Semiconductor element and manufacturing method for semiconductor element

A semiconductor device with a wire structure featuring multiple bent portions addresses reliability issues by minimizing resin contact and stress, enhancing durability through strategic wire routing.

JP2024180673AActive Publication Date: 2024-12-26HAMAMATSU PHOTONICS KK
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Patent Information

Application Number
JP2024185320
Authority / Receiving Office
JP · JP
Patent Type
Applications
Current Assignee / Owner
Filing Date
2024-10-21
Publication Date
2024-12-26
Estimated Expiration
2040-04-30

AI Technical Summary

Technical Problem

Semiconductor devices face reliability issues due to stress on wires caused by thermal cycles of sealing resin, which is exacerbated by the amount of resin between the wire and the lead frame.

Method used

The semiconductor device employs a wire structure with multiple bent portions that guide the wire to follow the corner formed by the mounting substrate and semiconductor chip, reducing the amount of resin held and minimizing stress on the wire.

Benefits of technology

This design effectively suppresses the decrease in reliability by reducing stress on the wire during thermal cycles, while also simplifying the manufacturing process and avoiding contact with the semiconductor chip.

✦ Generated by Eureka AI based on patent content.

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Abstract

To provide a semiconductor element in which the decrease in reliability can be suppressed, and a manufacturing method for the semiconductor element.SOLUTION: A semiconductor element 1 includes a mount board 10, a semiconductor chip 20, and a wire 30. The wire 30 includes a first part 31, a first bent part 41, a second part 32, a second bent part 42, and a third part 33. The first bent part 41 exists closer to a surface 10s of the mount board 10 than to a surface 20s of the semiconductor chip 20, and is bent so that the second part 32 is guided to the surface 20s side. The second part 32 extends over the surface 20s on the opposite side of the surface 10s. The second bent part 42 is bent so that the third part 33 is guided to the surface 20s side. The third part 33 extends to the surface 20s from a position over the surface 20s on the opposite side of the surface 10s.SELECTED DRAWING: Figure 1
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Description

[Technical field]

[0001] The present invention relates to a semiconductor device and a method for manufacturing a semiconductor device. [Background technology]

[0002] Patent Document 1 describes a semiconductor device. In this semiconductor device, a pad (first bonding point) of a semiconductor chip mounted on a lead frame is connected to a lead (second bonding point) of the lead frame by a wire. The wire loop shape connected to the first bonding point and the second bonding point is trapezoidal in side view, with a neck height portion on the first bonding point side, a sloped portion on the second bonding point side, and a trapezoidal length portion (loop apex portion) between the neck height portion and the sloped portion. The trapezoidal length portion is curved to have a downwardly recessed shape. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 3189115 Summary of the Invention [Problem to be solved by the invention]

[0004] In the semiconductor device described in the above Patent Document 1, a recess is formed in the top portion of the loop of the wire by bending, thereby forming a loop that has high shape retention against external pressure.

[0005] On the other hand, there is a demand for sealing such semiconductor devices with resin. In this case, sealing resin is also placed between the wire and the lead frame (wire embraces the sealing resin). Therefore, stress caused by expansion and contraction of the sealing resin due to thermal cycles is applied to the wire. The more resin there is between the wire and the lead frame, the greater the stress applied to the wire in response to the thermal cycle, which may damage the wire and reduce its reliability.

[0006] An object of the present invention is to provide a semiconductor element and a method for manufacturing the semiconductor element, which are capable of suppressing a decrease in reliability. [Means for solving the problem]

[0007] A semiconductor device according to the present invention comprises a mounting substrate having a first surface, a semiconductor chip mounted on the first surface and having a second surface facing the opposite side to the first surface, and a wire extending from a first bonding point on the first surface to a second bonding point on the second surface and connecting the first bonding point and the second bonding point to electrically connect the mounting substrate and the semiconductor chip, the wire including a first portion, a first bent portion, a second portion, a second bent portion, and a third portion arranged in this order from the first bonding point to the second bonding point, the first portion being a When viewed from a first direction along the first surface and the second surface, the first bent portion is located closer to the first surface than the second surface when viewed from the first direction and is bent so as to lead the second portion toward the second surface, and the second portion extends beyond the second surface on the opposite side to the first surface when viewed from the first direction, and the second bent portion is bent so as to lead the third portion toward the second surface, and the third portion extends from a position beyond the second surface on the opposite side to the first surface toward the second surface and is joined to the second joining point.

[0008] In this semiconductor element, a wire is provided for electrically connecting the mounting substrate and the semiconductor chip mounted on the mounting substrate. The wire connects a first joint on a first surface of the mounting substrate on which the semiconductor chip is mounted and a second joint on a second surface of the semiconductor chip. The wire includes a first portion, a first bent portion, a second portion, a second bent portion, and a third portion, which are arranged in order from the first joint to the second joint (from the mounting substrate to the semiconductor chip). The first portion is a portion of the wire that extends from the first joint and is located on the first surface side of the second surface (e.g., below the second surface). The third portion is a portion of the wire that is joined to the second joint and is located at a position beyond the second surface on the opposite side to the first surface (e.g., above the second surface). The second portion is a portion between the first portion and the third portion, and extends from a position on the first surface side beyond the second surface.

[0009] According to this structure, when the semiconductor element is resin-sealed, the sealing resin is disposed between the wire and the mounting substrate. In contrast, in this wire, the first bent portion between the first portion and the second portion is located closer to the first surface than the second surface, and is bent so as to lead the second portion to the second surface. That is, compared to a case where the first bent portion is not present, the wire extends (i.e., the first portion) toward the first surface before reaching the first bent portion, and extends (i.e., the second portion) beyond the second surface after reaching the first bent portion. That is, compared to a case where the first bent portion is not present, the wire extends so as to follow the corner formed by the mounting substrate and the semiconductor chip. As a result, the amount of resin that the wire holds when the semiconductor element is resin-sealed is reduced. Therefore, according to this semiconductor element, it is possible to reduce the stress applied to the wire in response to thermal cycles and suppress a decrease in reliability.

[0010] In this semiconductor element, the wire is bent at a second bend between the second and third portions at a position beyond the second surface, and the third portion is led to the second surface side. The third portion is then extended from the position beyond the second surface toward the second surface and joined to the second joint point. This prevents the wire from coming into contact with the corner of the semiconductor chip, compared to a case where there is no second bend and no third portion, and the second portion extends from the first surface side and is directly joined to the second joint point. This further suppresses a decrease in reliability.

[0011] In the semiconductor element according to the present invention, the first bent portion may be located closer to the first bonding point than the center of the wire in the extending direction. In this case, the first bent portion is formed at a position relatively far from the semiconductor chip. As a result, when forming the first bent portion, the holder (capillary) that holds the wire is prevented from coming into contact with the semiconductor chip.

[0012] In the semiconductor element according to the present invention, the first bent portion may be located on the second bonding point side from the center of the wire in the extending direction. In this case, the first bent portion is formed at a position relatively close to the semiconductor chip. As a result, the portion (first portion) of the wire extending to the first surface side is secured to be relatively long, and the amount of resin held by the wire is further reduced. In other words, the stress applied to the wire can be reliably reduced, and a decrease in reliability can be reliably suppressed.

[0013] In the semiconductor element according to the present invention, the wire may include a fourth portion extending to connect the first bent portion and the second portion. In this case, the height of the semiconductor chip from the first surface can be secured by at least the two portions, the second portion and the fourth portion, and therefore abrupt bending that is likely to cause stress concentration is not required. This makes it possible to more reliably suppress a decrease in reliability.

[0014] In the semiconductor element according to the present invention, the wire may extend obliquely with respect to the outer edge of the semiconductor chip when viewed from a second direction intersecting the second surface. In this case, it is easier to ensure a long wire length (the distance between the first and second bonding points) compared to when the wire is perpendicular to the outer edge of the semiconductor chip. As a result, it is easier to realize the above-mentioned structure of the wire including multiple portions and multiple bends.

[0015] The semiconductor element manufacturing method of the present invention is a semiconductor element manufacturing method for manufacturing the above-mentioned semiconductor element, and includes a first step of preparing a mounting substrate, a semiconductor chip mounted on a first surface of the mounting substrate, and at least a base material for a wire; a second step after the first step of moving a capillary holding the base material to a first joint point and joining the tip of the base material protruding from the capillary to the first joint point; a third step after the second step of moving the capillary while directing the base material from the capillary to form at least a first portion, a first bent portion, a second portion, a second bent portion, and a third portion arranged in sequence; and a fourth step after the third step of moving the capillary to the second joint point and joining the base material to the second joint point, thereby forming a wire extending from the first joint point to the second joint point.

[0016] According to this manufacturing method, the above-mentioned semiconductor element is manufactured, that is, a semiconductor element capable of suppressing a decrease in reliability is obtained.

[0017] The semiconductor device manufacturing method according to the present invention includes a fifth step of moving the capillary to a second bonding point after the first step and before the second step, bonding the tip of the base material protruding from the capillary to the second bonding point, and then cutting the tip to form a bond part at the second bonding point, and in the fourth step, the base material may be bonded to the second bonding point via the bond part. In this case, when the tip of the base material protruding from the capillary is bonded to the second bonding point after each part of the wire is formed, the bond part already formed at the second bonding point is interposed, so that impact on the semiconductor chip side is reduced. In particular, the bond part is formed using the capillary and base material for forming each part of the wire, so that the process is simplified. Effect of the Invention

[0018] According to the present invention, it is possible to provide a semiconductor element and a method for manufacturing a semiconductor element that are capable of suppressing a decrease in reliability. [Brief description of the drawings]

[0019] [Figure 1] FIG. 1 is a diagram showing a semiconductor device according to an embodiment. [Diagram 2] FIG. 2 is a photograph showing an example of the semiconductor element shown in FIG. [Diagram 3] FIG. 3 is a schematic cross-sectional view showing a process of a semiconductor device manufacturing method for manufacturing the semiconductor device shown in FIG. [Figure 4] FIG. 4 is a schematic cross-sectional view showing a process of a semiconductor device manufacturing method for manufacturing the semiconductor device shown in FIG. [Diagram 5] FIG. 5 is a schematic cross-sectional view showing a process of a semiconductor device manufacturing method for manufacturing the semiconductor device shown in FIG. [Figure 6] FIG. 6 is a diagram showing a semiconductor device according to a first modified example. [Figure 7] FIG. 7 is a diagram showing a semiconductor device according to a second modified example. [Figure 8] FIG. 8 is a diagram showing a semiconductor device according to a third modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Hereinafter, an embodiment will be described in detail with reference to the drawings. In each drawing, the same or corresponding elements are denoted by the same reference numerals, and duplicated explanations may be omitted.

[0021] FIG. 1 is a diagram showing a semiconductor element according to an embodiment. FIG. 1(a) is a schematic plan view, and FIG. 1(b) is a schematic cross-sectional view along line Ib-Ib in FIG. 1(a). FIG. 2 is a photograph showing an example of the semiconductor element shown in FIG. 1. As shown in FIGS. 1 and 2, the semiconductor element 1 includes a mounting substrate 10, a semiconductor chip 20, wires 30, and a resin part M. Note that in FIG. 1(a), the resin part M is not shown.

[0022] The mounting substrate 10 includes a front surface (first surface) 10s and a back surface 10r opposite to the front surface 10s. A plurality of flat electrodes 13 are formed on the front surface 10s. As an example, each of the plurality of electrodes 13 is elongated in a direction along an outer edge 20e of a semiconductor chip 20 described later. The plurality of electrodes 13 are arranged along the outer edge 20e.

[0023] The semiconductor chip 20 is mounted on the front surface 10s. The semiconductor chip 20 may be directly disposed on the front surface 10s, or may be disposed on the front surface 10s via another member. The semiconductor chip 20 includes a front surface (second surface) 20s and a back surface 20r opposite the front surface 20s. The front surface 20s and the back surface 20r define the height T of the semiconductor chip 20 from the front surface 10s as the distance between them. The back surface 20r is a surface facing the front surface 10s side of the mounting substrate 10, and the front surface 20s is a surface facing the side opposite the front surface 10s of the mounting substrate 10. Here, at least the front surface 10s and the front surface 20s are parallel to each other.

[0024] The semiconductor chip 20 has a rectangular parallelepiped shape, for example, and has an outer edge 20e that extends linearly. The outer edge 20e is an outer edge that faces the electrode 13 side (the bond portion 51 side described later) among the outer edges of the semiconductor chip 20. The semiconductor chip 20 is, for example, a semiconductor light receiving element (a Si photodiode, for example).

[0025] A bond portion 51 is formed on the surface 10s of the mounting substrate 10, and a bond portion 52 is formed on the surface 20s of the semiconductor chip 20. The bond portion 51 is formed on the electrode 13. The bond portion 52 is formed on the electrode 21 exposed on the surface 20s side of the semiconductor chip 20, and is electrically connected to the semiconductor chip 20. As described later, the bond portions 51 and 52 are formed integrally with the wire 30 by the same material as the wire 30. Therefore, the wire 30 is bonded to the electrode 13 via the bond portion 51 on the mounting substrate 10 side, and is bonded to the electrode 21 via the bond portion 52 on the semiconductor chip 20 side. That is, the electrode 13 is the first bonding point of the wire 30, and the electrode 21 is the second bonding point of the wire 30. The outer edge 20e of the semiconductor chip 20 and the edge of the electrode 13 on the outer edge 20e side define the distance D between the semiconductor chip 20 and the electrode 13.

[0026] In the following description, a direction that intersects (is perpendicular to) the direction from the electrode 13 toward the electrode 21 (extension direction of the wire 30) and that runs along the surfaces 10s and 20s may be referred to as a first direction, and a direction that intersects (is perpendicular to) the surfaces 10s and 20s may be referred to as a second direction. The first direction is, for example, the horizontal direction, and the second direction is, for example, the vertical direction.

[0027] Furthermore, between the region on the front surface 10s of the mounting substrate 10 where the electrodes 13 are provided and the region on the front surface 10s where the semiconductor chip 20 is provided, there is no configuration such as a recess or hole that reduces the thickness of the mounting substrate 10 (the distance between the front surface 10s and the back surface 10r). Therefore, the thickness of the mounting substrate 10 is constant in the region on the front surface 10s where the electrodes 13 are provided, the region on the front surface 10s where the semiconductor chip 20 is provided, and the region therebetween. However, the thickness of the mounting substrate 10 may be made thicker in the region between the region on the front surface 10s where the electrodes 13 are provided and the region on the front surface 10s where the semiconductor chip 20 is provided than in other regions.

[0028] In addition, here, an insulating member 60 such as a resist is formed on the surface 10s between a region on the surface 10s where the electrodes 13 are provided and a region on the surface 10s where the semiconductor chip 20 is provided. The insulating member 60 is interposed between the surface 10s and the wires 30 when viewed from the first direction, and is also interposed between the semiconductor chip 20 and the electrodes 13 when viewed from the second direction.

[0029] The wire 30 extends from the electrode 13 toward the electrode 21, and connects the electrode 13 and the electrode 21 to electrically connect the mounting substrate 10 and the semiconductor chip 20. As described above, the wire 30 is joined to and integrated with the bond portion 51 on the electrode 13 and the bond portion 52 on the electrode 21. The wire 30 is made of a metal such as gold. The wire 30 includes a first portion 31, a first bent portion 41, a second portion 32, a second bent portion 42, and a third portion 33, which are arranged in this order from the electrode 13 toward the electrode 21.

[0030] Here, the first portion 31 and the second portion 32 are connected to each other via a first bent portion 41, and the second portion 32 and the third portion 33 are connected to each other via a second bent portion 42. That is, here, the wire 30 is composed of the first portion 31, the first bent portion 41, the second portion 32, the second bent portion 42, and the third portion 33. The wire 30 is joined to a bond portion 51 at the first portion 31 (joined to the electrode 13 via the bond portion 51), and is joined to a bond portion 52 at the third portion 33 (joined to the electrode 21 via the bond portion 52).

[0031] The first portion 31 is composed of a base end 31a bonded to the electrode 13 via the bond portion 51, a tip end 31c connected to the second portion 32, and a bent portion 31b connecting the base end 31a and the tip end 31c. Here, the base end 31a extends from the electrode 13 toward the opposite side (here, the upper side) of the surface 10s and reaches the bent portion 31b. The bent portion 31b is bent so as to be convex toward the opposite side of the surface 10s. The tip end 31c extends at an incline so as to approach the surface 10s as it moves away from the bent portion 31b, and reaches the second portion 32. The above-mentioned first portion 31 is located on the surface 10s side (here, below the surface 20s) relative to the surface 20s as a whole. That is, the first portion 31 is contained on the surface 10s side relative to the surface 20s.

[0032] The first bent portion 41 is located closer to the surface 10s than the surface 20s when viewed from the first direction, and is interposed between the first portion 31 and the second portion 32, and is connected to the first portion 31 and the second portion 32. The first bent portion 41 is bent so as to be convex toward the surface 10s. As a result, the first bent portion 41 converts the inclination of the wire 30 when viewed from the first direction from an inclination approaching the surface 10s toward the electrode 21 at the tip portion 31c of the first portion 31 to an inclination away from the surface 10s toward the electrode 21 at the second portion 32 described later. In other words, the first bent portion 41 is bent so as to lead the second portion 32 toward the surface 20s. The first bent portion 41 is located closer to the electrode 13 than the center of the wire 30 in the extension direction of the wire 30.

[0033] When viewed from the first direction, a part of the second portion 32 on the first bent portion 41 side is located closer to the surface 10s than the surface 20s (here, located below the surface 20s), and the remaining part on the electrode 21 side protrudes from the surface 20s on the opposite side to the surface 10s (here, located above the surface 20s). That is, the second portion 32 extends beyond the surface 20s on the opposite side to the surface 10s from the first bent portion 41. As described above, by the second portion 32 being guided to the first bent portion 41, the wire 30 is inclined so as to move away from the surface 10s toward the electrode 21.

[0034] The second bent portion 42 is located at a position protruding from the surface 20s on the opposite side to the surface 10s when viewed from the first direction (here, it is located above the surface 20s), and is interposed between the second portion 32 and the third portion 33, and is connected to the second portion 32 and the third portion 33. The second bent portion 42 is bent so as to be convex on the opposite side to the surfaces 10s, 20s. As a result, the second bent portion 42 converts the inclination of the wire 30 when viewed from the first direction from an inclination in the second portion that moves away from the surface 10s toward the electrode 21 to an inclination in the third portion 33 that moves closer to the surface 20s toward the electrode 21, which will be described later. In other words, the second bent portion 42 is bent so as to lead the third portion 33 to the surface 20s side. The second bent portion 42 is located closer to the electrode 21 than the center of the wire 30 in the extension direction of the wire 30.

[0035] The third portion 33 protrudes from the surface 20s to the side opposite the surface 10s when viewed from the first direction (here, it is located above the surface 20s). That is, the third portion 33 extends from a position beyond the surface 20s on the side opposite the surface 10s when viewed from the first direction toward the surface 20s, and is joined to the bond portion 52 (electrode 21). As described above, by the third portion 33 being guided to the second bent portion 42, the wire 30 is inclined so as to approach the surface 20s as it approaches the electrode 21.

[0036] As a result of the above, wire 30 as a whole is bent so as to be convex toward surface 10s at first bend 41, and is bent so as to be convex toward the opposite side of surfaces 10s, 20s at second bend 42, so that it extends in an M shape from electrode 13 to electrode 21.

[0037] The wires 30 extend obliquely (inclined with respect to a line perpendicular to the outer edge 20e) of the semiconductor chip 20 when viewed from a second direction intersecting the surfaces 10s and 20s (in FIG. 1(a)). However, the wires 30 may extend parallel to a line perpendicular to the outer edge 20e of the semiconductor chip 20 when viewed from the second direction.

[0038] The resin part M is provided on the surface 10s beyond the top surface (surface 20s) of the semiconductor chip 20. As a result, the semiconductor chip 20 and the wires 30 are entirely sealed by the resin part M. The material of the resin part M is, for example, silicone or epoxy.

[0039] Next, a method for manufacturing the semiconductor element 1 will be described. Figures 3 to 5 are schematic cross-sectional views showing one step of a semiconductor element manufacturing method for manufacturing the semiconductor element shown in Figure 1. In this manufacturing method, as shown in Figure 3(a), first, a mounting substrate 10, a semiconductor chip 20 mounted on a surface 10s of the mounting substrate 10, and at least a base material 30A for the wires 30 are prepared (step S101, first step). The base material 30A is formed into a wire shape from a metal such as gold. The base material 30A is held (inserted) in a capillary C provided in a wire bonding device.

[0040] 3(a) to 3(c), the capillary C is moved to the electrode 21 as the second joining point, and the tip 30Aa of the base material 30A protruding from the capillary C is joined to the electrode 21, and then the tip 30Aa is cut to form a bond portion 52 on the electrode 21 (step S102, fifth step). More specifically, in this step S102, first, the tip 30Aa of the base material 30A protruding from the capillary C is melted to form a wire ball. Next, the wire ball is pressed against the electrode 21 while applying heat or ultrasonic waves. As a result, the bond portion 52 is formed from the wire ball. Thereafter, the bond portion 52 is cut off from the base material 30A.

[0041] In the next step, as shown in (a) and (b) of FIG. 4, the capillary C holding the base material 30A is moved to a position above the electrode 13, and a new tip 30Aa of the base material 30A protruding from the capillary C is bonded to the electrode 13 as a first bonding point (step S103, second step). More specifically, in this step S103, first, the tip 30Aa of the base material 30A protruding from the capillary C is melted to form a wire ball. Then, the wire ball is pressed against the electrode 13 while applying heat or ultrasonic waves. As a result, a bond portion 51 is formed as shown in (c) of FIG. 4, and ball bonding is performed.

[0042] Next, as shown in Figure 4 (c) and Figures 5 (a) to (c), while the base material 30A is being drawn out from the capillary C and while the base material 30A is being shaped, the capillary C is moved to form a first portion 31, a first bent portion 41, a second portion 32, a second bent portion 42, and a third portion 33 arranged in sequence (step S104, third step).

[0043] 5(c), the capillary C is moved to a position above the electrode 21, and the base material 30A is bonded to the electrode 21 to form the wire 30 extending from the electrode 13 to the electrode 21 (step S105, fourth step). More specifically, the base material 30A is pressed against the bond portion 52 with the edge portion of the tip of the capillary C, and the base material 30A is bonded to the bond portion 52 by applying heat or ultrasonic waves, and then the base material 30A is cut (stitched). This completes the stitch bonding. Thereafter, a resin portion M is provided to obtain the semiconductor element 1.

[0044] As described above, the semiconductor element is provided with wires 30 for electrically connecting the mounting substrate 10 and the semiconductor chip 20 mounted on the mounting substrate 10. The wires 30 connect the electrodes 13 on the surface 10s of the mounting substrate 10 on which the semiconductor chip 20 is mounted, to the electrodes 21 on the surface 20s of the semiconductor chip 20. The wires 30 include a first portion 31, a first bent portion 41, a second portion 32, a second bent portion 42, and a third portion 33, which are arranged in this order from the electrode 13 toward the electrode 21 (from the mounting substrate 10 toward the semiconductor chip 20).

[0045] The first portion 31 is a portion of the wire 30 that extends from the electrode 13 (bond portion 51) and is located on the surface 10s side of the surface 20s (e.g., below the surface 20s). The third portion 33 is a portion of the wire 30 that is bonded to the electrode 21 (bond portion 52) and is located at a position beyond the surface 20s on the opposite side to the surface 10s (e.g., above the surface 20s). The second portion 32 is a portion between the first portion 31 and the third portion 33 and extends from a position on the surface 10s side beyond the surface 20s.

[0046] According to such a structure, the resin of the resin part M is disposed between the wire 30 and the mounting substrate 10. In contrast, in the wire 30, the first bent portion 41 between the first portion 31 and the second portion 32 is located closer to the surface 10s than the surface 20s, and is bent so as to lead the second portion 32 to the surface 20s. That is, compared to a case where the first bent portion 41 is not present, the wire 30 is extended (i.e., the first portion 31) toward the surface 10s before reaching the first bent portion 41, and is extended (i.e., the second portion 32) beyond the surface 20s after reaching the first bent portion 41. That is, compared to a case where the first bent portion 41 is not present, the wire 30 is extended so as to follow the corner formed by the mounting substrate 10 and the semiconductor chip 20. As a result, the amount of resin held by the wire 30 is reduced. Therefore, according to the semiconductor element 1, it is possible to reduce the stress applied to the wire 30 in response to the thermal cycle and suppress a decrease in reliability.

[0047] In the semiconductor element 1, the wire 30 is bent at a second bent portion 42 between the second portion 32 and the third portion 33 at a position beyond the surface 20s, and the third portion 33 is led to the surface 20s side. Then, the third portion 33 is extended from the position beyond the surface 20s toward the surface 20s and joined to the electrode 21 (bond portion 52). Therefore, compared to a case where the second bent portion 42 and the third portion 33 are not present and the second portion 32 extends from the surface 10s side and is directly joined to the electrode 21 (bond portion 52), the wire 30 is prevented from contacting the corner portion of the semiconductor chip 20. Therefore, a decrease in reliability can be further suppressed.

[0048] Furthermore, in the semiconductor element 1, the first bent portion 41 is located closer to the electrode 13 than the center of the extension direction of the wire 30. Therefore, the first bent portion 41 is formed at a position relatively far from the semiconductor chip 20. As a result, when forming the first bent portion 41 as shown in FIG. 5(a), for example, a holder (for example, the above-mentioned capillary C) that holds the wire 30 is prevented from coming into contact with the semiconductor chip 20.

[0049] Furthermore, in the semiconductor element 1, the wire 30 extends obliquely with respect to the outer edge 20e of the semiconductor chip 20 when viewed from a second direction intersecting the surfaces 10s, 20s. Therefore, it is easier to ensure that the length of the wire 30 is long compared to when the wire 30 is perpendicular to the outer edge 20e of the semiconductor chip 20. As a result, it is easier to realize the above-mentioned structure of the wire 30 including multiple portions and multiple bent portions.

[0050] In the semiconductor element 1, an insulating member 60 such as a resist is formed on the surface 10s between the region on the surface 10s where the electrodes 13 are provided and the region on the surface 10s where the semiconductor chip 20 is provided. The insulating member 60 can be used for purposes such as forming a pattern on the mounting substrate 10 and insulating between wiring on the surface 10s, but by being interposed between the surface 10s and the wire 30, it also contributes to reducing the amount of resin held by the wire 30. Therefore, in the semiconductor element 1, a decrease in reliability is more reliably suppressed.

[0051] Moreover, according to the semiconductor element manufacturing method of this embodiment, the above-mentioned semiconductor element 1 is manufactured. That is, a semiconductor element capable of suppressing a decrease in reliability is obtained. In particular, the semiconductor element manufacturing method of this embodiment includes a step S102, which is performed after step S101 and before step S103, of moving the capillary C to the electrode 21, joining the tip 30Aa of the base material 30A protruding from the capillary C to the electrode 21, and then cutting the tip 30Aa to form a bond portion 52 on the electrode 21. At this time, in step S105, the base material 30A is joined to the electrode 21 via the bond portion 52. As a result, when the tip of the base material 30A protruding from the capillary C is joined to the electrode 21 after each part of the wire 30 is formed, the bond portion 52 already formed on the electrode 21 is interposed, so that the impact on the semiconductor chip 20 side is reduced. In particular, since the bond portion 52 is formed using the capillary C and the base material 30A for forming each portion of the wire 30, the process can be simplified.

[0052] The above embodiment has been described as one form of the present invention. Therefore, the present invention is not limited to the above embodiment, and may be modified as desired. As an example, the semiconductor element 1 according to the above embodiment may be modified according to the distance D between the semiconductor chip 20 and the electrode 13, or the height T of the semiconductor chip 20. Next, modified examples of the semiconductor element 1 according to the above embodiment will be described. [First Modification]

[0053] FIG. 6 is a diagram showing a semiconductor element according to a first modified example. FIG. 6(a) is a schematic cross-sectional view, and FIG. 6(b) is an enlarged photograph. In the example shown in FIG. 6, the distance D between the electrode 13 and the semiconductor chip 20 is made larger than that in FIG. 1. In such a case, the length of the first portion 31 extending toward the surface 10s side from the surface 20s can be relatively increased by positioning the first bent portion 41 on the semiconductor chip 20 side. As a result, the first bent portion 41 is positioned toward the electrode 21 side from the center in the extending direction of the wire 30. Note that, in this case, the tip portion 31c of the first portion 31 on the second portion 32 side is extended from the bent portion 31b, so that the first bent portion 41 is positioned toward the electrode 21 side.

[0054] According to the first modified example described above, the first bent portion 41 is formed at a position relatively close to the semiconductor chip 20. As a result, the portion (first portion 31) of the wire 30 extending toward the front surface 10s is secured to be relatively long, and the amount of resin held by the wire 30 is further reduced. In other words, the stress applied to the wire 30 is reliably reduced, and deterioration of reliability can be reliably suppressed. [Second modified example]

[0055] Fig. 7 is a diagram showing a semiconductor element according to a second modified example. Fig. 7(a) is a schematic cross-sectional view, and Fig. 7(b) is an enlarged photograph. In the example of Fig. 7, the height T of the semiconductor chip 20 is made larger than that of Fig. 1. Here, a third bent portion 43 and a fourth portion 34 are interposed between the first portion 31 and the first bent portion 41. The third bent portion 43 and the fourth portion 34 are arranged in this order in the direction from the electrode 13 toward the electrode 21.

[0056] The third bent portion 43 and the fourth portion 34 are located closer to the surface 10s than the surface 20s. The third bent portion 43 is connected to the first portion 31 and the fourth portion 34. The third bent portion 43 is bent so as to be convex toward the surface 10s. That is, the third bent portion 43 is bent so as to be convex in the same direction as the first bent portion 41. As a result, the third bent portion 43 converts the inclination of the wire 30 when viewed from the first direction from an inclination approaching the surface 10s toward the electrode 21 at the tip portion 31c of the first portion 31 to an inclination away from the surface 10s toward the electrode 21 at the fourth portion 34 described later. In other words, the third bent portion 43 is bent so as to lead the fourth portion 34 toward the surface 20s.

[0057] The fourth portion 34 extends at an angle away from the surface 10s toward the electrode 21 so as to connect the first portion 31 and the first bent portion 41. Here, the first bent portion 41 is positioned on the electrode 21 side by the length of the fourth portion 34, so that the first bent portion 41 is positioned on the electrode 21 side relative to the center in the extension direction of the wire 30. However, the first bent portion 41 may be positioned at the center in the extension direction of the wire 30 or on the electrode 13 side relative to the center, depending on the length of the fourth portion 34.

[0058] In this example, the inclination direction of the wire 30 does not change before and after the first bent portion 41 (i.e., the fourth portion 34 and the second portion 32). That is, here, the first bent portion 41 is bent so as to be convex toward the surface 10s so that the inclination away from the surface 10s toward the electrode 21 at the fourth portion 34 is also maintained at the second portion 32.

[0059] According to the second modification, the height T of the semiconductor chip 20 from the surface 10s can be ensured by at least the second portion 32 and the fourth portion 34, eliminating the need for abrupt bending that is likely to cause stress concentration. This makes it possible to more reliably prevent a decrease in reliability. [Third Modification]

[0060] Fig. 8 is a diagram showing a semiconductor device according to a third modified example. Fig. 8(a) is a schematic cross-sectional view, and Fig. 8(b) is an enlarged photograph. In the example shown in Fig. 8, the bending angle of the bent portion 31b of the first portion 31 is made larger than that in the example of Fig. 1. More specifically, the bent portion 31b is bent at a right angle so as to connect the base end portion 31a extending perpendicularly to the surface 10s with the tip end portion 31c extending parallel to the surface 10s.

[0061] According to the third modified example, the first portion 31 extends from the electrode 13 along the surface 10s, which can further reduce the amount of resin held by the wire 30. That is, the stress applied to the wire 30 can be reliably reduced, and deterioration of reliability can be reliably suppressed.

[0062] In the above semiconductor element 1, an example has been described in which the bond portion 52 is provided on the surface 20s of the semiconductor chip 20, and the wire 30 is bonded to this bond portion 52. Such a bond portion 52 can be installed, for example, from the same material as the wire 30 prior to the provision of the wire 30, as described above. However, in the semiconductor element 1, the bond portion 52 is not essential, and the wire 30 may be directly bonded to the semiconductor chip 20. Even when the bond portion 52 is provided, the bond portion 52 may be provided separately by a device different from the wire bonding device for the wire 30.

[0063] Furthermore, the positions of the bond portions 51, 52 can be set arbitrarily in the semiconductor element 1. Therefore, when viewed from the second direction, the inclination of the wire 30 with respect to the outer edge 20e of the semiconductor chip 20 can also be set arbitrarily depending on the positional relationship of the bond portions 51, 52 (electrodes 13, 21). [Explanation of symbols]

[0064] 1...semiconductor element, 10...mounting substrate, 10s...surface (first surface), 13...electrode (first bonding point), 20...semiconductor chip, 20s...surface (second surface), 21...electrode (second bonding point), 30...wire, 31...first part, 32...second part, 33...third part, 34...fourth part, 41...first bend, 42...second bend, 51...bond portion, 52...bond portion.

Claims

1. a mounting substrate having a first surface; a semiconductor chip mounted on the first surface and having a second surface facing the opposite side to the first surface; a wire extending from a first bonding point on the first surface to a second bonding point on the second surface and connecting the first bonding point and the second bonding point, thereby electrically connecting the mounting substrate and the semiconductor chip; Equipped with the wire includes a first portion, a first bent portion, a second portion, a second bent portion, and a third portion, which are arranged in order from the first junction to the second junction; the first portion is located closer to the first surface than the second surface when viewed from a first direction along the first surface and the second surface, the first bent portion is located closer to the first surface than the second surface when viewed from the first direction, and is bent so as to guide the second portion toward the second surface, the second portion extends beyond the second surface on a side opposite to the first surface when viewed from the first direction, the second bent portion is bent so as to guide the third portion toward the second surface side, the third portion extends from a position beyond the second surface on a side opposite to the first surface as viewed from the first direction toward the second surface and is joined to the second joining point; an insulating member is formed on the first surface between the first bonding point and the semiconductor chip; Semiconductor element.

2. The first bent portion is located closer to the first joint point than the center of the wire in an extending direction. The semiconductor device according to claim 1 .

3. The first bent portion is located on the second joint side from the center of the wire in an extending direction. The semiconductor device according to claim 1 .

4. the wire includes a fourth portion extending to connect the first portion and the first bent portion; The semiconductor device according to any one of claims 1 to 3.

5. the wire extends obliquely with respect to an outer edge of the semiconductor chip when viewed from a second direction intersecting the second surface; The semiconductor device according to any one of claims 1 to 4.

6. the second bonding point is provided at a position farther from the center of the semiconductor chip than the first bonding point in a direction along the first surface and the second surface and intersecting a direction in which the semiconductor chip and the first bonding point are arranged. The semiconductor device according to any one of claims 1 to 5.

7. a plurality of the first junction points, a plurality of the second junction points, and a plurality of the wires; Each of the plurality of wires connects each of the plurality of first junctions to each of the plurality of second junctions. The semiconductor device according to any one of claims 1 to 6.

8. the first bonding points are located on one side of the semiconductor chip when viewed from a second direction intersecting the second surface; The semiconductor device according to claim 7.

9. A method for manufacturing the semiconductor device according to any one of claims 1 to 8, comprising the steps of: a first step of preparing a base material for the mounting substrate, the semiconductor chip mounted on the first surface of the mounting substrate, and at least the wires; After the first step, a second step of moving the capillary holding the base material to the first joining point and joining a tip of the base material protruding from the capillary to the first joining point; a third step of, after the second step, moving the capillary while drawing out the base material from the capillary to form at least the first portion, the first bent portion, the second portion, the second bent portion, and the third portion, which are arranged in order; a fourth step of forming the wire extending from the first joint point to the second joint point by moving the capillary to the second joint point and joining the base material to the second joint point after the third step; Equipped with Semiconductor device manufacturing method.

10. a fifth step of moving the capillary to the second joining point after the first step and before the second step, joining a tip of the base material protruding from the capillary to the second joining point, and then cutting the tip to form a bond portion at the second joining point; In the fourth step, the base material is joined to the second joining point via the bond portion. The method for manufacturing a semiconductor device according to claim 9.

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