CN209880596U

CN209880596U - WB metal wire

Info

Publication number: CN209880596U
Application number: CN201921039983.4U
Authority: CN
Inventors: 蔡汉龙; 陈明志; 林正忠
Original assignee: Zhongxin Changdian Semiconductor (jiangyin) Co Ltd
Current assignee: SJ Semiconductor Jiangyin Corp
Priority date: 2019-07-04
Filing date: 2019-07-04
Publication date: 2019-12-31
Anticipated expiration: 2029-07-04

Abstract

The utility model provides a WB metal wire, WB metal wire includes the metal wire incision, the metal wire incision is from the surface of WB metal wire to the radial extension of WB metal wire, with the radial dimension that reduces WB metal wire through the metal wire incision, thereby when carrying out the bonding wire technology, can only form a solder joint, then through stretching, make the WB metal wire from the disconnection of metal wire incision department, form the straight line shape metal bonding wire, the UPH of improvement processing procedure, and can improve product quality.

Description

WB metal wire

Technical Field

The utility model relates to a semiconductor manufacturing field especially relates to a WB metal wire.

Background

As integrated circuits become more powerful and have higher performance and integration levels, packaging technology plays an increasingly important role in the production of integrated circuits. Lower cost, more reliable, faster, and higher density circuits are sought after goals for integrated circuit packaging.

Among the existing semiconductor packaging processes, the wire bonding process (WB) is one of the most important and challenging process links. It is generally necessary to design the bonding wires in the package in a straight shape in consideration of the requirements of the specific functions of the package. However, the bonding wire used in the industry at present is a bonding wire with a certain diameter and a smooth surface formed by pulling a wire column for many times, and when the bonding wire is used, a second bonding point (2nd Bond) is needed to be bonded, that is, a special bonding wire machine is used to half-cut the bonding wire in the 2nd Bond manner, and then the bonding wire is stretched and cut to form a required linear shape. However, the welding wire process of 2nd Bond has low UPH, and because the welding wire is bent, a linear welding wire meeting the requirement cannot be formed through stretching, and quality problems such as insufficient welding of the welding wire and the like are easily caused in the process of stretching the welding wire.

In recent years, the development and production technology of semiconductor chips has been rapidly developed, the number of interconnects of a single chip has become more and more complex, and the bonding area allowed by each interconnect has been reduced, and all these changes in key technical parameters mean that a general improvement and promotion of the bonding technology is required to meet new requirements. Wherein the overall improvement and enhancement of the wire bonding process will include improvement of the corresponding wire bonding raw materials, optimization of process parameters and overall quality control.

Therefore, it is necessary to provide a new WB metal line.

SUMMERY OF THE UTILITY MODEL

In view of the above-mentioned shortcomings of the prior art, it is an object of the present invention to provide a WB wire for solving the problems of UPH and quality caused when forming a straight-line shaped bonding wire in the prior art.

To achieve the above and other related objects, the present invention provides a WB metal wire, including a metal wire notch, from a surface of the WB metal wire to a radial extension of the WB metal wire, so as to pass through the metal wire notch to reduce a radial dimension of the WB metal wire.

Optionally, the metal wire cut comprises a groove, and the cross-sectional profile of the groove comprises one or a combination of a V-shape, a U-shape, a square shape, and a trapezoid shape.

Optionally, when the WB metal wire includes only 1 groove in a radial cross section, a percentage of the depth of the groove to the diameter of the WB metal wire ranges from 20% to 80%.

Optionally, the WB metal wire includes N ≧ 2 grooves on a radial cross section, and the N grooves are symmetrically distributed.

Optionally, the metal wire notch includes an annular groove, and the cross-sectional profile of the annular groove includes one or a combination of a V-shape, a U-shape, a square shape, and a trapezoid shape.

Optionally, the metal line notch includes a through hole penetrating through the WB metal line, and a cross-sectional profile of the through hole includes one or a combination of a circle and a polygon.

Optionally, adjacent metal wire cuts have equal spacing in the axial direction of the WB metal wires.

Optionally, the WB metal line includes one of a Cu line, an Au line, a Cu alloy line, an Au alloy line, and a Cu/Au alloy line.

As described above, the utility model discloses a WB metal wire, WB metal wire include the wire incision, the wire incision is from the surface of WB metal wire to the radial extension of WB metal wire to reduce the radial dimension of WB metal wire through the wire incision, thereby when carrying out the bonding wire technology, can only form a solder joint, then through stretching, make the WB metal wire from the disconnection of wire incision department, form the sharp shape metal bonding wire that appears, improve the UPH of processing procedure, and can improve product quality.

Drawings

Fig. 1a to fig. 1d show schematic axial cross-sectional structure diagrams of WB metal wires including grooves according to the present invention.

FIG. 2 is an enlarged schematic view of the section A-A' in FIG. 1 a.

Fig. 3 is a schematic axial cross-sectional view of the WB metal wire of the present invention.

Fig. 4a to 4c are enlarged schematic structural views of a section B-B' in fig. 3.

Fig. 5 is a schematic axial cross-sectional view of a WB metal line including a through hole according to the present invention.

Fig. 6 is an enlarged view of the cross-section C-C' of fig. 5.

Fig. 7 is a schematic process flow diagram illustrating a method for forming a linear metal bonding wire according to the present invention.

Fig. 8 is a schematic view illustrating a process of forming a linear metal bonding wire according to the present invention.

Fig. 9 is a schematic structural diagram after the encapsulation layer is formed according to the present invention.

Fig. 10 is a schematic structural view after the packaging layer is thinned.

Description of the element reference numerals

100 WB metal line

101 metal line cut

200 chip

201 pad

300 welding spot

400 straight-line-shaped metal welding wire

500 riving knife

600 encapsulation layer

X axial direction

Y radial direction

D direction of travel

Angle theta

Detailed Description

The following description of the embodiments of the present invention is provided for illustrative purposes, and other advantages and effects of the present invention will be readily apparent to those skilled in the art from the disclosure herein. The present invention can also be implemented or applied through other different specific embodiments, and various details in the present specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

Please refer to fig. 1 to 10. It should be noted that the drawings provided in the present embodiment are only for illustrating the basic idea of the invention in a schematic manner, and only the components related to the invention are shown in the drawings rather than being drawn according to the number, shape and size of the components in actual implementation, and the form, quantity and proportion of the components in actual implementation may be changed at will, and the layout of the components may be more complicated.

The embodiment provides a WB metal wire, which includes a metal wire notch, where the metal wire notch extends from a surface of the WB metal wire to a radial direction of the WB metal wire, so as to reduce a radial dimension of the WB metal wire through the metal wire notch, so that only one welding point can be formed in a subsequent wire bonding process, and then the WB metal wire is disconnected from the metal wire notch by stretching, so as to form a linear metal bonding wire, thereby improving a UPH of a manufacturing process and improving product quality.

Specifically, as shown in fig. 1a, a WB metal line 100 is provided, where the WB metal line 100 includes an axial direction X and a radial direction Y, and the WB metal line 100 includes a metal line notch 101, where the metal line notch 101 extends from a surface of the WB metal line 100 to the radial direction Y of the WB metal line 100, so as to reduce a radial dimension of the WB metal line 100 through the metal line notch 101. The specific wire diameter of the WB metal wire 100 may be selected according to needs, and is not limited herein. The forming method of the metal line slit 101 may be selected according to the need, for example, a laser method, a mechanical cutting method, etc. may be used, and is not limited herein.

As a further embodiment of this embodiment, the metal wire cut 101 includes a groove having a cross-sectional profile including one or a combination of a V-shape, a U-shape, a square shape, and a trapezoid shape.

Specifically, as shown in fig. 1a to 1d and fig. 2, fig. 2 is an enlarged schematic structural view of a section a-a' in fig. 1 a. The WB metal wire 100 may include only 1 groove in a radial Y cross section, and the cross-sectional profile of the groove may include V-shape (fig. 1a), U-shape (fig. 1b), square shape (fig. 1c), and trapezoid shape (fig. 1 d). In the axial direction X of the WB metal wire 100, the grooves preferably have the same profile, but may also include one of a combination of V, U, square and trapezoid, which is not limited herein.

As a further example of this embodiment, when the WB metal wire 100 includes only 1 groove in a radial Y-section, the range of the percentage of the depth of the groove to the diameter of the WB metal wire includes 20% to 80%.

Specifically, when the percentage is 20%, the stability of the WB metal wire 100 can be improved, and the probability of breakage of the WB metal wire 100 can be reduced, so as to reduce the time consumed for installing the wire by the riving knife due to breakage of the WB metal wire 100; when the percentage is 80%, the process difficulty of subsequently disconnecting the WB metal lines 100 from the metal line cuts 101 can be reduced. In combination with the process requirements, the percentage of the depth of the groove to the diameter of the WB metal line 100 is preferably 50% in this embodiment, so as to reduce the process difficulty of disconnecting the WB metal line 100 on the premise of meeting the stability of the WB metal line 100. The value of the ratio is not limited to this, and may be selected according to the specific material and size of the WB metal line 100, for example, 30%, 45%, 60%, and the like may be adopted.

As a further embodiment of this embodiment, the WB metal line 100 may comprise N ≧ 2 the grooves in a radial Y-section, and N of the grooves are symmetrically distributed.

Specifically, as shown in fig. 3, fig. 4a and fig. 4B are two enlarged schematic structural diagrams of a section B-B' in fig. 3. N of the WB metal wire 100 is 2 on a radial Y section, and the grooves are preferably distributed symmetrically, so that the convenience and the process difficulty of the subsequent wire breaking process are increased. The value of N and the distribution of the grooves are not limited to these, and may be selected according to the requirement, for example, N may be 3, 4, 5, and the like, and N grooves may also be uniformly distributed at equal intervals.

As a further embodiment of this embodiment, the metal wire notch 101 includes a circular groove, and the cross-sectional profile of the circular groove includes one or a combination of a V shape, a U shape, a square shape, and a trapezoid shape.

Specifically, as shown in fig. 3 and 4c, fig. 4c is another enlarged schematic structural diagram of the section B-B' in fig. 3. The metal wire notch 101 in fig. 3 is an annular groove, an axial X-section of the annular groove is V-shaped, and the annular groove and the WB metal wire 100 have the same center, so that the stability of the WB metal wire 100 can be improved, and the process difficulty can be reduced during a subsequent wire cutting process. The cross-sectional shape of the ring groove is not limited to this, and one of a U shape, a square shape and a trapezoid shape may be adopted, and in the axial direction X of the WB metal wire 100, the ring groove preferably has the same shape, but may also have one of combinations formed by the V shape, the U shape, the square shape and the trapezoid shape, and may be specifically selected as needed, and is not limited herein.

As a further embodiment of this embodiment, the metal line notch 101 includes a through hole penetrating through the WB metal line 100, and the cross-sectional profile of the through hole includes one or a combination of a circle and a polygon.

Specifically, as shown in fig. 5 and 6, when the metal line cut 101 is a through hole penetrating through the WB metal line 100, the maximum distance of the through hole in the radial direction Y of the WB metal line 100 needs to be smaller than the diameter of the WB metal line 100, and the percentage of the through hole may be 20% to 80%, preferably 50%, and may be specifically selected according to needs.

As a further example of this embodiment, adjacent wire cuts 101 have equal spacing in the axial direction X of the WB wire 100.

Specifically, the distance between adjacent metal line cuts 101 determines the length of the straight metal bonding line to be formed subsequently, and the arrangement of the distance between adjacent metal line cuts 101 may be selected according to specific needs, and is not limited herein.

As a further example of this embodiment, the WB metal line 100 may include one of a Cu line, an Au line, a Cu alloy line, an Au alloy line, and a Cu/Au alloy line, but is not limited thereto.

As shown in fig. 7, this embodiment further provides a method for forming a linear metal bonding wire, in which the WB metal line 100 is used to form a pad, and then the WB metal line 100 is pulled to be disconnected from the metal line notch 101 to form the linear metal bonding wire, so as to improve UPH of a manufacturing process and improve product quality.

Specifically, as shown in fig. 8, any one of the WB metal wires 100 is provided, and the WB metal wire 100 is mounted on a riving knife 500; providing a chip 200, wherein the surface of the chip 200 comprises a bonding pad 201; connecting the WB metal wire 100 with the bonding pad 201 to form a welding spot 300; and stretching the WB metal line 100 from the welding point 300 along a desired running direction D to break the WB metal line 100 from the metal line notch 101, so as to form a linear metal bonding wire 400. In this embodiment, only one solder joint 300 is formed, and the WB metal line 100 is disconnected from the metal line notch 101 by stretching, so that the linear metal bonding wire 400 can be formed, thereby increasing UPH of the manufacturing process and improving product quality.

As a further embodiment of this embodiment, an included angle between the linear metal bonding wire and the surface of the chip 200 ranges from 45 ° to 90 °.

Specifically, in fig. 8, the running direction D of the riving knife 500 is perpendicular to the surface of the chip 200, so that the included angle θ between the formed linear metal bonding wire 400 and the surface of the chip 200 is 90 °, but not limited thereto, and as shown in fig. 9, the range of the included angle θ between the linear metal bonding wire 400 and the surface of the chip 200 may preferably be 45 ° to 90 °, including 45 °, and the included angle θ may also be equal to 60 °, so as to set the electrical leading-out of the linear metal bonding wire as required.

As a further embodiment of this embodiment, the method further includes a step of forming an encapsulation layer 600 covering the chip 200 and the linear metal bonding wires 400, and a step of thinning the encapsulation layer 600 to expose the linear metal bonding wires 400.

Specifically, as shown in fig. 9, the encapsulation layer 600 covers the surface of the chip 200 and the linear metal bonding wires 400, wherein the encapsulation layer 600 may include one of a polyimide encapsulation layer, a silicone encapsulation layer, and an epoxy encapsulation layer, and the method for forming the encapsulation layer 600 may include one of compression molding, transfer molding, liquid encapsulation, vacuum lamination, and spin coating. Then, as shown in fig. 10, the encapsulation layer 600 may be thinned to expose the linear metal bonding wires 400 in the encapsulation layer 600, wherein the method for thinning the encapsulation layer 600 may include, but is not limited to, a chemical mechanical polishing method.

To sum up, the utility model discloses a WB metal wire, WB metal wire include the metal wire incision, the metal wire incision is from the surface of WB metal wire to the radial extension of WB metal wire to reduce the radial dimension of WB metal wire through the metal wire incision, thereby when carrying out the bonding wire technology, can only form a solder joint, then through stretching, make the WB metal wire from the disconnection of metal wire incision department, form the sharp shape metal bonding wire that appears, improve the UPH of processing procedure, and can improve product quality. Therefore, the utility model effectively overcomes various defects in the prior art and has high industrial utilization value.

The above embodiments are merely illustrative of the principles and effects of the present invention, and are not to be construed as limiting the invention. Modifications and variations can be made to the above-described embodiments by those skilled in the art without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which may be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.

Claims

1. A WB metal line, characterized in that: the WB metal wire comprises a metal wire cut extending from the surface of the WB metal wire in a radial direction of the WB metal wire so as to reduce the radial dimension of the WB metal wire through the metal wire cut.

2. The WB metal line of claim 1, wherein: the metal wire notch comprises a groove, and the cross section appearance of the groove comprises one or a combination of V shape, U shape, square shape and trapezoid shape.

3. The WB metal line of claim 2, wherein: when the WB metal wire includes only 1 groove on a radial cross section, the range of the percentage of the depth of the groove to the diameter of the WB metal wire includes 20% to 80%.

4. The WB metal line of claim 2, wherein: the WB metal wire comprises N or more than 2 grooves on a radial section, and the N grooves are symmetrically distributed.

5. The WB metal line of claim 1, wherein: the metal wire notch comprises an annular groove, and the section appearance of the annular groove comprises one or a combination of V shape, U shape, square shape and trapezoid shape.

6. The WB metal line of claim 1, wherein: the metal wire cut comprises a through hole penetrating through the WB metal wire, and the cross-sectional shape of the through hole comprises one or a combination of a circle and a polygon.

7. The WB metal line of claim 1, wherein: in the axial direction of the WB metal wires, the adjacent metal wire cuts are spaced at equal intervals.

8. The WB metal line of claim 1, wherein: the WB metal wire comprises one of a Cu wire, an Au wire, a Cu alloy wire, an Au alloy wire and a Cu/Au alloy wire.