Semiconductor wire welding processing method and semiconductor device

Abstract

The invention discloses a semiconductor wire welding processing method and a semiconductor device.According to the wire welding processing method, a first wire and a second wire which intersect with each other are welded between a base island and an inner pin, one wire is welded to the base island through a flat welding ball, and the other wire is welded to the inner pin through a flat welding ball; the two wires deflect towards the two sides of the central axis respectively, the included angles between the two wires and the separation line are acute angles, molten plastic packaging materials flow into the mold cavity along the mold flow channel and wrap the two wires, and the intersection point of the second wire is located in the direction close to the input direction of the plastic packaging materials. According to the conducting wire welding processing method, the two intersecting conducting wires are obtained through welding processing, the molding compound is injected in the specific mold flow direction, the contact of the intersecting positions of the two conducting wires is tighter through deformation difference of the two conducting wires in the direction of the separation line, even if a fishtail welding spot falls off, the electric connection between the base island and the outer lead is not affected, and the welding quality is improved. And the reliability of wire welding in the semiconductor device is greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor packaging, and in particular to a semiconductor wire welding processing method and a semiconductor device. Background Art

[0002] At present, in the packaging process of semiconductor integrated circuits, bonding wires need to be set between the product frame base island and the inner pins for electrical connection. Gold wires, copper wires or alloy wires are usually used as bonding wires (conductors). When the semiconductor devices are packaged using the existing packaging process, the fishtail solder joints (second solder joints) of the wires usually fall off, which causes the product to fail and cannot be used, resulting in low reliability of packaging processing. Therefore, the technical methods used for wire welding processing in the prior art have the problem of low wire welding reliability. Summary of the invention

[0003] The embodiments of the present invention provide a semiconductor wire welding processing method and a semiconductor device, aiming to solve the problem of low wire welding reliability existing in the technical methods used for wire welding processing in the prior art methods.

[0004] In a first aspect, an embodiment of the present application provides a semiconductor wire welding processing method, wherein the wire welding processing method comprises:

[0005] Welding a first wire between the base island and the inner pin, wherein the first wire and the base island are welded by a flat solder ball and a ball sintering process to form a metal eutectic compound;

[0006] Welding a second wire between the base island and the inner lead, the second wire and the inner lead are welded by a flat solder ball and a sintering process to form a metal eutectic compound, and the second wire crosses over the first wire and intersects with the first wire;

[0007] Alternatively, the second wire is welded between the base island and the inner lead, and the second wire and the base island are welded by a flat solder ball and a ball sintering process to form a metal eutectic compound;

[0008] Welding the first wire between the base island and the inner pin, the first wire and the inner pin are welded by flat solder balls and sintering process to form a metal eutectic compound, the first wire crosses over the second wire and intersects with the second wire;

[0009] And, using molten plastic encapsulation material to enter the mold cavity of the mold along the mold flow channel and wrap the first wire and the second wire; the mold flow direction of the plastic encapsulation material entering the mold is the direction in which the first wire and the second wire are passed through the side of the inner pin in sequence; the second wire is located at the intersection point close to the direction of the plastic encapsulation material input; the second wire intersects and electrically connects with the first wire at the gap between the base island and the inner pin, and the length of the second wire is greater than the first wire; the first wire and the second wire are respectively deflected to both sides of the central axis, and the central axis is a straight line formed by extending the intersection of the two wires to both sides of the base island and the inner pin; the first wire is rotated clockwise by a first angle to coincide with the dividing line, and the second wire is rotated counterclockwise by a second angle to coincide with the dividing line, and the dividing line is a straight line that separates the gap between the base island and the inner pin and is perpendicular to the central axis; the first angle and the second angle are both acute angles.

[0010] In a second aspect, an embodiment of the present application further provides a semiconductor device, wherein the semiconductor device is processed by the wire welding processing method described in the first aspect above, and the semiconductor device includes a base island, an inner pin, a first wire, a second wire and a plastic package;

[0011] The two ends of the first wire are respectively welded and fixed on the base island and the inner pin; the two ends of the second wire are respectively welded and fixed on 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 package is wrapped and arranged on the outside of the first wire and the second wire;

[0012] 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 first wire and the second wire are deflected to both sides of the central axis respectively, and the central axis is a straight line formed by extending the intersection of the two wires to both sides of the base island and the inner pin; the first wire is rotated clockwise by a first angle to coincide with the separation line, and the second wire is rotated counterclockwise by a second angle to coincide with the separation line, and the separation line is a straight line that separates the gap between the base island and the inner pin and is perpendicular to the central axis; the first angle and the second angle are equal and are both 45°≤ and <90°; the second wire is located at the intersection close to the direction of the plastic packaging material input;

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

[0014] The end of the first vertical section is fixed to a welding seat formed by a flat welding ball, and the end of the first inclined section is fixed to a fishtail welding point;

[0015] The second conductive line is composed of a second vertical segment, a second line arc and a second inclined segment; the second line arc connects the second vertical segment and the second inclined segment;

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

[0017] The lateral distances between the welding points at both ends of the second wire and the separation line are greater than the lateral distances between the welding points at both ends of the first wire and the separation line.

[0018] The embodiment of the present invention provides a semiconductor wire welding processing method and a semiconductor device. The wire welding processing method welds the first wire and the second wire that intersect between the base island and the inner pin, wherein one wire 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 deflected to both sides of the central axis and the angles between them and the separation line are both acute angles. The molten plastic encapsulation material flows into the mold cavity along the mold flow channel and wraps the two wires. The second wire is located at the intersection close to the direction of the plastic encapsulation material input. The above-mentioned wire welding processing method obtains two intersecting wires through welding processing, and welds them through flat solder balls and sintering ball processes to form a metal eutectic compound to improve the reliability of the solder joint and prevent it from falling off; the plastic encapsulation material is injected along a specific mold flow direction, and the deformation difference of the two wires in the direction of the separation line is used to make the intersection of the two wires more closely contacted. Even if the fishtail solder joint falls off, it does not affect the electrical connection between the base island and the outer lead, which greatly improves the reliability of wire welding in the semiconductor device. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying any creative work.

[0020] Figure 1 A method flow chart of a semiconductor wire welding method provided by an embodiment of the present invention;

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

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

[0023] Figure 4 A side structural diagram of a semiconductor device provided by an embodiment of the present invention;

[0024] Figure 5 Another top view of the semiconductor device provided by the embodiment of the present invention;

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

[0026] Figure 7 Another top view of the semiconductor device provided by the embodiment of the present invention;

[0027] Figure 8 Another side view of the semiconductor device provided by the embodiment of the present invention;

[0028] Fig. 9 Another top view of the semiconductor device provided by the embodiment of the present invention.

[0029] Figure numerals: 1. base island; 2. inner pin; 3. first conductor; 4. second conductor; 31. first vertical segment; 32. first line arc; 33. first inclined segment; 41. second vertical segment; 42. second line arc; 43. second inclined segment; 34. first welding seat; 44. second welding seat; 5. central axis; 6. dividing line; 35. first fishtail welding point; 45. second fishtail welding point. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work 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 "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0032] It should also be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present 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 further understood that the term "and / or" used in the present specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes these combinations.

[0033] See also Figure 1 As shown in the figure, an embodiment of the present application discloses a semiconductor wire welding processing method, wherein the wire welding processing method includes steps S110 to S130 and steps S210 and S220.

[0034] S110, welding a first wire between the base island and the inner pin, and welding the first wire to the inner pin of the base island through a flat solder ball and a ball sintering process to form a metal eutectic compound.

[0035] The first wire 3 is welded between the base island 1 and the inner lead 2. The first wire 3 and the base island 1 are welded by a flat solder ball and a sintering process to form a metal eutectic compound. The first wire 3 can be welded between the base island 1 and the inner lead 2. Figure 2 In the first embodiment shown, the first wire 3 and the base island 1 are welded by flat solder balls and sintering process to form a metal eutectic compound, and the metal eutectic compound is used to fix the first wire 3 to the first welding seat 34, and the first wire 3 and the inner pin 2 are formed into a fishtail solder joint by conventional welding process.

[0036] The soldering base is formed by the metal film layer between the flat solder ball and the base island or the inner pin, and a common gold layer is formed between the bottom of the soldering base and the metal film layer, that is, the common gold layer is located at the junction of the soldering base and the metal film layer, and the common gold layer is relatively thin. Since the common gold layer is formed at the bottom of the soldering base, the bonding strength between the soldering base and the metal film layer can be greatly increased. Ordinary fishtail solder joints do not have a common gold layer. Fishtail solder joints are only crimped by temperature, power, time, etc., and the bonding strength is relatively weak.

[0037] S120, welding a second wire between the base island and the inner pin, the second wire and the base island are welded by a flat solder ball and a sintering process to form a metal eutectic compound, and 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 welded between the base island 1 and the inner lead 2, and during the welding operation, the second wire 4 passes over the first wire 3. Figure 2In the first embodiment shown, the second wire 4 and the inner pin 2 are welded by a flat solder ball and a sintering process to form a metal eutectic compound, and the metal eutectic compound is used to fix the second wire 4 to the second welding seat 44, and a fishtail solder joint is formed between the second wire 4 and the base island 1 by conventional welding treatment.

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

[0040] S210, welding the second wire between the base island and the inner pin, and forming a metal eutectic compound between the second wire and the base island by means of a flat solder ball and a sintering process; S220, welding the first wire between the base island and the inner pin, and forming a metal eutectic compound between the first wire and the inner pin by means of a flat solder ball and a sintering process, and the first wire passes over the second wire and intersects with the second wire.

[0041] In such Figure 6 In the second embodiment shown, the first wire 3 and the inner lead 2 are welded by a flat solder ball and a sintering process to form a metal eutectic compound, and the metal eutectic compound is used to fix the first wire 3 to the first welding seat 34, and the first wire 3 and the base island 1 are welded by a conventional welding process to form a fishtail solder joint. Figure 6 In the second embodiment shown, the second wire 4 and the base island 1 are welded by flat solder balls and sintering process to form a metal eutectic compound, and the metal eutectic compound is used to fix the second wire 4 to the second welding seat 44, and the second wire 4 and the inner pin 2 are formed into a fishtail solder joint by conventional welding process.

[0042] After the two wires are welded, one of the wires can be welded to the base island 1 through a flat solder ball, and the other wire can be welded to the inner pin 2 through a flat solder ball. 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 the first wire 3. Figure 3 and Figure 7 As shown, the first conductive wire 3 and the second conductive wire 4 are respectively deflected to both sides of a central axis 5 , and the central axis 5 is a straight line extending from the intersection of the two conductive wires to both sides of the base island 1 and the inner pin 2 .

[0043] Specifically, Figure 3 and Figure 7As shown, the first conductor 3 is rotated clockwise by a first angle θ1 to coincide with the separation line 6, and the second conductor 4 is rotated counterclockwise by a second angle θ2 to coincide with the separation line 6. The separation line 6 is a straight line that separates the gap between the base island 1 and the inner pin 2 and is perpendicular to the central axis 5; the first angle θ1 and the second 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 separation 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 separation line 6. The specific setting structure is as follows: Figure 3 and Figure 7 shown.

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

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

[0046] S130, using molten plastic encapsulation material to enter the mold cavity of the mold along the mold flow channel and wrap the first wire and the second wire.

[0047] The molten plastic encapsulation material is used to enter the mold cavity of the mold along the mold flow channel and wrap the first wire 3 and the second wire 4; the mold flow direction of the plastic encapsulation material entering the mold is the direction in which the inner pin 2 passes through the first wire 3 and the second wire 4 in sequence; the second wire 4 is located at the intersection close to the direction in which the plastic encapsulation material is input. In a specific embodiment, the mold flow direction is parallel to the separation line 6.

[0048] like Figures 2 to 5 The first embodiment of the present application is shown as follows. Figure 3As shown, in the top-view drawing, the central axis 5 and the dividing line 6 can be perpendicularly intersected and divided into four quadrants, which are respectively recorded as the first quadrant, the second quadrant, the third quadrant and the fourth quadrant. The solder joint between the first wire 3 and the base island 1 can be placed in the second quadrant, and the solder joint is welded by a flat solder ball (the solder ball can be made as flat as possible) and a sintering process to form a metal eutectic compound (the flat solder ball and the surface metal of the base island 1 form a eutectic compound); then, the first angle θ1 corresponding to the first wire 3 is controlled to be 45°≤ and <90°, and the solder joint between the first wire 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 a first fishtail solder joint 35, as shown in FIG. Figure 3 That is, the first wire 3 is formed by welding between the second quadrant and the fourth quadrant.

[0049] In the first embodiment, in order to further increase 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 wire 4 and the inner pin 2 is placed in the first quadrant, and the solder joint is welded by a flat solder ball and a sintering 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, the second angle θ2 corresponding to the second wire 4 is controlled to be 45°≤ and <90°, and the solder joint between the second wire 4 and the base island 1 is placed in the third quadrant and welded (using conventional welding to form a fishtail solder joint) to form a second fishtail solder joint 45, as shown Figure 3 That is, the second wire 4 is formed by welding between the first quadrant and the third quadrant.

[0050] During the welding process, the first wire 3 intersects with the second wire 4. Due to the above positional relationship, the second wire 4 is closer to the direction of the plastic material input at the intersection than 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 wire 4 is 1.2-1.5 times the length of the first wire 3.

[0051] When the product is sealed, the melted sealing material in a high temperature environment enters the mold cavity through the mold flow channel to wrap the internal structure of the product. The melted sealing material will impact the two welded wires in the mold flow direction. Since the second wire 4 is longer than the first wire 3, the second wire 4 will be more deformed after the material impact, that is, the second wire 4 will be more deformed along the dividing line 6, and the first wire 3 will be less deformed along the dividing line 6, so that the intersection of the two wires is more closely contacted after the sealing. The specific structure of the first wire 3 and the second wire 4 after the sealing is as follows: Figure 5 shown.

[0052] like Figures 6 to 9 Another first implementation mode of the present application is shown as follows: Figure 7 As shown, in the top-view drawing, the central axis 5 and the dividing line 6 can be perpendicularly intersected and divided into four quadrants, which are respectively recorded as the first quadrant, the second quadrant, the third quadrant and the fourth quadrant. The solder joint between the first wire 3 and the base island 1 can be placed in the second quadrant and welded (using conventional welding to form a fishtail solder joint) to form a first fishtail solder joint 35; then, the first angle θ1 corresponding to the first wire 3 is controlled to be 45°≤ and <90°, and the solder joint between the first wire 3 and the inner pin 2 is placed in the fourth quadrant, and the solder joint is welded by a flat solder ball (the solder ball can be made as flat as possible) and a sintering process to form a metal eutectic compound (the flat solder ball forms a eutectic compound with the surface metal of the base island 1), as shown in FIG. Figure 7 That is, the first wire 3 is formed by welding between the second quadrant and the fourth quadrant.

[0053] In the second embodiment, in order 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 wire 4 and the inner pin 2 is placed in the first quadrant and welded (using conventional welding to form a fishtail solder joint) to form a second fishtail solder joint 45; then, the second angle θ2 corresponding to the second wire 4 is controlled to be 45°≤ and <90°, the solder joint between the second wire 4 and the base island 1 is placed in the third quadrant, and the solder joint is welded by a flat solder ball and a sintering 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 That is, the second wire 4 is formed by welding between the first quadrant and the third quadrant.

[0054] During the welding process, the first wire 3 intersects with the second wire 4. Due to the above positional relationship, the second wire 4 is closer to the direction of the plastic material input at the intersection than 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 wire 3 is 0.6-0.8 times the length of the second wire 4.

[0055] When the product is sealed, the melted sealing material in a high temperature environment enters the mold cavity through the mold flow channel to wrap the internal structure of the product. The melted sealing material will impact the two welded wires in the mold flow direction. Since the second wire 4 is longer than the first wire 3, the second wire 4 will be more deformed after the material impact, that is, the second wire 4 will be more deformed along the dividing line 6, and the first wire 3 will be less deformed along the dividing line 6, so that the intersection of the two wires is more closely contacted after the sealing. The specific structure of the first wire 3 and the second wire 4 after the sealing is as follows: Fig. 9shown.

[0056] After the device is encapsulated using the above two welding processing methods, if the two fishtail solder joints in the two wires (bonding wires) inside the product fall off abnormally during subsequent use of the product, since an electrical connection path is still formed from the solder ball on the base island 1 to the solder ball on the inner pin 2 through the intersection of the two wires, the electrical connectivity of the product is still unaffected at this time; thereby avoiding the problem of device failure and unusability due to the falling of the fishtail solder joints, and greatly improving the reliability of wire welding.

[0057] The embodiment of the present invention further provides a semiconductor device, which is manufactured by the wire welding method described in the above embodiment. Figure 2 and Figure 5As shown, the semiconductor device includes a base island 1, an inner pin 2, a first wire 3, a second wire 4 and a plastic package; the two ends of the first wire 3 are respectively welded and fixed to the base island 1 and the inner pin 2; the two ends of the second wire 4 are respectively welded and fixed to the base island 1 and the inner pin 2; 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 pin 2; the plastic package is wrapped around the outside of the first wire 3 and the second wire 4; one of the wires is connected to the base island 1 through a flat solder ball The first wire 3 and the second wire 4 are respectively deflected to the two sides of the central axis 5, and the central axis 5 is a straight line formed by extending the intersection of the two wires to the base island 1 and the two sides of the inner pin 2; the first wire 3 is rotated clockwise by a first angle to coincide with the separation line 6, and the second wire 4 is rotated counterclockwise by a second angle to coincide with the separation line 6, and the separation line 6 is a straight line that separates the gap between the base island 1 and the inner pin 2 and is perpendicular to the central axis 5; The first angle and the second angle are equal and both are 45°≤ and <90°; the second conductor 4 is located at the intersection close to the direction of the plastic packaging material input; the first conductor 3 is composed of a first vertical section 31, a first arc 32 and a first inclined section 33; the first arc 32 connects the first vertical section 31 and the first inclined section 33; the end of the first vertical section 31 is fixed on a welding seat formed by a flat solder ball, and the end of the first inclined section 33 is fixed on a fishtail solder joint; the second conductor 4 is composed of a second vertical section 41, a second arc 42 and a second inclined section 43; the second arc 42 connects the second vertical section 41 and the second inclined section 43; the end of the second vertical section 41 is fixed on a welding seat formed by a flat solder ball, and the end of the second inclined section 43 is fixed on a fishtail welding point; the angle between the second inclined section 43 and the horizontal plane is smaller than the angle between the first inclined section 33 and the horizontal plane; the lateral distances between the welding points at both ends of the second wire 4 and the dividing line 6 are both greater than the lateral distances between the welding points at both ends of the first wire 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 set to 20um, the welding point between the first wire 3 and the base is placed in the second quadrant, and the first angle θ1 corresponding to the first wire 3 is set to 85°; the welding point between the first wire 3 and the inner pin 2 is placed in the fourth quadrant, so that the first wire 3 is welded between the second quadrant and the fourth quadrant. Then, the first wire 3 is welded to the base to form a first welding seat 34, and the first wire 3 is welded to the inner pin 2 to form a first fishtail welding point 35; during the welding process, the vertical height H1 of the first wire 3 is controlled to be 500um, and the length of the first wire 3 is set to 1.0mm.

[0059] Add a bonding second wire 4, the second wire 4 crosses over the first wire 3, the welding point between the second wire 4 and the base is placed in the third quadrant, and the second angle θ2 corresponding to the second wire 4 is set to 85°; the welding point between the second wire 4 and the inner pin 2 is placed in the first quadrant, so as to form the second wire 4 by welding between the first quadrant and the third quadrant. Then the second wire 4 and the base are welded to form a second fishtail welding point 45, and the second wire 4 and the inner pin 2 are welded to form a second welding seat 44. During the welding process, the vertical height H2 of the second wire 4 is controlled to be 450um, and the length of the second wire 4 is set to 1.2mm. The first wire 3 and the second wire 4 intersect in the middle section, and the second wire 4 is located at the intersection close to the direction of the plastic packaging material input. The structure of the semiconductor device obtained after plastic packaging is as follows Figure 5 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 set to 20um, the welding point between the first wire 3 and the base is placed in the second quadrant, and the first angle θ1 corresponding to the first wire 3 is set to 85°; the welding point between the first wire 3 and the inner pin 2 is placed in the fourth quadrant, so that the first wire 3 is welded between the second quadrant and the fourth quadrant. Then the first wire 3 and the inner pin 2 are welded to form a first welding seat 34, and the first wire 3 and the base are welded to form a first fishtail welding point 35; during the welding process, the vertical height H1 of the first wire 3 is controlled to be 450um, and the length of the first wire 3 is set to 0.96mm.

[0061] Add a bonding second wire 4, the second wire 4 crosses over the first wire 3, the welding point between the second wire 4 and the base is placed in the third quadrant, and the second angle θ2 corresponding to the second wire 4 is set to 85°; the welding point between the second wire 4 and the inner pin 2 is placed in the first quadrant, so as to form the second wire 4 by welding between the first quadrant and the third quadrant. Then the second wire 4 and the base are welded to form a second welding seat 44, and the second wire 4 and the inner pin 2 are welded to form a second fishtail welding point 45. During the welding process, the vertical height H2 of the second wire 4 is controlled to be 500um, and the length of the second wire 4 is set to 1.2mm. The first wire 3 and the second wire 4 intersect in the middle section, and the second wire 4 is located at the intersection close to the direction of the plastic packaging material input. The structure of the semiconductor device obtained after plastic packaging is as follows Fig. 9 shown.

[0062] Compared with the prior art, the present invention claims protection for a semiconductor wire welding processing method and a semiconductor device, wherein the wire welding processing method welds the first wire and the second wire intersecting between the base island and the inner pin, wherein one wire 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, and the two wires are deflected to both sides of the central axis and the angles between them and the separation line are both acute angles, and the molten plastic encapsulation material is used to flow into the mold cavity along the mold flow channel and wrap the two wires, and the second wire is located at the intersection close to the direction of the plastic encapsulation material input. The above-mentioned wire welding processing method obtains two intersecting wires through welding processing, and welds them through flat solder balls and sintering ball processes to form a metal eutectic compound to improve the reliability of the solder joint and prevent it from falling off; the plastic encapsulation material is injected along a specific mold flow direction, and the deformation difference of the two wires in the direction of the separation line is used to make the intersection of the two wires more closely contacted, even if the fishtail solder joint falls off, it does not affect the electrical connection between the base island and the outer lead, which greatly improves the reliability of wire welding in the semiconductor device.

[0063] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A semiconductor wire welding method, characterized in that: The wire welding processing method comprises: Welding a first wire between the base island and the inner pin, wherein the first wire and the base island are welded by a flat solder ball and a ball sintering process to form a metal eutectic compound; Welding a second wire between the base island and the inner lead, the second wire and the inner lead are welded by a flat solder ball and a sintering process to form a metal eutectic compound, and the second wire crosses over the first wire and intersects with the first wire; Alternatively, the second wire is welded between the base island and the inner lead, and the second wire and the base island are welded by a flat solder ball and a ball sintering process to form a metal eutectic compound; Welding the first wire between the base island and the inner pin, the first wire and the inner pin are welded by flat solder balls and sintering process to form a metal eutectic compound, the first wire crosses over the second wire and intersects with the second wire; And, using molten plastic encapsulation material to enter the mold cavity of the mold along the mold flow channel and wrap the first wire and the second wire; the mold flow direction of the plastic encapsulation material entering the mold is the direction in which the first wire and the second wire are passed through the side of the inner pin in sequence; the second wire is located at the intersection point close to the direction of the plastic encapsulation material input; the second wire intersects and electrically connects with the first wire at the gap between the base island and the inner pin, and the length of the second wire is greater than the first wire; the first wire and the second wire are respectively deflected to both sides of the central axis, and the central axis is a straight line formed by extending the intersection of the two wires to both sides of the base island and the inner pin; the first wire is rotated clockwise by a first angle to coincide with the dividing line, and the second wire is rotated counterclockwise by a second angle to coincide with the dividing line, and the dividing line is a straight line that separates the gap between the base island and the inner pin and is perpendicular to the central axis; the first angle and the second angle are both acute angles.

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

3. The semiconductor wire bonding method according to claim 2, characterized in that: The lateral distances between the welding points at both ends of the second wire and the separation line are greater than the lateral distances between the welding points at both ends of the first wire and the separation line.

4. The semiconductor wire bonding method according to claim 2 or 3, characterized in that: The mold flow direction is parallel to the separation line.

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

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

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

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

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

10. A semiconductor device, characterized in that: The semiconductor device is obtained by using the wire welding method according to any one of claims 1 to 9, and the semiconductor device comprises a base island, an inner pin, a first wire, a second wire and a plastic package; The two ends of the first wire are respectively welded and fixed on the base island and the inner pin; the two ends of the second wire are respectively welded and fixed on 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 package is wrapped and arranged on the outside of the first wire and the second wire; 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 first wire and the second wire are deflected to both sides of the central axis respectively, and the central axis is a straight line formed by extending the intersection of the two wires to both sides of the base island and the inner pin; the first wire is rotated clockwise by a first angle to coincide with the separation line, and the second wire is rotated counterclockwise by a second angle to coincide with the separation line, and the separation line is a straight line that separates the gap between the base island and the inner pin and is perpendicular to the central axis; the first angle and the second angle are equal and are both 45°≤ and <90°; the second wire is located at the intersection close to the direction of the plastic packaging material input; The first conductive line is composed of a first vertical segment, a first line arc and a first inclined segment; the first line arc connects the first vertical segment and the first inclined segment; The end of the first vertical section is fixed to a welding seat formed by a flat welding ball, and the end of the first inclined section is fixed to a fishtail welding point; The second conductive line is composed of a second vertical segment, a second line arc and a second inclined segment; the second line arc connects the second vertical segment and the second inclined segment; The end of the second vertical section is fixed on a welding seat formed by a flat welding ball, and the end of the second inclined section is fixed on a fishtail welding point; the angle between the second inclined section and the horizontal plane is smaller than the angle between the first inclined section and the horizontal plane; The lateral distances between the welding points at both ends of the second wire and the separation line are greater than the lateral distances between the welding points at both ends of the first wire and the separation line.

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