to the tip portion. The wire bonding tool further includes a second coating applied to the first coating.

[0009] According to an exemplary aspect of the invention, the wire bonding tool mentioned in the preceding paragraph may include any one or more of the following features: the body portion comprises at least one of ceramic, metal alloy, metal matrix composite, and ceramic matrix composite; the first coating is resistant to at least one of corrosion and abrasion; the first coating comprises at least one of metal, metal compound, and ceramic; the first coating comprises at least one of chromium, titanium, chromium carbide, chromium nitride, and titanium nitride; the first coating has a thickness of 0.5 to 10 micrometers; the first coating has a thickness of 0.5 to 2 micrometers; the second coating is resistant to at least one of adhesion and friction; the second coating is carbon-based; the second coating comprises at least one of diamond-like carbon, non-hydrogenated diamond-like carbon, tetragonal amorphous carbon, and carbon-based coating; the second coating has a thickness of 0.1 to 10 micrometers; and the second coating has a thickness of 0.3 to 5 micrometers.

[0010] According to another exemplary embodiment of the present invention, a method for providing a wire bonding tool is provided. The method includes the steps of: (a) providing a body portion of the wire bonding tool, the body portion including a tip portion; (b) applying a first coating to the tip portion; and (c) applying a second coating to the first coating.

[0011] According to an exemplary aspect of the invention, the method mentioned in the preceding paragraph may include any one or more of the following features: the body portion provided in step (a) comprises at least one of ceramic, metal alloy, metal matrix composite, and ceramic matrix composite; the first coating provided in step (b) is resistant to at least one of corrosion and wear; the first coating provided in step (b) comprises at least one of metal, metal compound, and ceramic; the first coating provided in step (b) comprises at least one of chromium, titanium, chromium carbide, chromium nitride, and titanium nitride; the first coating provided in step (b) has a thickness of 0.5 to 10 micrometers; the first coating provided in step (b) has a thickness of 0.5 to 2 micrometers; the second coating provided in step (c) is resistant to at least one of adhesion and friction; the second coating provided in step (c) is carbon-based; the second coating provided in step (c)... The method includes at least one of diamond-like carbon, non-hydrogenated diamond-like carbon, tetragonal amorphous carbon, and carbon-based coatings; the second coating provided in step (c) has a thickness of 0.1 to 10 micrometers; the second coating provided in step (c) has a thickness of 0.3 to 5 micrometers; the method further includes a step of cleaning the surface of the terminal portion before step (b) and a step of activating the surface of the terminal portion after the cleaning step but before step (b); the cleaning step includes degreasing the surface of the terminal portion; the cleaning step includes plasma cleaning the surface of the terminal portion; the method further includes a step of activating the surface of the terminal portion after step (b) but before step (c); step (b) includes applying a first coating using at least one of a cathode arc, a filtered cathode vacuum arc, and chemical vapor deposition; and step (c) includes applying a second coating using at least one of a cathode arc, a filtered cathode vacuum arc, and chemical vapor deposition. Attached Figure Description

[0012] The invention is best understood from the following detailed description when read in conjunction with the accompanying drawings. It is emphasized that, by convention, the various features in the drawings are not drawn to scale. Instead, for clarity, the dimensions of the various features have been arbitrarily enlarged or reduced. The drawings include the following figures:

[0013] Figure 1A-1C This is a partial cross-sectional side view used to illustrate different exemplary welding tools of the present invention;

[0014] Figure 2A-2C This is according to different exemplary embodiments of the present invention during the coating process. Figure 1A-1C A partial cross-sectional side view of the wire bonding tool;

[0015] Figures 3A-3C The coated wire according to different exemplary embodiments of the wire invention Figure 1A-1C A partial cross-sectional side view of the wire bonding tool;

[0016] Figure 4 This is in accordance with different exemplary embodiments of the present invention. Figures 3A-3C A detailed view of a portion of the wire bonding tool illustrated in the image; and

[0017] Figure 5 This is a flowchart illustrating a method for providing wire bonding tools according to different exemplary embodiments of the present invention. Detailed Implementation

[0018] As used herein, the term “wire bonding tool” is intended to refer to any of the various types of wire bonding tools, such as wedge bonding tools (e.g., thin wire wedges, thick wire wedges, etc.), ball bonding tools (e.g., capillary / cleaver tools), strip bonding tools, etc.

[0019] As used herein, "coating" refers to the material applied to the surface of a wire bonding tool. Although a second coating is "applied" to a first coating, this does not necessarily mean that the second coating is applied directly to the first coating. In other words, an intermediate coating or layer may separate the second coating from the first coating; therefore, the second coating may be applied indirectly to the first coating. Similarly, coatings (e.g., first coating, second coating, etc.) may be applied indirectly to the wire bonding tool. The "first" coating is not necessarily the innermost coating or layer for the wire bonding tool; furthermore, the "second" coating is not necessarily the outermost coating.

[0020] Now refer to the attached diagram, Figure 1A-1C The illustrations show different wire bonding tools. More specifically, Figure 1A The illustration shows a wedge-shaped welding tool including a "V"-shaped groove. Figure 1B The illustration shows a strip welding tool, and Figure 1C The illustration depicts a wire wedge welding tool. Of course, other types of wire welding tools are also considered within the scope of this invention. Figure 1A-1C The illustration shows the tip portion of different wire bonding tools. The tip portion is the part of the wire bonding tool that comes into contact with the workpiece during the wire bonding operation.

[0021] For details, please refer to the following: Figure 1A A wire bonding tool 100 is illustrated. The wire bonding tool 100 includes a body portion 100a, which includes a tip portion 100b at an end. The body portion 100a includes a surface 100a1. The tip portion 100b includes a portion of the surface 100a1 designated as surface 100b1. The tip portion 100b defines a V-groove configured to receive wire during the wire bonding operation.

[0022] Now for reference Figure 1BA wire bonding tool 102 (e.g., a strip bonding tool) is illustrated. The wire bonding tool 102 includes a body portion 102a, which includes a tip portion 102b at an end. The body portion 102a includes a surface 102a1. The tip portion 102b includes a portion of surface 102a1 designated as surface 102b1. The tip portion 102b includes a bonding surface 102c configured to contact the wire during the wire bonding operation.

[0023] Now for reference Figure 1C A wire bonding tool 104 is illustrated. The wire bonding tool 104 includes a body portion 104a, which includes a tip portion 104b at an end. The body portion 104a includes a surface 104a1. The tip portion 104b includes a portion of surface 104a1 designated as surface 104b1. The tip portion 104b includes a bonding surface 104c configured to contact the wire during the wire bonding operation.

[0024] Wire bonding tools 100, 102, and 104 can be described as “uncoated.” Each of the wire bonding tools 100, 102, and 104 can be cleaned (e.g., degreased or additionally cleaned as needed depending on the type of tool and the coating to be applied) before applying a coating. More specifically, at least the distal portion of each of these wire bonding tools can be cleaned (e.g., surface 100b1, surface 102b1, and bonding surface 102c). Of course, the entire surface of each of these wire bonding tools can also be cleaned. Furthermore, the surface of each of these wire bonding tools (e.g., at least at the corresponding distal portion) can be “activated” to make the surface more receptive to coating (e.g., see [link to relevant documentation]). Figure 5 Step 506). As those skilled in the art will understand, surface activation (e.g., surface activation of a metal wedge welding tool) alters the surface energy of the wire bonding tool, thus making the wire bonding tool more likely to attract coating particles.

[0025] Now for reference Figure 2A-2C Each of wire bonding tools 100, 102, and 104 has received a corresponding first coating, such that these tools are now labeled as wire bonding tools 100', 102', and 104'. Wire bonding tool 100' includes a first coating 106 applied to the tip portion 100b, wire bonding tool 102' includes a first coating 106 applied to the tip portion 102b, and wire bonding tool 104' includes a first coating 106 applied to the tip portion 104b. The corresponding first coating can be considered as an inner coating or inner layer applied to the corresponding surface of the tip portion of the wire bonding tool. Although Figure 2A-2C The illustration shows that the first coating 106 is applied only to the tip of the corresponding wire bonding tool; however, it is understood that any part of the surface of the wire bonding tool (including the entire surface) can be coated.

[0026] Now for reference Figures 3A-3C Each of the wire bonding tools 100, 102, and 104 has received the corresponding second coating (in Figure 2A-2C Following the first coating 106 shown, these tools are now labeled as wire bonding tools 100”, 102”, and 104”. Wire bonding tool 100” includes a second coating 108 applied to the tip portion 100b (on the first coating 106), wire bonding tool 102” includes a second coating 108 applied to the tip portion 102b (on the first coating 106), and wire bonding tool 104” includes a second coating 108 applied to the tip portion 104b (on the first coating 106). The corresponding second coating can be considered as an outer coating or outer layer of the first coating (or inner coating) applied to the tip portion of the corresponding wire bonding tool. Although Figures 3A-3C The illustration shows that the second coating 108 is applied only to the tip of the corresponding wire bonding tool, but it is understood that any part of the surface of the wire bonding tool (including the entire surface) can be coated.

[0027] Now for reference Figure 4 A portion of the wire bonding tool 100 (or wire bonding tool 102" or wire bonding tool 104") is illustrated to show the first coating 106 and the second coating 108 more clearly. Although Figure 4 The first coating 106 and the second coating 108 are illustrated as having approximately equal thicknesses, but the invention is not limited thereto. For example, in some embodiments of the invention, the first coating 106 may have a thickness of 0.5 to 10 micrometers; in other embodiments, the first coating 106 may have a thickness of 0.5 to 2 micrometers. For example, in some embodiments of the invention, the second coating 108 may have a thickness of 0.1 to 10 micrometers; in other embodiments, the second coating 108 may have a thickness of 0.3 to 5 micrometers. Of course, these ranges are exemplary in nature. The exact thickness of the first coating 106 or the second coating 108 will depend on the application and conditions associated with the specific welding operation.

[0028] Figure 5 This is a flowchart of different methods for providing welding tools. As those skilled in the art will understand, some steps included in the flowchart may be omitted; some other steps may be added; and the order of the steps may be changed from the order shown in the illustration—all of these are within the scope of this invention.

[0029] At step 502, the body portion of the wire bonding tool is provided, the body portion including a terminal portion (e.g., see...). Figure 1A-1CThe body portions 100a, 102a, and 104a include the corresponding terminal portions. For example, the body portions provided in step 502 may include ceramics, metal alloys, metal matrix composites, or ceramic matrix composites (or be made entirely of ceramics, metal alloys, metal matrix composites, or ceramic matrix composites). In optional step 504, prior to step 508, the surface of the terminal portion of the wire bonding tool is cleaned. The cleaning step (i.e., step 504) may include degreasing the surface of the terminal portion. The cleaning step (i.e., step 504) may include plasma cleaning of the surface of the terminal portion. In optional step 506, after the cleaning step (i.e., step 504) but prior to step 508, the surface of the terminal portion is activated. This "activation" refers to increasing the surface energy of the material, making it more receptive to another material (i.e., via the formation of atomic bonds). This activation can be achieved by applying energy (e.g., plasma) to the surface to be activated.

[0030] At step 508, the first coating is applied to the distal portion (e.g., see...). Figure 2A-2C The coating provided at step 508 may be resistant to corrosion or abrasion. For example, the coating provided at step 508 (i.e., the first coating) may include metals, metal compounds, and ceramics (or be made entirely of metals, metal compounds, and ceramics). For example, the coating provided at step 508 may include chromium, titanium, chromium carbide, chromium nitride, and titanium nitride (or be made entirely of chromium, titanium, chromium carbide, chromium nitride, and titanium nitride). For example, the coating provided at step 508 may have a thickness of 0.5 to 10 micrometers; in another example, the coating may have a thickness of 0.5 to 2 micrometers. The coating provided at step 508 may be applied, for example, using cathodic arc coating technology, using filtered cathodic vacuum arc coating technology, or using chemical vapor deposition. In an optional step 510, the surface of the distal portion is activated after step 508 but before step 512.

[0031] At step 512, the second coating is applied to the first coating (e.g., see...). Figures 3A-3C The coating provided at step 512 (i.e., the second coating) may be resistant to adhesion or friction. The coating provided at step 512 may be carbon-based. For example, the coating provided at step 512 may include diamond-like carbon, non-hydrogenated diamond-like carbon, tetragonal amorphous carbon, and carbon-based coatings (or may be made entirely of diamond-like carbon, non-hydrogenated diamond-like carbon, tetragonal amorphous carbon, and carbon-based coatings). For example, the coating provided at step 512 may have a thickness of 0.1 to 10 micrometers; in another example, the coating may have a thickness of 0.3 to 5 micrometers. The coating provided at step 512 may be applied, for example, using cathodic arc coating technology, using filtered cathodic vacuum arc coating technology, or using chemical vapor deposition.

[0032] Although the invention has been illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications in detail may be made within the scope of the claims and their equivalents, and without departing from the invention.

Claims

1. A wire bonding tool, characterized in that... include: The body portion includes a terminal portion; A first coating is applied to a distal portion, wherein the first coating is applied to an activation surface of the distal portion, the activation surface having a changed surface energy that makes it more likely to attract coating particles of the first coating. as well as A second coating applied to the first coating.

2. The wire bonding tool according to claim 1, characterized in that, The body part is made of ceramic, metal alloy, metal matrix composite or ceramic matrix composite.

3. The wire bonding tool according to claim 1, characterized in that, The first coating is resistant to at least one of corrosion and abrasion.

4. The wire bonding tool according to claim 1, characterized in that, The first coating is made of metal, metal compound, or ceramic.

5. The wire bonding tool according to claim 1, characterized in that, The first coating is made of chromium, titanium, chromium carbide, chromium nitride, or titanium nitride.

6. The wire bonding tool according to claim 1, characterized in that, The first coating has a thickness of 0.5 to 10 micrometers.

7. The wire bonding tool according to claim 1, characterized in that, The first coating has a thickness of 0.5 to 2 micrometers.

8. The wire bonding tool according to claim 1, characterized in that, The second coating is resistant to at least one of adhesion and friction.

9. The wire bonding tool according to claim 1, characterized in that, The second coating is carbon-based.

10. The wire bonding tool according to claim 1, characterized in that, The second coating is made of diamond-like carbon, non-hydrogenated diamond-like carbon, tetragonal amorphous carbon, or carbon-based coating.

11. The wire bonding tool according to claim 1, characterized in that, The second coating has a thickness of 0.1 to 10 micrometers.

12. The wire bonding tool according to claim 1, characterized in that, The second coating has a thickness of 0.3 to 5 micrometers.

13. The wire bonding tool according to claim 1, characterized in that, The body portion is made of ceramic, the first coating is made of chromium, and the second coating is made of carbon-based coating.

14. The wire bonding tool according to claim 13, characterized in that, The body portion is made of ceramic matrix composite material.

15. The wire bonding tool according to claim 13, characterized in that, The first coating is made of chromium nitride.

16. The wire bonding tool according to claim 13, characterized in that, The body portion is made of a ceramic matrix composite material, and the first coating is made of chromium nitride.

17. The wire bonding tool according to claim 13, characterized in that, The second coating is made of diamond-like carbon.

18. The wire bonding tool according to claim 13, characterized in that, The second coating is made of tetragonal amorphous carbon.

19. The wire bonding tool according to claim 13, characterized in that, The body portion is made of a ceramic matrix composite material, and the second coating is made of diamond-like carbon.

20. The wire bonding tool according to claim 13, characterized in that, The body portion is made of ceramic matrix composite material, and the second coating is made of tetragonal amorphous carbon.

21. The wire bonding tool according to claim 13, characterized in that, The first coating is made of chromium nitride, and the second coating is made of diamond-like carbon.

22. The wire bonding tool according to claim 13, characterized in that, The first coating is made of chromium nitride, and the second coating is made of tetragonal amorphous carbon.

23. The wire bonding tool according to claim 13, characterized in that, The body portion is made of a ceramic matrix composite material, the first coating is made of chromium nitride, and the second coating is made of diamond-like carbon.

24. The wire bonding tool according to claim 13, characterized in that, The body portion is made of a ceramic matrix composite material, the first coating is made of chromium nitride, and the second coating is made of tetragonal amorphous carbon.

25. The wire bonding tool according to claim 1, characterized in that, The body portion is made of ceramic or ceramic matrix composite material.

26. The wire bonding tool according to claim 25, characterized in that, The first coating is made of chromium, chromium carbide or chromium nitride.

27. The wire bonding tool according to claim 25 or 26, characterized in that, The second coating is made of diamond-like carbon, tetragonal amorphous carbon, or a carbon-based coating.

28. The wire bonding tool according to claim 25, characterized in that, The first coating is made of chromium or chromium nitride.

29. The wire bonding tool according to claim 1, 25, or 28, characterized in that, The second coating is made of diamond-like carbon, tetragonal amorphous carbon, or a carbon-based coating.

30. The wire bonding tool according to claim 1, 25, or 28, characterized in that, The second coating is made of diamond-like carbon or tetragonal amorphous carbon.

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