Bonding structure and bonding method suitable for ultrasonic welding

Abstract

The invention discloses a bonding structure suitable for ultrasonic welding and a bonding method, the bonding structure comprises a bonding wire and a target device, the target device further comprises a bonding interface, a plurality of protrusions on the bonding interface are arranged in an array mode, a preset distance is kept between every two adjacent columns of protrusions, and the bonding interface is connected with the bonding wire. The spacing is used for matching the bonding wire with a predetermined length and diameter and enabling the bonding wire with the predetermined length and diameter to be in contact with the plurality of bulges in two adjacent rows, and a plurality of continuous bonding connection points are formed in the predetermined length direction of the bonding wire. According to the invention, by arranging the array bulges on the bonding interface, the bulges can be matched with the bonding wires with preset lengths and diameters, and the bulges can provide more surface areas, so that the welding strength is improved. In addition, bubbles and defects in the welding process can be reduced through the protrusions.

Description

Technical Field

[0001] The invention relates to the field of ultrasonic micro-motion welding, and in particular to a bonding structure and a bonding method suitable for ultrasonic welding. Background Art

[0002] In the microelectronics industry, wire bonding is a process that uses thin metal wires (bonding wires) to weld metal wires (bonding wires) tightly to substrate pads using heat, pressure, and ultrasonic energy to achieve electrical interconnection between chips and substrates and information exchange between chips. Under ideal control conditions, electron sharing or atomic diffusion occurs between the bonding wires and the substrate to form welding points. There are three commonly used wire bonding methods, namely, thermocompression bonding, ultrasonic bonding, and thermoacoustic bonding.

[0003] The bonding interface refers to a method of forming a connection joint at the interface between the bonding wire and the pad. During the bonding process, the bonding equipment forms a connection joint by applying different energies such as pressure, mechanical vibration, electrical energy or thermal energy to the interface between the bonding wire and the pad. Under ideal circumstances, a covalent bond will be formed at the bonding interface, thereby achieving welding.

[0004] In the prior art ultrasonic micro-motion welding, unsatisfactory welding effects still occur from time to time. The reason is that there are various defects in the bonding interface, which affects the final welding effect. In the present invention, a new bonding structure is constructed, which can significantly improve the welding effect of ultrasonic micro-motion welding. Summary of the invention

[0005] The purpose of the present invention is to overcome the above-mentioned deficiencies in the prior art and to provide a bonding structure and a bonding method suitable for ultrasonic welding.

[0006] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention is:

[0007] On the one hand, the present invention provides a bonding structure suitable for ultrasonic welding, including a bonding wire and a target device, wherein the target device also includes a bonding interface, and a plurality of protrusions are arranged on the bonding interface. A predetermined spacing is maintained between the protrusions, and the spacing is used to match the bonding wire and make the bonding wire contact with the protrusion to form a bonding connection point.

[0008] The plurality of protrusions on the bonding interface are arranged in an array, and a predetermined spacing is maintained between two adjacent columns of protrusions. The spacing is used to match the bonding wire of a predetermined length and diameter and to make the bonding wire of the predetermined length and diameter contact with the plurality of protrusions in two adjacent columns, thereby forming a plurality of continuous bonding connection points in the predetermined length direction of the bonding wire.

[0009] The heights of the plurality of protrusions on the bonding interface are proportional to the diameter of the bonding wire.

[0010] The protrusion is in a conical shape, and a plurality of nanoparticles are arranged on the surface of the protrusion.

[0011] The diameter dimension of the bonding wire and the height dimension of the protrusion include the following matching:

[0012] The diameter of the bonding wire is 0.5 mm, and the height of the protrusion is 0.05 mm to 0.1 mm;

[0013] Alternatively, the diameter of the bonding wire is 1 mm, and the height of the protrusion is 0.1 mm to 0.2 mm.

[0014] The present invention also provides a bonding method suitable for ultrasonic welding, comprising the following steps:

[0015] 6.1 Prepare a bonding wire and a target device;

[0016] 6.2 providing a bonding interface including a plurality of protrusions on the target device;

[0017] 6.3 Maintain a predetermined distance between the protrusions, wherein the distance is used to match the bonding wire, so that the bonding wire contacts the protrusion to form a bonding connection point.

[0018] The plurality of protrusions on the bonding interface are arranged in an array, and a predetermined spacing is maintained between two adjacent columns of protrusions. The spacing is used to match the bonding wire of a predetermined length and diameter and to make the bonding wire of the predetermined length and diameter contact with the plurality of protrusions in two adjacent columns, thereby forming a plurality of continuous bonding connection points in the predetermined length direction of the bonding wire.

[0019] The heights of the plurality of protrusions on the bonding interface are proportional to the diameter of the bonding wire.

[0020] The shape of the protrusion is set to be a cone shape, and a plurality of nanoparticles are set on the surface of the protrusion.

[0021] Beneficial effects of the present invention:

[0022] The present invention provides an array of protrusions at the bonding interface so that the protrusions can fit with the bonding wire of predetermined length and diameter, and the protrusions can provide more surface area, thereby increasing the welding strength. In addition, the protrusions can also reduce bubbles and defects during the welding process. In addition, in ultrasonic welding, the conical protrusions of the present invention are easier to achieve covalent bonds than spherical protrusions, because the conical protrusions can provide more surface area, thereby increasing the welding strength. In addition, the conical protrusions can also reduce bubbles and defects during the welding process. In addition, the conical protrusions described in the present invention are also provided with a number of nanoparticles, and these microscopic particles can more effectively increase the area of ​​contact with the bonding wire, thereby improving the quality of ultrasonic welding. Description of the drawings:

[0023] Figure 1 Schematic diagram of the bonding structure of the present invention.

[0024] Figure 2 It is an enlarged view of the bonding interface described in the present invention. DETAILED DESCRIPTION

[0025] The present invention is further described in detail below in conjunction with specific embodiments. However, it should not be understood that the scope of the above subject matter of the present invention is limited to the following embodiments, and all technologies realized based on the content of the present invention belong to the scope of the present invention.

[0026] See also Figure 1 On the one hand, the present invention provides a bonding structure 100 suitable for ultrasonic welding, including a bonding wire 10 and a target device 20, wherein the target device 20 also includes a bonding interface 30, and a plurality of protrusions 31 are arranged on the bonding interface 30, and a predetermined spacing is maintained between the protrusions 31, and the spacing is used to match the bonding wire 10 and make the bonding wire 10 contact with the protrusions 31 to form a bonding connection point.

[0027] See also Figure 1 and Figure 2 The plurality of protrusions 31 on the bonding interface 30 are arranged in an array, and a predetermined spacing is maintained between two adjacent rows of protrusions 31 ( Figure 1 The protrusions 31 are arranged closely, but the protrusions between two adjacent columns are kept at a distance. The column mentioned here refers to the protrusion column parallel to the length of the bonding wire 10. The distance is used to match the bonding wire of a predetermined length and diameter and make the bonding wire 10 of the predetermined length and diameter contact with a number of the protrusions 31 of two adjacent columns (the predetermined length here refers to Figure 1 The length of the portion of the bonding wire 10 located in the target device 20 region that matches the protrusion 31 is determined to form a plurality of continuous bonding connection points in the predetermined length direction of the bonding wire 10, such as Figure 2 For the bonding connection points a, b and c in the figure, by the same token, the contact points symmetrical to the bonding connection points a, b and c along the bonding line 10 also belong to the bonding connection points.

[0028] As an embodiment, the height of the plurality of protrusions 31 on the bonding interface 30 is proportional to the diameter of the bonding wire 10. The height of the protrusion 31 here refers to its height relative to the plane in the bonding interface 30 area. As an embodiment, the diameter of the bonding wire 10 and the height of the protrusion 31 may include the following matching: the diameter of the bonding wire 10 is 0.5 mm, and the height of the protrusion 31 is 0.05 mm to 0.1 mm; or, the diameter of the bonding wire 10 is 1 mm, and the height of the protrusion 31 is 0.1 mm to 0.2 mm.

[0029] As an embodiment, the protrusion 31 is in a conical shape, and a plurality of nanoparticles are disposed on the surface of the protrusion 31 .

[0030] On the other hand, the present invention also provides a bonding method suitable for ultrasonic welding, comprising the following steps:

[0031] 6.1 Prepare a bonding wire and a target device;

[0032] 6.2 providing a bonding interface including a plurality of protrusions on the target device;

[0033] 6.3 Maintain a predetermined distance between the protrusions, wherein the distance is used to match the bonding wire, so that the bonding wire contacts the protrusion to form a bonding connection point.

[0034] As an embodiment, the plurality of protrusions on the bonding interface are arranged in an array, and a predetermined spacing is maintained between the two adjacent columns of protrusions, and the spacing is used to match the bonding wire of a predetermined length and diameter and make the bonding wire of the predetermined length and diameter contact with the plurality of protrusions in two adjacent columns, so as to form a plurality of continuous bonding connection points in the predetermined length direction of the bonding wire. The height of the plurality of protrusions on the bonding interface is proportional to the diameter of the bonding wire. The shape of the protrusion is set to be a cone shape, and a plurality of nanoparticles are arranged on the surface of the protrusion.

[0035] The specific embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments. Those skilled in the art may make various modifications or alterations without departing from the spirit and scope of the claims of the present application.

Claims

1. A bonding structure suitable for ultrasonic welding, comprising a bonding wire and a target device, characterized in that: The target device also includes a bonding interface, on which a plurality of protrusions are arranged, and a predetermined interval is maintained between the protrusions, and the interval is used to match the bonding wire and make the bonding wire contact the protrusion to form a bonding connection point.

2. The bonding structure according to claim 1, characterized in that: The plurality of protrusions on the bonding interface are arranged in an array, and a predetermined spacing is maintained between two adjacent columns of protrusions. The spacing is used to match the bonding wire of a predetermined length and diameter and to make the bonding wire of the predetermined length and diameter contact with the plurality of protrusions in two adjacent columns, thereby forming a plurality of continuous bonding connection points in the predetermined length direction of the bonding wire.

3. The bonding structure according to claim 2, characterized in that: The heights of the plurality of protrusions on the bonding interface are proportional to the diameter of the bonding wire.

4. The bonding structure according to claim 2, characterized in that: The protrusion is in a cone shape, and a plurality of nanoparticles are arranged on the surface of the protrusion.

5. The bonding structure according to claim 3, characterized in that: The diameter dimension of the bonding wire and the height dimension of the protrusion include the following matching: The diameter of the bonding wire is 0.5 mm, and the height of the protrusion is 0.05 mm to 0.1 mm; Alternatively, the diameter of the bonding wire is 1 mm, and the height of the protrusion is 0.1 mm to 0.2 mm.

6. A bonding method suitable for ultrasonic welding, characterized in that: The following steps are involved: 6.1 Prepare a bonding wire and a target device; 6.2 providing a bonding interface including a plurality of protrusions on the target device; 6.3 Maintain a predetermined distance between the protrusions, wherein the distance is used to match the bonding wire, so that the bonding wire contacts the protrusion to form a bonding connection point.

7. The bonding method according to claim 6, characterized in that: In step 6.3, the plurality of protrusions on the bonding interface are arranged in an array, and a predetermined spacing is maintained between two adjacent columns of protrusions. The spacing is used to match the bonding wire of a predetermined length and diameter and to make the bonding wire of the predetermined length and diameter contact with the plurality of protrusions in two adjacent columns, thereby forming a plurality of continuous bonding connection points in the predetermined length direction of the bonding wire.

8. The bonding method according to claim 7, characterized in that: The heights of the plurality of protrusions on the bonding interface are proportional to the diameter of the bonding wire.

9. The bonding method according to claim 7, characterized in that: The shape of the protrusion is set to be a cone shape, and a plurality of nanoparticles are set on the surface of the protrusion.

10. The bonding method according to claim 8, characterized in that: The diameter of the bonding wire and the height of the protrusion are set in the following manner: The diameter of the bonding wire is 0.5 mm, and the height of the protrusion is 0.05 mm to 0.1 mm; Alternatively, the diameter of the bonding wire is 1 mm, and the height of the protrusion is 0.1 mm to 0.2 mm.

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