JP2010040817A - Semiconductor device and manufacturing method thereof - Google Patents

Abstract

In a semiconductor device called CSP, a semiconductor device capable of suppressing unnecessary electromagnetic radiation noise from an integrated circuit on the upper surface side of a silicon substrate to the outside or vice versa, from the outside to an integrated circuit on the upper surface side of the silicon substrate. And a method for manufacturing the same.
A sealing film 10 is formed of a material in which a ferromagnetic powder 10b is mixed in a thermosetting resin 10a. Then, the ferromagnetic powder 10b in the sealing film 10 can suppress unnecessary electromagnetic radiation noise from the upper surface side of the silicon substrate 1 to the outside or vice versa from the outside to the upper surface side of the silicon substrate 1.
[Selection] Figure 1

Description

  The present invention relates to a semiconductor device and a manufacturing method thereof.

  A conventional semiconductor device is called a CSP (chip size package). A plurality of wirings are provided on a semiconductor substrate, a columnar electrode is provided on an upper surface of a connection pad portion of the wiring, and an epoxy is formed on the semiconductor substrate including the wirings. Some sealing films made of a resin or the like are provided such that the upper surface thereof is flush with the upper surface of the columnar electrode, and solder balls are provided on the upper surface of the columnar electrode (see, for example, Patent Document 1).

Japanese Patent Laying-Open No. 2004-342876 (FIG. 6)

  By the way, in the above conventional semiconductor device, the upper surface side of the semiconductor substrate can be protected from contamination and damage from the external atmosphere by the sealing film made of epoxy resin or the like, but from the upper surface side of the semiconductor substrate to the outside Or, conversely, there is a problem that unnecessary electromagnetic radiation noise from the outside to the upper surface side of the semiconductor substrate cannot be suppressed.

  Accordingly, an object of the present invention is to provide a semiconductor device capable of suppressing unwanted electromagnetic radiation noise from the upper surface side of the semiconductor substrate to the outside or vice versa, and from the outside to the upper surface side of the semiconductor substrate, and a method for manufacturing the same. And

According to a first aspect of the present invention, a semiconductor device includes a semiconductor substrate, an integrated circuit provided on the semiconductor substrate, and a plurality of wirings that are electrically connected to the integrated circuit through connection pads. And a protruding electrode provided on the connection pad portion of the wiring, and a material that covers the upper surface of the integrated circuit and that is provided around the protruding electrode and in which a ferromagnetic powder is mixed in a resin. And a sealing film.
A semiconductor device according to a second aspect of the present invention is the semiconductor device according to the first aspect, wherein the wiring is provided on an insulating film provided on the semiconductor substrate, and the insulating film is ferromagnetic in the resin. It consists of a material mixed with body powder.
A semiconductor device according to a third aspect of the present invention is the semiconductor device according to the first or second aspect, wherein the ferromagnetic powder is made of any one of Fe, Co, Ni, and FeNi. It is.
A semiconductor device according to a fourth aspect of the present invention is the semiconductor device according to the first aspect, wherein a solder ball is provided on the protruding electrode.
According to a fifth aspect of the present invention, there is provided a semiconductor device manufacturing method comprising: a plurality of wirings electrically connected to the integrated circuit via connection pads on a semiconductor wafer having a plurality of integrated circuits formed on a main surface thereof; Forming a protruding electrode on the connection pad portion of the wiring, and forming the upper surface of the integrated circuit and around the protruding electrode with a material in which ferromagnetic powder is mixed in a resin. The method includes a step of forming a sealing film and a step of dicing the semiconductor wafer and the sealing film to obtain a plurality of semiconductor devices.
A method of manufacturing a semiconductor device according to a sixth aspect of the present invention is the method according to the fifth aspect, wherein the wiring is formed on the semiconductor substrate, and a material in which a ferromagnetic powder is mixed in a resin. It is characterized by being formed on an insulating film made of.
According to a seventh aspect of the present invention, there is provided a method for manufacturing a semiconductor device according to the fifth or sixth aspect, wherein the ferromagnetic powder is made of any one of Fe, Co, Ni, and FeNi. It is what.
According to an eighth aspect of the present invention, there is provided a method for manufacturing a semiconductor device according to the fifth aspect of the invention, further comprising a step of forming a solder ball on the protruding electrode after the sealing film is formed. It is what.

  According to the present invention, since the sealing film is formed of the material in which the ferromagnetic powder is mixed in the resin, the ferromagnetic powder in the sealing film causes the external circuit from the integrated circuit on the upper surface side of the semiconductor substrate. Therefore, it is possible to suppress unnecessary electromagnetic radiation noise from the outside to the integrated circuit on the upper surface side of the semiconductor substrate.

(First embodiment)
FIG. 1 is a sectional view of a semiconductor device as a first embodiment of the present invention. This semiconductor device is generally called a CSP and includes a silicon substrate (semiconductor substrate) 1. An integrated circuit (not shown) having a predetermined function is provided on the upper surface of the silicon substrate 1, and a plurality of connection pads 2 made of aluminum-based metal or the like are provided on the periphery of the upper surface so as to be connected to the integrated circuit.

  An insulating film 3 made of silicon oxide or the like is provided on the upper surface of the silicon substrate 1 excluding the central portion of the connection pad 2, and the central portion of the connection pad 2 is exposed through an opening 4 provided in the insulating film 3. Yes. A protective film 5 made of a thermosetting resin such as polyimide resin or epoxy resin is provided on the upper surface of the insulating film 3. An opening 6 is provided in the protective film 5 at a portion corresponding to the opening 4 of the insulating film 3.

  A base metal layer 7 made of a metal containing copper is provided on the upper surface of the protective film 5. A wiring 8 made of copper is provided on the entire upper surface of the base metal layer 7. One end of the wiring 8 including the base metal layer 7 is connected to the connection pad 2 through the openings 4 and 6 of the insulating film 3 and the protective film 5. A columnar electrode (projection electrode) 9 made of copper is provided on the upper surface of the connection pad portion of the wiring 8.

  A sealing film 10 is provided on the upper surface of the protective film 5 including the wiring 8 so that the upper surface thereof is flush with the upper surface of the columnar electrode 9. In this case, the sealing film 10 is made of a material in which a ferromagnetic powder 10b made of Fe, Co, Ni, FeNi or the like is mixed in a thermosetting resin 10a made of polyimide resin, epoxy resin or the like. . A solder ball 11 is provided on the upper surface of the columnar electrode 9.

  As described above, in this semiconductor device, the sealing film 10 is mixed with the ferromagnetic powder 10b made of Fe, Co, Ni, FeNi or the like in the thermosetting resin 10a made of polyimide resin, epoxy resin or the like. Therefore, the ferromagnetic powder 10b in the sealing film 10 is formed from the upper surface side (integrated circuit) of the silicon substrate 1 to the outside or vice versa. Unnecessary electromagnetic radiation noise to the integrated circuit) can be suppressed.

  Next, an example of a method for manufacturing this semiconductor device will be described. First, as shown in FIG. 2, on the upper surface of a silicon substrate in a wafer state (hereinafter referred to as a semiconductor wafer 21), a connection pad 2 made of aluminum metal, an insulating film 3 made of silicon oxide or the like, a polyimide resin, an epoxy resin, etc. A protective film 5 made of resin or the like is formed, and the connection pad 2 is exposed through the openings 4 and 6 formed in the insulating film 3 and the protective film 5.

  In this case, an integrated circuit (not shown) having a predetermined function is formed in a region where each semiconductor device is formed on the upper surface of the semiconductor wafer 21, and the connection pad 2 is electrically connected to the integrated circuit formed in the corresponding region. Connected. In FIG. 2, an area indicated by reference numeral 22 is an area corresponding to a dicing line.

  Next, as shown in FIG. 3, a base metal layer 7 is formed on the entire upper surface of the protective film 5 including the upper surfaces of the connection pads 2 exposed through the openings 4 and 6 of the insulating film 3 and the protective film 5. . In this case, the base metal layer 7 may be only a copper layer formed by electroless plating, or may be only a copper layer formed by sputtering, and a thin film such as titanium formed by sputtering. A copper layer may be formed on the layer by sputtering.

  Next, a plating resist film 23 is pattern-formed on the upper surface of the base metal layer 7. In this case, an opening 24 is formed in the plating resist film 23 in a portion corresponding to the wiring 8 formation region. Next, by performing electrolytic plating of copper using the base metal layer 7 as a plating current path, the wiring 8 is formed on the upper surface of the base metal layer 7 in the opening 24 of the plating resist film 23. Next, the plating resist film 23 is peeled off.

  Next, as shown in FIG. 4, a plating resist film 25 is formed on the upper surface of the base metal layer 7 including the wiring 8. In this case, an opening 26 is formed in the resist film 25 in the connection pad portion of the wiring 8, that is, the portion corresponding to the columnar electrode 9 formation region. Next, the columnar electrode 9 is formed on the upper surface of the connection pad portion of the wiring 8 in the opening 26 of the plating resist film 25 by performing electrolytic plating of copper using the base metal layer 7 as a plating current path. Next, when the plating resist film 25 is peeled off, and then unnecessary portions of the base metal layer 7 are removed by etching using the wiring 8 as a mask, the base metal layer 7 is formed only under the wiring 8 as shown in FIG. Remain.

  Next, as shown in FIG. 6, a thermosetting resin 10a made of a polyimide resin, an epoxy resin, or the like is formed on the upper surface of the protective film 5 including the wiring 8 and the columnar electrode 9 by a screen printing method, a spin coating method, or the like. A sealing film 10 made of a material in which a ferromagnetic powder 10b made of Fe, Co, Ni, FeNi or the like is mixed is formed so that its thickness is slightly larger than the height of the columnar electrode 9. Therefore, in this state, the upper surface of the columnar electrode 9 is covered with the sealing film 10. In this case, since the material in which the ferromagnetic powder 10b is mixed in the thermosetting resin 10a may be applied by a screen printing method, a spin coating method, or the like, the number of manufacturing steps can be prevented from increasing.

  Next, by appropriately polishing and removing the upper surface side of the sealing film 10, the upper surface of the columnar electrode 9 is exposed and the sealing including the exposed upper surface of the columnar electrode 9 is performed as shown in FIG. The upper surface of the stop film 10 is flattened. Next, as shown in FIG. 8, solder balls 11 are formed on the upper surface of the columnar electrode 9. Next, as shown in FIG. 9, when the sealing film 10, the protective film 5, the insulating film 3, and the semiconductor wafer 21 are diced along the dicing line 22, a plurality of semiconductor devices shown in FIG. 1 are obtained.

(Second Embodiment)
FIG. 10 is a sectional view of a semiconductor device as a second embodiment of the present invention. This semiconductor device is different from the semiconductor device shown in FIG. 1 in that the protective film (insulating film) 5 is mixed with a ferromagnetic powder 5b in a thermosetting resin 5a made of polyimide resin, epoxy resin, or the like. It is a point formed by the material.

  In this semiconductor device, the ferromagnetic powders 10b and 5b in the sealing film 10 and the protective film 5 are connected to the outside from the upper surface side (integrated circuit) of the silicon substrate 1 as compared with the case of the semiconductor device shown in FIG. On the contrary, unnecessary electromagnetic radiation noise from the outside to the upper surface side (integrated circuit) of the silicon substrate 1 can be further suppressed. Further, when the protective film 5 is formed, a material in which the ferromagnetic powder 5b is mixed in the thermosetting resin 5a may be applied by a screen printing method, a spin coating method, or the like, so that the number of manufacturing steps does not increase. Can be.

1 is a cross-sectional view of a semiconductor device as a first embodiment of the present invention. Sectional drawing of what was initially prepared in the case of manufacture of the semiconductor device shown in FIG. Sectional drawing of the process following FIG. Sectional drawing of the process following FIG. Sectional drawing of the process following FIG. Sectional drawing of the process following FIG. Sectional drawing of the process following FIG. Sectional drawing of the process following FIG. FIG. 9 is a cross-sectional view of the process following FIG. 8. Sectional drawing of the semiconductor device as 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Silicon substrate 2 Connection pad 3 Insulating film 5 Protective film 5a Thermosetting resin 5b Ferromagnetic powder 7 Base metal layer 8 Wiring 9 Columnar electrode 10 Sealing film 10a Thermosetting resin 10b Ferromagnetic powder 11 Solder ball 21 Semiconductor Wafer

Claims (8)

  A semiconductor substrate; an integrated circuit provided on the semiconductor substrate; a plurality of wirings provided to be electrically connected to the integrated circuit via connection pads; and a connection pad portion provided on the wirings. A protruding electrode; and a sealing film that covers the upper surface of the integrated circuit and that is provided around the protruding electrode and is made of a material in which ferromagnetic powder is mixed in a resin. Semiconductor device.   The invention according to claim 1, wherein the wiring is provided on an insulating film provided on the semiconductor substrate, and the insulating film is made of a material in which ferromagnetic powder is mixed in a resin. Semiconductor device.   3. The semiconductor device according to claim 1, wherein the ferromagnetic powder is made of any one of Fe, Co, Ni, and FeNi.   2. The semiconductor device according to claim 1, wherein a solder ball is provided on the protruding electrode. Forming a plurality of wirings electrically connected to the integrated circuit via connection pads on a semiconductor wafer having a plurality of integrated circuits formed on a main surface;
Forming a protruding electrode on the connection pad portion of the wiring;
Forming a sealing film made of a material in which ferromagnetic powder is mixed in a resin on the upper surface of the integrated circuit and around the protruding electrodes;
Dicing the semiconductor wafer and the sealing film to obtain a plurality of semiconductor devices;
A method for manufacturing a semiconductor device, comprising:   6. The semiconductor device according to claim 5, wherein the wiring is formed on an insulating film formed on the semiconductor substrate and made of a material in which ferromagnetic powder is mixed in a resin. Production method.   7. The method of manufacturing a semiconductor device according to claim 5, wherein the ferromagnetic powder is made of any one of Fe, Co, Ni, and FeNi.   6. The method of manufacturing a semiconductor device according to claim 5, further comprising a step of forming a solder ball on the protruding electrode after forming the sealing film.

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