TW201831246A - Method for manufacturing wiring structure - Google Patents

Abstract

The present invention is directed to a method of manufacturing a wiring structure. It comprises a process of preparing a substrate (10) having a wiring layer (13) formed on the surface thereof with an insulating layer (11); a process of etching the back surface of the substrate to form a via hole (20), the via hole (20) along the thickness The direction penetrates the insulating layer (11) and has a bottom portion, and the wiring layer (13) is located below the bottom portion; a process of sequentially forming the first metal layer (15) and the second metal layer (16) on the bottom of the via hole and on the wiring layer; And a process of filling the Sn-based molten metal 17 into the via hole (20). The wiring layer is formed of Al, an Al alloy, or Cu; the first metal layer is formed of a material that forms an alloy with the Sn-based molten metal; and the second metal layer is formed of a material that prevents oxidation of the first metal layer.

Description

 Wiring structure manufacturing method  

The present invention relates to a method of manufacturing a wiring structure including a through electrode that penetrates a substrate in a thickness direction.

A wiring structure in which wiring layers formed on both surfaces of a substrate are electrically connected via a through electrode is known in the art. Here, the through electrode is formed by forming a via penetrating through the substrate in the thickness direction and filling a conductive material into the through hole.

A method of forming a wiring structure including a through electrode is, for example, a method called via last. In this method, after the integrated circuit is formed on the surface of the substrate, a through electrode that penetrates the substrate in the thickness direction is formed. In this case, before the through electrodes are formed, a wiring layer is formed on the surface of the substrate with an insulating film interposed therebetween. Further, the via hole is formed by etching from the back surface and penetrating through the insulating layer. At this time, the wiring layer is exposed at the bottom of the via hole, and the wiring layer and the through electrode can be electrically connected by filling the conductive material into the via hole.

For example, the technique of filling copper by electrolytic plating is one of techniques for filling a conductive material into a through hole. However, since the diameter of the through hole penetrating the substrate in the thickness direction is small and the aspect ratio is high, it is difficult to reliably fill the bottom of the through hole with copper, and if it is filled with copper by electrolytic plating, it is penetrated in the thickness direction. The through hole of the substrate takes a long time.

A technique of filling a molten metal into a through hole and then solidifying it (for example, refer to Patent Document 1) is one of other techniques well known in the art for filling a conductive material into a through hole. According to this technique, even a high aspect ratio through hole can easily fill the molten metal to the bottom of the through hole. Moreover, the time for filling the molten metal into the through hole can also be shortened.

[Previous Technical Literature]

[Patent Literature]

Patent Document 1: Japanese Laid-Open Patent Publication No. 2002-158191.

When a tin (Sn)-based molten metal is filled in a through hole to form a through electrode, when the wiring layer is formed of aluminum (Al), there is a problem in that contact failure occurs between the through electrode and the wiring layer. phenomenon. When the wiring layer is formed of copper (Cu), there is a problem that the wiring layer is poorly connected in the vicinity of the through electrode.

The present invention has been accomplished in view of the above problems. A main object of the invention is to provide a method for manufacturing a wiring structure in which a contact structure between a through electrode and a wiring layer is good in a wiring structure including a through electrode formed by filling a Sn-based molten metal into a via hole. The layer will not be poorly connected.

A manufacturing method of a wiring structure according to the present invention, comprising: a process (A) for preparing a substrate having a wiring layer formed on the first main surface with an insulating layer interposed therebetween; and a process (B) for selectively etching the substrate a through hole formed in the second main surface, the through hole penetrating the insulating layer in a thickness direction, and having a bottom portion, the wiring layer being located below the bottom portion; and a process (C) at the bottom portion corresponding to at least a bottom portion of the through hole A first metal layer and a second metal layer are sequentially formed on the wiring layer; and a process (D) is performed to fill the through-holes of the Sn-based molten metal. The wiring layer is formed of Al, an Al alloy or Cu; the first metal layer is formed of a material which forms an alloy with the Sn-based molten metal in the process (D); and the second metal layer prevents oxidation of the first metal layer The material is formed.

Another manufacturing method of the wiring structure of the present invention comprises: a process (A), preparing a substrate, and sequentially forming a second metal layer, a first metal layer and a wiring layer on the first main surface of the substrate with an insulating layer interposed therebetween; a process (B) of selectively etching a second main surface of the substrate to form a via hole penetrating the insulating layer and having a bottom portion, the wiring layer being located below the bottom portion; and a process (C) of class Sn The molten metal is filled into the aforementioned through holes. The wiring layer is formed of Al, an Al alloy, or Cu; the first metal layer is formed of a material that forms an alloy with the Sn-based molten metal in the process (C); and the second metal layer is formed by preventing the first metal layer The oxidized material is formed.

According to the present invention, it is possible to provide a method of manufacturing a wiring structure in which the contact between the through electrode and the wiring layer is good in a wiring structure including a through electrode formed by filling a Sn-based molten metal into a via hole. The layer will not be poorly connected.

10‧‧‧Substrate

10a‧‧‧ Surface of the substrate (first main surface)

10b‧‧‧Back side of the substrate (second main surface)

11‧‧‧Insulation

12‧‧‧ Tight adhesion layer

13‧‧‧Wiring layer

14‧‧‧Insulation film

15‧‧‧First metal layer

16‧‧‧Second metal layer

17‧‧‧Sn class molten metal (through electrode)

18‧‧‧First metal layer

19‧‧‧Second metal layer

20‧‧‧through hole

20a‧‧‧Bottom of the through hole

30‧‧‧Support

40‧‧‧resist pattern

50‧‧‧Support

51, 71‧‧‧ Drive Department

60‧‧‧Cylinder

70‧‧‧ Pressurization

80‧‧‧ container

81‧‧‧Pipe

82‧‧‧ molten metal

90, 91‧‧‧ Sealing parts

100‧‧‧Processing room

(a) to (c) of FIG. 1 are cross-sectional views, and schematically show a method of manufacturing the wiring structure according to the first embodiment of the present invention.

(a) to (d) of FIG. 2 are cross-sectional views, and schematically show a method of manufacturing the wiring structure according to the first embodiment of the present invention.

(a) to (c) of FIG. 3 are cross-sectional views, and schematically show a method of manufacturing the wiring structure according to the second embodiment of the present invention.

4(a) to 4(c) are cross-sectional views schematically showing a method of manufacturing the wiring structure according to the second embodiment of the present invention.

(a) of FIG. 5 and (b) of FIG. 5 are diagrams for explaining a method of filling a Sn-based molten metal into a through hole according to the present invention.

(a) of FIG. 6 and (b) of FIG. 6 are diagrams for explaining a method of filling a Sn-based molten metal into a via hole according to the present invention.

As the molten metal filled in the through hole, tin (Sn) having a lower melting point than aluminum (Al) or copper (Cu) which forms a wiring layer is used, and a through electrode is formed by Sn, and the inventors of the present application include the through The wiring structure of the electrode was studied and discussed, and the following problems were found.

That is, in the case where the wiring layer is formed of aluminum, a contact failure occurs between the wiring layer and the through electrode. In the case where the wiring layer is formed of copper, a phenomenon in which the wiring layer is poorly connected is generated in the vicinity of the through electrode.

The reasons for these problems are generally considered to be as follows. That is, when the through hole is formed by penetrating the substrate in the thickness direction, the wiring layer is exposed at the bottom of the through hole. However, since the process of filling the molten metal into the through hole is not performed by the process of forming the through hole through the substrate in the thickness direction (the process of exposing the wiring layer) is performed under vacuum, the filling of the molten metal is in the wiring layer. The surface is oxidized. Therefore, it is difficult to form a good contact between the wiring layer and the through electrode. In the case where a wiring layer is formed of aluminum, since aluminum is difficult to form an alloy with tin, the contact resistance between the wiring layer and the through electrode is increased. On the other hand, in the case where the wiring layer is formed of copper, the copper is likely to form an alloy with tin, but a part of the copper forming the wiring layer is diffused into the Sn of the through electrode. Therefore, a void is formed in the vicinity of the through electrode in the inside of the wiring layer. As a result, the conductivity of the wiring layer is lowered.

On the basis of the above knowledge, the inventors of the present application form a first metal layer which is alloyed with Sn on the surface of the through electrode which is in contact with the wiring layer exposed at the bottom of the through hole, and on the surface in contact with the through electrode, The second metal layer which prevents oxidation of the first metal layer is formed, and it has been found that the above problems can be solved by the above, and the present invention has been made.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that the present invention is not limited to the following embodiments. Appropriate changes can be made without departing from the scope of the invention.

(First embodiment)

(a) to (c) of FIG. 1 and (a) of FIG. 2 to (d) of FIG. 2 are cross-sectional views, and schematically show a method of manufacturing the wiring structure according to the first embodiment of the present invention. .

First, as shown in Fig. 1 (a), the substrate 10 (process A) is prepared, and a wiring layer 13 is formed on the surface (first main surface) 10a of the substrate 10 with the insulating layer 11 interposed therebetween. As the substrate 10, for example, a semiconductor substrate such as bismuth (Si) can be used. In the present embodiment, the wiring layer 13 can use a wiring layer formed of Al, an Al alloy, or Cu. As the insulating layer 11, for example, a hafnium oxide film or the like can be used. In the present embodiment, the adhesion layer 12 is formed between the insulating layer 11 and the wiring layer 13, but the adhesion layer 12 may not be formed. As the adhesion layer 12, for example, a layer formed of a material such as titanium (Ti) or titanium nitride (TiN) can be used.

Next, as shown in (b) of FIG. 1, the back surface (second main surface) 10b of the substrate 10 is selectively etched, and the insulating layer 11 and the adhesion layer 12 are formed to penetrate in the thickness direction and have the wiring layer 13 The through hole (through hole) 20 of the exposed bottom portion 20a (process B). At this time, in order to support the substrate 10, the support 30 is attached to the surface 10a side of the substrate 10 with an adhesive layer (not shown) interposed therebetween. For example, the photoresist pattern 40 is formed on the back surface 10b of the substrate 10, and then the photomask is used as a mask, and the substrate 10 is selectively etched by dry etching such as non-isotropic. In the present embodiment, the through hole 20 penetrating the adhesion layer 12 in the thickness direction is also formed. However, a part of the adhesion layer 12 may be left, and the through hole 20 may be formed. In this case, the through hole 20 has a bottom, and the wiring layer 13 is located below the bottom.

Next, as shown in (c) of FIG. 1, after the photoresist pattern 40 is removed, the insulating film 14 is formed on the bottom surface and the side surface of the via hole 20 and the back surface 10b of the substrate 10. For example, the insulating film 14 can be formed by forming a hafnium oxide film, a tantalum nitride film, or the like by a CVD (Chemical Vapor Deposition) method. In the case where the substrate 10 is an insulating substrate, the process of forming the insulating film 14 can be omitted.

Next, as shown in (a) of Fig. 2, the insulating film 14 formed on the bottom portion 20a of the via hole 20 is selectively removed, and the wiring layer 13 is exposed at the bottom portion 20a of the via hole 20. For example, the insulating film 14 can be selectively removed by dry etching such as anisotropic. It should be noted that, in the process (B) shown in (b) of FIG. 1, a part of the adhesion layer 12 is left at the bottom of the through hole 20, and the insulating film 14 can be removed while removing the remaining Tight adhesion layer 12.

Next, as shown in FIG. 2(b), the first metal layer 15 and the second metal layer 16 are sequentially formed on the bottom surface and the side surface of the via hole 20 and the back surface 10b of the substrate 10 (process C). Here, the first metal layer 15 is formed of a material that forms an alloy with a Sn-based molten metal filled in the through hole 20. As the first metal layer 15, for example, a metal layer formed of a material such as titanium (Ti), titanium nitride (TiN), platinum (Pt), nickel (Ni), or cobalt (Co) can be used. It is to be noted that the thickness of the first metal layer 15 is preferably in the range of 0.01 μm to 1 μm.

The second metal layer 16 is formed of a material that prevents oxidation of the first metal layer 15. As the second metal layer 16, for example, a metal layer formed of a material such as copper (Cu), silver (Ag), gold (Au), platinum (Pt), nickel (Ni), or cobalt (Co) can be used. It is to be noted that Cu, Ag, and Au are preferably used as the material which is easily diffused into the through electrode 17. Preferably, the thickness of the second metal layer 16 is in the range of 0.01 μm to 1 μm.

For example, the first metal layer 15 and the second metal layer 16 can be formed by sputtering. In order not to oxidize the surface of the first metal layer 15, it is preferable to form the first metal layer 15 and the second metal layer 16 continuously. Further, it is preferable that the oxide formed on the surface of the wiring layer 13 exposed at the bottom portion 20a of the through hole 20 is removed by reverse sputtering or the like before the first metal layer 15 is formed.

It should be noted that the first metal layer 15 and the second metal layer 16 may be formed at least at the bottom of the through hole 20. The first metal layer 15 and the second metal layer 16 may be formed on the side surface of the via hole 20 and the surface of the substrate 10, as shown in (b) of FIG.

In the process (B) shown in (b) of FIG. 1, a part of the adhesion layer 12 remains in the bottom of the via hole 20, if the adhesion layer 12 is made of the material used for the first metal layer 15 (for example) When Ti, TiN, etc. are formed, the first metal layer 15 is formed at the bottom of the through hole 20. Therefore, in this case, it is not necessary to form the first metal layer 15 in the process (C). However, after the oxide formed on the surface of the adhesion layer 12 is removed by reverse sputtering or the like, it is necessary to form the second metal layer 16.

Next, as shown in (c) of FIG. 2, a Sn-based molten metal 17 is filled into the via hole 20 (Process D). For example, the molten metal 17 is allowed to flow into the through hole 20 from the opening surface of the through hole 20, and the molten metal 17 is cooled while pressurizing the molten metal 17, whereby the molten metal 17 can be filled. Therefore, a through electrode in which the molten metal 17 is solidified is formed in the through hole 20. It should be noted that the through electrode is denoted by the same reference numeral 17 as the molten metal.

At this time, the metal in the second metal layer 16 that is in contact with the through electrode 17 is diffused into the through electrode 17 and alloyed with tin in the through electrode 17 . As a result, as shown in (d) of FIG. 2, the wiring layer 13 exposed at the bottom portion 20a of the via hole 20 is in contact with the through electrode 17 via the first metal layer 15.

Here, the Sn-based molten metal 17 is a molten metal containing Sn as a main component, and the Sn-based molten metal 17 may be an alloy containing Bi, In, Cu, Ag, Ga, Ni, or the like.

According to the method of manufacturing the wiring structure of the present embodiment, the wiring layer 13 exposed at the bottom portion 20a of the through hole 20 is in contact with the through electrode 17 via the first metal layer 15 formed of a material forming an alloy with Sn. Therefore, even if the process of filling the molten metal into the through hole 20 is not performed under vacuum, the first metal layer 15 whose surface has not been oxidized can be alloyed with the through electrode 17. Therefore, even if the wiring layer 13 is formed using aluminum, it is possible to provide good contact between the wiring layer 13 and the through electrode 17. In the case where the wiring layer 13 is formed of copper, the first metal layer 15 prevents the copper forming the wiring layer 13 from diffusing into the Sn of the through electrode 17. Therefore, it is possible to prevent voids from occurring in the vicinity of the through electrode 17 in the inside of the wiring layer 13. As a result, it is possible to prevent the wiring layer 13 from being poor in conduction.

In the present embodiment, as shown in (d) of FIG. 2, the metal in the second metal layer 16 in contact with the through electrode 17 is diffused into the through electrode 17 and formed with tin in the through electrode 17. Alloy, but a portion of the second metal layer 16 can remain. In this case, the second metal layer 16 does not interfere with the alloying of the first metal layer 15 and the through electrode 17.

(Second embodiment)

In the first embodiment, as shown in FIG. 1(b), when the via hole 20 is formed, the wiring layer 13 is exposed at the bottom portion 20a of the via hole 20. As shown in (b) of FIG. 2, the first metal layer 15 and the second metal layer 16 are formed on the exposed wiring layer 13. That is, the structure is such that the first metal layer 15 and the second metal layer 16 are formed on the wiring layer 13 before the Sn-based molten metal 17 is filled into the via hole 20.

The second embodiment of the present invention adopts a structure in which the first metal layer 18 and the second metal layer 19 which are in contact with the wiring layer 13 are formed before the via holes 20 are formed.

Hereinafter, a method of manufacturing the wiring structure according to the second embodiment of the present invention will be described with reference to (a) to (c) of FIG. 3, (a) of FIG. 4, and (c) of FIG. In the same manner, the same portions as those in the first embodiment are denoted by the same reference numerals, and the detailed description thereof will be omitted.

First, as shown in FIG. 3(a), the substrate 10 (process A) is prepared, and on the surface (first main surface) 10a of the substrate 10, a close adhesion layer 12 is formed in this order with the insulating layer 11 interposed therebetween. The second metal layer 19, the first metal layer 18, and the wiring layer 13. The substrate 10 is, for example, a semiconductor substrate such as germanium (Si), but is not limited thereto.

In the present embodiment, the wiring layer 13 can use a wiring layer formed of Al, an Al alloy, or Cu. The first metal layer 18 is formed of a material that forms an alloy with a Sn-based molten metal. As the first metal layer 18, for example, a metal layer formed of a material such as titanium (Ti), titanium nitride (TiN), platinum (Pt), nickel (Ni), or cobalt (Co) can be used. The second metal layer 19 is formed of a material that prevents oxidation of the first metal layer 18. As the second metal layer 19, for example, a metal layer formed of a material such as copper (Cu), silver (Ag), or gold (Au) can be used. In this case, when the via hole is formed by etching, it is preferable to select it relatively large.

The second metal layer 19, the first metal layer 18, and the wiring layer 13 can be formed, for example, by a sputtering method. It should be noted that the adhesion layer 12, the second metal layer 19, the first metal layer 18, and the wiring layer 13 are preferably formed continuously.

Preferably, the thickness of the first metal layer 18 is in the range of 0.01 μm to 1 μm. Preferably, the thickness of the second metal layer 19 is in the range of 0.01 μm to 1 μm. As the insulating layer 11, for example, a hafnium oxide film or the like can be used. As the adhesion layer 12, for example, a film formed of a material such as titanium (Ti) or titanium nitride (TiN) can be used. Incidentally, in the present embodiment, the adhesion layer 12 is formed between the insulating layer 11 and the second metal layer 19, but the adhesion layer 12 may not be provided.

Next, as shown in (b) of FIG. 3, the back surface (second main surface) 10b of the substrate 10 is selectively etched to form the insulating layer 11 and the adhesion layer 12 in the thickness direction and has the second metal A through hole (through hole) 20 of the bottom portion 20a exposed by the layer 19 (process B). At this time, in order to support the substrate 10, the support 30 is attached to the surface 10a side of the substrate 10 with an adhesive layer (not shown) interposed therebetween. For example, the photoresist pattern 40 can be formed on the back surface 10b of the substrate 10, and then used as a photomask to selectively etch the substrate 10 by dry etching such as non-isotropic. In addition, in the present embodiment, the through hole 20 penetrating the adhesion layer 12 in the thickness direction is also formed, but a part of the adhesion layer 12 may be left, and the through hole 20 may be formed. In this case, the through hole 20 has a bottom, and the second metal layer 19 is located below the bottom.

Next, as shown in (c) of FIG. 3, after the photoresist pattern 40 is removed, the insulating film 14 is formed on the bottom surface and the side surface of the via hole 20 and the back surface 10b of the substrate 10. For example, the insulating film 14 can be formed by forming a hafnium oxide film, a tantalum nitride film, or the like by a CVD (Chemical Vapor Deposition) method.

Next, as shown in (a) of FIG. 4, the insulating film 14 formed at the bottom of the via hole 20 is selectively removed, and the second metal layer 19 is exposed at the bottom portion 20a of the via hole 20. In addition, in the process (B) shown in (b) of FIG. 3, if a part of the adhesion layer 12 is left at the bottom of the through hole 20, the insulating film 14 is removed, and the residue is also left. The adhesion layer 12 is removed.

Next, as shown in (b) of Fig. 4, a Sn-based molten metal 17 is filled into the via hole 20 (Process C). For example, the molten metal 17 is allowed to flow into the through hole 20 from the opening surface of the through hole 20, and the molten metal 17 is cooled while pressurizing the molten metal 17, whereby the molten metal 17 can be filled. Therefore, a through electrode in which the molten metal 17 is solidified is formed in the through hole 20. It should be noted that the through electrode is denoted by the same reference numeral 17 as the molten metal.

At this time, the metal in the second metal layer 19 that is in contact with the through electrode 17 is diffused into the through electrode 17 and alloyed with tin in the through electrode 17 . As a result, as shown in (c) of FIG. 4, the wiring layer 13 located under the bottom of the via hole 20 is in contact with the through electrode 17 via the first metal layer 18.

Here, the Sn-based molten metal 17 is a molten metal containing Sn as a main component, and the Sn-based molten metal 17 may be an alloy containing Bi, In, Cu, Ag, Ga, Ni, or the like.

According to the method of manufacturing the wiring structure of the present embodiment, the wiring layer 13 located below the bottom of the via hole 20 is in contact with the through electrode 17 via the first metal layer 18 formed of a material forming an alloy with Sn. Therefore, even if the process of filling the molten metal into the through hole 20 is not performed under vacuum, the first metal layer 18 whose surface has not been oxidized can be alloyed with the through electrode 17. Therefore, even if the wiring layer 13 is formed using aluminum, it is possible to provide good contact between the wiring layer 13 and the through electrode 17. In the case where the wiring layer 13 is formed of copper, the first metal layer 18 can prevent the copper of the wiring layer 13 from diffusing into the Sn of the through electrode 17. Therefore, it is possible to prevent voids from occurring in the vicinity of the through electrode 17 in the inside of the wiring layer 13. As a result, it is possible to prevent the wiring layer 13 from being poor in conduction. Moreover, since the first metal layer 18 and the second metal layer 19 can be simultaneously formed in the process of forming the wiring layer 13, the manufacturing process of the wiring structure can be simplified.

In the present embodiment, as shown in FIG. 4( c ), the formation metal of the second metal layer 19 that is in contact with the through electrode 17 is diffused into the through electrode 17 and formed with tin in the through electrode 17 . Alloy, but a portion of the second metal layer 19 can remain. In this case, the second metal layer 19 does not interfere with the alloying of the first metal layer 18 and the through electrode 17.

(filling method of Sn-based molten metal)

Referring to (a) of FIG. 5, (b) of FIG. 5, (a) of FIG. 6, and (b) of FIG. 6, the filling of the Sn-based molten metal into the through hole 20 of the present embodiment will be described. method. Of course, in the present embodiment, the filling method of the Sn-based molten metal is not limited thereto.

(a) of FIG. 5 is a view showing an outline of a filling device for molten metal.

As shown in (a) of FIG. 5, the filling device of the molten metal includes a support portion 50 that supports the substrate 10, a cylindrical portion 60 that is arranged to surround the periphery of the substrate 10, and an inner side that is in close contact with the cylindrical portion 60. The pressurizing portion 70 is provided. The pipe 81 that communicates with the container 80 in which the molten metal 82 is housed penetrates the tubular portion 60 in the radial direction. The support portion 50 and the pressurizing portion 70 are controlled by the drive portions 51 and 71, respectively, and are movable up and down. It should be noted that, as shown in (b) of FIG. 2 or (a) of FIG. 4, the through hole 20 is formed in the substrate 10.

(b) of FIG. 5 shows a state in which the support portion 50 of the support substrate 10 is raised toward the tubular portion 60 and the upper surface of the substrate 10 is placed on the lower surface of the tubular portion 60. Therefore, the processing chamber 100 defined by the tubular portion 60 and the pressurizing portion 70 is formed. It should be noted that the airtightness of the processing chamber 100 is ensured by the sealing members 90 and 91. The volume of the processing chamber 100 is adjusted by moving the pressurizing portion 70 up and down.

(a) of FIG. 6 is a partially enlarged view showing a state in which the molten metal 82 accommodated in the container 80 is supplied to the processing chamber 100 via the pipe 81 in the state shown in (a) of FIG. 5 . At this time, the molten metal 82 supplied to the process chamber 100 is filled to the inside of the through hole 20 formed on the substrate 10. It should be noted that the portions other than the through holes 20 formed in the substrate 10 are omitted here. By pressurizing the molten metal 82 in the processing chamber 100 by the pressurizing portion 70, the molten metal 82 can be efficiently filled in the bottom portion of the through hole 20. When the molten metal 82 is cooled while pressurizing the molten metal 82, the through electrode 17 in which the molten metal 82 is solidified is formed in the through hole 20 as shown in FIG. 6(b). In addition, (b) of FIG. 6 shows a state in which the molten metal 82 solidified on the surface of the substrate 10 has been removed, but a part of the molten metal 82 may be left and connected to the through electrode 17. Wiring layer.

The present invention has been described above by way of preferred embodiments, and the above description is not a limitation, and various changes can of course be made. For example, in the above-described embodiment, the semiconductor substrate such as Si is exemplified as the substrate 10, but the invention is not limited thereto. For example, it may be an insulating substrate such as glass or resin. In this case, the process of forming the insulating film 14 on the inner surface or the like of the via hole 20 shown in (c) of FIG. 1 and (c) of FIG. 3 can be omitted.

Claims (9)

 A manufacturing method of a wiring structure, comprising: a process (A) for preparing a substrate having a wiring layer formed on the first main surface with an insulating layer interposed therebetween; and a process (B) for selectively etching the substrate a through hole penetrating through the insulating layer in a thickness direction and having a bottom portion, wherein the wiring layer is located below the bottom portion; and a process (C) of the wiring corresponding to at least a bottom portion of the through hole Forming a first metal layer and a second metal layer in sequence; and a process (D) filling the Sn-type molten metal into the through hole; the wiring layer being formed of Al, an Al alloy or Cu; the first metal layer being The above process (D) is formed of a material which forms an alloy with the aforementioned Sn-based molten metal; and the second metal layer is formed of a material which prevents oxidation of the first metal layer.    The method of manufacturing a wiring structure according to claim 1, wherein the first metal layer and the second metal layer are continuously formed in the process (C).    The manufacturing method of the wiring structure according to claim 1 or 2, wherein a dense adhesion layer is further formed between the insulating layer and the wiring layer; and a through hole is formed in the process (B), the through hole being at least in a thickness direction The insulating layer is penetrated and has a bottom portion, and the wiring layer is located below the bottom portion.    The method of manufacturing a wiring structure according to claim 1 or 2, wherein the first metal layer is formed of a material selected from the group consisting of Ti, TiN, Pt, Ni, and Co.    The method of manufacturing a wiring structure according to claim 1 or 2, wherein the second metal layer is formed of a material selected from the group consisting of Cu, Ag, Au, Pt, Ni, and Co.    A manufacturing method of a wiring structure, comprising: a process (A), preparing a substrate, sequentially forming a second metal layer, a first metal layer, and a wiring layer on a first main surface of the substrate with an insulating layer interposed therebetween; B) selectively etching a second main surface of the substrate to form a via hole penetrating the insulating layer and having a bottom portion, the wiring layer being located below the bottom portion; and a process (C) for classifying a Sn metal Filled into the through hole; the wiring layer is formed of Al, an Al alloy or Cu; the first metal layer is formed of a material forming an alloy with the Sn-based molten metal in the process (C); the second metal layer Formed by a material that prevents oxidation of the aforementioned first metal layer.    The manufacturing method of the wiring structure according to claim 6, wherein a close adhesion layer is further formed between the insulating layer and the second metal layer; and a through hole is formed in the process (B), the through hole is at least in a thickness direction The insulating layer is penetrated and has a bottom portion, and the second metal layer is located below the bottom portion.    The method of manufacturing a wiring structure according to claim 6 or 7, wherein the first metal layer is formed of a material selected from the group consisting of Ti, TiN, Pt, Ni, and Co.    The method of manufacturing a wiring structure according to claim 6 or 7, wherein the second metal layer is formed of a material selected from the group consisting of Cu, Ag, Au, Pt, Ni, and Co.