JP2006108182A - Semiconductor device, mounted body thereof, and manufacturing method thereof - Google Patents

Abstract

【Task】
Provided is a semiconductor device including a columnar electrode having a ball-shaped low melting point layer bonded only near the upper surface of a columnar portion.
[Solution]
After the columnar portion 22 is formed of aluminum or titanium and the oxide film 23 is formed on the side surface of the columnar portion 22, the low melting point layer 24 is reflowed to obtain a ball shape. Prevent side surface wetting of the melting point layer. The oxide film 23 may be formed by a method of heating the columnar electrode 20 in an oxygen atmosphere or by a method of forming a natural oxide film by leaving the columnar electrode 20 for several hours to several days.
[Selection] Figure 9

Description

  The present invention relates to a semiconductor device, a mounting body thereof, and a manufacturing method thereof, and more particularly to a semiconductor device effective for narrowing the pitch, a mounting body thereof, and a manufacturing method thereof.

  Along with the demand for miniaturization of integrated circuits, the structure of a semiconductor device is configured to be as close as possible to a bare chip, as represented by CSP (Chip Size Package), and this semiconductor device is bonded to a wiring board by flip-chip mounting. The technique to do is attracting attention.

  Here, the bonding between the semiconductor device and the wiring board by the flip-chip mounting is performed via bumps provided on the main surface side of the semiconductor substrate constituting the semiconductor device. The bumps are arranged at a narrow pitch. Therefore, it is necessary to reduce the volume of the bumps and avoid contact between adjacent bumps.

  However, if the volume of the bump is reduced, the gap between the semiconductor substrate and the wiring substrate becomes smaller, so that it is difficult to underfill the resin in the gap for the purpose of stabilizing the bonding, improving the connection reliability, or ensuring it. Become.

Therefore, in order to ensure the above gap, conventionally, a bonding bump using a post-like metal pillar has been studied. As a semiconductor device using this type of post-type bonding bump and a mounting method thereof, for example, The literature is known.
JP-A-5-136201 JP 2002-313993 A US Pat. No. 6,592,019 Here, in the above-mentioned patent document 1, as shown in paragraph 0020 of FIG. 1 and FIG. 1, a bonding bump having a metal column is formed by a wire bonding method. A technique is disclosed.

  Further, in Patent Document 2, as shown in paragraphs 0002 to 0007 and FIGS. 18 to 24 of the same document, a metal column is formed by a plating method, and a solder ball is provided on the upper surface of the metal column. A method of forming bumps is disclosed.

  In Patent Document 3, as shown in the seventh column, lines 16 to 54 and FIGS. 1 to 3 of the same document, a metal column and a solder layer are formed on the upper surface thereof by plating. There are disclosed a method of bonding the solder layer to the wiring substrate as it is, and a method of bonding the solder layer once to a ball shape by reflow and bonding to the wiring substrate.

  However, in the method disclosed in Patent Document 1, since it is necessary to form a wire bump for each terminal, it becomes difficult to apply to a semiconductor device having a large number of input / output terminals, and the height of each bump is reduced. It is difficult to align them, and it is considered difficult to apply to recent multi-pin narrow pitch type semiconductor devices.

  Further, in the technique disclosed in Patent Document 2, the process in which the upper surface of the metal column is covered with resin occurs as shown in Paragraph 0007 and FIG. 22 of the same document. Since it is necessary to polish the metal pillar to create the state shown in FIG. 23, and the semiconductor device is configured with the metal pillar embedded in the resin, there is a problem that an underfill gap cannot be secured. .

  On the other hand, in the method disclosed in Patent Document 3, the metal pillar and the solder layer are formed by plating, and the metal pillar is mounted on the wiring board in an exposed state. This is considered to be a very good technique in terms of securing the fill gap.

  However, in Patent Document 3, as shown in the seventh column, lines 47 to 53 of the same document, it occurs when the solder layer formed on the upper surface of the metal column is reflowed to form solder balls. Although various problems have been mentioned, further studies were necessary to form solder balls on metal columns with high accuracy.

  Therefore, the present invention provides a semiconductor device effective for forming a bonding bump having a solder ball on the upper surface of a columnar portion, a mounting body thereof, and a manufacturing method thereof.

  In order to achieve the above object, according to a first aspect of the present invention, there is provided a semiconductor device including a plurality of columnar electrodes provided on a semiconductor substrate, wherein the columnar electrodes include a columnar portion formed of a conductive material and the columnar portion. And a metal ball portion formed of a conductive material having a low melting point and bonded to the upper surface of the columnar portion, and the conductive material constituting the columnar portion includes aluminum and / or titanium.

  As described above, the columnar portion is made of a conductive material containing aluminum and / or titanium, so that the oxide film is less likely to get wet by low melting point materials such as solder compared to the case where the columnar portion is made of nickel or copper. Therefore, when the ball portion is formed by reflow of the low melting point material, wetting of the low melting point material onto the side surface of the columnar portion can be prevented.

  As a result, the height of each columnar electrode is made uniform, so that the bonding accuracy of each electrode to the wiring board is improved, and the electrode pitch is made as narrow as possible while ensuring an underfill gap. Realization is possible.

  According to a second aspect of the present invention, in the semiconductor device including a plurality of columnar electrodes provided on a semiconductor substrate, the columnar electrode includes a first conductive material containing nickel and / or copper, aluminum and / or titanium. A columnar portion formed by bonding a second conductive material including a metal ball portion formed of a conductive material having a melting point lower than that of the columnar portion and bonded to the upper surface of the columnar portion; The second conductive material is arranged near the upper surface of the columnar part.

  In this way, by forming the second conductive material containing aluminum and / or titanium that can provide an oxide film suitable for preventing wetting of the low melting point material in the vicinity of the upper surface, when forming a ball by reflow of the low melting point material, It is possible to prevent the low melting point material from getting wet on the side surface of the columnar part.

  The invention according to claim 3 is the invention according to claim 2, wherein the columnar portion includes a first layer formed of the first conductive material, and the second layer on the first layer. And a second layer made of a conductive material, wherein the metal ball portion is formed on the second layer.

  Thus, by forming the upper surface of the columnar electrode with the second conductive material, an oxide film suitable for preventing the low melting point material from getting wet can be obtained near the upper surface of the columnar part. Sometimes, the low melting point material can be prevented from getting wet to the side surface of the columnar part.

  According to a fourth aspect of the present invention, in the second aspect of the present invention, the columnar portion includes a first layer formed of the first conductive material, and the second layer on the first layer. A second layer formed of a conductive material; and a third layer formed of the first conductive material on the second layer. The metal ball portion is formed on the third layer. It is characterized by being formed.

  As described above, even when the upper surface of the columnar electrode is formed of the first conductive material, the second conductive material is arranged in the vicinity of the upper surface, so that the oxidation suitable for preventing wetting of the low melting point material is achieved. Since the film is obtained in the vicinity of the upper surface of the columnar part, wetting of the low melting point material onto the side surface of the columnar part can be prevented during ball formation by reflow of the low melting point material.

  According to a fifth aspect of the present invention, in the semiconductor device including a plurality of columnar electrodes provided on a semiconductor substrate, the columnar electrode includes a columnar portion formed of a conductive material and a conductive material having a melting point lower than that of the columnar portion. A metal ball portion formed of a material and bonded to the upper surface of the columnar portion, and a wetting prevention formed on the side surface of the columnar portion formed of a material having low wettability with respect to the conductive material constituting the ball portion. And the ball part is joined only near the upper surface of the columnar part.

  In this way, by forming the wetting prevention part on the side surface of the columnar part, the low melting point material becomes difficult to flow to the side surface of the columnar part. Therefore, when the ball is formed by reflow of the low melting point material, the side surface of the columnar part of the low melting point material Wetting can be prevented.

  According to a sixth aspect of the present invention, in the semiconductor device including a plurality of columnar electrodes provided on a semiconductor substrate, the columnar electrode includes a columnar portion formed of a conductive material and a conductive material having a melting point lower than that of the columnar portion. A metal ball portion formed of a material and bonded to the upper surface of the columnar portion, and a material having low wettability with respect to the conductive material constituting the metal ball portion, and selected on a side surface near the upper surface of the columnar portion. And an anti-wetting part applied thereto.

  Thus, by selectively forming the wetting prevention portion on the side surface near the upper surface of the columnar portion, the low melting point material is less likely to flow to the side surface of the columnar portion. It is possible to prevent the melting point material from getting wet on the side surface of the columnar part.

  According to a seventh aspect of the present invention, in the semiconductor device including a plurality of columnar electrodes provided on a semiconductor substrate, the columnar electrode includes a columnar portion formed of a conductive material and a conductive material having a melting point lower than that of the columnar portion. A metal ball portion formed of a material and bonded to the upper surface of the columnar portion, and a wetting prevention portion formed by processing the shape of the side surface of the columnar portion are provided.

  In this way, by processing the shape of the side surface of the columnar portion, the low melting point material is less likely to flow to the side surface of the columnar portion. Therefore, when the ball is formed by reflow of the low melting point material, Wetting can be prevented.

  According to an eighth aspect of the present invention, in the semiconductor device including a plurality of columnar electrodes provided on a semiconductor substrate, the columnar electrode includes a columnar portion formed of a conductive material and a conductive material having a melting point lower than that of the columnar portion. A metal ball portion formed of a material and bonded to the upper surface of the columnar portion; and a shape processing portion formed by processing the shape of the upper surface of the columnar portion.

  In this way, by processing the shape of the upper surface of the columnar portion, the tension to the low melting point material is increased, and as a result, the low melting point material is less likely to flow to the side surface of the columnar portion. Sometimes, the low melting point material can be prevented from getting wet on the side surface of the columnar part.

  The invention according to claim 9 is a mounting body of a semiconductor device in which a semiconductor device provided with a plurality of columnar electrodes provided on a semiconductor substrate is mounted on a wiring substrate via each columnar electrode. A columnar portion made of a conductive material, and a low melting point metal layer formed of a conductive material having a melting point lower than that of the columnar portion and bonded to the upper surface of the columnar portion, and constituting the columnar portion. The material is characterized in that it contains aluminum and / or titanium.

  As described above, the columnar portion is made of a conductive material containing aluminum and / or titanium, so that the oxide film is less likely to get wet by low melting point materials such as solder compared to the case where the columnar portion is made of nickel or copper. Therefore, when the ball portion is formed by reflow of the low melting point material, wetting of the low melting point material onto the side surface of the columnar portion can be prevented.

According to a tenth aspect of the present invention, there is provided a semiconductor device mounting body in which a semiconductor device including a plurality of columnar electrodes provided on a semiconductor substrate is mounted on a wiring substrate via each columnar electrode.
The columnar electrode includes a columnar portion formed by joining a first conductive material containing nickel and / or copper and a second conductive material containing aluminum and / or titanium, and has a melting point higher than that of the columnar portion. A low-melting-point metal layer formed of a low conductive material and bonded to the upper surface of the columnar portion, wherein the second conductive material is disposed near the upper surface of the columnar portion.

  In this way, by forming the second conductive material containing aluminum and / or titanium that can provide an oxide film suitable for preventing wetting of the low melting point material in the vicinity of the upper surface, when forming a ball by reflow of the low melting point material, It is possible to prevent the low melting point material from getting wet on the side surface of the columnar part.

  The invention according to claim 11 is a mounting body of a semiconductor device in which a semiconductor device provided with a plurality of columnar electrodes provided on a semiconductor substrate is mounted on a wiring substrate via each columnar electrode. A columnar part made of a conductive material, a low melting point metal layer formed of a conductive material having a melting point lower than that of the columnar part and bonded to the upper surface of the columnar part, and a conductive material constituting the low melting point metal layer And a wetting prevention portion selectively formed on a side surface near the upper surface of the columnar portion.

  Thus, by selectively forming the wetting prevention portion on the side surface near the upper surface of the columnar portion, the low melting point material is less likely to flow to the side surface of the columnar portion. It is possible to prevent the melting point material from getting wet on the side surface of the columnar part.

  According to a twelfth aspect of the present invention, there is provided a mounting body of a semiconductor device in which a semiconductor device having a plurality of columnar electrodes provided on a semiconductor substrate is mounted on a wiring substrate via each columnar electrode. A columnar portion formed of a conductive material, a low melting point metal layer formed of a conductive material having a melting point lower than that of the columnar portion and bonded to the upper surface of the columnar portion, and a shape of a side surface of the columnar portion. And a wetting prevention portion formed in the above manner.

  In this way, by processing the shape of the side surface of the columnar portion, the low melting point material is less likely to flow to the side surface of the columnar portion. Therefore, when the ball is formed by reflow of the low melting point material, Wetting can be prevented.

  According to a thirteenth aspect of the present invention, there is provided a mounting body of a semiconductor device in which a semiconductor device having a plurality of columnar electrodes provided on a semiconductor substrate is mounted on a wiring substrate via each columnar electrode. A columnar portion formed of a conductive material, a low melting point metal layer formed of a conductive material having a melting point lower than that of the columnar portion and bonded to the upper surface of the columnar portion, and a shape of the upper surface of the columnar portion. And a shape processing portion formed in the above manner.

  In this way, by processing the shape of the upper surface of the columnar portion, the tension to the low melting point material is increased, and as a result, the low melting point material is less likely to flow to the side surface of the columnar portion. Sometimes, the low melting point material can be prevented from getting wet to the side surface of the columnar part.

  According to a fourteenth aspect of the present invention, in a method of manufacturing a semiconductor device including a plurality of columnar electrodes provided on a semiconductor substrate, a step of forming a columnar portion made of a conductive material on an electrode pad of the semiconductor substrate; A step of forming a low melting point layer made of a conductive material having a melting point lower than that of the columnar portion on the upper surface of the columnar portion, a step of performing a side surface treatment of the columnar portion after forming the low melting point layer, and the side surface treatment. And a step of melting the low melting point layer to form a ball-shaped low melting point layer.

  Thus, by performing the side treatment of the columnar portion after forming the low melting point layer, after the side treatment is performed in a state where the low melting point layer is well bonded to the upper surface of the columnar portion, the side treatment is performed. By melting the low melting point layer to form a ball-like low melting point layer, wetting of the low melting point layer to the side surface of the columnar part can be prevented.

  As described above, according to the present invention, it is possible to form a columnar electrode having a ball portion joined only near the upper surface of the columnar portion.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The present invention is not limited to the embodiments described below, and can be modified as appropriate.

  FIG. 1 is a cross-sectional view showing a mounting structure of a semiconductor device according to this embodiment. As shown in the figure, the present mounting structure has a structure in which the semiconductor device 10 is mounted on the wiring board 30 via the columnar electrodes 20.

  The semiconductor device 10 is formed with a semiconductor substrate 12 made of silicon, a plurality of aluminum electrode pads 14 provided on the main surface side of the semiconductor substrate 12, and the electrode pads 14 partially exposed. And a passivation film 16.

  The columnar electrode 20 is composed of a columnar portion 22 made of copper formed on the exposed portion of each electrode pad 14 and a low melting point layer 24 made of solder formed on the upper surface of the columnar portion 22. The columnar portion is preferably formed with a height of 15 μm or more.

  The wiring board 30 includes a multilayer board 32 in which various patterns are layered, and a wiring pattern 34 formed on the surface of the multilayer board 32.

  The electrical connection between the semiconductor device 10 and the wiring substrate 30 is performed by melting the low melting point layer 24 located at the tip of the columnar electrode 20 on the wiring pattern 34, and the semiconductor device 10 and the wiring substrate 30 are connected to each other. In the meantime, underfill 40 is applied to protect the joined state of each columnar electrode 20.

  FIG. 2 is a cross-sectional view showing a first manufacturing process of the semiconductor device according to this embodiment. When manufacturing the semiconductor device according to the present embodiment, first, as shown in FIG. 2A, a plurality of electrode pads 14 are formed on the main surface side of a wafer 13 on which a plurality of integrated circuits are formed. A passivation film 16 is formed in a state where the central portion of each electrode pad 14 is exposed.

  Subsequently, as shown in FIG. 4B, a photoresist 42 is applied on the passivation film 16, and then, as shown in FIG. 4C, the photoresist is applied corresponding to the exposed portion of each electrode pad 14. 42 is exposed to form an opening 44 that exposes each electrode pad 14. Here, the width of each opening 14 is narrower than the opening width of the passivation film 16, and each opening 14 is formed without touching the end of the passivation film 16.

  FIG. 3 is a cross-sectional view showing a second manufacturing process of the semiconductor device according to this embodiment. As shown in FIG. 2A, the columnar portion 22 is formed on the electrode pad 14 using the opening 44 shown in the previous figure. The columnar portion 22 is formed by copper plating.

  Subsequently, as shown in FIG. 4B, the low melting point layer 24 is formed on the upper surface of the columnar portion 22 by using the opening 44 shown in the previous figure. The low melting point layer 24 is formed by solder plating.

  FIG. 4 is a cross-sectional view showing a third manufacturing process of the semiconductor device according to this embodiment. As shown in FIG. 6A, the photoresist 42 shown in the previous figure is removed to obtain a plurality of columnar electrodes 20 formed on the wafer 13. Thereafter, as shown in FIG. 2B, the low melting point layer 24 is heated and melted to process the low melting point layer 24 into a ball shape. This heat melting process is performed by putting the wafer 13 into a reflow furnace and performing a heat treatment at a predetermined temperature and time. Prior to reflow, an oxide film removing agent is applied.

  FIG. 5 is a cross-sectional view showing a first mounting process of the semiconductor device according to this embodiment. As shown in the figure, when the semiconductor device 10 manufactured through the series of steps described above is mounted on the wiring board 30, the main surface side of the semiconductor device 10 faces the wiring board 30, and the columnar electrode 20 The ball-shaped low melting point layer 24 located at the tip and the wiring pattern provided on the wiring substrate 30 are aligned.

  FIG. 6 is a cross-sectional view showing a second mounting step of the semiconductor device according to this embodiment. As shown in the figure, the semiconductor device 10 aligned in the process shown in the previous figure is mounted on the wiring board 30 and then reflowed to melt and fix the low melting point layer 24 on the wiring pattern 34. After the fixing of the low melting point layers 24 is completed, the structure shown in FIG. 1 is obtained by filling the underfill resin from the direction indicated by the arrow A in FIG.

  FIG. 7 is a cross-sectional view showing another mounting structure of the semiconductor device according to the present embodiment. As shown in the figure, as long as the semiconductor device 10 is mounted on the wiring substrate 30, the end of the columnar portion 22 may be embedded in the low melting point layer 24.

  FIG. 8 is a cross-sectional view showing a state of a columnar electrode having low connection reliability. As shown in FIG. 4A, when the ball-shaped low melting point layer 24 is formed in contact with the side surface of the columnar portion 22, the height of each columnar electrode 22 varies. As a result, as shown in FIG. As shown in (b), columnar electrodes that are not joined to the wiring pattern 34 are generated.

  In order to prevent this state, in the present embodiment, the method described below is applied in the step of forming the ball-shaped low melting point layer 24 shown in FIG.

  FIG. 9 is a cross-sectional view showing a first configuration example of the columnar electrode effective for preventing wetting of the side surface of the columnar portion. In order to prevent wetting on the side surface of the columnar portion, as shown in FIG. 5A, the columnar portion 22 is formed of aluminum or titanium, and after the oxide film 23 is formed on the side surface of the columnar portion 22, It is effective to use a reflow of the melting point layer 24 to obtain a ball shape and to prevent the low melting point layer from being wetted on the side surface using the oxide film. The oxide film 23 may be formed by a method of heating the columnar electrode 20 in an oxygen atmosphere or by a method of forming a natural oxide film by leaving the columnar electrode 20 for several hours to several days.

  In addition, as shown in FIG. 2B, the columnar portion 22 has a two-layer structure of a first layer 22-1 made of nickel or copper and a second layer 22-2 made of aluminum or titanium, A method of preventing side surface wetting by using the oxide film 23 formed on the side surface of the second layer 22-2 by bonding the low melting point layer 24 to the upper surface of the layer 22-2 is also effective.

  In addition, as shown in FIG. 2C, the columnar portion 22 is configured by using a first layer 22-1 made of nickel or copper and a second layer 22-2 made of aluminum or titanium, An oxide film formed on the side surface of the second layer 22-2 by interposing the layer 22-2 near the upper surface of the columnar portion and bonding the low melting point layer 24 to the upper surface of the first layer 22-1 A method of using 23 to prevent side wetting is also effective. The layer structure shown in the figure can be formed by alternately growing the first layer and the second layer.

  FIG. 10 is a cross-sectional view illustrating a second configuration example of the columnar electrode effective for preventing wetting of the side surface of the columnar portion. In addition to the first configuration example shown in the previous figure, an oxide film, an organic film, or a low melting point layer 24 is formed on the side surface of the columnar portion 22 where the low melting point layer 24 is formed, as shown in FIG. It is also effective to obtain a ball shape by reflowing the low melting point layer 24 after adding the wetting prevention portion 26 made of a material having low wettability to the material to be made.

  The wetting prevention portion 26 is formed by, for example, a method of leaving only around the columnar portion 22 when removing the photoresist 42 shown in FIG. 3B, or after removing the photoresist 42. It can be formed by a method of applying an organic substance. The wetting prevention portion 26 may be removed or left as it is after the ball shape is formed.

  Further, as shown in FIG. 5B, it is also effective to obtain a ball shape by selectively adding the wetting prevention portion 26 only to the side surface near the upper surface of the columnar portion 22 and then performing the reflow of the low melting point layer 24. It is. In the case of selectively forming the wetting prevention portion 26 in this way, the photoresist 42 shown in FIG. 3B is removed by leaving only the side surface near the upper surface, or after the photoresist 42 is removed. It can be formed by a method of selectively applying another organic substance or a method of leaving only the side surface in the vicinity of the upper surface by etching after coating over the entire side surface.

  Also, as shown in FIG. 3C, a method of obtaining a ball shape by reflowing the low melting point layer 24 after selectively adding the wetting prevention portion 26 only to the side surface slightly separated from the upper surface of the columnar portion 22. Is also effective.

  FIG. 11 is a cross-sectional view illustrating a third configuration example of the columnar electrode effective for preventing wetting of the columnar portion side surface. In addition to the first and second configuration examples shown in the previous figure, as shown in FIG. 4A, the side surface near the upper surface of the columnar portion 22 is provided with undulations, and the molten low melting point layer 24 is provided with the undulation portions. It is also effective to prevent the low melting point layer 24 from being wetted on the side surface by making it difficult to flow from side to side.

  Further, as shown in FIG. 4B, the upper surface of the columnar portion 22 is formed in a valley shape, and the molten low melting point layer 24 is less likely to flow to the side surface of the columnar portion 22, so A configuration for preventing the above is also effective.

  Further, as shown in FIG. 3C, the side surface of the low melting point layer 24 is formed by making the upper surface portion of the columnar portion 22 wide and preventing the molten low melting point layer 24 from flowing to the side surface of the columnar portion 22. A configuration for preventing wetting is also effective.

  FIG. 12 is a side view showing a reflow process of the wafer on which the columnar electrodes are formed. As shown in the figure, before melting the low melting point layer 24, the columnar portion 22 of each columnar electrode 20 is formed with the structure shown in FIGS. 9 to 11, and then the wafer on which each columnar electrode 20 is formed. The wafer 13 is placed in the reflow furnace 50 with the back side of 13 placed on the wafer support 52 and the low melting point layer 24 facing upward.

  When the low-melting point layer 24 is heated in this state, downward gravity is applied to the melted low-melting point layer 24, but the columnar part 22 is configured with the above-described structure, so that the side surface of the columnar part 22 is touched. The low-melting point layer 24 is processed into a ball shape in the absence.

  According to the present invention, it is possible to form a columnar electrode having a ball-like low melting point layer joined only near the upper surface of the columnar portion, and therefore, application to a semiconductor device requiring a smaller and narrower pitch is expected. The

It is sectional drawing which shows the mounting structure of the semiconductor device which concerns on this embodiment. It is sectional drawing which shows the 1st manufacturing process of the semiconductor device which concerns on this embodiment. It is sectional drawing which shows the 2nd manufacturing process of the semiconductor device which concerns on this embodiment. It is sectional drawing which shows the 3rd manufacturing process of the semiconductor device which concerns on this embodiment. It is sectional drawing which shows the 1st mounting process of the semiconductor device which concerns on this embodiment. It is sectional drawing which shows the 2nd mounting process of the semiconductor device which concerns on this embodiment. It is sectional drawing which shows another mounting structure of the semiconductor device which concerns on this embodiment. It is sectional drawing which shows the state of a columnar electrode with low connection reliability. It is sectional drawing which shows the 1st structural example of the columnar electrode effective in preventing the wetting to the columnar part side surface. It is sectional drawing which shows the 2nd structural example of the columnar electrode effective in preventing the wetting to the columnar part side surface. It is sectional drawing which shows the 3rd structural example of the columnar electrode effective in preventing the wetting to the columnar part side surface. It is the side view which showed the reflow process of the wafer in which the columnar electrode was formed.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Semiconductor device, 12 ... Semiconductor chip, 13 ... Wafer, 14 ... Electrode pad, 16 ... Passivation film, 20 ... Columnar electrode, 22 ... Columnar part, 23 ... Oxide film, 24 ... Low melting point layer, 26 ... Wetting prevention part , 30 ... Wiring substrate, 32 ... Multilayer substrate, 34 ... Wiring pattern, 40 ... Underfill, 42 ... Photoresist, 44 ... Opening, 50 ... Reflow furnace, 52 ... Wafer support

Claims (14)

In a semiconductor device comprising a plurality of columnar electrodes provided on a semiconductor substrate,
The columnar electrode is
A columnar portion made of a conductive material;
A metal ball portion formed of a conductive material having a melting point lower than that of the columnar portion and bonded to the upper surface of the columnar portion;
The conductive material constituting the columnar portion includes aluminum and / or titanium. In a semiconductor device comprising a plurality of columnar electrodes provided on a semiconductor substrate,
The columnar electrode is
A columnar section formed by joining a first conductive material containing nickel and / or copper and a second conductive material containing aluminum and / or titanium;
A metal ball portion formed of a conductive material having a melting point lower than that of the columnar portion and bonded to the upper surface of the columnar portion;
The semiconductor device, wherein the second conductive material is disposed near the upper surface of the columnar portion. The columnar part is
A first layer formed of the first conductive material; and a second layer formed of the second conductive material on the first layer;
The semiconductor device according to claim 2, wherein the metal ball portion is formed on the second layer. The columnar part is
A first layer formed of the first conductive material; a second layer formed of the second conductive material on the first layer; and the first layer formed on the second layer. A third layer formed of a conductive material,
The semiconductor device according to claim 2, wherein the metal ball portion is formed on the third layer. In a semiconductor device comprising a plurality of columnar electrodes provided on a semiconductor substrate,
The columnar electrode is
A columnar portion made of a conductive material;
A metal ball portion formed of a conductive material having a melting point lower than that of the columnar portion and bonded to the upper surface of the columnar portion;
Formed of a material having low wettability with respect to the conductive material constituting the ball part, and comprising a wetting prevention part applied to the side surface of the columnar part,
2. The semiconductor device according to claim 1, wherein the ball portion is joined only near the upper surface of the columnar portion. In a semiconductor device comprising a plurality of columnar electrodes provided on a semiconductor substrate,
The columnar electrode is
A columnar portion made of a conductive material;
A metal ball portion formed of a conductive material having a melting point lower than that of the columnar portion and bonded to the upper surface of the columnar portion;
And a wetting prevention portion that is formed of a material having low wettability with respect to the conductive material constituting the metal ball portion and is selectively applied to a side surface near the upper surface of the columnar portion. . In a semiconductor device comprising a plurality of columnar electrodes provided on a semiconductor substrate,
The columnar electrode is
A columnar portion made of a conductive material;
A metal ball portion formed of a conductive material having a melting point lower than that of the columnar portion and bonded to the upper surface of the columnar portion;
And a wetting prevention part formed by processing the shape of the side surface of the columnar part. In a semiconductor device comprising a plurality of columnar electrodes provided on a semiconductor substrate,
The columnar electrode is
A columnar portion made of a conductive material;
A metal ball portion formed of a conductive material having a melting point lower than that of the columnar portion and bonded to the upper surface of the columnar portion;
And a shape processing portion formed by processing the shape of the upper surface of the columnar portion. In a semiconductor device mounting body in which a semiconductor device including a plurality of columnar electrodes provided on a semiconductor substrate is mounted on a wiring substrate via each columnar electrode,
The columnar electrode is
A columnar portion made of a conductive material;
A low melting point metal layer formed of a conductive material having a melting point lower than that of the columnar part and bonded to the upper surface of the columnar part;
The conductive material constituting the columnar part includes aluminum and / or titanium. In a semiconductor device mounting body in which a semiconductor device including a plurality of columnar electrodes provided on a semiconductor substrate is mounted on a wiring substrate via each columnar electrode,
The columnar electrode is
A columnar section formed by joining a first conductive material containing nickel and / or copper and a second conductive material containing aluminum and / or titanium;
A low melting point metal layer formed of a conductive material having a melting point lower than that of the columnar part and bonded to the upper surface of the columnar part;
A semiconductor device mounting body, wherein the second conductive material is disposed near an upper surface of the columnar portion. In a semiconductor device mounting body in which a semiconductor device including a plurality of columnar electrodes provided on a semiconductor substrate is mounted on a wiring substrate via each columnar electrode,
The columnar electrode is
A columnar portion made of a conductive material;
A low melting point metal layer formed of a conductive material having a melting point lower than that of the columnar part and bonded to the upper surface of the columnar part;
And a wetting prevention portion that is formed of a material having low wettability with respect to the conductive material constituting the low-melting-point metal layer, and is selectively applied to a side surface near the upper surface of the columnar portion. Device assembly. In a semiconductor device mounting body in which a semiconductor device including a plurality of columnar electrodes provided on a semiconductor substrate is mounted on a wiring substrate via each columnar electrode,
The columnar electrode is
A columnar portion made of a conductive material;
A low melting point metal layer formed of a conductive material having a melting point lower than that of the columnar part and bonded to the upper surface of the columnar part;
And a wetting prevention part formed by processing the shape of the side surface of the columnar part. In a semiconductor device mounting body in which a semiconductor device including a plurality of columnar electrodes provided on a semiconductor substrate is mounted on a wiring substrate via each columnar electrode,
The columnar electrode is
A columnar portion made of a conductive material;
A low melting point metal layer formed of a conductive material having a melting point lower than that of the columnar part and bonded to the upper surface of the columnar part;
And a shape processing part formed by processing the shape of the upper surface of the columnar part. In a method of manufacturing a semiconductor device including a plurality of columnar electrodes provided on a semiconductor substrate,
Forming a columnar portion made of a conductive material on an electrode pad of the semiconductor substrate;
Forming a low melting point layer made of a conductive material having a melting point lower than that of the columnar part on the upper surface of the columnar part;
Performing a side treatment of the columnar portion after forming the low melting point layer;
And a step of melting the low melting point layer to form a ball-shaped low melting point layer after performing the side surface treatment.

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