JP2019106480A - Metal member and semiconductor element using metal member, resin-metal composite, semiconductor device, different kind metal composite, and manufacturing method for metal member - Google Patents

Abstract

To realize a corrosion resistant metal member, and a semiconductor element, a semiconductor device, a resin-metal composite and different kind metal composite using the metal member, and a manufacturing method for the metal member.SOLUTION: Provided is a metal member in which at least a portion of one face 10a of a metal material 10 that is a main constituent element is a corrosion suppressive part 11 that is a region covered by a laminar metal thin-film 14 consisting of an oxide layer 141 composed mainly of an oxide of the metal material 10 and a non-oxide layer 142 composed mainly of the metal material or its nitride that are alternately laminated. A metal member having corrosion resistance thereby results, and a semiconductor element, etc., having corrosion resistance is obtained by using this. A manufacturing method for this metal member includes the steps of: fusing a portion of the metal material 10 by laser irradiation and evaporating it to form a plurality of roughened parts 12 having irregular shapes; and redepositing the evaporated portion of metal material 10 to the roughened parts 12 and the periphery thereof and solidifying the same to form a metal thin-film 14.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a metal member on the surface of which a roughened portion having a concavo-convex shape of nanometer order or micrometer order is formed, a semiconductor element using the metal member, a resin metal composite, a semiconductor device, and a dissimilar metal composite And a method of manufacturing the metal member.

  Conventionally, in order to provide the metal member with functions such as corrosion resistance, wear resistance and adhesion with other members, the surface of the metal member is formed by CVD (abbreviation of Chemical Vapor Deposition), vapor deposition, coating or the like on the surface of the metal member. Methods for forming functional thin films are known.

  However, this type of technique additionally requires a functional thin film material in addition to the metal member, and in the case of partially forming a functional thin film, a separate mask is also required, which complicates the process. Therefore, the metal member in which the functional thin film is formed by such a method, the composite using the metal member, and the like become expensive.

  Then, formation of the functional thin film by laser irradiation is proposed as a method which does not require the material and mask of a functional thin film separately. Specifically, laser irradiation is performed on a member provided with a metal member or a metal thin film such as plating to evaporate the metal material of the portion irradiated with the laser and reattach the evaporated metal material to the surface of the metal member. Solidify to form a functional thin film. Therefore, it is not necessary to separately prepare a material for the functional thin film and a mask, and a metal member having the functional thin film can be formed at a lower cost than conventional.

  As a thing provided with the metal member which has a functional thin film formed by such laser irradiation, the semiconductor device of patent document 1 is mentioned, for example. The semiconductor device described in Patent Document 1 includes a metal lead frame, an IC chip mounted on an island that is a part of the lead frame, and a mold resin that covers these. This lead frame corresponds to a metal member having a functional thin film, and is formed of an oxide or the like of a material constituting the metal member by laser irradiation, and the functional thin film having a concavo-convex microstructure has a mold of its surface It is formed in the part used as an interface with resin. As a result, the lead frame is formed on the surface with a shape that causes an anchor effect by the mold resin entering, and adhesion with the mold resin, that is, adhesion with other members is improved.

Patent No. 5983700

  However, since the functional thin film by the laser irradiation has a concavo-convex fine structure, it improves adhesion with other members but has a structure with insufficient wear resistance and corrosion resistance. Specifically, the convex portion of the functional thin film is a shape that is easily broken or scraped and hard to obtain wear resistance. Moreover, this convex part may become a cause of surface contamination of the said metallic member, when a part of the functional thin film scraped off to the other site | part of the metallic member in which the said functional thin film was formed adheres again. On the other hand, when the functional thin film is formed of a metal oxide, although the corrosion resistance of the metal member is improved, the concave portion of the functional thin film has a possibility of becoming a starting point of corrosion because the film thickness is thin.

  In addition, the metal member in which the functional thin film was formed is not restricted to said example, The resin metal joined body which joined the said metal member and the resin member, the dissimilar metal joining which joined the said metal member and the other metal member It can be applied to the body etc. Even in such a case, the same problem as described above is concerned.

  The present invention has been made in view of the above points, and provides a metal member having wear resistance and corrosion resistance, a semiconductor element using the metal member, a resin-metal composite, a semiconductor device, and a dissimilar metal composite. And it aims at providing a manufacturing method of the metal member concerned.

  In order to achieve the above object, the metal member according to claim 1 is a metal member comprising a metal material (10) having one surface (10a), and on one surface, on the nanometer order or micrometer order And a plurality of roughened portions (12) each having the concavo-convex shape are formed, the rough portion being a region surrounding the roughened portion in one surface when viewed from the normal direction to the one surface. And the surface (12a, 13a) of the roughening portion is covered with a metal thin film (14) comprising an oxide or nitride of the metal material, and the metal thin film is made of a metal material A layered film is provided including an oxide layer (141) mainly composed of an oxide and a non-oxidized layer (142) mainly composed of a metal material or a nitride of a metal material.

  According to this, a metal member in which a roughened portion having a concavo-convex shape of nanometer order or micrometer order, a roughened adjacent portion adjacent thereto and a metal thin film covering these surfaces are formed on a metal material having one surface It becomes. The metal thin film is a layered film including an oxide layer containing an oxide of a metal material as a main component and a non-oxidation layer containing the metal material or a nitride of the metal material as a main component. It is a shape that is less likely to be scraped and that a partially thin recess is less likely to occur. Therefore, the metal member is provided with wear resistance and corrosion resistance in the region where the metal thin film is formed.

The method of manufacturing a metal member according to claim 11 is a method of manufacturing a metal member provided on a metal material (10) having one surface (10a), which is prepared by preparing a metal material and laser irradiation. When forming a plurality of roughened portions (12) having a concavo-convex shape of nanometer order or micrometer order on at least a part of one side to form a corrosion suppression portion (110), and when forming the roughened portion By solidifying part of the evaporated metal material on the surface of the roughened adjacent portion (13) and the roughened portion, which is a region surrounding the roughened portion on one side, as viewed from the normal direction to one side, A layered metal thin film (14) comprising an oxide layer (141) mainly composed of an oxide of a metal material and a non-oxide layer (142) mainly composed of a metal material or a nitride of a metal material while covering Form And, equipped with a. Then, in forming by laser irradiation roughened portion performs N _2, Ar, at least one of CO ₂ under low oxygen atmosphere mainly.

Thereby, it is possible to manufacture a metal member in which a metal thin film which is a functional thin film is formed on one surface by laser irradiation, without using an additional material other than the metal material constituting the metal member. In addition, by performing laser irradiation in a low oxygen atmosphere containing at least one of N ₂ , Ar, and CO ₂ as a main component, an oxide layer containing an oxide of the metal material as a main component, and a metal material or metal. A metal thin film formed of a non-oxidized layer mainly composed of a nitride of a material is formed. Therefore, it becomes a layered metal thin film in which an oxide layer and a non-oxide layer are alternately laminated, and a metal member having abrasion resistance and corrosion resistance can be manufactured.

  In addition, the code | symbol in the parenthesis of each said means shows an example of the correspondence with the specific means as described in embodiment mentioned later.

1 is a cross-sectional view showing a semiconductor device of a first embodiment. It is the plane schematic diagram which looked at the semiconductor device of 1st Embodiment from the other surface side of an island part. It is a top view of the corrosion control part formed in one side of a metallic member. It is an expanded sectional view between IV-IV shown with the dashed-dotted line in FIG. It is an expanded sectional view of the area | region shown by the broken line in FIG. It is a figure which shows the formation process of a corrosion suppression part. It is a figure which shows the result of having observed the cross section of the metal thin film in a corrosion suppression part. It is a figure which shows the result of having mapped the nitrogen in the area | region shown with the dashed-dotted line in FIG. 7A. It is a figure which shows the result of having performed the mapping of the oxygen in the area | region shown with the dashed-dotted line in FIG. 7A. It is a perspective view which shows the semiconductor element of 2nd Embodiment. FIG. 9 is an enlarged cross-sectional view taken along the dotted line VII-VII in FIG. 8; It is a perspective view which shows the semiconductor element of 3rd Embodiment. FIG. 10 is an enlarged sectional view taken along the line XX in FIG. 9 as indicated by an alternate long and short dash line. It is a perspective view showing the metallic member of a 4th embodiment, and (a) is a perspective view, and (b) is an expanded sectional view when the metallic member is cut along the extension direction of the metallic member. is there. It is a figure which shows the heterometallic complex of other embodiment, Comprising: (a) is a perspective view, (b) is an expanded sectional view between XIIB-XIIB shown to (a).

  Hereinafter, an embodiment of the present invention will be described based on the drawings. In the following embodiments, parts that are the same as or equivalent to each other will be described with the same reference numerals.

First Embodiment
The semiconductor device of the first embodiment will be described with reference to FIGS. 1 to 7. The semiconductor device of the present embodiment is mounted, for example, on a vehicle such as a car and is applied as a device for driving various devices for the vehicle.

  In FIG. 2, in order to make the arrangement of the mold resin adjacent parts 211 and 223 described later intelligible, the boundary between the mold resin adjacent parts 211 and 223 and the other parts is shown by a broken line for convenience and can be seen in plan view. The IC chip 30 and the wiring member 40 which are eliminated are omitted. In FIG. 4, in order to make the configuration easy to understand, the boundary between the roughening portion 12 and the roughening adjacent portion 13 described later is indicated by a broken line for convenience.

  As shown in FIG. 1, the semiconductor device of this embodiment is made of a metal member 1 and includes a lead frame 20 having an island portion 21 and a lead portion 22, an IC chip 30, a wiring member 40, and a part of them. And a mold resin 50 covering the above.

In the semiconductor device of this embodiment, for example, a metal member 1 having corrosion resistance to a corrosive environment such as sulfuric acid or nitric acid caused by SO _x or NO _x is adopted as the lead frame 20. The semiconductor device of this embodiment has an arbitrary configuration except for the point of including such a metal member 1. Therefore, in the present embodiment, the metal member 1 and the lead frame 20 using the same will be mainly described, and the other components will be briefly described.

  The metal member 1 is mainly composed of the metal material 10 having the one surface 10a as shown in FIG. 3 or FIG. 5, and at least a part of the one surface 10a, that is, a corrosion suppression in which a portion to suppress corrosion is covered with the metal thin film 14 It is considered as part 11.

  In the present embodiment, a part of the surface 10a of the metal member 1 is the corrosion suppressing portion 11, but the entire surface of the surface 10a may be the corrosion suppressing portion 11, or the surface other than the surface 10a One part or all part may be made into the corrosion control part 11.

  The metal material 10 is made of, for example, a pure metal made of Cu, Fe or Al, or an alloy containing at least one of Cu, Fe, Al, Ni, Au, Pd, Ag and Sn as a main component. It is considered to be an alloy containing Ni as a main component.

  In addition, the "main component" here means the component in which the volume ratio in the whole of the metal material 10 occupies 50 vol% or more.

  The corrosion suppression part 11 is an area | region covered with the metal thin film 14 among the one surfaces 10a of the metal material 10, as shown in FIG. 3 or FIG. The corrosion suppression part 11 is comprised by the roughening adjacent part 13 which is an area | region which surrounds several roughening parts 12 and several roughening parts 12, as shown in FIG.

  The roughened portion 12 is a region having a concavo-convex shape of nanometer order or micrometer order, and is formed by laser irradiation. As shown in FIG. 3, the roughening portions 12 are separated from each other by a predetermined distance, for example, as viewed in the normal direction (hereinafter referred to as "one-plane normal direction") with respect to the surface 10a on which the roughening portion 12 is formed It is arranged.

  As shown in FIG. 4, the roughening portion 12 has a recess 121 which is a portion recessed to the metal member 1 side from the one surface 10 a and a protrusion 122 which is a portion protruding from the one surface 10 a to the opposite side of the recess 121. It consists of The recess 121 has a depth in the range of 0.1 to 50 μm in the direction normal to one surface between the flat surface of the surface 10 a and the bottom 121 a of the recess 121. The height of the convex portion 122, that is, the distance in the one surface normal direction between the plane formed by the one surface 10a and the most projecting portion of the convex portion 122 is arbitrary. In addition, the "bottom part 121a" here means the site | part recessed among the recessed parts 121 at the metal member 1 side.

  As shown in FIG. 3, the roughened adjacent portion 13 is a region different from the roughened portion 12 in the corrosion suppression portion 11, that is, a region surrounding the periphery of the plurality of roughened portions 12 as viewed in the normal direction of one surface. It is.

  The metal thin film 14 is a layered film including an oxide layer 141 mainly composed of an oxide of the metal material 10 and a non-oxide layer 142 as shown in FIG. 5, and the oxide layer 141 improves the corrosion resistance. Play a role.

  Note that the non-oxidized layer 142 may be configured to have other than the oxide of the metal material 10 as a main component, for example, to have the metal material 10 or a nitride thereof as a main component, It is also good.

  As shown in FIG. 5, the metal thin film 14 has a structure in which the oxide layer 141 and the non-oxide layer 142 are alternately and repeatedly laminated, and in the present embodiment, two oxide layers 141 and two non-oxide layers 142 are formed. Prepare. The outermost surface of the metal thin film 14 is an oxide layer 141. The film thickness of the metal thin film 14 in the direction normal to the surface of the roughened portion 12 or the roughened adjacent portion 13 on which the metal thin film 14 is formed is, for example, in the range of 5 nm to 5 μm.

  Note that the term "main component" as used herein refers to a component in which the volume ratio of the whole of the oxide layer 141 or the non-oxide layer 142 accounts for 50 vol% or more. Further, the steps of forming the roughening portion 12 and the metal thin film 14, the arrangement of the roughening portion 12 and the roughening adjacent portion 13, and the like will be described in detail later.

  The lead frame 20 described below is configured by the metal member 1 having such a structure.

  The lead frame 20 is provided with an island portion 21 and a lead portion 22 as shown in FIG. The lead frame 20 is configured to include an island portion 21 and a lead portion 22 by, for example, pressing the metal member 1 formed into a plate-like metal plate.

  As shown in FIG. 1, the island portion 21 has one surface 21 a and the other surface 21 b in a relationship of front and back. An IC chip 30 is mounted on the one surface 21 a via a bonding material such as solder (not shown). One surface 21 a of the island portion 21 is covered with a mold resin 50. In the present embodiment, the other surface 21 b of the island portion 21 is exposed from the mold resin 50 as shown in FIG. 1 or 2.

  As shown in FIG. 1, the lead portion 22 is electrically connected to the IC chip 30 mounted on the island portion 21 via the wiring member 40. As shown in FIG. 1, the lead portion 22 is configured by an inner lead 221 which is a portion covered by the mold resin 50 and an outer lead 222 which is a portion exposed from the mold resin 50.

  The above-described corrosion suppressing portion 11 is formed on the other surface 21 b of the island portion 21 and a part of the lead portion 22. Specifically, as shown in FIG. 2, the corrosion suppressing portion 11 is a mold resin adjacent portion 211 or 223 which is a predetermined region adjacent to the boundary portion with the mold resin 50 among at least the other surface 21 b and the outer lead 222. It is formed in the whole area of

  From the viewpoint of further improving the corrosion resistance, the corrosion suppressing portion 11 may be formed on part or all of the surface of the island portion 21 other than the other surface 21 b and the surface of the inner lead 221. More preferably, it is formed on at least a part of the interface with This is because, even if corrosion occurs at the boundary between the mold resin 50 and the other surface 21 b of the island portion 21 or the outer lead 222, the corrosion suppression portion 11 is formed at the interface with the mold resin 50. This is also because the progress of corrosion and the exfoliation due to this are suppressed. Further, the area of the mold resin adjacent portions 211 and 223 is arbitrary. Furthermore, although the semiconductor device of this embodiment is shown about the example made into SOP (abbreviation for Small Outline Package) in FIG. 2, it is not restricted to this, Other packages, such as QFP (abbreviation for Quad Flat Package) It may be structured.

  By forming the corrosion suppressing portion 11 in the entire region of the mold resin adjacent portions 211 and 223, the occurrence of corrosion at the relevant portion is suppressed. As a result, corrosion occurs in a portion of the lead frame 20 covered by the mold resin 50, particularly at the boundary with the mold resin 50, and this corrosion is prevented from proceeding to the inside of the mold resin 50. Further, peeling of the mold resin 50 from the lead frame 20 is also suppressed with the corrosion of the metal material 10 constituting the metal member 1 as a starting point.

  The IC chip 30 is, for example, a semiconductor element such as a MOS transistor or an IGBT (insulated gate bipolar transistor), and the like, and is manufactured by a normal semiconductor process or the like. The IC chip 30 has, for example, a rectangular plate shape, and an electrode pad (not shown) is formed on the surface on the opposite side of the island portion 21. As shown in FIG. It is connected to the.

  In the present embodiment, the wiring member 40 is a wire made of a conductive material such as Au or Al, for example, and is electrically connected to the IC chip 30 and the lead portion 22 by wire bonding.

  The mold resin 50 is made of, for example, an epoxy resin, PPS (polyphenylene sulfide), PBT (polybutylene terephthalate), nylon, urethane, silicone, LCP (liquid crystal polymer) or the like, and is formed by transfer molding or the like. As shown in FIG. 1, the mold resin 50 covers the one surface 21 a side of the island portion 21, the IC chip 30, the wiring member 40, and a part of the lead portion 22.

  The above is the configuration of the semiconductor device of the present embodiment.

  Next, an example of a method of manufacturing the semiconductor device of the present embodiment will be described. However, in the semiconductor device of the present embodiment, an arbitrary method of manufacturing a semiconductor device is adopted except that the corrosion suppressing portion 11 is formed on the metal member 1, that is, the lead frame 20. Therefore, first, the entire process including the process of forming the corrosion suppression unit 11 will be briefly described, and then the process of forming the corrosion suppression unit 11 will be described in detail.

  First, for example, a metal plate made of a metal material 10 such as Cu is prepared, and the metal plate is formed into a shape of the lead frame 20 having the island portion 21 and the lead portion 22 by press processing or the like. Then, the corrosion suppressing portion 11 is formed by laser irradiation on a portion that will become a part of the other surface 21 b and the lead portion 22 later exposed from the mold resin 50 in the molded metal plate, that is, a portion to prevent corrosion. As a result, the lead frame 20 including the corrosion suppression unit 11 is formed.

  Next, the IC chip 30 is prepared, and the IC chip 30 is mounted on one surface 21 a of the island portion 21 using a bonding material such as solder. Then, the electrode pads and the like formed on the surface of the IC chip 30 on the opposite side to the island portion 21 and the lead portion 22 are connected to the IC chip 30 and the lead portion 22 through a wire such as Au by wire bonding. Connect electrically.

  Subsequently, for example, a mold consisting of an upper mold and a lower mold provided with a cavity is prepared, and the lead frame 20 on which the IC chip 30 is mounted and wire bonded is set in the mold. Thereafter, for example, an epoxy resin which is a material of the mold resin 50 is poured into the cavity of the mold, and is heated and cured to form the mold resin 50. Then, by releasing the work in the mold from the mold, the semiconductor device of this embodiment can be obtained.

  Next, the specific formation process of the corrosion suppression part 11 is demonstrated with reference to FIG. In addition, although the corrosion suppression part 11 is formed after shaping | molding the metal material 10 in the shape of the lead frame 20 in fact, in order to make a process intelligible, the corrosion suppression part 11 is made to the metal material 10 for convenience here. An example of formation will be described.

  The formation process of the corrosion suppression portion 11 mainly includes a formation step of the roughened portion 12 by laser irradiation and a formation step of the metal thin film 14 after the laser irradiation. Specifically, the step of forming the roughened portion 12 is performed by melting and evaporating a part of the metal material 10 by laser irradiation. The step of forming the metal thin film 14 is performed by causing the metal material 10 evaporated by the laser irradiation to partially adhere to the roughened portion 12 and the roughened adjacent portion 13 so as to be solidified.

  The process of melting and evaporation by laser irradiation and the process of redeposition and solidification of a part of the metal material 10 evaporated by laser irradiation are instantaneously and continuously performed in this order. However, here, in order to make the formation process of the corrosion suppression part 11 intelligible, it divides into above-mentioned two processes for convenience, and demonstrates.

  First, as shown in FIG. 6A, a metal material 10 having one surface 10a, for example, a metal plate made of Ni is prepared. Then, as a step of melting and evaporating a part of the metal material 10 by laser irradiation, as shown in FIG. 6A, the metal material 10 is irradiated with a pulsed laser beam at a predetermined position. Then, as shown in FIG. 6B, the portion of the laser irradiation region R irradiated with the laser beam is melted and a portion thereof is evaporated.

Specifically, when the metal member 1 is irradiated with a laser beam, a part thereof evaporates in the laser irradiation region R of the surface 10a, and the rest is melted. The pulsed laser beam is adjusted, for example, to have an energy density of 100 J / cm ² or less, a pulse width of 1 μsec or less, and a wavelength of 200 nm to 11 μm. For example, the energy density is 50 J / cm ² , the pulse width is 200 nanoseconds, the wavelength is 1064 nm, the laser irradiation area R is adjusted to a diameter of 100 μm, and the Ni is irradiated with the laser beam.

Here, the energy density of the pulsed laser beam is in the range of 0.5 J / cm ² or more and 100 J / cm ² or less when the pulse width is on the nanosecond order, though it depends on the pulse width, that is, the peak intensity. Is preferred. If the energy density of the pulsed laser beam is too low, for example, about 0.1 J / cm ² , the metal member 1 does not sufficiently melt and evaporate, so that the roughened portion 12 is difficult to form. On the other hand, although the roughened portion 12 and the metal thin film 14 can be formed even when the energy density of the pulsed laser beam is larger than 100 J / cm ² , if the metal member 1 is melted or evaporated too much and is scattered to another region , Because splashes can be a source of contamination.

The laser is not particularly limited, but for example, a YAG laser or a CO ₂ laser can be used.

The laser irradiation is performed in a low oxygen atmosphere containing at least one of N ₂ , Ar, He, and CO ₂ as a main component. According to the experimental results of the present inventors, it is preferable that the oxygen concentration at least under the low oxygen atmosphere be 1.0% or less. By performing laser irradiation in a low oxygen atmosphere having an oxygen concentration of at least 1.0% or less, the metal thin film 14 described later has a layered configuration in which the oxide layers 141 and the non-oxide layers 142 are alternately stacked. It is because it becomes a film having corrosion resistance. Although the influence of the oxygen concentration on the shape of the metal thin film 14 is unknown at present, it is considered that the metal thin film 14 can be formed into a layer by making the energy of some evaporated metal materials 10 less likely to be lost by oxidation. .

  In addition, it is sufficient that a narrow space including a region where at least laser irradiation is performed and a part of the evaporated metal material 10 scatters and reattaches is set to a low oxygen atmosphere. Therefore, the low oxygen atmosphere may be created by filling the entire space including the narrow space, for example, the entire space in the laser irradiation apparatus with the above gas, or blowing the above gas into the narrow space. May be produced by

  Next, as a process of redeposition and solidification of a part of the metal material 10 evaporated by the laser irradiation, as shown in FIG. 6C, the rough part of the evaporated metal material 10 is formed by the laser irradiation. It is made to adhere again to the surface of the plating portion 12 and its surrounding, and this is solidified (solidified). Thereby, as shown in FIG. 6C, a part 15 of the metal thin film 14 is formed.

  At this time, the metal material 10 has a temperature (° C.) lower than the melting point (° C.) of the metal material 10 constituting the metal material 10 and higher than room temperature, for example, 1/3 to 2 / to the melting point (° C.) It is preferable to be in a state of being heated to a temperature (° C.) of 3. Specifically, in the case where Ni is a main component, the metal material 10 is in the range of 485 to 970 ° C., which is a temperature of 1/3 to 2/3 of the melting point 1455 ° C., and in the case where Al is a main component. It is preferable to heat in the range of 220-440 degreeC which is the temperature of 1/3-2/3 of melting | fusing point 660 degreeC. As a result, the metal thin film 14 has a layer-like dense structure, is easy to obtain a uniform or nearly uniform film thickness, and becomes a film having corrosion resistance and wear resistance.

  In the process of reattachment and solidification of the metal material 10, the metal thin film 14 can be obtained without heating the metal material 10, but it is more densely structured in a more layered structure by heating the metal material 10 as described above. 14 is preferable because it is easy to obtain. Although the reason why the layered metal thin film 14 is formed is unclear at present, from the experimental results of the present inventors, a sudden energy loss between redeposition and solidification of some evaporated metal material 10 is It is presumed that suppression is a necessary condition for forming a layered dense film. It is considered that the reason why heating is preferable is that preheating of the metal material 10 reduces energy loss when some of the evaporated metal material 10 reattaches.

  Here, “layered” does not have a porous shape as in the functional thin film described in Patent Document 1, but has a shape in which an oxidized layer 141 and a non-oxidized layer 142 with few local irregularities are laminated. Means Further, "uniform or nearly uniform" as used herein means that there are few local irregularities and that there is almost no part where the metal thin film 14 is extremely thin.

  In addition, after the metal material 10 which has been evaporated is diffused in a low oxygen atmosphere, a part of the metal material 10 is oxidized and redeposited on the roughened portion 12 and the roughened adjacent portion 13 so that the oxidized layer 141 is solidified. Form The remaining unoxidized portion of the evaporated part of the metal material 10 adheres again to the roughened portion 12 and the roughened adjacent portion 13 to form a non-oxidized layer 142 by solidification. It is expected that a difference in energy occurs between the oxidized part and the non-oxidized part of the evaporated part of the metal material 10, causing a time difference until redeposition. Therefore, it is considered that the metal thin film 14 has a structure in which the oxide layer 141 and the non-oxide layer 142 are stacked.

  Next, as shown in FIG. 6 (d), in the same procedure as described in FIGS. 6 (a) and 6 (b), the laser is changed at a predetermined interval from the roughened portion 12 formed immediately before and the laser is The beam is irradiated to melt and evaporate a part of the metal material 10 of the previous and another parts.

  Subsequently, as shown in FIG. 6 (e), in the same procedure as described in FIG. 6 (c), a part of the evaporated metal material 10 is redeposited and solidified. Then, as shown in FIG. 6 (e), evaporation and reattachment and solidification occur by forming another roughened portion 12 on the portion 15 of the redeposited and solidified metal thin film 14. Thus, a portion 15 of the metal thin film 14 formed by the above process is stacked. Hereinafter, by changing the laser irradiation area, by repeating the procedure described in FIGS. 6 (d) and 6 (e), the portion of the one surface 10a of the metal material 10 where corrosion is to be suppressed is corroded with the metal thin film 14 formed. It becomes the suppression part 11.

  The metal member 1 provided with the corrosion suppression part 11 is obtained by the above process.

  According to the experimental results of the present inventors, a part of the metal material 10 evaporated when forming the roughened portion 12 does not adhere to the roughened portion 12 very much, and the roughened portion It reattaches to a part of the roughened adjacent part 13 surrounding the part 12 and the other roughened part 12 and solidifies. That is, by forming a plurality of roughening portions 12, the oxide layer 141 and the non-oxide layer 142 that constitute the metal thin film 14 are alternately and repeatedly laminated.

  Therefore, in the metal thin film 14, a plurality of corrosion-resistant oxide layers 141 are stacked via the non-oxide layer 142. Therefore, even if the metal thin film 14 progresses corrosion beyond what is disposed on the outermost layer among the oxide layers 141, another oxide layer 141 prevents the progress of the corrosion. Therefore, the metal thin film 14 is a film having high corrosion resistance as compared to a conventional porous film such as the functional thin film described in Patent Document 1.

  Next, the result of having confirmed the structure of the metal thin film 14 formed in the metal member 1 is demonstrated with reference to FIG. 7A-FIG. 7C. In FIG. 7A-FIG. 7C, it is a result of having observed by TEM-EELS which combined TEM (transmission electron microscope) and EELS (electron energy loss spectroscopy) about the cross section of the part in which the metal thin film 14 was formed among the metallic members 1. Is shown.

  As shown in FIG. 7A, the metal thin film 14 has a configuration in which a white layer and a black layer are alternately and repeatedly laminated on the underlying metal material 10. When the composition was confirmed by enlarging a part of the metal thin film 14, the metal thin film 14 is formed with a layer containing a large amount of nitrogen shown in white at the interface with the metal member 1, as shown in FIG. 7B. . Then, as shown in FIG. 7B, in the metal thin film 14, a white layer and a black layer containing less nitrogen are repeatedly laminated in this order from the metal material 10 side to the opposite side of the metal material 10, and the outermost surface is black. It is considered to be a layer. As shown in FIG. 7C, in the metal thin film 14, a white layer containing a large amount of oxygen is formed on the outermost surface, and a black layer containing a small amount of oxygen is formed thereunder, and these are alternately stacked. Combining these results, the metal thin film 14 is configured such that the non-oxidized layer 142 and the oxide layer 141 are repeatedly laminated in this order in order from the metal material 10 side, and the outermost surface is the oxide layer 141 That was confirmed.

  Next, the arrangement of the roughened portion 12 in the corrosion suppression portion 11, that is, the interval of laser irradiation will be described with reference to FIG.

  In this embodiment, the horizontal direction in FIG. 3 is taken as the X direction, and the direction orthogonal to the X direction is taken as the Y direction on the plane of the drawing sheet of FIG. The laser beam is sequentially irradiated to a part of the metal material 10 by moving the

  Specifically, the diameter of the laser irradiation region R, that is, the spot diameter is set to, for example, several tens of μm, and a plurality of points are provided such that the interval between the centers of adjacent spot diameters (hereinafter referred to as “laser irradiation interval”) becomes a predetermined range. Laser irradiation. The laser irradiation interval is preferably in the range of 0 to 20 times the spot diameter. This is because the metal thin film 14 continuously covers the adjacent roughened portions 12 without gaps. For example, when the spot diameter is φ60 μm, the laser irradiation interval is preferably in the range of 0 to 1200 μm. In other words, when viewed from the normal direction of one surface, in the roughened portion 12, the distance between the centers of the diameters of the roughened portion 12 and the adjacent roughened portion 12, ie, the distance between the spots It is preferable to be in the range of 0 to 20 times the diameter.

  In addition, since it is sufficient to move the metal material 10 relative to the laser light source for irradiating the laser beam when irradiating the laser beam, one of the laser light source or the metal material 10 is fixed and the other is moved. Good. In addition, the laser irradiation interval is adjusted by appropriately setting, for example, the operation speed of the laser light source, the moving speed of the stage on which the metal material 10 is mounted, the pulse repetition frequency, and the like. Furthermore, although the laser irradiation interval is illustrated in FIG. 3 as an example in which the X direction and the Y direction are the same, the present invention is not limited thereto, and the X direction and the Y direction may be different. May be That is, the roughening unit 12 is not limited to the arrangement example shown in FIG. 3, and the arrangement may be changed as appropriate.

  According to the present embodiment, since the metal member 1 in which the corrosion suppressing portion 11 is formed is adopted as the lead frame 20, corrosion resistance is imparted, and peeling of the mold resin 50 caused by corrosion and corrosion is suppressed. It becomes a semiconductor device. Further, in the semiconductor device of the present embodiment, when the corrosion suppressing portion 11 is formed at the interface with the mold resin 50 in the lead frame 20, the anchor effect by the roughened portion 12 having the concavo-convex shape makes the semiconductor device with the mold resin 50. Adhesiveness is secured. Furthermore, since the outermost surface of the region in which the corrosion suppression portion 11 is formed is covered with the layered metal thin film 14, it is hard to cause breakage or scraping, and wear resistance is secured.

  Further, since the corrosion suppression portion 11 is formed by irradiating the metal material 10 with a laser, a metal including the corrosion suppression portion 11 which performs a function such as corrosion resistance without separately using a material other than the metal material 10 or a mask. The member 1 can be formed. And a semiconductor device with corrosion resistance can be manufactured by using metal member 1 provided with corrosion control part 11 formed by such a method.

Second Embodiment
The semiconductor device of the second embodiment will be described with reference to FIG. 8 and FIG. Although the cross section is not shown in FIG. 8, the corrosion suppressing portion 11 is hatched to make it easy to understand the arrangement of the corrosion suppressing portion 11 described later. Although in FIG. 9 the corrosion suppressing portion 11 is simplified and its thickness is exaggerated for simplicity of the configuration, the structure of the corrosion suppressing portion 11 is the same as that of the first embodiment.

  The semiconductor device of the present embodiment includes an IC chip 30 and an electrode pad 31 formed on one surface 30 a of the IC chip 30. The semiconductor device of this embodiment is an example in which the metal member 1 of the first embodiment is applied as the electrode pad 31. The semiconductor device of the present embodiment is the same as an IC chip formed by a normal semiconductor process except that the semiconductor device of the present embodiment is provided with the electrode pad 31 formed of the metal member 1. The pad 31 will be mainly described.

  The electrode pad 31 is mainly made of the metal material 10, and in the present embodiment, it is a metal having one of Ni, Al, Cu, etc. as a main component or an alloy thereof. The electrode pad 31 is formed on one surface 30 a of the IC chip 30 by electrolytic plating or the like, and as shown in FIG. 8, the wiring member 40 is connected to the surface 31 a which is the opposite surface of the IC chip 30. In the electrode pad 31, the corrosion suppressing portion 11 is formed in a portion of the surface 31 a to which the wiring member 40 is not connected. Therefore, from the viewpoint of bonding property and formation of the corrosion suppressing portion 11, the electrode pad 31 has good bonding property with the wiring member 40 made of, for example, Cu, Al or an alloy thereof, and is made of a metal that oxidizes or nitrides. Is preferred.

  The wiring member 40 is, for example, a wire made of Au or the like, a connector, or a conductive adhesive made of solder, Ag paste or the like, but in the present embodiment, it is a wire as shown in FIG.

  The corrosion suppression part 11 is formed by laser irradiation, for example, after the wiring member 40 is connected. The conditions and the like of the laser irradiation are the same as those of the above-described first embodiment, and thus the description thereof will be omitted in this embodiment.

  In the present embodiment, as shown in FIG. 8, the corrosion suppressing portion 11 is formed in part of a portion (hereinafter referred to as “non-connecting region”) of the surface 31 a of the electrode pad 31 to which the wiring member 40 is not connected. However, the corrosion suppression portion 11 may be formed in the entire non-connection area. In other words, the corrosion suppressing portion 11 is formed so as to partially or entirely surround the wiring member 40 when viewed in the normal direction to the surface 10 a of the metal material 10.

  Even if there is a region (hereinafter referred to as a “non-laser region”) where the laser irradiation can not be performed because the wiring member 40 itself becomes an obstacle in the non-connection region of the surface 31a, the non-laser region It is also possible to form a metal thin film 14 on the Specifically, as described in the description of the step of forming the corrosion suppressing portion 11 in the first embodiment, the metal thin film 14 is a roughened adjacent portion 13 around the roughened portion 12 formed by laser irradiation. That is, it is also formed in the area where the laser irradiation is not performed. Therefore, even if the non-laser area exists, the metal thin film 14 is formed also in the non-laser area by performing laser irradiation on the surrounding area.

  According to the present embodiment, the wiring member 40 connected to the electrode pad 31 is a semiconductor element in which the peeling by the corrosion of the electrode pad 31 is suppressed.

Third Embodiment
The semiconductor device of the third embodiment will be described with reference to FIGS. 10 and 11. FIG. Although the cross section is not shown in FIG. 10, the corrosion suppressing portion 11 is hatched in order to make the arrangement of the corrosion suppressing portion 11 easy to understand. Although FIG. 11 illustrates the corrosion suppressing portion 11 in a simplified manner and exaggerates the thickness as in FIG. 9, the configuration is the same as that of the first embodiment.

  The semiconductor device of the present embodiment includes an IC chip 30 and an electrode pad 32 formed on one surface 30 a of the IC chip 30. The electrode pad 32 is composed of a first member 321 joined to the wiring member 40, and a second member 322 surrounding the first member 321 and having the corrosion suppressing portion 11 formed on one surface 322a thereof. The semiconductor device of the present embodiment is different from the second embodiment in that the metal member 1 is applied as the second member 322. In the present embodiment, this difference is mainly described.

  The first member 321 is connected to a wiring member 40 made of, for example, Cu, Al, Au or an alloy thereof as shown in FIG. The first member 321 is made of, for example, a metal material having a good bonding property with the wiring member 40 such as Cu, Al, Ni, Au or an alloy thereof, and is formed by an electrolytic plating method or the like.

  In the first member 321, as shown in FIG. 10 or FIG. 11, the metal thin film 14 is formed on a part of the surface 321a which is the opposite surface of the IC chip 30 to which the wiring member 40 is not connected. There is. In the portion of the metal thin film 14 covering the first member 321, when forming the corrosion suppressing portion 11 in the second member 322, part of the material of the second member 322 evaporated by laser irradiation is one surface 321a of the first member 321 It is formed by reattaching to and coagulating.

  The second member 322 is mainly made of the metal material 10, and in the present embodiment, is an alloy containing, for example, at least one of Cu, Fe, and Al as a main component, and is formed by an electrolytic plating method or the like. The second member 322 is a member not used for bonding with the wiring member 40, and has a frame shape surrounding the first member 321 when viewed from the normal direction to the one surface 30a of the IC chip 30. In the second member 322, as shown in FIG. 10 or FIG. 11, the corrosion suppression portion 11 is formed by laser irradiation on one surface 322a which is the opposite surface of the IC chip 30 as in the second embodiment. .

  In addition, although the corrosion suppression part 11 is formed in the whole surface of the one surface 322a of the 2nd member 322 in FIG. 10, it should just be formed in at least one part.

  According to this embodiment, the same effect as the semiconductor device of the second embodiment can be obtained. In addition, since the first member 321 which is a bonding member used for bonding with the wiring member 40 is not subjected to laser irradiation, a semiconductor provided with the electrode pad 32 with high corrosion resistance while suppressing damage to the bonding member by laser irradiation. It becomes an element.

Fourth Embodiment
The metal member of the fourth embodiment will be described with reference to FIG. Although the cross section is not shown in FIG. 12A, the corrosion suppressing portion 11 is hatched in order to make the arrangement of the corrosion suppressing portion 11 easy to understand. In FIG.12 (b), in order to make a structure intelligible, while simplifying the corrosion suppression part 11, the thing which exaggerated the thickness is shown.

  The metal member of this embodiment is an example applied to the metal parts of the injector nozzle used for a part of fuel injection valve in vehicles, such as a car, for example.

  As shown in FIG. 12A or 12 B, the metal member of the present embodiment is a cylindrical body 60 having a substantially cylindrical shape, and includes a through hole 61 and an injection port 62.

  The cylindrical body 60 is mainly made of the metal material 10, and in the present embodiment, it is an alloy containing, for example, at least one of Cu, Fe, and Al as a main component. Of the outer wall surface 60a of the cylindrical body 60, the tip surface 60b which is the surface on the side of the injection port 62, and the inner wall surface 60c of the through hole 61, a portion adjacent to the tip surface 60b is shown in FIG. The corrosion suppressing portion 11 is formed.

  12A, the corrosion suppressing portion 11 is formed on the entire surface of the outer wall surface 60a and the tip end surface 60b, but the corrosion suppressing portion 11 is formed only on a portion where corrosion is to be suppressed, that is, only a part. It may be

  Unlike the conventional injector nozzle in which a thin film having corrosion resistance is formed on the surface by the conventional method of forming a functional thin film, the metal member of this embodiment separately uses a thin film material other than the metal material 10, a mask, etc. Because it is not necessary, it can be manufactured inexpensively. Further, since the corrosion suppressing portion 11 is formed by laser irradiation, it can be formed on a part of the inner wall surface 60c which is difficult to form by the conventional film forming method, and a part having corrosion resistance also on the inner wall surface 60c It becomes an injector nozzle provided.

Fifth Embodiment
The heterometallic complex of the fifth embodiment will be described with reference to FIG. Although the cross section is not shown in FIG. 13A, the corrosion suppressing portion 11 is hatched in order to make the arrangement of the corrosion suppressing portion 11 easy to understand.

  In the dissimilar metal composite of the present embodiment, as shown in FIG. 13A, for example, a first metal member 70 mainly composed of Al and a second metal member 80 mainly composed of Fe are joined. Become.

  The first metal member 70 is mainly made of the metal material 10 and corresponds to the metal member 1 provided with the corrosion suppression portion 11. In the first metal member 70, the second metal adjacent portion 70c which is a region adjacent to the joint portion 70b joined to the second metal member 80 by welding or the like in the one surface 70a is used as the corrosion suppression portion 11.

  The dissimilar metal composite according to the present embodiment is, for example, after the first metal member 70 and the second metal member 80 are joined by welding, the corrosion suppression portion is formed on the first metal member 70 by laser irradiation as in the first embodiment. Manufactured by forming 11.

  In the dissimilar metal complex of the present embodiment, the progress of corrosion from the region of the first metal member 70 exposed from the second metal member 80 toward the bonding portion is suppressed. Further, in the dissimilar metal composite of the present embodiment, when the first metal member 70 and the second metal member 80 are joined by welding, a region in which the corrosion suppression portion 11 is formed in the welded portion produced by welding It is expected that the residual stress will be relaxed in This is because, when laser irradiation is performed on the alloy portion of the first metal member 70 and the second metal member 80 generated by welding in the second metal adjacent portion 70c, the alloy portion is melted again and solidified. And the residual stress is released.

(Other embodiments)
In addition, the metal member shown to each above-mentioned embodiment, the composite_body | complex using the said metal member, etc. show an example of this invention, and are not limited to said each embodiment, A claim is claimed. Appropriate changes can be made within the range described in the above.

  (1) For example, in the first embodiment, the semiconductor device is described as an example of the resin-metal composite in which the metal member 1 having the corrosion suppressing portion 11 and the mold resin 50 as the resin member are joined. It goes without saying that the present invention may be applied to resin-metal composites.

  (2) In the first embodiment, the example in which the semiconductor device has a so-called half mold type structure in which the other surface 21 b of the island portion 21 is exposed from the mold resin 50 has been described. However, a so-called full mold type structure in which the metal member 1 in which the corrosion suppression portion 11 is formed is a semiconductor device adopted as the lead frame 20 and all the island portions 21 are covered with the mold resin 50 It may be taken.

  (3) In the first embodiment, the example in which the metal member 1 mainly made of the metal material 10 is adopted as the lead frame 20 has been described. However, the lead frame 20 is not limited to such an example, and is mainly composed of dissimilar metal materials other than the metallic material 10, and a plated layer composed of the metallic material 10 is applied on the surface of the dissimilar metal material. May be

  In this case, the plating layer corresponds to the metal member 1, and after the dissimilar metal material is coated with the metal material 10 by electrolytic plating or the like, the corrosion suppression portion 11 is formed on the metal material 10 by laser irradiation. And a corrosion resistant lead frame 20 is obtained. Even if the lead frame 20 having such a configuration is employed, a semiconductor device having corrosion resistance can be obtained. In this case, the metal material 10 is, for example, an alloy containing one of Ni, Au, Pd, Ag, Sn, etc. as a main component.

  In each of the embodiments other than the first embodiment, a different metal material other than the metal material 10 is mainly used, and a plating layer composed of the metal material 10 is applied to the surface of the different metal material. can do.

  (4) In the fifth embodiment, although the example in which the corrosion suppression portion 11 is formed in the portion exposed from the second metal member 80 of the one surface 70a of the first metal member 70 has been described, the second metal of the one surface 70a It may be formed on at least a part of the interface with the member 80. In this case, in the dissimilar metal complex, after the corrosion suppressing portion 11 is formed in advance on the first metal member 70 by laser irradiation, a part of the corrosion suppressing portion 11 and the second metal member 80 form an interface. Manufactured by joining by caulking or the like.

DESCRIPTION OF SYMBOLS 1 metal member 10 metal material 11 corrosion suppression part 12 roughening part 13 roughening adjacent part 14 metal thin film 141 oxide layer 142 non-oxide layer

Claims (16)

A metal member comprising a metal material (10) having one surface (10a), comprising:
At least a part of the one surface is a corrosion suppressing portion (11) including a plurality of roughening portions (12) which are regions having a concavo-convex shape of nanometer order or micrometer order,
The roughened portion and the roughened adjacent portion (13), which is a region surrounding the roughened portion in the one surface, when viewed from the normal direction to the one surface, the surface is the oxide or nitride of the metal material Covered by a thin metal film (14) comprising
The metal thin film is a layered film comprising an oxide layer (141) mainly composed of an oxide of the metal material and a non-oxidized layer (142) mainly composed of the metal material or a nitride of the metal material It is a metal member.   The metal member according to claim 1, wherein the metal thin film has a structure in which the oxidized layer and the non-oxidized layer are alternately and repeatedly laminated.   The metal member according to claim 2, wherein a thickness of the metal thin film in a direction normal to the surface is in a range of 5 nm to 5 μm.   The depth of the roughening portion is defined by the distance in the normal line direction between the bottom portion (121a) when viewed from the normal line direction and the plane formed by the roughened portion. The metal member according to any one of claims 1 to 3, which is in the range of 0.1 μm to 50 μm.   The metal material is a pure metal composed of any of Cu, Fe and Al, or an alloy composed mainly of at least one of Cu, Fe, Al, Ni, Au, Pd, Ag and Sn. The metal member according to any one of Items 1 to 4. A metal member (1) according to any one of claims 1 to 5;
And an IC chip (30),
The metal member is a plating layer which functions as an electrode pad (31, 322) formed on the IC chip,
The semiconductor element by which the wiring member (40) is connected to the part different from the said corrosion suppression part among the said metal members.   The semiconductor element according to claim 6, wherein the corrosion suppression portion is formed to partially or entirely surround the wiring member when viewed in a normal direction to the one surface. A metal member (1) according to any one of claims 1 to 5;
And a resin member covering a part of the metal member,
The corrosion suppressing portion is a resin which is an area exposed from at least a part of an interface of the metal member with the resin member and at least a part of the metal member from the resin member and is adjacent to the resin member. Resin-metal complex formed in the adjacent part. A metal member (1) according to any one of claims 1 to 5;
IC chip (30),
A wiring member (40) electrically connecting a part of the metal member and the semiconductor element;
A mold resin (50) covering a part of the metal member, the semiconductor element, and the wire;
The metal member is a lead frame (20) having an island portion (21) on which the semiconductor element is mounted, and a lead portion (22) electrically connected to the semiconductor element through the wire.
The corrosion suppression portion is a region of at least a part of an interface of the island portion or the lead portion with the mold resin, and a region of the island portion or the lead portion exposed from the mold resin, The semiconductor device currently formed in the mold resin adjacent part (211, 223) which is an area | region adjacent to mold resin. A metal member (1) according to any one of claims 1 to 5;
And a second metal member (80) made of a metal material different from the first metal member as the first metal member (70).
The first metal member is joined to the second metal member,
The corrosion suppression portion is a region of at least a part of an interface of the first metal member with the second metal member and a region exposed from at least the second metal member of the first metal member. A dissimilar metal composite formed in a second metal adjacent portion (70c) which is a region adjacent to the second metal member. A method of manufacturing a metal member comprising a metal material (10) having one surface (10a), comprising:
Providing the metal material;
Forming a plurality of roughened portions (12) having a concavo-convex shape of nanometer order or micrometer order on at least a part of the one surface by laser irradiation to form a corrosion suppression portion (110);
A roughened adjacent portion (13), which is a region surrounding the roughened portion in the one surface, when a part of the metal material evaporated when forming the roughened portion is viewed from the normal direction to the one surface, and By solidifying the surface of the roughened portion, these are covered, and an oxide layer (141) mainly composed of the oxide of the metal material, and the metal material or a nitride of the metal material mainly Forming a layered metal thin film (14) comprising a non-oxidized layer (142);
Wherein in the roughened portion is formed by laser _irradiation, N 2, Ar, He, producing a metallic component carried out in a low oxygen atmosphere composed mainly of at least one of CO _2.   The metal member according to claim 11, wherein, in forming the metal thin film, the metal material is heated to a temperature (° C) higher than room temperature and lower than a melting point (° C) of the metal material. Production method.   In forming the metal thin film, the metal material is heated to a temperature (° C.) within a range of 1/3 to 2/3 of the melting point (° C.) of the metal material. The manufacturing method of the metal member as described in-.   The method for manufacturing a metal member according to any one of claims 11 to 13, wherein the oxygen concentration in the low oxygen atmosphere is 1.0% or less.   In forming the roughened portion by laser irradiation, the plurality of portions on the one surface are irradiated with the laser, and the diameter of the spot to be irradiated with the laser is X when viewed from the normal direction. The method for manufacturing a metal member according to any one of claims 11 to 14, wherein Y is in the range of 0 to 20 times X, where Y is a distance between the adjacent spots. In forming the roughened portion by laser irradiation, the pulse width of the laser is 1 μs or less, the energy density of the laser is 100 J / cm ² or less, and the wavelength of the laser is in the range of 200 nm to 11 μm. 15. A method of manufacturing a metal member according to any one of 15.