阅读说明：本技术 一种固晶焊线结构 (Die bonding wire structure ) 是由 周建华 易巨荣 张振强 于 2020-12-16 设计创作，主要内容包括：本发明涉及LED加工技术领域,公开了一种固晶焊线结构,包括晶片支架,晶片支架包括正极焊盘、负极焊盘和分隔支架,正极焊盘上设有第一晶片,负极焊盘上设有第二晶片,第一晶片与正极焊盘通过第一焊线连接,第一晶片与第二晶片之间通过第二焊线连接,第三晶片与负极焊盘之间通过第三焊线连接,第一焊线、第二焊线和第三焊线包括第一焊球、第一弧段、第二弧段、第三弧段、第四弧段和第二焊球,且焊线在俯视状态下整体为J形；焊线在侧视状态下,第一弧段朝向远离第二焊球的方向凸起,第二弧段向下凹陷,第三弧段向上凸起,第四弧段向下凹陷。本发明能够有效分散、缓冲焊线的三维应力,提高焊线的抗冷热冲击能力与耐拉扯能力。(The invention relates to the technical field of LED processing, and discloses a die bonding wire structure which comprises a wafer support, wherein the wafer support comprises an anode bonding pad, a cathode bonding pad and a separation support, a first wafer is arranged on the anode bonding pad, a second wafer is arranged on the cathode bonding pad, the first wafer is connected with the anode bonding pad through a first bonding wire, the first wafer is connected with the second wafer through a second bonding wire, a third wafer is connected with the cathode bonding pad through a third bonding wire, the first bonding wire, the second bonding wire and the third bonding wire comprise a first welding ball, a first arc section, a second arc section, a third arc section, a fourth arc section and a second welding ball, and the bonding wire is integrally J-shaped in a overlooking state; the bonding wire is at the side view state, and first segmental arc orientation is protruding far away from the direction of second solder ball, and the second segmental arc is sunken downwards, and the third segmental arc is upwards protruding, and the fourth segmental arc is sunken downwards. The invention can effectively disperse and buffer the three-dimensional stress of the welding wire and improve the cold and hot impact resistance and the pulling resistance of the welding wire.)

1. A die bonding wire structure is characterized by comprising a wafer support, wherein the wafer support comprises an anode bonding pad, a cathode bonding pad and a separation support for separating the anode bonding pad from the cathode bonding pad, a first wafer is arranged on the anode bonding pad, a second wafer is arranged on the cathode bonding pad, the first wafer is connected with the anode bonding pad through a first bonding wire, the first wafer is connected with the second wafer through a second bonding wire, the third wafer is connected with the cathode bonding pad through a third bonding wire, the first bonding wire, the second bonding wire and the third bonding wire comprise a first welding ball, a first arc section, a second arc section, a third arc section, a fourth arc section and a second welding ball which are sequentially connected, and the wire type of the bonding wire is integrally J-shaped in a overlooking state; in a side view state of the wire type of the bonding wire, the first arc section protrudes towards a direction far away from the second solder ball, the second arc section is downwards concave, the third arc section protrudes upwards, and the fourth arc section is downwards concave.

2. The die bond wire bond structure of claim 1, wherein the first segment projects half of the first solder ball away from the second solder ball.

3. The die bond wire bonding structure of claim 1, wherein the second arc segment is recessed downward by 2-3 positions of the wire diameter of the second arc segment.

4. The die bond wire bonding structure according to claim 3, wherein the third arc segment protrudes upwards by 2-3 positions of the wire diameter of the third arc segment.

5. The die bond wire structure of claim 1, wherein the area of the positive bond pad is equal to the area of the negative bond pad.

6. The die bond wire bond structure of claim 5, wherein the first die and the second die are symmetrically disposed on opposite sides of the separation frame.

7. The die bond wire bonding structure according to claim 6, wherein the distance between the first wafer and the separation support is 0.05mm to 0.18mm, and the distance between the second wafer and the separation support is 0.05mm to 0.18 mm.

8. The die bond wire bond structure of claim 1, wherein a transition section is connected between the first solder ball and the first arc section, the transition section extending upward from the first solder ball and being in smooth transition with the first arc section.

9. The die bond wire bond structure of claim 1, wherein the first, second and third bonding wires are metal wires.

10. The die bond wire structure of claim 1, wherein the first solder ball of the first wire is bonded to the positive pad or the negative electrode of the first die, the second solder ball of the first wire is bonded to the negative electrode of the first die or the positive pad, the first solder ball of the second wire is bonded to the negative electrode of the second die or the positive electrode of the first die, the second solder ball of the second wire is bonded to the positive electrode of the first die or the negative electrode of the second die, the first solder ball of the third wire is bonded to the negative pad or the positive electrode of the second die, and the second solder ball of the third wire is bonded to the positive electrode of the second die or the negative pad.

Technical Field

The invention relates to the technical field of LED processing, in particular to a die bonding wire structure.

Background

The LED is used as a novel light source, has the advantages of low energy consumption, no pollution, small size, convenience and flexibility in use and the like, and is widely applied to various fields; the bonding wire is a very important link in LED production, and the LED bracket and the wafer are welded through the metal thin wire, so that the wafer is electrically connected with the outside to emit light. In the process of welding the wire, the welding wire expands with heat and contracts with cold due to the physical property of the welding wire, and the existing welding wire is relatively straight, so that the welding wire is pulled under the action of cold and heat shock and external force, stress is generated in the welding wire, and the welding wire and the welding point are easily broken to cause the lamp to be dead.

Disclosure of Invention

The invention aims to provide a die bonding wire structure which can effectively disperse and buffer the three-dimensional stress of a bonding wire and improve the cold and hot impact resistance and the pulling resistance of the bonding wire.

In order to achieve the above object, the invention provides a die bonding wire structure, which includes a wafer support, wherein the wafer support includes an anode pad, a cathode pad and a separation support for separating the anode pad from the cathode pad, a first wafer is disposed on the anode pad, a second wafer is disposed on the cathode pad, the first wafer is connected to the anode pad through a first bonding wire, the first wafer is connected to the second wafer through a second bonding wire, the third wafer is connected to the cathode pad through a third bonding wire, the first bonding wire, the second bonding wire and the third bonding wire include a first solder ball, a first arc segment, a second arc segment, a third arc segment, a fourth arc segment and a second solder ball which are connected in sequence, and the line type of the bonding wire is "J" shape in a top view state; in a side view state of the wire type of the bonding wire, the first arc section protrudes towards a direction far away from the second solder ball, the second arc section is downwards concave, the third arc section protrudes upwards, and the fourth arc section is downwards concave.

As a preferable aspect of the present invention, the first arc segment protrudes by half the position of the first solder ball in a direction away from the second solder ball.

Preferably, the second arc segment is recessed downwards by 2-3 positions of the line diameter of the second arc segment.

Preferably, the third arc segment protrudes upwards by 2-3 positions of the wire diameter of the third arc segment.

In a preferred embodiment of the present invention, the area of the positive electrode pad is equal to the area of the negative electrode pad.

In a preferred embodiment of the present invention, the first wafer and the second wafer are symmetrically disposed on both sides of the separation frame.

In a preferred embodiment of the present invention, the distance between the first wafer and the separation holder is 0.05mm to 0.18mm, and the distance between the second wafer and the separation holder is 0.05mm to 0.18 mm.

As a preferred aspect of the present invention, a transition section is connected between the first solder ball and the first arc section, and the transition section extends upward from the first solder ball and is in smooth transition with the first arc section.

As a preferable aspect of the present invention, the first bonding wire, the second bonding wire, and the third bonding wire are metal wires.

As a preferable aspect of the present invention, the first solder ball of the first bonding wire is welded to the positive electrode pad or the negative electrode of the first wafer, the second solder ball of the first bonding wire is welded to the negative electrode of the first wafer or the positive electrode pad, the first solder ball of the second bonding wire is welded to the negative electrode of the second wafer or the positive electrode of the first wafer, the second solder ball of the second bonding wire is welded to the positive electrode of the first wafer or the negative electrode of the second wafer, the first solder ball of the third bonding wire is welded to the negative electrode pad or the positive electrode of the second wafer, and the second solder ball of the third bonding wire is welded to the positive electrode of the second wafer or the negative electrode pad.

Compared with the prior art, the die bonding wire structure provided by the embodiment of the invention has the beneficial effects that:

in the embodiment of the invention, the wire type of the welding wire is integrally J-shaped in an overlooking state, the damage of a ceramic nozzle to the welding wire in the welding wire process can be reduced, the first arc is in a convex state and can buffer the stress of the welding wire in the vertical direction and the longitudinal direction, the continuous wave band formed by matching the second arc section and the third arc section is in a non-tightening state and can buffer the stress of the welding wire in the longitudinal direction and the transverse direction, the welding wire can be more smoothly transited to the second welding ball through the fourth arc section, the change damage between the tail end of the welding wire and the second welding ball is reduced, and the improvement of the pulling force and the pushing force of the second welding ball is; therefore, the invention can effectively disperse and buffer the three-dimensional stress of the welding wire in the vertical direction, the horizontal direction and the longitudinal direction, avoid the stress buffer dead angle, improve the cold and hot impact resistance and the pulling resistance of the welding wire, improve the yield of the LED and prolong the service life of the wafer.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings of the embodiments will be briefly described below.

FIG. 1 is a schematic structural diagram of a die bond wire structure according to the present invention;

FIG. 2 is a front view of a first wire arc;

FIG. 3 is a top view of a first wire arc;

in the figure, 1 is a wafer holder; 11 is a positive electrode pad; 12 is a negative electrode bonding pad; 13 is a separation bracket; 2 is a first wafer; 3 is a second wafer; 4 is a first bonding wire; 5 is a second bonding wire; 6 is a third bonding wire; 41 is a first solder ball; 42 is a first arc segment; 43 is a second arc segment; 44 is a third arc segment; 45 is a fourth arc segment; 46 is a second solder ball; and 47 is a transition section.

Detailed Description

The following detailed description of embodiments of the invention is provided in connection with the accompanying drawings and examples. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are only for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

As shown in fig. 1 to fig. 3, a die bonding wire structure according to a preferred embodiment of the present invention includes a die holder 1, where the die holder 1 includes a positive bonding pad 11, a negative bonding pad 12, and a separation frame 13 for separating the positive bonding pad 11 from the negative bonding pad 12, a first die 2 is disposed on the positive bonding pad 11, a second die 3 is disposed on the negative bonding pad 12, the first die 2 is connected to the positive bonding pad 11 through a first bonding wire 4, the first die 2 is connected to the second die 3 through a second bonding wire 5, the third die is connected to the negative bonding pad 12 through a third bonding wire 6, the first bonding wire 4, the second bonding wire 5, and the third bonding wire 6 include a first solder ball 41, a first arc 42, a second arc 43, a third arc 44, a fourth arc 45, and a second solder ball 46, which are sequentially connected, the line type of the welding line is integrally J-shaped in a overlooking state; in the wire bonding pattern, in a side view, the first arc section 42 is convex in a direction away from the second solder ball 46, the second arc section 43 is concave downward, the third arc section 44 is convex upward, and the fourth arc section 45 is concave downward. It should be noted that the top view direction is a direction perpendicular to the plane of the bonding pad, and the side view direction is shown as a direction in fig. 1; the vertical direction is the Z direction in fig. 2, the horizontal direction is the X direction in fig. 2, and the longitudinal direction is the Y direction in fig. 3.

It can be seen that the wire type of the bonding wire in the embodiment of the present invention is overall "J" shape in a top view state, which can reduce the damage of the ceramic nozzle to the bonding wire in the bonding wire process, and the first arc is a convex state, which can buffer the stress of the bonding wire in the vertical and longitudinal directions, and the continuous wave band formed by the matching of the second arc section 43 and the third arc section 44 is in a non-tight state, which can buffer the stress of the bonding wire in the longitudinal and transverse directions, and the bonding wire can be more smoothly transited to the second solder ball 46 through the fourth arc section 45, so as to reduce the variation damage between the tail end of the bonding wire and the second solder ball 46, which is helpful to improve the pulling force and pushing force of; therefore, the invention can effectively disperse and buffer the three-dimensional stress of the welding wire in the vertical direction, the horizontal direction and the longitudinal direction, avoid the stress buffer dead angle, improve the cold and hot impact resistance and the pulling resistance of the welding wire, improve the yield of the LED and prolong the service life of the wafer.

It should be further noted that the first chip 2, the second chip 3, the first bonding wire 4, the second bonding wire 5, and the third bonding wire 6 are all coated with LED glue.

Illustratively, the first arc section 42 protrudes by half the first solder ball 41 in the direction away from the second solder ball 46, so that the vertical and longitudinal stresses on the bonding wire caused by thermal expansion and contraction of the bonding wire and the thermal expansion and contraction of the LED glue during operation can be effectively buffered.

Illustratively, the second arc segments 43 are recessed downwards at the positions of 2-3 wire diameters of the second arc segments 43; the third arc section 44 protrudes upwards for 2-3, and the position of the line diameter of the third arc section 44 can effectively buffer the vertical and transverse stress of the bonding wire generated by expansion with heat and contraction with cold of the bonding wire and expansion with heat and contraction with cold of the LED glue during working.

Illustratively, the area of the positive electrode pad 11 is equal to the area of the negative electrode pad 12; the first wafer 2 and the second wafer 3 are symmetrically arranged on two sides of the separation bracket 13; the distance between the first wafer 2 and the separation support 13 is 0.05-0.18 mm, the distance between the second wafer 3 and the separation support 13 is 0.05-0.18 mm, and the separation support 13 is of a standard size, so that the second bonding wire 5 can be ensured to be proper in length, the reliability is ensured, the phenomenon that the second bonding wire is too short to effectively buffer stress and break is avoided, the possibility that the second bonding wire is too long and the quality is increased to cause the second bonding wire to be stressed under the vibration and impact environment to increase the breakage is avoided, and consumable materials can be reduced so as to reduce the raw material cost.

Illustratively, a transition section 47 is connected between the first solder ball 41 and the first arc section 42, the transition section 47 extends upward from the first solder ball 41 and is in smooth transition with the first arc section 42, and by arranging the transition section 47, the first arc can be buffered, so that the first arc is prevented from being broken due to the fact that the first arc is directly bent from the first solder ball 41, and the reliability of the die attach wire structure is improved.

Illustratively, the first bonding wire 4, the second bonding wire 5 and the third bonding wire 6 are metal wires, which may be gold wires, silver wires, copper wires or alloy wires; in the present embodiment, the first bonding wire 4, the second bonding wire 5, and the third bonding wire 6 are preferably gold wires, which can ensure good conductivity of the bonding wires, and have high stability, are not easy to age, and prolong the service life of the LED.

Illustratively, the first solder ball 41 of the first bonding wire 4 is soldered to the positive electrode pad 11 or the negative electrode of the first die 2, the second solder ball 46 of the first bonding wire 4 is soldered to the negative electrode of the first die 2 or the positive electrode pad 11, the first solder ball of the second bonding wire 5 is soldered to the negative electrode of the second die 3 or the positive electrode of the first die 2, the second solder ball of the second bonding wire 5 is soldered to the positive electrode of the first die 2 or the negative electrode of the second die 3, the first solder ball of the third bonding wire 6 is soldered to the negative electrode pad 12 or the positive electrode of the second die 3, and the second solder ball of the third bonding wire 6 is soldered to the positive electrode of the second die 3 or the negative electrode pad 12.

As shown in fig. 1, in this embodiment, the first solder ball 41 of the first bonding wire 4 is soldered to the negative electrode of the first die 2, the second solder ball of the first bonding wire 4 is soldered to the positive electrode pad 11, the first solder ball of the second bonding wire 5 is soldered to the positive electrode of the first die 2, the second solder ball of the second bonding wire 5 is soldered to the negative electrode of the second die 3, the first solder ball of the third bonding wire 6 is soldered to the positive electrode of the second die 3, and the second solder ball of the third bonding wire 6 is soldered to the negative electrode pad 12. Specifically, the end of the fourth arc segment 45 of the first bonding wire 4 extends downward and is close to the negative electrode bonding pad 12, the end of the fourth arc segment of the second bonding wire 5 extends downward and is close to the second wafer 3, and the end of the fourth arc segment of the third bonding wire 6 extends downward and is close to the positive electrode bonding pad 11, so that the damage caused by the change between the end of the bonding wire and the second bonding ball 46 is effectively reduced.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "connected" and "connected" are to be interpreted broadly, e.g., as being fixed or detachable or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and substitutions can be made without departing from the technical principle of the present invention, and these modifications and substitutions should also be regarded as the protection scope of the present invention.