Semiconductor wire bonding process and semiconductor device

Abstract

The application discloses a semiconductor wire welding processing method and a semiconductor device. The semiconductor wire welding processing method is used for welding intersecting first and second wires between a base island and an inner pin. One of the wires is welded to the base island through a flat solder ball, and the other wire is welded to the inner pin through a flat solder ball. The two wires are respectively deflected to two sides of a central axis and form acute angles with a separation line. Molten plastic packaging material is used to flow into a mold cavity along a mold flow channel and wrap the two wires. The second wire is located in a direction close to the input of the plastic packaging material at an intersection. The wire welding processing method is used for welding two intersecting wires. The plastic packaging material is injected along a specific mold flow direction. The two wires are deformed in different directions of the separation line. The intersection of the two wires is more closely contacted. Even if the fish tail solder joint is detached, the electrical connection between the base island and the outer lead wire is not affected. The reliability of the wire welding in the semiconductor device is greatly improved.

Description

Technical Field

[0001] This invention relates to the field of semiconductor packaging technology, and in particular to a semiconductor wire bonding process and a semiconductor device. Background Technology

[0002] Currently, in the packaging process of semiconductor integrated circuits, bonding wires are required to electrically connect the product frame base island and internal pins. Gold, copper, or alloy wires are typically used as bonding wires (conductors). However, semiconductor devices packaged using existing processes often exhibit fishtail solder joint (second solder joint) detachment, leading to product failure and low packaging reliability. Therefore, existing technologies for wire bonding suffer from low wire bonding reliability. Summary of the Invention

[0003] This invention provides a semiconductor wire bonding processing method and a semiconductor device, aiming to solve the problem of low wire bonding reliability in existing wire bonding processing methods.

[0004] In a first aspect, embodiments of this application provide a semiconductor wire bonding processing method, wherein the wire bonding processing method includes:

[0005] The first wire is soldered between the base island and the inner pin, and the first wire and the base island are soldered together by a flat solder ball and a ball-burning process to form a metal eutectic compound.

[0006] The second wire is soldered between the base island and the inner pin. The second wire and the inner pin are soldered together by a flat solder ball and a ball-burning process to form a metal eutectic compound. The second wire crosses over the first wire and intersects with the first wire.

[0007] Alternatively, the second wire can be soldered between the base island and the inner pin, and the second wire and the base island can be soldered together using a flat solder ball and a ball-burning process to form a metal eutectic compound;

[0008] The first wire is soldered between the base island and the inner pin. The first wire and the inner pin are soldered together by a flat solder ball and a burn-in ball process to form a metal eutectic compound. The first wire passes over the second wire and intersects with the second wire.

[0009] Furthermore, molten molding compound enters the mold cavity along the mold flow channel and wraps the first and second wires; the mold flow direction of the molding compound entering the mold is the direction in which the first and second wires pass sequentially on the side of the inner pin; the second wire is located near the direction of the molding compound input at the intersection point; the second wire and the first wire intersect and are electrically connected at the gap between the base island and the inner pin, and the length of the second wire is greater than that of the first wire; the first and second wires are deflected to both sides of the central axis, the central axis being a straight line extending from the intersection point of the two wires to both sides of the base island and the inner pin; the first wire rotates clockwise by a first included angle to coincide with the separator line, and the second wire rotates counterclockwise by a second included angle to coincide with the separator line, the separator line being a straight line that separates the gap between the base island and the inner pin and is perpendicular to the central axis; both the first and second included angles are acute angles.

[0010] Secondly, embodiments of this application also provide a semiconductor device, wherein the semiconductor device is processed by the wire bonding processing method described in the first aspect above, and the semiconductor device includes a base island, an inner lead, a first wire, a second wire, and a molding compound;

[0011] The two ends of the first wire are respectively welded and fixed to the base island and the inner pin; the two ends of the second wire are respectively welded and fixed to the base island and the inner pin; the first wire and the second wire intersect and are electrically connected at the gap between the base island and the inner pin; the plastic encapsulation is wrapped around the outside of the first wire and the second wire;

[0012] One conductor is soldered to the base island via a flat solder ball, and the other conductor is soldered to the inner pin via a flat solder ball. The first and second conductors deflect to opposite sides of a central axis, which is a straight line extending from the intersection of the two conductors towards both sides of the base island and the inner pin. The first conductor rotates clockwise by a first included angle to coincide with the separator line, and the second conductor rotates counterclockwise by a second included angle to coincide with the separator line. The separator line is a straight line perpendicular to the central axis that separates the gap between the base island and the inner pin. The first and second included angles are equal and both are 45° ≤ and < 90°. The second conductor at the intersection is located closer to the molding compound input direction.

[0013] The first conductor is composed of a first vertical segment, a first arc, and a first inclined segment; the first arc connects the first vertical segment and the first inclined segment.

[0014] The end of the first vertical segment is fixed to a welding seat formed by a flat welding ball, and the end of the first inclined segment is fixed to a fish tail welding point.

[0015] The second conductor consists of a second vertical segment, a second arc, and a second inclined segment; the second arc connects the second vertical segment and the second inclined segment.

[0016] The end of the second vertical segment is fixed to a welding seat formed by a flat solder ball, and the end of the second inclined segment is fixed to a fishtail solder point; the angle between the second inclined segment and the horizontal plane is smaller than the angle between the first inclined segment and the horizontal plane.

[0017] The lateral distance between the solder joints at both ends of the second conductor and the dividing line is greater than the lateral distance between the solder joints at both ends of the first conductor and the dividing line.

[0018] This invention provides a semiconductor wire bonding processing method and a semiconductor device. The method involves bonding an intersecting first wire and a second wire between a base island and an inner lead. One wire is bonded to the base island via a flat solder ball, and the other wire is bonded to the inner lead via a flat solder ball. Both wires are deflected to opposite sides of the central axis, with acute angles between them and the separator line. Molten molding compound flows into the mold cavity along the mold flow channel and wraps around the two wires. The second wire is positioned near the direction of the molding compound input at the intersection point. This wire bonding processing method obtains two intersecting wires through bonding. A metal eutectic compound is formed through flat solder ball and solder ball processes to improve the reliability of the solder joint and prevent detachment. Molding compound is injected along a specific mold flow direction. The difference in deformation of the two wires in the direction of the separator line ensures a tighter contact at the intersection point. Even if the fishtail solder joint detaches, it does not affect the electrical connection between the base island and the outer lead, significantly improving the reliability of wire bonding in semiconductor devices. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a flowchart of a semiconductor wire bonding process provided in an embodiment of the present invention.

[0021] Figure 2 A three-dimensional structural diagram of a semiconductor device provided in an embodiment of the present invention;

[0022] Figure 3A top view of the semiconductor device provided in an embodiment of the present invention;

[0023] Figure 4 This is a side view of a semiconductor device provided in an embodiment of the present invention;

[0024] Figure 5 This is another top view of the semiconductor device provided in an embodiment of the present invention;

[0025] Figure 6 Another three-dimensional structural diagram of the semiconductor device provided in the embodiment of the present invention;

[0026] Figure 7 Another top view structural diagram of the semiconductor device provided in an embodiment of the present invention;

[0027] Figure 8 This is another side view of the semiconductor device provided in an embodiment of the present invention;

[0028] Figure 9 This is another top view of the semiconductor device provided in an embodiment of the present invention.

[0029] Reference numerals: 1. Base island; 2. Inner pin; 3. First conductor; 4. Second conductor; 31. First vertical segment; 32. First arc; 33. First inclined segment; 41. Second vertical segment; 42. Second arc; 43. Second inclined segment; 34. First solder joint; 44. Second solder joint; 5. Central axis; 6. Separator line; 35. First fishtail solder joint; 45. Second fishtail solder joint. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0032] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used in this specification and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes such combinations.

[0033] Please see Figure 1 As shown in the figure, this application discloses a semiconductor wire bonding process method, wherein the wire bonding process method includes steps S110 to S130, as well as steps S210 and S220.

[0034] S110. The first wire is soldered between the base island and the inner pin. The first wire and the inner pin of the base island are soldered together to form a metal eutectic compound through a flat solder ball and a ball-burning process.

[0035] The first wire 3 is soldered between the base island 1 and the inner pin 2. The first wire 3 and the base island 1 are soldered together using a flat solder ball and solder ball process to form a metal eutectic compound. The first wire 3 can be soldered between the base island 1 and the inner pin 2. In such cases... Figure 2 In the first embodiment shown, the first conductor 3 and the base island 1 are welded together by a flat solder ball and a ball-burning process to form a metal eutectic compound. This metal eutectic compound is used to fix the first conductor 3 with a first soldering seat 34. The first conductor 3 and the inner pin 2 are welded together by a conventional soldering process to form a fishtail solder joint.

[0036] The solder joint is formed by a metal film layer between a flat solder ball and a base island or inner lead. A eutectic layer is formed between the bottom of the solder joint and the metal film layer; that is, the eutectic layer is located at the junction of the solder joint and the metal film layer, and the eutectic layer is relatively thin. Because a eutectic layer is formed at the bottom of the solder joint, the bonding force between the solder joint and the metal film layer can be significantly increased. Ordinary fishtail solder joints do not have a eutectic layer; fishtail solder joints rely solely on temperature, power, and time for bonding, resulting in weaker bonding force.

[0037] S120. The second wire is soldered between the base island and the inner pin. The second wire and the base island are soldered together by a flat solder ball and a ball-burning process to form a metal eutectic compound. The second wire crosses over the first wire and intersects with the first wire.

[0038] Based on similar processing steps, the second wire 4 can be soldered between the base island 1 and the inner pin 2, and during the soldering operation, the second wire 4 crosses over the first wire 3. Figure 2In the first embodiment shown, the second wire 4 and the inner pin 2 are welded together by a flat solder ball and a ball-burning process to form a metal eutectic compound. This metal eutectic compound is used to fix the second wire 4 to the second soldering seat 44. The second wire 4 and the base island 1 are welded together by conventional welding to form a fishtail solder joint.

[0039] like Figure 1 As shown, steps S110 and S120 can also be replaced by steps S210 and S220.

[0040] S210. A second wire is soldered between the base island and the inner pin. The second wire and the base island are soldered together using a flat solder ball and a burn-in ball process to form a metal eutectic compound. S220. A first wire is soldered between the base island and the inner pin. The first wire and the inner pin are soldered together using a flat solder ball and a burn-in ball process to form a metal eutectic compound. The first wire crosses over the second wire and intersects with the second wire.

[0041] In such Figure 6 In the second embodiment shown, the first conductor 3 and the inner pin 2 are soldered together using a flat solder ball and a ball-burning process to form a metal eutectic compound. This metal eutectic compound serves as the first soldering base 34 for fixing the first conductor 3. The first conductor 3 and the base island 1 are connected by conventional soldering to form a fishtail solder joint. Figure 6 In the second embodiment shown, the second conductor 4 and the base island 1 are welded together by a flat solder ball and a ball-burning process to form a metal eutectic compound. This metal eutectic compound is used to fix the second conductor 4 to the second soldering seat 44. The second conductor 4 and the inner pin 2 are welded together by conventional soldering to form a fishtail solder joint.

[0042] After the two wires are soldered, one wire can be soldered to the base island 1 via a flat solder ball, and the other wire can be soldered to the inner pin 2 via a flat solder ball. Furthermore, the second wire 4 and the first wire 3 intersect and are electrically connected at the gap between the base island 1 and the inner pin 2; to achieve a tight electrical connection, the length of the second wire 4 can be set to be greater than that of the first wire 3; for example... Figure 3 and Figure 7 As shown, the first conductor 3 and the second conductor 4 deflect to both sides of the central axis 5, which is a straight line formed by extending from the intersection of the two conductors to both sides of the base island 1 and the inner pin 2.

[0043] Specifically, such as Figure 3 and Figure 7As shown, the first conductor 3 rotates clockwise by a first included angle θ1 to coincide with the separator line 6, and the second conductor 4 rotates counterclockwise by a second included angle θ2 to coincide with the separator line 6. The separator line 6 is a straight line perpendicular to the central axis 5, separating the gap between the base island 1 and the inner pin 2. The first included angle θ1 and the second included angle θ2 are equal and both are acute angles. Furthermore, the lateral distance between the solder joints at both ends of the second conductor 4 and the separator line 6 can be set to be greater than the lateral distance between the solder joints at both ends of the first conductor 3 and the separator line 6. The specific structure is as follows: Figure 3 and Figure 7 As shown.

[0044] In a specific embodiment, in order to make the first wire 3 and the second wire 4 fit tightly together to improve the electrical connection effect, the first included angle θ1 and the second included angle θ2 can both be set to 45°≤ and <90°. In a preferred embodiment, the first included angle θ1 and the second included angle θ2 can both be set to 75°≤ and <90°.

[0045] Specifically, such as Figure 4 and Figure 8 As shown, the first conductor 3 is composed of a first vertical segment 31, a first arc 32, and a first inclined segment 33; the first arc 32 connects the first vertical segment 31 and the first inclined segment 33; the end of the first vertical segment 31 is fixed to a welding seat formed by a flat solder ball, and the end of the first inclined segment 33 is fixed to a fishtail solder joint; the second conductor 4 is composed of a second vertical segment 41, a second arc 42, and a second inclined segment 43; the second arc 42 connects the second vertical segment 41 and the second inclined segment 43; the end of the second vertical segment 41 is fixed to a welding seat formed by a flat solder ball, and the end of the second inclined segment 43 is fixed to a fishtail solder joint; the angle between the second inclined segment 43 and the horizontal plane is smaller than the angle between the first inclined segment 33 and the horizontal plane.

[0046] S130. Molten molding compound is used to enter the mold cavity along the mold flow channel and wrap the first wire and the second wire.

[0047] Molten molding compound enters the mold cavity along the mold flow channel and wraps around the first lead 3 and the second lead 4; the mold flow direction of the molding compound entering the mold is the direction in which the inner lead 2 passes sequentially through the first lead 3 and the second lead 4; the second lead 4 is located at the intersection in the direction close to the input of the molding compound. In a specific embodiment, the mold flow direction is parallel to the separator line 6.

[0048] like Figures 2 to 5 The first embodiment of this application is shown, as follows: Figure 3As shown in the attached diagram from a top view, the central axis 5 and the dividing line 6 intersect perpendicularly, forming four quadrants, denoted as the first quadrant, second quadrant, third quadrant, and fourth quadrant. The solder joint between the first conductor 3 and the base island 1 can be placed in the second quadrant, and this solder joint is welded using flat solder balls (the solder balls can be made as flat as possible) and a solder ball burning process to form a metal eutectic compound (the flat solder balls and the surface metal of the base island 1 form a eutectic compound). Then, controlling the first included angle θ1 corresponding to the first conductor 3 to be 45°≤ and < 90°, the solder joint between the first conductor 3 and the inner pin 2 is placed in the fourth quadrant and welded (using conventional welding to form a fishtail solder joint) to form the first fishtail solder joint 35, as shown. Figure 3 As shown, the first conductor 3 is formed by welding between the second and fourth quadrants.

[0049] In the first embodiment, to further enhance the bonding of the second wire 4, the second wire 4 crosses over the first wire 3, such as... Figure 2 As shown; the solder joint between the second conductor 4 and the inner pin 2 is placed in the first quadrant, and this solder joint is welded using a flat solder ball and ball-burning process to form a metal eutectic compound (the flat solder ball and the surface metal of the inner pin 2 form a eutectic compound); then, controlling the second included angle θ2 corresponding to the second conductor 4 to be 45°≤ and < 90°, the solder joint between the second conductor 4 and the base island 1 is placed in the third quadrant and welded (using conventional welding process to form a fishtail solder joint) to form the second fishtail solder joint 45, as shown. Figure 3 As shown, the second conductor 4 is formed by welding between the first and third quadrants.

[0050] During the welding process, the first wire 3 and the second wire 4 intersect. Due to the aforementioned positional relationship, the second wire 4 is closer to the direction of the molding compound input at the intersection point compared to the first wire 3. During the welding process, the vertical height H2 of the second wire 4 can be set to 0.9 times the vertical height H1 of the first wire 3. Figure 4 As shown; the length of the second conductor 4 is 1.2-1.5 times the length of the first conductor 3.

[0051] During product molding, the molding compound, molten at high temperature, enters the mold cavity through the mold flow channel to encapsulate the internal structure of the product. The molten molding compound impacts the two welded wires in the mold flow direction. Because the second wire 4 is longer than the first wire 3, the second wire 4 deforms more after the impact, meaning it deforms more along the separator line 6. The first wire 3 deforms less along the separator line 6, resulting in a tighter contact at the intersection of the two wires after molding. The specific structure of the first wire 3 and the second wire 4 after molding is as follows: Figure 5 As shown.

[0052] like Figures 6 to 9 The following is another first embodiment of this application, as shown. Figure 7 As shown in the attached diagram from a top view, the central axis 5 and the dividing line 6 intersect perpendicularly, forming four quadrants, denoted as the first quadrant, second quadrant, third quadrant, and fourth quadrant. The solder joint between the first conductor 3 and the base island 1 can be placed in the second quadrant and soldered (using conventional soldering to form a fishtail solder joint) to form the first fishtail solder joint 35. Then, controlling the first included angle θ1 corresponding to the first conductor 3 to be 45°≤ and < 90°, the solder joint between the first conductor 3 and the inner pin 2 is placed in the fourth quadrant. This solder joint is then soldered using flat solder balls (the solder balls can be made as flat as possible) and a ball-burning process to form a metal eutectic compound (the flat solder balls and the surface metal of the base island 1 form a eutectic compound), as shown. Figure 7 As shown, the first conductor 3 is formed by welding between the second and fourth quadrants.

[0053] In the second embodiment, to further increase the bonding of the second wire 4, the first wire 3 crosses over the second wire 4, such as... Figure 6 As shown; the solder joint between the second conductor 4 and the inner pin 2 is placed in the first quadrant and soldered (using conventional soldering to form a fishtail solder joint) to form the second fishtail solder joint 45; then, controlling the second included angle θ2 corresponding to the second conductor 4 to be 45°≤ and < 90°, the solder joint between the second conductor 4 and the base island 1 is placed in the third quadrant, and this solder joint is soldered using a flat solder ball and ball-burning process to form a metal eutectic compound (the flat solder ball and the surface metal of the inner pin 2 form a eutectic compound), as shown. Figure 7 As shown, the second conductor 4 is formed by welding between the first and third quadrants.

[0054] During the welding process, the first wire 3 and the second wire 4 intersect. Due to the aforementioned positional relationship, the second wire 4 is closer to the direction of the molding compound input at the intersection point compared to the first wire 3. During the welding process, the vertical height H1 of the first wire 3 can be set to 0.9 times the vertical height H2 of the second wire 4. Figure 8 As shown; the length of the first conductor 3 is 0.6-0.8 times the length of the second conductor 4.

[0055] During product molding, the molding compound, molten at high temperature, enters the mold cavity through the mold flow channel to encapsulate the internal structure of the product. The molten molding compound impacts the two welded wires in the mold flow direction. Because the second wire 4 is longer than the first wire 3, the second wire 4 deforms more after the impact, meaning it deforms more along the separator line 6. The first wire 3 deforms less along the separator line 6, resulting in a tighter contact at the intersection of the two wires after molding. The specific structure of the first wire 3 and the second wire 4 after molding is as follows: Figure 9As shown.

[0056] After the device is encapsulated using the above two welding methods, if both fishtail solder joints of the two wires (bonding wires) inside the product detach abnormally during use, the electrical connectivity of the product will remain unaffected because the solder ball on the base island 1 and the solder ball on the inner pin 2 are still connected through the intersection of the two wires. This avoids the problem of device failure due to the detachment of the fishtail solder joints, thus greatly improving the reliability of wire welding.

[0057] This invention also provides a semiconductor device, which is fabricated using the wire bonding method described in the above embodiments, such as... Figure 2 and Figure 5As shown, the semiconductor device includes a base island 1, an inner lead 2, a first wire 3, a second wire 4, and a molding compound; both ends of the first wire 3 are soldered and fixed to the base island 1 and the inner lead 2, respectively; both ends of the second wire 4 are soldered and fixed to the base island 1 and the inner lead 2, respectively; the first wire 3 and the second wire 4 intersect and are electrically connected at the gap between the base island 1 and the inner lead 2; the molding compound is disposed on the outside of the first wire 3 and the second wire 4; one of the wires is connected to the base island 1 via a flat solder ball. The first wire 3 and the second wire 4 are soldered to the inner pin 2 via a flat solder ball; the first wire 3 and the second wire 4 are deflected to both sides of the central axis 5, which is a straight line extending from the intersection of the two wires to both sides of the base island 1 and the inner pin 2; the first wire 3 rotates clockwise by a first included angle to coincide with the separator line 6, and the second wire 4 rotates counterclockwise by a second included angle to coincide with the separator line 6, which is a straight line perpendicular to the central axis 5 that separates the gap between the base island 1 and the inner pin 2; The first included angle and the second included angle are equal and both are 45°≤ and <90°; the second conductor 4 is located at the intersection in the direction close to the molding compound input; the first conductor 3 is composed of a first vertical segment 31, a first arc 32 and a first inclined segment 33; the first arc 32 connects the first vertical segment 31 and the first inclined segment 33; the end of the first vertical segment 31 is fixed to a welding seat formed by a flat solder ball, and the end of the first inclined segment 33 is fixed to a fishtail solder joint; the second conductor 4 is composed of a second vertical segment 41 and a second arc 42. It consists of a second vertical segment 41 and a second inclined segment 43; the second arc 42 connects the second vertical segment 41 and the second inclined segment 43; the end of the second vertical segment 41 is fixed to a welding seat formed by a flat solder ball, and the end of the second inclined segment 43 is fixed to a fishtail solder point; the angle between the second inclined segment 43 and the horizontal plane is smaller than the angle between the first inclined segment 33 and the horizontal plane; the lateral distance between the solder points at both ends of the second conductor 4 and the dividing line 6 is greater than the lateral distance between the solder points at both ends of the first conductor 3 and the dividing line 6.

[0058] In such Figures 2 to 5In the first embodiment shown, the diameters of the first wire 3 and the second wire 4 are both 20 μm. The solder joint between the first wire 3 and the base is placed in the second quadrant, and the first included angle θ1 corresponding to the first wire 3 is set to 85°. The solder joint between the first wire 3 and the inner pin 2 is placed in the fourth quadrant, thereby forming the first wire 3 by soldering between the second and fourth quadrants. The first solder joint 34 is formed by soldering the first wire 3 to the base, and the first fishtail solder joint 35 is formed by soldering the first wire 3 to the inner pin 2. During the soldering process, the vertical height H1 of the first wire 3 is controlled to be 500 μm, and the length of the first wire 3 is set to 1.0 mm.

[0059] A second bonding wire 4 is added, crossing over the first bonding wire 3. The solder joint between the second bonding wire 4 and the base is placed in the third quadrant, and the second included angle θ2 corresponding to the second bonding wire 4 is set to 85°. The solder joint between the second bonding wire 4 and the inner lead 2 is placed in the first quadrant, thus forming the second bonding wire 4 by soldering between the first and third quadrants. A second fishtail solder joint 45 is formed between the second bonding wire 4 and the base, and a second soldering base 44 is formed between the second bonding wire 4 and the inner lead 2. During the soldering process, the vertical height H2 of the second bonding wire 4 is controlled to be 450 μm, and the length of the second bonding wire 4 is set to 1.2 mm. The first bonding wire 3 and the second bonding wire 4 intersect at the middle section, and the second bonding wire 4 is located near the direction of the molding compound input at the intersection point. The semiconductor device structure obtained after molding is as follows. Figure 5 As shown.

[0060] In such Figures 6 to 9 In the second embodiment shown, the diameters of the first wire 3 and the second wire 4 are both 20 μm. The solder joint between the first wire 3 and the base is placed in the second quadrant, and the first included angle θ1 corresponding to the first wire 3 is set to 85°. The solder joint between the first wire 3 and the inner pin 2 is placed in the fourth quadrant, thereby forming the first wire 3 by soldering between the second and fourth quadrants. The first solder joint 34 is formed by soldering the first wire 3 and the inner pin 2, and the first fishtail solder joint 35 is formed by soldering the first wire 3 and the base. During the soldering process, the vertical height H1 of the first wire 3 is controlled to be 450 μm, and the length of the first wire 3 is set to 0.96 mm.

[0061] A second bonding wire 4 is added, crossing over the first bonding wire 3. The solder joint between the second bonding wire 4 and the base is placed in the third quadrant, and the second included angle θ2 corresponding to the second bonding wire 4 is set to 85°. The solder joint between the second bonding wire 4 and the inner lead 2 is placed in the first quadrant, thus forming the second bonding wire 4 by soldering between the first and third quadrants. The second bonding pad 44 is then formed by soldering the second bonding wire 4 to the base, and the second fishtail solder joint 45 is formed by soldering the second bonding wire 4 to the inner lead 2. During the soldering process, the vertical height H2 of the second bonding wire 4 is controlled to be 500 μm, and the length of the second bonding wire 4 is set to 1.2 mm. The first bonding wire 3 and the second bonding wire 4 intersect at the middle section, and the second bonding wire 4 is located near the direction of the molding compound input at the intersection point. The semiconductor device structure obtained after molding is as follows. Figure 9 As shown.

[0062] Compared with existing technologies, this invention claims protection for a semiconductor wire bonding processing method and a semiconductor device. This wire bonding processing method involves bonding an intersecting first wire and a second wire between a base island and an inner lead. One wire is bonded to the base island via a flat solder ball, and the other wire is bonded to the inner lead via a flat solder ball. Both wires are deflected to opposite sides of the central axis, with acute angles between them and the separator line. Molten molding compound flows into the mold cavity along the mold flow channel and wraps around the two wires. The second wire is positioned near the direction of the molding compound input at the intersection point. This wire bonding processing method obtains two intersecting wires through bonding, and uses flat solder balls and a solder ball process to form a metal eutectic compound, improving the reliability of the solder joint and preventing detachment. Injecting molding compound along a specific mold flow direction utilizes the difference in deformation of the two wires in the direction of the separator line to ensure a tighter contact at the intersection point. Even if the fishtail solder joint detaches, it does not affect the electrical connection between the base island and the outer lead, significantly improving the reliability of wire bonding in semiconductor devices.

[0063] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A semiconductor wire bonding process, characterized in that, The wire welding process includes: The first wire is soldered between the base island and the inner pin, and the first wire and the base island are soldered together by a flat solder ball and a ball-burning process to form a metal eutectic compound. The second wire is soldered between the base island and the inner pin. The second wire and the inner pin are soldered together by a flat solder ball and a ball-burning process to form a metal eutectic compound. The second wire crosses over the first wire and intersects the first wire to form an intersection point. Alternatively, the second wire can be soldered between the base island and the inner pin, and the second wire and the base island can be soldered together using a flat solder ball and a ball-burning process to form a metal eutectic compound; The first wire is soldered between the base island and the inner pin. The first wire and the inner pin are soldered together by a flat solder ball and a burn-in ball process to form a metal eutectic compound. The first wire crosses over the second wire and intersects the second wire to form an intersection point. Furthermore, molten molding compound enters the mold cavity along the mold flow channel and wraps the first and second wires; the mold flow direction of the molding compound entering the mold is the direction in which the first and second wires pass sequentially on the side of the inner pin; the second wire is located near the direction of the molding compound input at the intersection point; the second wire and the first wire intersect and are electrically connected at the gap between the base island and the inner pin, and the length of the second wire is greater than that of the first wire; the first and second wires are deflected to both sides of the central axis, the central axis being a straight line extending from the intersection point of the two wires to both sides of the base island and the inner pin; the first wire rotates clockwise by a first included angle to coincide with the separator line, and the second wire rotates counterclockwise by a second included angle to coincide with the separator line, the separator line being a straight line that separates the gap between the base island and the inner pin and is perpendicular to the central axis; both the first and second included angles are acute angles.

2. The semiconductor wire bonding process according to claim 1, characterized in that, The first conductor is composed of a first vertical segment, a first arc, and a first inclined segment; the first arc connects the first vertical segment and the first inclined segment. The end of the first vertical segment is fixed to a welding seat formed by a flat welding ball, and the end of the first inclined segment is fixed to a fish tail welding point. The second conductor consists of a second vertical segment, a second arc, and a second inclined segment; the second arc connects the second vertical segment and the second inclined segment. The end of the second vertical segment is fixed to a welding seat formed by a flat welding ball, and the end of the second inclined segment is fixed to a fishtail welding point; the angle between the second inclined segment and the horizontal plane is smaller than the angle between the first inclined segment and the horizontal plane.

3. The semiconductor wire bonding process according to claim 2, characterized in that, The lateral distance between the solder joints at both ends of the second conductor and the dividing line is greater than the lateral distance between the solder joints at both ends of the first conductor and the dividing line.

4. The semiconductor wire bonding process according to claim 2 or 3, characterized in that, The direction of the mold flow is parallel to the dividing line.

5. The semiconductor wire bonding process according to claim 4, characterized in that, Both the first included angle and the second included angle are 45°≤ and <90°.

6. The semiconductor wire bonding process according to claim 5, characterized in that, Both the first included angle and the second included angle are 75°≤ and <90°.

7. The semiconductor wire bonding process according to claim 6, characterized in that, The first included angle is equal to the second included angle.

8. The semiconductor wire bonding process according to claim 7, characterized in that, When the second conductor crosses over the first conductor, the vertical height of the second conductor is 0.9 times the vertical height of the first conductor; the length of the second conductor is 1.2-1.5 times the length of the first conductor.

9. The semiconductor wire bonding process according to claim 7, characterized in that, When the first conductor crosses over the second conductor, the vertical height of the first conductor is 0.9 times the vertical height of the second conductor; the length of the first conductor is 0.6-0.8 times the length of the second conductor.

10. A semiconductor device, characterized in that, The semiconductor device is fabricated using the wire bonding process described in any one of claims 1-9, and the semiconductor device includes a base island, inner leads, a first wire, a second wire, and a plastic encapsulation. The two ends of the first wire are respectively welded and fixed to the base island and the inner pin; the two ends of the second wire are respectively welded and fixed to the base island and the inner pin; the first wire and the second wire intersect and are electrically connected at the gap between the base island and the inner pin; the plastic encapsulation is wrapped around the outside of the first wire and the second wire; One conductor is soldered to the base island via a flat solder ball, and the other conductor is soldered to the inner pin via a flat solder ball. The first and second conductors deflect to opposite sides of a central axis, which is a straight line extending from the intersection of the two conductors towards both sides of the base island and the inner pin. The first conductor rotates clockwise by a first included angle to coincide with the separator line, and the second conductor rotates counterclockwise by a second included angle to coincide with the separator line. The separator line is a straight line perpendicular to the central axis that separates the gap between the base island and the inner pin. The first and second included angles are equal and both are 45° ≤ and < 90°. The second conductor at the intersection is located closer to the molding compound input direction. The first conductor is composed of a first vertical segment, a first arc, and a first inclined segment; the first arc connects the first vertical segment and the first inclined segment. The end of the first vertical segment is fixed to a welding seat formed by a flat welding ball, and the end of the first inclined segment is fixed to a fish tail welding point. The second conductor consists of a second vertical segment, a second arc, and a second inclined segment; the second arc connects the second vertical segment and the second inclined segment. The end of the second vertical segment is fixed to a welding seat formed by a flat solder ball, and the end of the second inclined segment is fixed to a fishtail solder point; the angle between the second inclined segment and the horizontal plane is smaller than the angle between the first inclined segment and the horizontal plane. The lateral distance between the solder joints at both ends of the second conductor and the dividing line is greater than the lateral distance between the solder joints at both ends of the first conductor and the dividing line.

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