JP2015109334A - Semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To minimize the occurrence of wire removal caused by heat application in an electronic apparatus formed by performing soldering and wire bonding on a semiconductor element having a first electrode for soldering and a second electrode for wire bonding.SOLUTION: A semiconductor device comprises: a semiconductor element 40 having a first electrode 20 and a second electrode 30 on one surface 41; a terminal 50 bonded with the first electrode 20 via a tin-containing solder 80; and an Al-wire 60 bonded with the second electrode 30 by wire bonding. The second electrode 30 has a surface to which the wire 60 is bonded and which is composed of Ni/Pd/Au plating composed of a Ni plating film 32, a Pd plating film 33 and an Au plating film 34 which are sequentially laminated from the semiconductor element 40 side.

Description

  The present invention relates to a semiconductor device in which a terminal is soldered to a first electrode provided on one surface of a semiconductor element, and a bonding wire is bonded to a second electrode also provided on the same surface of the semiconductor element.

  Conventionally, as a semiconductor element having a first electrode and a second electrode on one surface, for example, there is a power element having a source electrode and a gate electrode on one surface. Usually, the first electrode and the second electrode are made of an Au (gold) plating film having a Ni (nickel) plating film as a base, ie, Ni / Au plating, on the surface of a metallized film such as an Al (aluminum) film. It is something that has been applied. A bonding wire made of Al is connected to both the electrodes.

  On the other hand, there has been proposed an electronic apparatus using a substrate having both a soldering portion to which an electronic component is soldered and a bonding land to be wire-bonded on one surface (for example, see Patent Document 1). This electronic device is manufactured by soldering an electronic component on a substrate and subsequently performing wire bonding.

JP 2010-103232 A

  In view of the recent demand for a large current in the device, the present inventor is examining a semiconductor device in which a terminal is soldered to the first electrode among the two electrodes in the semiconductor element. This is because a terminal made of Cu or the like has a larger amount of current than an Al wire. In this case, a general solder containing Sn (tin) is used as the solder.

  That is, in this case, the first electrode for soldering and the second electrode for wire bonding exist on one surface of the semiconductor element. Such a semiconductor device is manufactured by soldering a terminal with a first electrode and then wire bonding with an Al wire with a second electrode, as in Patent Document 1. .

  Here, in the manufacture of such a semiconductor device, in addition to the heating at the time of soldering described above, further, after soldering, heating by frictional heat at the time of wire bonding, and the device and other parts after wire bonding Heating is performed for the connection.

  Therefore, the heating process as a post-process of these soldering causes the semiconductor element to have a high temperature (for example, 150 ° C. or more), voids are generated in the Au plating film on the surface of the second electrode, and the wire is easily peeled off. The problem arises.

  The present invention has been made in view of the above problems, and is formed by performing soldering and wire bonding on a semiconductor element having a first electrode for soldering and a second electrode for wire bonding on one side. An object of the present invention is to prevent wire peeling due to heating as much as possible.

  In order to achieve the above object, the present inventor has intensively studied and estimated the generation mechanism of the void that causes wire peeling in this type of semiconductor device as follows. This estimation mechanism will be described with reference to FIGS.

  FIG. 9 shows a schematic cross section of the surface-side portion of the second electrode 30 for wire bonding, where (a) is a state before the wire 60 is in contact, (b) is a state when the wire 60 is in contact, (c ) Shows a state in which (b) is further heated. The second electrode 30 is a typical one in which the surface of an Al film 31 as a metallized film is subjected to an Au plating film 34 with a Ni plating film 32 as a base, that is, Ni / Au plating. FIG. 10 schematically shows the vicinity of the surface of the second electrode 30 further enlarged.

  First, before wire bonding, a terminal is soldered to the first electrode for soldering (not shown) on the semiconductor element with solder containing Sn. Then, as shown in FIGS. 10A and 10B, Sn (tin) 1 (dot hatching in the figure) is applied from the solder on the first electrode to the second electrode 30 by the reflow of the solder. ) Are scattered and adhere to the surface of the Au plating film 34.

  Then, as shown in FIG. 10C, Sn1 diffuses into the Au plating film 34 by the heat of the solder reflow and the like, while Ni (nickel) 3 (see FIG. (Indicated by white circles) diffuses to the Au plating film 34 side.

Then, Sn1 and Ni3 react in the Au plating film 34, and as shown in FIG. 10C, a Sn—Ni alloy (for example, Ni ₃ Sn, one side in FIG. 10) 2) (shown by hatched circles).

  Then, by performing wire bonding to the second electrode 30 in this state, the wire 60 made of Al is formed on the Au plating film 34 as shown in FIGS. 9B and 10D. Connected. In this state, the heating as the post-soldering process described above, that is, the heating for wire bonding and the heating for connecting other components after the wire bonding are performed on the semiconductor element.

  In the subsequent heating step, as shown in FIGS. 9C, 10E, and 10F, the Au of the Au plating film 34 and the Al of the wire 60 are mutually connected in the second electrode 30. Diffusion occurs, an Au—Al alloy layer 35 is formed between the Ni plating film 32 and the wire 60, and the Au plating film 34 becomes thinner.

  However, in the formation of the Au—Al alloy layer 35, if the Sn—Ni alloy 2 is present in the Au plating film 34, the diffusion of Au is obstructed by the Si—Ni alloy 2, and the existing portion of the Sn—Ni alloy 2 is present. In this case, the diffusion is slow and the diffusion is fast in the non-existing portion, so that the diffusion rate of Au becomes non-uniform. As a result, as shown in FIGS. 10E and 10F, a Kirkendall void B is generated in the portion of the Sn—Ni alloy 2 in the second electrode 30, and this void B grows. .

  For this reason, in the second electrode 30, the strength is reduced at the void B, and the wire 60 is easily peeled off. The above is the presumed mechanism by examination of this inventor. This is confirmed by microscopic observation and elemental analysis.

  Therefore, in view of this mechanism, the present inventor, at the time of solder reflow, diffused Sn in the Au plating film surface of the second electrode into the Au plating film, and Sn—Ni alloy in the Au plating film. I thought it would be good to suppress the formation of. The present invention has been created by focusing on this point.

  That is, in the first aspect of the invention, the semiconductor element (40) having the first electrode (20) for soldering and the second electrode (30) for wire bonding on one surface (41), and the first A terminal (50) joined to one electrode via a solder (80) containing tin; and a wire (60) made of aluminum joined to the second electrode by wire bonding. The second electrode has a Ni / Pd / Au layer in which the surface to which the wire is bonded is formed by sequentially laminating a Ni plating film (32), a Pd plating film (33), and an Au plating film (34) from the semiconductor element side. It is characterized by being formed by plating (see, for example, FIGS. 1 and 2).

  According to this, the diffusion of Ni to the surface side in the second electrode is inhibited and prevented by the Pd plating film. Therefore, Sn in the solder adhered to the second electrode surface does not react with Ni to produce an alloy. Therefore, according to the present invention, the generation of voids in the Au plating film of the second electrode can be prevented, so that wire peeling due to heating can be prevented as much as possible.

  Further studies were made based on the above mechanism, and the semiconductor device according to claim 3 was created. That is, in the invention according to claim 3, the semiconductor element (40) having the first electrode (20) for soldering and the second electrode (30) for wire bonding on one surface (41), the first A terminal (50) joined to one electrode via a solder (80) containing tin; and a wire (60) made of aluminum joined to the second electrode by wire bonding. The second electrode is made of an Al film (31) that does not contain Ni, and the surface to which the wire is bonded is a surface made of Al without plating. (See, for example, FIGS. 3-5).

  According to this, since the surface of the second electrode and the wire are Al, bondability of wire bonding is ensured. In addition, since the surface of the second electrode is Al without Ni, Sn in the solder attached to the surface of the second electrode does not react with Ni to form an alloy in the first place. The second electrode also has no Au plating film as a void generation site. Therefore, according to the present invention, the generation of Kirkendall voids in the second electrode can be prevented, so that wire peeling due to heating can be prevented as much as possible.

  Further studies were made based on the above mechanism, and the semiconductor device according to claim 4 was created. That is, in the invention according to claim 4, the semiconductor element (40) having the first electrode (20) for soldering and the second electrode (30) for wire bonding on one surface (41), and the first A terminal (50) joined to one electrode via a solder (80) containing tin; and a wire (60) made of aluminum joined to the second electrode by wire bonding. The second electrode is characterized in that the surface to which the wire is bonded is composed of a Ni plating film (32) (see, for example, FIGS. 6 to 8).

  According to this, since the surface of the second electrode and the wire are Ni and Al, the compatibility of the bonding is good and the bonding property of the wire bonding is ensured. Moreover, since the surface of the second electrode is a Ni plating film and there is no conventional Au plating film thereon, Sn in the solder attached to the surface of the second electrode reacts with Ni to form an alloy. The generation of the above-mentioned Kirkendall void can be prevented even if the is generated. Therefore, according to the present invention, it is possible to prevent wire peeling due to heating as much as possible.

  In addition, the code | symbol in the bracket | parenthesis of each means described in the claim and this column is an example which shows a corresponding relationship with the specific means as described in embodiment mentioned later.

It is a schematic sectional drawing which shows the principal part of the semiconductor device concerning 1st Embodiment of this invention. It is a schematic sectional drawing which shows the principal part of the semiconductor device concerning 2nd Embodiment of this invention. It is a schematic sectional drawing which shows the principal part of the semiconductor device concerning 3rd Embodiment of this invention. It is a schematic sectional drawing which shows the principal part of the semiconductor device concerning 4th Embodiment of this invention. It is a schematic sectional drawing which shows the principal part of the semiconductor device concerning 5th Embodiment of this invention. It is a schematic sectional drawing which shows the principal part of the semiconductor device concerning 6th Embodiment of this invention. It is a schematic sectional drawing which shows the principal part of the semiconductor device concerning 7th Embodiment of this invention. It is a schematic sectional drawing which shows the principal part of the semiconductor device concerning 8th Embodiment of this invention. It is a figure which shows the presumed mechanism of wire peeling generation | occurrence | production by the inventors' trial manufacture examination. It is a figure which shows typically the detail of the mechanism shown by FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other are given the same reference numerals in the drawings in order to simplify the description.

(First embodiment)
The semiconductor device S1 according to the first embodiment of the present invention will be described with reference to FIG. Here, in FIG. 1 and the following FIGS. 2 to 8, for the sake of clarity, the Al films 21 and 31 and the plating films 22 to 24 and 32 are formed with respect to the thickness of the semiconductor element 40 (for example, 150 μm). The thickness of ~ 34 is exaggerated.

  Further, in FIG. 1, Sn (tin) scattered from the solder 80 is denoted by reference numeral 1 for the sake of explanation. However, in reality, this Sn1 is generated during soldering of the terminal 50, which is a manufacturing process of the semiconductor device, in the present embodiment and each of the following embodiments, and in the semiconductor device in a completed state. It does not occur. The scattered Sn1 is exaggerated, and is actually considered to be scattered and adhered from the first electrode 20 to the second electrode 30 at an ion level size.

  The semiconductor device S1 of this embodiment is mounted on a vehicle such as an automobile, and is applied as a device for driving various electronic devices for the vehicle. The semiconductor device S1 roughly includes a substrate 10, a semiconductor element 40 mounted on the substrate 10 and having a first electrode 20 for soldering and a second electrode 30 for wire bonding on one surface, and a first A terminal 50 soldered to the second electrode, and a wire 60 made of Al joined to the second electrode by wire bonding.

  Here, the semiconductor element 40, the terminal 50, and the wire 60 positioned on the substrate 10 may be sealed with a mold resin (not shown) as necessary. Of course, if not required, the molding resin may be omitted. The mounting component on the substrate 10 may be only the semiconductor element 40, but other mounting components (not shown) other than the semiconductor element 40 may be mounted on the substrate 10.

  First, the substrate 10 may be any substrate that can be mechanically and electrically connected to the semiconductor element 40. For example, examples of the substrate 10 include a lead frame made of a conductive metal such as Cu or 42 alloy, a ceramic substrate made of alumina, or a printed board.

  The semiconductor element 40 has the first electrode 20 for soldering and the second electrode 30 for wire bonding on the same surface 41, and is configured as a semiconductor chip such as a silicon semiconductor.

  The semiconductor element 40 is bonded to the substrate 10 via a die bond material 70. The die bond material 70 is not particularly limited, and examples thereof include solder, a conductive adhesive, and a nonconductive adhesive.

  Such a semiconductor element 40 typically includes a power element such as an IGBT (Insulated Gate Bipolar Transistor) or a MOS transistor. When the semiconductor element 40 is a power element, for example, the first electrode 20 for soldering is a source electrode of the power element, and the second electrode 30 for wire bonding is a gate electrode of the power element. Can be something.

  The first electrode 20 has an Al film 21 as a metallized film that is bonded in direct contact with a semiconductor portion (for example, Si) of the semiconductor element 40. The first electrode 20 is a Ni / Pd / Au layer in which a Ni plating film 22, a Pd (palladium) plating film 23, and an Au plating film 24 are sequentially laminated on the surface of the Al film 21 from the semiconductor element 40 side. It is configured as plated.

  The second electrode 30 is formed by Ni / Pd / Au plating in which the surface to which the wire 60 is bonded is formed by sequentially laminating a Ni plating film 32, a Pd plating film 33, and an Au plating film 34 from the semiconductor element 40 side. It is configured.

  That is, the second electrode 30 of the present embodiment has a film configuration similar to that of the first electrode 20, and in order from the one surface 41 side of the semiconductor element 40, an Al film 31, a Ni plating film 32, and Pd as a metallized film. The plating film 33 and the Au plating film 34 are laminated.

  The semiconductor element 40 having both the electrodes 20 and 30 of the first electrode 20 and the second electrode 30 is formed by a normal semiconductor process or film formation technique. Specifically, first, Al films 21 and 31 as metallized films in the electrodes 20 and 30 are formed on one surface 41 of the semiconductor element 40 formed by a semiconductor process by physical vapor deposition (PVD) or chemical vapor deposition (CVD). ) Or the like.

  Thereafter, Ni plating films 22 and 32, Pd plating films 23 and 33, and Au plating films 24 and 34 are sequentially formed on the Al films 21 and 31 by using a known plating method such as electroplating or electroless plating. Will form. Thereby, the semiconductor element 40 having both the electrodes 20 and 30 is completed.

  Here, as will be described later, the Pd plating film 33 in the second electrode 30 is formed by reacting the Ni plating film 32 in the second electrode 30 with the Sn 80 of the solder 80 attached to the second electrode 30. It functions as a barrier film (barrier film) that prevents Ni in the Ni plating film 32 from diffusing up to the Au plating film 34 so as not to form a Ni alloy.

  In view of this point, the thickness of each film in the electrodes 20 and 30 is not limited, but can be as follows, for example. Al film 21, 31: several μm, Ni plating film 22, 32: 0.5 μm to several μm, Pd plating film 23, 33: 2 nm to 100 nm, Au plating film 24, 34: 3 nm to 50 nm.

  The terminal 50 has a typical elongated plate shape, and one end side in the longitudinal direction is soldered and joined to the surface of the first electrode 20 of the semiconductor element 40. The other end side (not shown) of the terminal 50 is connected to, for example, an appropriate place on the board 10 or other mounting parts (not shown) mounted on the board 10. The terminal 50 is typically made of a metal having excellent conductivity such as Cu or Cu alloy.

  Here, examples of the solder 80 for soldering the terminal 50 include eutectic solder containing Sn, Pb-free solder, and the like. Specific examples include Sn-Ag solder and Sn-Cu solder.

  The wire 60 is bonded by a typical method for bonding an Al wire, that is, wedge bonding in which ultrasonic power is applied to perform bonding. Here, one end side of the wire 60 is joined to the second electrode 30, and the other end side (not shown) of the wire 60 is, for example, a suitable place on the substrate 10, or another component (not shown) mounted on the substrate 10. It is connected to the.

  Such a semiconductor device S1 is manufactured as follows. First, the semiconductor element 40 having the first electrode 20 and the second electrode 30 is prepared, and the semiconductor element 40 is mounted on the substrate 10 via the die bond material 70 and bonded (element mounting step).

  Next, the terminal 50 is brought into contact with the first electrode 20 of the semiconductor element 40 through the solder 80, and the solder reflow is performed by heating, whereby the first electrode 20 and the terminal 50 are joined by soldering. (Soldering process).

  Thereafter, the wire 60 is bonded to the second electrode 30 by performing ultrasonic wire bonding (wire bonding step). Thereafter, the semiconductor device S1 of this embodiment is completed by connecting other components on the substrate 10 or sealing with a mold resin as necessary.

  By the way, in manufacturing the semiconductor device S1 in which wire bonding is performed after soldering as in the present embodiment, the first electrode is soldered as shown in FIG. 1 when the terminal 50 is soldered to the first electrode 20. Sn1 scatters from the solder 80 on 20 and adheres to the surface of the second electrode 30.

  After this soldering, the semiconductor element 40 is heated by frictional heat at the time of wire bonding to the second electrode 30, heat at the time of connection to other components after wire bonding, or the like. That is, as described in FIGS. 9 and 10, the semiconductor element 40 is heated as a post-soldering process of the terminal 50.

  Conventionally, as shown in FIG. 9 and FIG. 10 described above, in the second electrode 30 to which the wire 60 is bonded by heating as a subsequent process, Kirkendall made of Sn—Ni alloy 2 in the Au plating 34 film. Void B is generated.

  However, according to the present embodiment, in the second electrode 30, the diffusion of Ni from the Ni plating film 32 to the surface side is inhibited and prevented by the Pd plating film 33. That is, the Pd plating film 33 functions as the Ni diffusion barrier film (barrier film) as described above.

  Therefore, Sn1 scattered from the solder 80 and adhering to the surface of the second electrode 30 does not react with Ni in the Au plating film 34 to generate a Sn—Ni alloy. Therefore, according to the present embodiment, it is possible to prevent the occurrence of the void B in the Au plating film 34 of the second electrode 30, and thus it is possible to prevent the wire 60 from being peeled off by heating as much as possible.

(Second Embodiment)
The semiconductor device S2 according to the second embodiment of the present invention will be described with reference to FIG. 2, focusing on differences from the first embodiment. In the present embodiment, the film configuration of the first electrode 20 for soldering is partially modified as compared with the first embodiment having the Pd plating film 33 as a barrier film.

  In the first embodiment, the first electrode 20 is formed by laminating the Al film 21, the Ni plating film 22, the Pd plating film 23, and the Au plating film 24 in this order from the one surface 41 side of the semiconductor element 40. It was. On the other hand, as shown in FIG. 2, the first electrode 20 of this embodiment is formed by laminating an Al film 21, a Ni plating film 22, and an Au plating film 24 in order from the one surface 41 side of the semiconductor element 40. It is supposed to be.

  That is, in the present embodiment, a film configuration in which the Pd plating film 23 in the first electrode 20 of the first embodiment is omitted is adopted. Both the electrodes 20 and 30 of this embodiment are formed by using the same plating method as that of the first embodiment, without applying Pd plating to the first electrode 20, and applying Pd only to the second electrode 30. It is formed by performing selective plating in which plating is performed. Specifically, the first electrode 20 is subjected to Ni / Au plating, and the second electrode 30 is subjected to Ni / Pd / Au plating.

  Also in this embodiment, since the Pd plating film 33 functions as a Ni diffusion barrier film in the second electrode 30, the formation of Sn—Ni alloy in the second electrode 30 due to the scattered Sn is prevented. And the generation of voids is prevented. Therefore, also according to this embodiment, it is possible to prevent the wire 60 from being peeled off by heating as much as possible.

(Third embodiment)
A semiconductor device S3 according to the third embodiment of the present invention will be described with reference to FIG. 3, focusing on differences from the first embodiment. In the present embodiment, the configuration of the second electrode 30 for wire bonding is modified as compared with the first embodiment.

  In the first embodiment, the second electrode 30 is formed by laminating the Al film 31, the Ni plating film 32, the Pd plating film 33, and the Au plating film 34 in this order from the one surface 41 side of the semiconductor element 40. It was. On the other hand, as shown in FIG. 3, the second electrode 30 of this embodiment is made of a single Al film 31.

  That is, in this embodiment, the film configuration is such that all of the plating films 32 to 34 in the second electrode 30 of the first embodiment are omitted. Both the electrodes 20 and 30 of this embodiment use the same plating method as that of the first embodiment, apply Ni / Pd / Au plating only to the first electrode 20, and apply the second electrode 30 to the second electrode 30. It is formed by performing selective plating in which plating is not performed.

  Specifically, the semiconductor device S3 of this embodiment is manufactured as follows. First, the Al films 21 and 31 are formed on the one surface 41 of the semiconductor element 40 by vapor deposition or the like. Then, in a state where the Al film 31 to be the second electrode 30 is masked, an Ni plating film 22, a Pd plating film 23, and an Au plating film 24 are sequentially formed on the Al film 21 in the first electrode 20. Go. Thereby, the semiconductor element 40 having both the electrodes 20 and 30 of the present embodiment is completed.

  Next, the mask on the Al film 31 to be the second electrode 30 is removed, and the semiconductor element 40 is mounted on the substrate 10 and bonded. Thereafter, the terminal 50 is soldered to the first electrode 20, and then the wire bonding to the second electrode 30 is performed. Thereby, the semiconductor device S3 of this embodiment is completed.

  As described above, the second electrode 30 of the present embodiment is made of the Al film 31 that does not contain Ni, and the surface to which the wire 60 is bonded is made of Al without being plated. Is.

  According to this, since the surface of the second electrode 30 and the wire 60 are Al, bondability of wire bonding is ensured. Further, since the surface of the second electrode 30 is Al in which Ni does not exist, Sn in the solder 80 attached to the surface of the second electrode 30 reacts with Ni to generate a Sn—Ni alloy. In the first place it disappears.

  Further, the second electrode 30 also does not have an Au plating film 34 that serves as a Sn-Ni alloy generation site and a void generation site. Therefore, according to the present embodiment, the generation of Kirkendall voids in the second electrode 30 can be prevented, and therefore the peeling of the wire 60 due to heating can be prevented as much as possible.

(Fourth embodiment)
The fourth embodiment of the present invention is obtained by partially modifying the film configuration of the first electrode 20 for soldering in the third embodiment in which the second electrode 30 is made of a single Al film 31. Therefore, the semiconductor device S4 according to the present embodiment will be described with reference to FIG. 4 focusing on differences from the third embodiment.

  In the third embodiment, the first electrode 20 is formed by laminating the Al film 21, the Ni plating film 22, the Pd plating film 23, and the Au plating film 24 in this order from the one surface 41 side of the semiconductor element 40. It was. On the other hand, as shown in FIG. 4, the first electrode 20 of this embodiment is formed by laminating an Al film 21 and a Ni plating film 22 in order from the one surface 41 side of the semiconductor element 40.

  That is, in this embodiment, the film configuration is such that the Pd plating film 23 and the Au plating film 24 in the first electrode 20 of the third embodiment are omitted. The electrodes 20 and 30 of this embodiment are selectively plated such that only the first electrode 20 is plated with Ni and the second electrode 30 is not plated in the third embodiment. Is formed.

  Specifically, the semiconductor device S4 of this embodiment is manufactured as follows. First, the Al films 21 and 31 are formed on the one surface 41 of the semiconductor element 40 by vapor deposition or the like. Then, a Ni plating film 22 is formed on the Al film 21 in the first electrode 20 in a state where the Al film 31 to be the second electrode 30 is masked. Thereby, the semiconductor element 40 having both the electrodes 20 and 30 of the present embodiment is completed.

  Next, the mask on the Al film 31 to be the second electrode 30 is removed, and the semiconductor element 40 is mounted on the substrate 10 and bonded. Thereafter, the terminal 50 is soldered to the first electrode 20, and then the wire bonding to the second electrode 30 is performed. Thereby, the semiconductor device S4 of this embodiment is completed.

  As described above, the second electrode 30 of the present embodiment is also made of the Al film 31 that does not contain Ni, and the surface to which the wire 60 is bonded is made of Al without being plated. It is supposed to be.

  Therefore, as in the third embodiment, wire bondability is ensured. At the same time, since the surface of the second electrode 30 is Al without Ni, it is possible to prevent Sn-Ni alloy formation in the second electrode 30 due to scattered Sn and generation of voids. . Therefore, according to this embodiment, it is possible to prevent the wire 60 from being peeled off by heating as much as possible.

(Fifth embodiment)
The fifth embodiment of the present invention is obtained by partially modifying the film configuration of the first electrode 20 for soldering in the third embodiment in which the second electrode 30 is made of a single Al film 31. Therefore, the semiconductor device S5 according to the present embodiment will be described with reference to FIG. 5, focusing on the differences from the third embodiment.

  In the third embodiment, the first electrode 20 is formed by laminating the Al film 21, the Ni plating film 22, the Pd plating film 23, and the Au plating film 24 in this order from the one surface 41 side of the semiconductor element 40. It was. On the other hand, as shown in FIG. 5, the first electrode 20 of this embodiment is formed by laminating an Al film 21, a Ni plating film 22, and an Au plating film 24 in order from the one surface 41 side of the semiconductor element 40. It is supposed to be.

  That is, in this embodiment, the film configuration is such that the Pd plating film 23 in the first electrode 20 of the third embodiment is omitted. Such electrodes 20 and 30 of this embodiment are selective plating in which only the first electrode 20 is subjected to Ni / Au plating and the second electrode 30 is not subjected to plating in the third embodiment. It is formed by performing.

  Specifically, the semiconductor device S5 of this embodiment is manufactured as follows. First, the Al films 21 and 31 are formed on the one surface 41 of the semiconductor element 40 by vapor deposition or the like. Then, a Ni plating film 22 and an Au plating film 24 are sequentially formed on the Al film 21 in the first electrode 20 in a state where the Al film 31 to be the second electrode 30 is masked. Thereby, the semiconductor element 40 having both the electrodes 20 and 30 of the present embodiment is completed.

  Next, the mask on the Al film 31 to be the second electrode 30 is removed, and the semiconductor element 40 is mounted on the substrate 10, the terminal 50 is soldered, and wire bonding is sequentially performed as described above. Thereby, the semiconductor device S5 of this embodiment is completed.

  As described above, the second electrode 30 of the present embodiment is also made of the Al film 31 that does not contain Ni, and the surface to which the wire 60 is bonded is made of Al without being plated. It is supposed to be. Therefore, as in the third embodiment, the bondability of wire bonding can be ensured and the peeling of the wire 60 due to heating can be prevented as much as possible.

(Sixth embodiment)
A semiconductor device S6 according to a sixth embodiment of the present invention will be described with reference to FIG. 6, focusing on differences from the first embodiment. Compared with the first embodiment, the present embodiment is a modification of the film configuration of the electrodes 20 and 30 of the first electrode 20 for soldering and the second electrode 30 for wire bonding. .

  In the first embodiment, the first electrode 20 and the second electrode 30 are both Al films 21 and 31, Ni plating films 22 and 32, and Pd plating films 23 and 33 in order from the one surface 41 side of the semiconductor element 40. The Au plating films 24 and 34 are laminated.

  On the other hand, as shown in FIG. 6, the first electrode 20 and the second electrode 30 of this embodiment are both Al films 21 and 31, Ni plating film 22 in order from the one surface 41 side of the semiconductor element 40. , 32 are laminated.

  In other words, in the present embodiment, the Pd plating films 23 and 33 and the Au plating films 24 and 34 in the first electrode 20 and the second electrode 30 of the first embodiment are omitted. Both the electrodes 20 and 30 of this embodiment use the same plating method as that of the first embodiment, and the first electrode 20 and the second electrode 30 are only subjected to Ni plating. It is formed.

  Specifically, the semiconductor device S6 of this embodiment is manufactured as follows. First, the Al films 21 and 31 are formed on the one surface 41 of the semiconductor element 40 by vapor deposition or the like. Then, Ni plating films 22 and 32 are formed on the Al films 21 and 31. Thereby, the semiconductor element 40 having both the electrodes 20 and 30 of the present embodiment is completed.

  Next, similarly to the above, mounting of the semiconductor element 40 on the substrate 10, soldering of the terminal 50, and wire bonding are sequentially performed. Thereby, the semiconductor device S6 of this embodiment is completed.

  As described above, the second electrode 30 of the present embodiment is configured such that the surface to which the wire 60 is bonded is constituted by the Ni plating film 32. According to this, since the surface of the second electrode 30 and the wire 60 are Ni and Al, the compatibility of bonding is good, and the bonding performance of wire bonding is ensured.

  Further, since the surface of the second electrode 30 is a Ni plating film 32 and the conventional Au plating film 34 does not exist thereon, Sn in the solder 80 adhering to the surface of the second electrode 30 is Ni. Even if it produces | generates and Sn-Ni alloy reacts, generation | occurrence | production of the above-mentioned Kirkendall void can be prevented. Therefore, according to this embodiment, peeling of the wire 60 due to heating can be prevented as much as possible.

(Seventh embodiment)
The seventh embodiment of the present invention is obtained by partially modifying the film configuration of the first electrode 20 for soldering in the sixth embodiment in which the surface of the second electrode 30 is a Ni plating film. Accordingly, the semiconductor device S7 according to the present embodiment will be described with reference to FIG. 7, focusing on differences from the sixth embodiment.

  In the sixth embodiment, the first electrode 20 is formed by laminating the Al film 21 and the Ni plating film 22 in order from the one surface 41 side of the semiconductor element 40. On the other hand, as shown in FIG. 7, the first electrode 20 of this embodiment is formed by laminating an Al film 21, a Ni plating film 22, and an Au plating film 24 in order from the one surface 41 side of the semiconductor element 40. It is supposed to be.

  That is, in the present embodiment, the first electrode 20 of the sixth embodiment has a film configuration in which an Au plating film 24 is further provided on the Ni plating film 22. In the sixth embodiment, the electrodes 20 and 30 of the present embodiment are selectively plated such that the first electrode 20 is subjected to Ni / Au plating while the second electrode 30 is subjected to Ni plating. It is formed by doing.

  Specifically, the semiconductor device S7 of this embodiment is manufactured as follows. First, Al films 21 and 31 are formed on one surface 41 of the semiconductor element 40 by vapor deposition or the like, and subsequently, Ni plating films 22 and 32 are formed on the Al films 21 and 31.

  Then, an Au plating film 24 is formed on the Ni plating film 22 in the first electrode 20 in a state where the Ni plating film 32 in the second electrode 30 is masked. Thereby, the semiconductor element 40 having both the electrodes 20 and 30 of the present embodiment is completed.

  Next, the mask on the Ni plating film 32 in the second electrode 30 is removed, and the semiconductor element 40 is mounted on the substrate 10, the terminal 50 is soldered, and wire bonding is sequentially performed as described above. Thereby, the semiconductor device S7 of this embodiment is completed.

  As described above, the second electrode 30 of the present embodiment is also configured such that the surface to which the wire 60 is bonded is constituted by the Ni plating film 32. Accordingly, as in the sixth embodiment, the bondability of wire bonding is ensured.

  Also in this embodiment, the surface of the second electrode 30 is a Ni plating film 32 as in the sixth embodiment, but even if Sn—Ni alloy is generated on the surface of the second electrode 30, Generation of the above-mentioned Kirkendall void can be prevented. Therefore, according to this embodiment, peeling of the wire 60 due to heating can be prevented as much as possible.

(Eighth embodiment)
The eighth embodiment of the present invention is obtained by partially modifying the film configuration of the first electrode 20 for soldering in the sixth embodiment in which the surface of the second electrode 30 is a Ni plating film. Therefore, the semiconductor device S8 according to the present embodiment will be described with reference to FIG. 8 focusing on differences from the sixth embodiment.

  In the sixth embodiment, the first electrode 20 is formed by laminating the Al film 21 and the Ni plating film 22 in order from the one surface 41 side of the semiconductor element 40. On the other hand, as shown in FIG. 8, the first electrode 20 of this embodiment has an Al film 21, a Ni plating film 22, a Pd plating film 23, and an Au plating film in order from the one surface 41 side of the semiconductor element 40. 24 is laminated.

  That is, in this embodiment, the first electrode 20 of the sixth embodiment has a film configuration in which a Pd plating film 23 and an Au plating film 24 are sequentially stacked on the Ni plating film 22. Such electrodes 20 and 30 of this embodiment are selectively plated such that the first electrode 20 is subjected to Ni / Pd / Au plating and the second electrode 30 is subjected to Ni plating in the sixth embodiment. It is formed by doing.

  Specifically, the semiconductor device S8 of this embodiment is manufactured as follows. First, Al films 21 and 31 are formed on one surface 41 of the semiconductor element 40 by vapor deposition or the like, and subsequently, Ni plating films 22 and 32 are formed on the Al films 21 and 31.

  Then, with the Ni plating film 32 in the second electrode 30 masked, a Pd plating film 23 and an Au plating film 24 are sequentially formed on the Ni plating film 22 in the first electrode 20. Thereby, the semiconductor element 40 having both the electrodes 20 and 30 of the present embodiment is completed.

  Next, the mask on the Ni plating film 32 in the second electrode 30 is removed, and the semiconductor element 40 is mounted on the substrate 10, the terminal 50 is soldered, and wire bonding is sequentially performed as described above. Thereby, the semiconductor device S8 of this embodiment is completed.

  As described above, the second electrode 30 of the present embodiment is also configured such that the surface to which the wire 60 is bonded is constituted by the Ni plating film 32. Accordingly, as in the sixth embodiment, the bondability of wire bonding is ensured.

  Also in this embodiment, the surface of the second electrode 30 is a Ni plating film 32 as in the sixth embodiment, but even if Sn—Ni alloy is generated on the surface of the second electrode 30, Generation of the above-mentioned Kirkendall void can be prevented. Therefore, according to this embodiment, peeling of the wire 60 due to heating can be prevented as much as possible.

(Other embodiments)
In each of the embodiments described above, the substrate 10 is used for supporting the semiconductor element 40 and for electrical connection. However, for example, if the semiconductor element 40 is stably supported by some method and the semiconductor element 40 can be electrically exchanged with the outside, the above-described substrate 10 may be omitted. .

  In the above embodiment, the power element is used as the semiconductor element 40. However, the first electrode 20 to which the terminal 50 is soldered and the second electrode 30 to which the Al wire 60 is wire-bonded are arranged on the same surface 41. If it has, the semiconductor element 40 is not limited to a power element.

  In addition to the Al films 21 and 31, the metallized film of the first electrode 20 in each of the embodiments and the metallized film of the second electrode 30 in the first, second, and sixth to eighth embodiments, A Cu film or the like may be used. The first electrode 20 and the second electrode 30 may be made of different materials for the metallized film.

  Furthermore, in each said embodiment, the 1st electrode 20 should just be the thing in which the terminal 50 can be solder-joined with the solder 80 containing Sn, and various structures suitably other than the structure shown to each said embodiment. Can be adopted.

  Of course, a single semiconductor device may include a plurality of semiconductor elements 40. Further, in one semiconductor element 40, it is needless to say that a plurality of first electrodes 20 for soldering and second electrodes 30 for wire bonding may be provided.

  Further, the present invention is not limited to the above-described embodiment, and can be appropriately changed within the scope described in the claims. The above embodiments are not irrelevant to each other, and can be combined as appropriate unless the combination is clearly impossible, and the above embodiments are not limited to the illustrated examples. Absent. In each of the above-described embodiments, it is needless to say that elements constituting the embodiment are not necessarily essential unless explicitly stated as essential and clearly considered essential in principle. Yes. Further, in each of the above embodiments, when numerical values such as the number, numerical value, quantity, range, etc. of the constituent elements of the embodiment are mentioned, it is clearly limited to a specific number when clearly indicated as essential and in principle. The number is not limited to the specific number except for the case. Further, in each of the above embodiments, when referring to the shape, positional relationship, etc. of the component, etc., the shape, unless otherwise specified and in principle limited to a specific shape, positional relationship, etc. It is not limited to the positional relationship or the like.

DESCRIPTION OF SYMBOLS 10 Substrate 20 1st electrode 30 2nd electrode 31 Al film of 2nd electrode 32 Ni plating film of 2nd electrode 33 Pd plating film of 2nd electrode 34 Au plating film of 2nd electrode 40 Semiconductor element 50 Terminal 60 Wire 80 Solder

Claims (6)

A semiconductor element (40) having a first electrode (20) for soldering and a second electrode (30) for wire bonding on one surface (41);
A terminal (50) joined to the first electrode via a solder (80) containing tin;
A wire (60) made of aluminum joined to the second electrode by wire bonding;
With
The second electrode has a Ni / Pd layer in which a surface to which the wire is bonded is formed by sequentially laminating a Ni plating film (32), a Pd plating film (33), and an Au plating film (34) from the semiconductor element side. / A semiconductor device characterized by being constituted by Au plating.   The second electrode has an Al film (31) or a Cu film as a metallized film bonded in direct contact with the semiconductor portion of the semiconductor element, and the Ni / Pd / Au is formed on the surface of the metallized film. The semiconductor device according to claim 1, wherein the semiconductor device is plated. A semiconductor element (40) having a first electrode (20) for soldering and a second electrode (30) for wire bonding on one surface (41);
A terminal (50) joined to the first electrode via a solder (80) containing tin;
A wire (60) made of aluminum joined to the second electrode by wire bonding;
With
The second electrode is made of an Al film (31) not containing Ni, and the surface to which the wire is bonded is a surface made of Al without being plated. Semiconductor device. A semiconductor element (40) having a first electrode (20) for soldering and a second electrode (30) for wire bonding on one surface (41);
A terminal (50) joined to the first electrode via a solder (80) containing tin;
A wire (60) made of aluminum joined to the second electrode by wire bonding;
With
The semiconductor device according to claim 2, wherein the second electrode has a surface on which the wire is bonded formed of a Ni plating film (32).   The second electrode has an Al film (31) or a Cu film as a metallized film bonded in direct contact with the semiconductor portion of the semiconductor element, and the Ni plating film is provided on the surface of the metallized film. The semiconductor device according to claim 4, wherein the semiconductor device is formed.   The semiconductor according to claim 1, wherein the first electrode is a source electrode of the semiconductor element, and the second electrode is a gate electrode of the semiconductor element. apparatus.

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