JP2007019333A - Semiconductor device and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device having an inductor having an excellent characteristic by increasing the inductance of the inductor in a semiconductor device provided with an inductor.
A semiconductor device according to the present invention includes a substrate provided with an electrode on at least one surface, an insulating resin layer covering one surface of the substrate, a first magnetic layer disposed on the insulating resin layer, An inductor disposed on the first magnetic layer and electrically connected to the electrode, and a second magnetic layer disposed to cover the inductor, the first magnetic layer and the second magnetic layer The closed magnetic circuit is formed in a plane perpendicular to the direction of the current flowing in the inductor.
[Selection] Figure 1

Description

  The present invention relates to a semiconductor device including an inductor on a semiconductor substrate such as a silicon wafer or a resin substrate such as polyimide and a method for manufacturing the same.

In recent years, inductive elements such as inductors tend to be integrated on a semiconductor substrate in order to reduce costs and chip components.
When forming a spiral inductor on the surface of a silicon substrate, some of the electromagnetic energy created by the inductor is lost in the wiring that forms the silicon substrate and inductor due to the parasitic capacitance between the wiring and the underlying substrate (e.g., (See Patent Document 1 and Patent Document 2)
In the above document, one of the causes for the loss of electromagnetic energy is the short distance between the substrate and the spiral inductor. Therefore, by using a wafer level CSP (chip scale package) copper plating rewiring process and using a thick film resin as an insulating layer, the distance between the inductor and the substrate is increased, and the wiring resistance is reduced. An inductor that realizes a Q value has been developed (see, for example, Non-Patent Document 1).

FIG. 9 is a drawing showing an example of a conventional semiconductor device having a spiral inductor. FIG. 9A is a partially cutaway perspective view, and FIG. 9B is a cross-sectional view.
In this semiconductor device 40, an electrode 2 of an integrated circuit (IC) and a passivation film 3 (insulating layer) are formed on one surface of the semiconductor substrate 1 on which the integrated circuit 4 is formed. Further, a first insulating resin layer 41 is provided on the passivation film 3 of the semiconductor substrate 1, and a lower wiring layer electrically connected to the electrode 2 is provided on the first insulating resin layer 41. 42 is formed. Further, a second insulating resin layer 43 is formed so as to cover the semiconductor substrate 1 and the lower wiring layer 42, and an upper wiring having a spiral inductor 45 as an inductive element is formed on the second insulating resin layer 43. A layer 44 is provided. The spiral inductor 45 is electrically connected to the electrode 2 of the integrated circuit 4 through the lower wiring layer 42.

However, in such a semiconductor device, although the inductor is separated from the semiconductor substrate by the insulating resin layer, there is still a magnetic flux passing through the semiconductor substrate, and the device cannot be installed directly under the inductor. Sometimes.
In order to solve the above problem, meander type inductors are also used. However, the inductance value is small and a desired value may not be satisfied. Further, when trying to obtain a large inductance value, the size of the inductor becomes large.
For example, as described in JP-A-2002-45320, a proposal has been made to apply a ferromagnetic material to a spiral inductor, but the effect is weak because the volume of the ferromagnetic material is small and a closed magnetic circuit cannot be formed. . Further, since the ferromagnetic material is used, the IC process may be contaminated.

Further, the conventional on-chip inductor as described above can obtain only a low inductance value because of its small size.
Formula (1) shows a calculation formula of a typical solenoid model used when calculating the inductance value of the inductor.

Where k: Nagaoka coefficient, μ ₀ : vacuum permeability, μ _r : shaft permeability, A: coil cross-sectional area, n: number of turns per unit length of coil, l: coil axial direction Length.
In order to increase the inductance value, (a) the cross-sectional area of the coil is increased, (b) the number of turns of the coil is increased, (c) the length in the coil axial direction is increased. The chip size is small, the element shape that can be fabricated with WL-CSP technology is almost two-dimensional, and it is difficult to increase the cross-sectional area and the length at the same time. Therefore, there is a limit to increasing the inductance value with the on-chip inductor, and the value is about several nH to several tens nH. Therefore, there is a problem that an on-chip inductor cannot be used in applications that require a large inductance value, such as a DC-DC converter.

In recent years, a magnetic element using a magnetic material having a large μr has been developed in order to increase the inductance value without increasing the size of the inductor (for example, Patent Document 3). These magnetic elements have a structure in which a planar inductor is sandwiched between magnetic layers, and an insulating layer is formed between the magnetic layer and a wiring conductor forming a coil to reduce loss due to current leakage.
However, in this structure, as shown in FIG. 10, magnetic fields generated between adjacent wirings are generated in directions that cancel each other, resulting in a decrease in inductance value. In addition, compared with a conventional on-chip inductor, it is necessary to form a magnetic layer and an insulating layer on the upper and lower sides, respectively, which causes problems such as an increase in process, an increase in cost, and a decrease in yield. In addition, in this structure, magnetism leaks from the gap between the upper and lower magnetic films, and as a result, a significant increase in inductance cannot be expected.
JP 2002-24657 A JP 2003-86690 A JP-A-9-55316 Nikkei Microdevices March 2002, pages 125-127

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a semiconductor device including an inductor having an excellent characteristic by increasing the inductance of the inductor in a semiconductor device including the inductor. Another object of the present invention is to provide a method for manufacturing a semiconductor device having an inductor with high inductance and excellent characteristics.

According to a first aspect of the present invention, there is provided a semiconductor device comprising: a substrate provided with an electrode on at least one surface; an insulating resin layer covering one surface of the substrate; and a first magnetic layer disposed on the insulating resin layer. A semiconductor device comprising: an inductor disposed on the first magnetic layer and electrically connected to the electrode; and a second magnetic layer disposed to cover the inductor. One magnetic layer and the second magnetic layer are in contact with each other, and a closed magnetic circuit is formed in a plane perpendicular to the direction of current flowing in the inductor.
According to a second aspect of the present invention, in the semiconductor device according to the first aspect, the inductor has a meander shape or a spiral shape.
A semiconductor device according to a third aspect of the present invention is characterized in that, in the first or second aspect, a gap between wirings constituting the inductor is filled with an insulating resin.
According to a fourth aspect of the present invention, there is provided a method for manufacturing a semiconductor device, comprising: a substrate provided with an electrode on at least one surface; an insulating resin layer covering the one surface of the substrate; and a first disposed on the insulating resin layer. A magnetic layer; an inductor disposed on the first magnetic layer and electrically connected to the electrode; and a second magnetic layer disposed so as to cover the inductor; A method of manufacturing a semiconductor device in which a closed magnetic circuit is formed in a plane perpendicular to the direction of a current flowing in the inductor, wherein the first magnetic layer and the second magnetic layer are in contact with each other Forming a second magnetic layer on the layer in contact with the first magnetic layer so that a closed magnetic circuit is formed in a plane perpendicular to the direction of the current flowing in the inductor; To do.
According to a fifth aspect of the present invention, there is provided a semiconductor device having a substrate provided with an electrode on at least one surface, a magnetic layer covering one surface of the substrate, and disposed on the magnetic layer and electrically connected to the electrode. The magnetic layer has a sheet resistance of 1000 [Ω / sq] (thickness 1000 [Å]) or more.
A semiconductor device according to a sixth aspect of the present invention is the semiconductor device according to the fifth aspect, further comprising a second magnetic layer disposed so as to cover the inductor, wherein the first magnetic layer and the second magnetic layer are in contact with each other. The closed magnetic circuit is formed in a plane perpendicular to the direction of the current flowing in the inductor.
According to a seventh aspect of the present invention, in the semiconductor device according to the fifth or sixth aspect, the inductor has a meander shape or a spiral shape.
According to an eighth aspect of the present invention, there is provided a method for manufacturing a semiconductor device, comprising: a substrate provided with an electrode on at least one surface; a magnetic layer covering one surface of the substrate; and the magnetic layer disposed on the magnetic layer. And the magnetic layer has a sheet resistance of 1000 [Ω / sq] (thickness 1000 [Å]) or more, wherein the magnetic layer is formed on one surface of the substrate. And a step of forming a magnetic layer having a sheet resistance of 1000 [Ω / sq] (thickness 1000 [Å]) or more and a step of directly forming an inductor on the magnetic layer. .

In the present invention, by covering the inductor with the magnetic layer, a closed magnetic circuit can be formed in a plane perpendicular to the direction of the current flowing in the inductor, and the semiconductor substrate and the magnetic flux are not generated in the vertical direction. It can be a structure. As a result, the inductance value can be increased or the inductor can be downsized.
Further, in the present invention, it is possible to directly laminate the inductor and the magnetic layer without using an insulating layer between the inductor and the magnetic layer by using a material having a high resistance value for the magnetic layer. The process can be simplified.

  Hereinafter, an embodiment of a semiconductor device according to the present invention will be described with reference to the drawings.

<First embodiment>
FIG. 1 is a cross-sectional view showing an example of a semiconductor device of the present invention.
In this semiconductor device 10, an electrode 2 and a passivation film 3 of an integrated circuit (IC, not shown) are formed on the surface of a semiconductor substrate 1 on which an integrated circuit (not shown) is formed.
Further, the semiconductor device 10 includes an insulating resin layer 11 provided on the passivation film 3 of the semiconductor substrate 1, a first magnetic layer 12 provided on the insulating resin layer 11, and a first magnetic layer 12. It has a wiring layer 13 provided on top and a second magnetic layer 14 provided so as to cover the wiring layer 13. The wiring layer 13 has a meander-shaped inductor 13a as shown in FIG. 2 as an inductive element.

The semiconductor substrate 1 is provided with, for example, an Al pad as an electrode 2 on at least one surface of a base material 1a whose surface layer forms an insulating portion (not shown), and further a passivation film 3 (passivation) such as SiN or SiO ₂ on the surface. Insulating layer) is formed. The passivation film 3 is provided with an opening 5 at a position aligned with the electrode 2, and the electrode 2 is exposed through the opening 5. The passivation film 3 can be formed by, for example, the LP-CVD method, and the film thickness is, for example, 0.1 to 0.5 [μm].
Here, the electrode 2 for electrically connecting the wiring layer 13 having the meander-shaped inductor 13a to the integrated circuit is provided at two locations on the surface of the semiconductor substrate 1 (only one location is shown in the figure). .

In the present invention, since the meander-shaped inductor 13a is covered with the first magnetic layer 12 and the second magnetic layer 14, a closed magnetic circuit is formed in a plane perpendicular to the direction of the current flowing in the inductor. In addition, the semiconductor substrate 1 and the magnetic flux are not generated in the vertical direction. As a result, the inductance value can be increased or the inductor can be downsized.
In general, a magnetic material has a larger magnetic permeability than a nonmagnetic material, and the inductance of an inductor covered with a magnetic layer is proportional to the magnetic permeability. For this reason, a large inductance can be obtained by covering the inductor with a magnetic layer.
It is possible to increase the inductance of the inductor in proportion to the magnetic permeability of the magnetic layer. Therefore, the inductance can be increased by using a magnetic member having a relative permeability of several hundreds (for example, the permeability of ferrite is several hundreds).
Furthermore, by using a magnetic layer material having a high electrical resistivity such as ferrite, it is possible to directly contact the wiring layer and the magnetic layer, thereby reducing the number of processes. In addition, eddy current loss in the magnetic film is reduced.

  The semiconductor substrate 1 may be a semiconductor wafer such as a silicon wafer, or may be a semiconductor chip obtained by cutting (dicing) the semiconductor wafer into chip dimensions. When the semiconductor substrate 1 is a semiconductor chip, first, a plurality of semiconductor elements, ICs, induction elements, etc. are formed on a semiconductor wafer and then cut into chip dimensions to obtain a plurality of semiconductor chips. Can do.

The insulating resin layer 11 has an opening 15 formed at a position aligned with each electrode 2. The insulating resin layer 11 is made of, for example, a polyimide resin, an epoxy resin, a silicone resin, or the like, and has a thickness of, for example, 1 to 30 μm.
The insulating resin layer 11 can be formed by, for example, a spin coating method, a printing method, a laminating method, or the like. The opening 15 can be formed by patterning using a photolithography technique, for example.

The first magnetic layer 12 has an opening 16 formed at a position aligned with each electrode 3. Further, the first magnetic layer 12 may be larger than the inductor size by at least 50 μm in order to form a closed magnetic circuit.
As the magnetic layer material, for example, various magnetic members such as ferrite mainly composed of Ni, Fe, Zn, amorphous metal such as CoNbZr, and ferromagnetic metal such as Ni-Fe can be used. For example, 1 to 10 [μm]. The first magnetic layer can be formed by, for example, a plating method, a sputtering method, a spin coating method, a screen printing method, or the like.
The magnetic layer material preferably has a high electrical resistance. However, when a low-resistance magnetic layer material is used, the same effect can be obtained by disposing an insulating layer between the first magnetic layer 12 and the wiring layer 13. It is possible to obtain.

The wiring layer 13 has a meander inductor 13a as an inductive element.
As a material of the wiring layer 13, for example, Cu or the like is used, and its thickness is, for example, 1 to 20 μm. Thereby, sufficient electrical conductivity is obtained. The wiring layer 13 can be formed by, for example, a plating method such as an electrolytic copper plating method, a sputtering method, a vapor deposition method, or a combination of two or more methods.

The second magnetic layer 14 forms a pattern in contact with the first magnetic layer 12 in order to form a closed magnetic circuit.
The second magnetic layer 14 can be formed of the above-described magnetic layer material by, for example, a plating method or a sputtering method. The thickness is, for example, 1 to 10 [μm].
The magnetic layer material preferably has a high electrical resistance. However, when a low resistance magnetic layer material is used, the same effect can be obtained by arranging an insulating layer between the wiring layer 13 and the second magnetic layer 14. It is possible to obtain.

  In FIG. 1, only a portion corresponding to one inductive element on the semiconductor substrate is illustrated, but the present invention can also be applied to a semiconductor device including a plurality of inductive elements. Although not shown, in the semiconductor device of the present invention, a sealing resin layer is formed on the second magnetic layer as necessary, and structures such as output terminals to the outside such as bumps are further provided. Can be added.

Next, a method for manufacturing the semiconductor device shown in FIG. 1 will be described.
First, as shown in FIG. 3A, a semiconductor substrate 1 having an integrated circuit (not shown), an electrode 2 and a passivation film 3 is prepared. As described above, the semiconductor substrate 1 has the electrode 2 and the passivation film 3 formed on one surface of the base material 1 a, and the passivation film 3 is provided with the opening 5 at a position aligned with the electrode 2. It is a semiconductor wafer. The passivation film 3 is formed by, for example, LP-CVD, and the film thickness is, for example, 0.1 to 0.5 [μm].

Next, as shown in FIG. 3B, an insulating resin layer 11 having an opening 15 is formed on the passivation film 3 of the semiconductor substrate 1.
Such an insulating resin layer 11 is formed by, for example, forming a film made of the above resin on the entire surface of the passivation film 3 by, for example, a spin coating method, a printing method, or a laminating method, and then performing patterning using, for example, a photolithography technique. It can be formed by forming the opening 15 at a position aligned with the electrode 2.

Next, as shown in FIG. 3C, the first magnetic layer 12 is formed on the semiconductor substrate 1. The thickness is, for example, 1 to 10 [μm]. At this time, in order to form a closed magnetic circuit, the first magnetic layer 12 may be larger than the inductor size by at least 50 [μm].
The first magnetic layer 12 can be formed, for example, by depositing the above-described magnetic material by a plating method or a sputtering method. At this time, the Al pad and the scribe line of the chip are exposed. Furthermore, the opening 15 is formed by, for example, ion milling, etching by ICP-RIE, or patterning by a photolithography method or a lift-off method.

  Next, as shown in FIG. 3D, the wiring layer 13 is formed on the first magnetic layer 12. The thickness is, for example, 0.1 to 30 [μm]. A method for forming the wiring layer 13 in a predetermined region is not particularly limited.

Here, an example of a suitable method for forming the wiring layer 13 will be described.
First, a thin seed layer (not shown) for electrolytic plating is formed on the entire surface of the first magnetic layer or a necessary region by sputtering or the like. The seed layer is, for example, a laminated body made of a Cu layer and a Cr layer formed by a sputtering method, or a laminated body made of a Cu layer and a Ti layer. Further, it may be an electroless Cu plating layer, a metal thin film layer formed by a vapor deposition method, a coating method, a chemical vapor deposition method (CVD), or the like, or a combination of the above metal layer forming methods. Good.

Next, a resist film (not shown) for electrolytic plating is formed on the seed layer. The resist film is provided with an opening in a region where the wiring layer 13 is to be formed, and the seed layer is exposed in the opening. The resist film can be formed by, for example, a method of laminating a film resist, a method of spin-coating a liquid resist, or the like and then patterning by a photolithography technique.
Then, a wiring layer 13 made of Cu or the like is formed on the exposed seed layer using the resist film as a mask by electrolytic plating or the like. Thus, after the wiring layer 13 is formed in a desired region, unnecessary resist film and seed layer are removed by etching, and the first magnetic layer 12 is exposed in a portion other than the region where the wiring layer 13 is formed. (See FIG. 3D).

At this time, when a magnetic layer material having a low electric resistance is used for the first magnetic layer 12, an insulating layer is provided between the first magnetic layer 12 and the wiring layer 13. The insulating layer can be formed, for example, by depositing SiO ₂ or SiN or applying an insulating resin.
That is, by using a magnetic layer material having high electrical resistivity such as ferrite, the first magnetic layer 12 and the wiring layer 13 can be directly laminated, and the number of processes can be reduced. However, when an alloy is formed between the first magnetic layer 12 and the wiring layer 13, the above insulating layer is required as a barrier layer.

Next, as shown in FIG. 3E, the second magnetic layer 14 is formed. The thickness is, for example, 1 to 10 [μm]. At this time, in order to form a closed magnetic path, a pattern is formed so as to be in contact with the first magnetic layer 12. By connecting the first magnetic layer 12 and the second magnetic layer 14 in this step, a closed magnetic circuit connected so as to cover the inductor 13a is formed, so that leakage of the magnetic field to the outside can be suppressed.
The second magnetic layer 14 can be formed by depositing the above-described magnetic material by, for example, a plating method, a sputtering method, a spin coating method, a screen printing method, or the like. Further, for example, patterning is performed in a predetermined shape by patterning using a photolithography method or a lift-off method.
At this time, when a magnetic layer material having a low electric resistance is used for the second magnetic layer 14, an insulating layer is formed between the wiring layer 13 and the second magnetic layer 14. The insulating layer can be formed, for example, by depositing SiO ₂ or SiN or applying an insulating resin.
After the second magnetic layer 14 is formed, a semiconductor chip on which the inductive element is packaged can be obtained by dicing a semiconductor wafer on which various structures such as the inductive element are formed into predetermined dimensions.

In the semiconductor device 10, since the inductor 13a is covered with the first magnetic layer 12 and the second magnetic layer 14, a closed magnetic circuit can be formed in a plane perpendicular to the direction of the current flowing in the inductor. And a structure in which no magnetic flux is generated in the vertical direction with respect to the substrate. Moreover, since the magnetic flux density is efficiently increased by arranging the magnetic layer in the vicinity of the inductor, the inductance value can be increased or the inductor can be downsized.
Further, in the semiconductor device 10, since the wiring layer 12 is formed via the insulating resin layer 11, the distance from the substrate is increased and the characteristics are improved. In addition, contamination of the semiconductor substrate can be reduced. Further, by insulating with the thick insulating resin layer 11, the problem of contamination can be avoided.

  In the semiconductor device 10, as shown in FIG. 4, the insulating resin 19 may be filled in the gaps between the wires constituting the inductor 13 a. By filling the gap between the wires constituting the inductor 13a with the insulating resin 19, the second magnetic layer 14 does not go around the side surfaces of the wires constituting the inductor 13a. This makes it possible to further improve the performance of the inductor.

<Second Embodiment>
FIG. 5 is a cross-sectional view showing an example of the semiconductor device of the present invention.
In FIG. 5, the same components as those in FIG.
The semiconductor device 20 covers the first magnetic layer 22 provided on the passivation film 3 of the semiconductor substrate 1, the wiring layer 23 provided on the first magnetic layer 22, and the wiring layer 23. And a second magnetic layer 24 provided. The wiring layer 23 has a meander-shaped inductor 22a as an inductive element.

In the present invention, a material having a sufficiently high resistance value is used as the magnetic layer material. Here, the resistance value is sufficiently high means that the resistance value is high enough to insulate the wiring forming the inductor without interposing an insulating layer between the wiring layer and the magnetic layer. .
By using a material having a sufficiently high resistance value as the magnetic layer material, it is possible to insulate the wiring forming the inductor without interposing an insulating layer therebetween. As a result, the inductor and the magnetic layer can be directly laminated without interposing an insulating layer between the inductor and the magnetic layer, so that the process can be simplified. In addition, the manufacturing cost can be reduced by simplifying the process. In addition, the yield can be improved by simplifying the process.

Specifically, the magnetic layer material preferably has a sheet resistance of 1000 [Ω / sq] (thickness 1000 [Å]) or more. This makes it possible to sufficiently insulate the wiring forming the inductor without providing an insulating layer.
Examples of such a magnetic layer material include Ni—Zn ferrite. As a result, the wiring forming the inductor can be sufficiently insulated, and efficient magnetic induction can be realized to improve the characteristics of the inductor.
The thickness of such a magnetic layer is preferably 0.5 to 20 [μm], for example. Thereby, it is possible to sufficiently insulate the wiring forming the inductor.

Next, a method for manufacturing the semiconductor device shown in FIG. 5 will be described.
First, as shown in FIG. 6A, a semiconductor substrate 1 having an integrated circuit (not shown), an electrode 2 and a passivation film 3 is prepared.
Next, as shown in FIG. 6B, a first magnetic layer 22 is formed on the passivation film 3. The thickness is, for example, 1 to 10 [μm]. At this time, in order to form a closed magnetic circuit, the first magnetic layer 21 may be larger than the inductor size by at least 50 [μm].

Next, as shown in FIG. 6C, the wiring layer 23 is formed directly on the first magnetic layer 22. The thickness is, for example, 0.1 to 30 [μm].
Next, as shown in FIG. 6D, the second magnetic layer 24 is directly formed so as to cover the wiring layer 23. The thickness is, for example, 1 to 10 [μm]. At this time, a pattern is formed so as to be in contact with the first magnetic layer 22 in order to form a closed magnetic path. By connecting the first magnetic layer 22 and the second magnetic layer 24 by this step, a closed magnetic circuit connected so as to cover the inductor 23 is formed, so that leakage of the magnetic field to the outside can be suppressed.

In the semiconductor device 20, the magnetic layer material is made of a material having a sheet resistance of 1000 [Ω / sq] (thickness 1000 [Å]) or more and a sufficiently high resistance value for insulation. Since the magnetic layer and the wiring layer can be directly laminated without intervention, the process can be simplified. As a result, manufacturing cost can be reduced and yield can be improved.
Further, in the semiconductor device 20, since the inductor 23 is covered with the first magnetic layer 21 and the second magnetic layer 24, a closed magnetic circuit is formed in a plane perpendicular to the direction of the current flowing in the inductor. And a structure in which the magnetic flux is not generated in the vertical direction with respect to the substrate. Moreover, since the magnetic flux density is efficiently increased by arranging the magnetic layer in the vicinity of the inductor 23, the inductance value can be increased or the inductor can be downsized.
When the magnetic layer is formed on the wiring constituting the inductor, the wiring can be individually covered with the magnetic layer, so that loss due to cancellation of the magnetic field between the wirings can be eliminated.

Although the semiconductor device of the present invention has been described above, the present invention is not limited to this, and can be appropriately changed without departing from the spirit of the invention.
In the above-described embodiment, the meander-shaped inductor has been described as an example of the inductor. However, the present invention is not limited to this, and a spiral shape or other shapes as shown in FIG. The present invention can also be applied to other inductors.

A sealing resin layer (not shown) may be provided on the second magnetic layer. The sealing resin layer is made of, for example, polyimide resin, epoxy resin, silicone resin, or the like, and the thickness thereof is, for example, 1 to 30 [μm]. The sealing resin layer is provided with an opening for outputting a terminal to the outside.
Furthermore, structures such as output terminals to the outside such as bumps can be added on the sealing resin layer as necessary.
In the semiconductor device of the present invention, a wiring layer, a magnetic layer, or the like may be further stacked on the above structure. By using a multilayer structure, the inductance value can be further increased.
The effect of the present invention is not limited to the case where an inductor is formed on a semiconductor substrate on which an integrated circuit is formed, but also when the inductor is formed on an FPC, a glass substrate, a ceramic substrate, or the like. .

Example 1
As shown in FIG. 1, a semiconductor substrate 1, which is a silicon substrate, an insulating resin layer 11, a first magnetic layer 12, a wiring layer 13 having a meander inductor 13a as an inductive element, a second magnetic layer 14, A semiconductor device 10 having the above was manufactured.
The insulating resin layer was formed by forming a polyimide insulating resin to a thickness of 10 [μm] by spin coating.
The first and second magnetic layers were formed by depositing Ni—Zn-based ferrite to a thickness of 10 μm by sputtering.
The wiring layer was formed by forming a film with a thickness of 10 [μm] by electrolytic copper plating.
The inductance value in the semiconductor device 10 was measured. The results (marked with ◇) are shown in FIG.

(Comparative Example 1)
A semiconductor device was fabricated in the same manner as in Example 1 except that no magnetic layer was provided, and the inductance value was measured. The result (□ mark) is shown in FIG.
From FIG. 7, when comparing the two, the inductor of Example 1 with a magnetic layer (marked with ◇) has an inductance value about nine times that of the inductor of Comparative Example 1 with no magnetic layer (marked with □). It turns out to rise.

(Example 2)
As shown in FIG. 5, a semiconductor device 20 having a semiconductor substrate 1 that is a silicon substrate, a first magnetic layer 21, a wiring layer 22 having a meander inductor as an inductive element, and a second magnetic layer 23 is manufactured. did.
The first and second magnetic layers were formed by depositing Ni—Zn ferrite to a thickness of 1 μm by sputtering. The magnetic layer had a magnetic permeability of μ = 300, and an electric conductivity of 2.0 × 10 ⁻³ [Ω ⁻¹ m ⁻¹ ].
The wiring layer was formed by forming a film with a thickness of 10 μm by electrolytic copper plating. The size of the on-chip inductor was 2 × 2 [mm ² ], L / S = 150/30 [μm], and the number of turns was 3.
The inductance value in the semiconductor device 20 was measured. The results (marked with ◇) are shown in FIG.

(Comparative Example 2)
Semiconductor device as in Example 2 except that the first insulating layer is disposed between the first magnetic layer and the wiring layer, and the second insulating layer is disposed between the wiring layer and the second magnetic layer. Was made.
The first and second insulating layers were formed by depositing a polyimide insulating resin by spin coating. The thickness of the first insulating layer was 10 [μm]. The thickness of the second insulating layer was 20 [μm] between the first insulating layer and the second magnetic layer in the space portion of the inductor, and 10 [μm] between the wiring in the inductor line portion and the second magnetic layer. .
The inductance value in this semiconductor device was measured. The result (□ mark) is shown in FIG.
FIG. 8 shows a comparison between the two inductors (marked with ◇) in which the insulating layer was not formed between the magnetic layer and the wiring layer. The insulating layer was formed between the magnetic layer and the wiring layer. It was found that the inductance value increased by about 6% as compared with the inductor of Comparative Example 2 (marked by □).

  The present invention can be applied to various semiconductor devices having an inductive element such as a non-contact IC tag semiconductor device in which the inductive element functions as an antenna coil.

It is a typical sectional view showing an example of a semiconductor device concerning the present invention. FIG. 2 is a schematic plan view showing the shape of an inductor provided in the semiconductor device of FIG. 1. FIG. 2 is a schematic cross-sectional view showing an example of a method for manufacturing the semiconductor device shown in FIG. 1 in the order of steps. It is typical sectional drawing which shows another example of the semiconductor device which concerns on this invention. It is typical sectional drawing which shows another example of the semiconductor device which concerns on this invention. FIG. 6 is a schematic cross-sectional view showing an example of a manufacturing method of the semiconductor device shown in FIG. 5 in order of steps. It is a graph which shows a test result. It is a graph which shows a test result. (A) It is a partial notch perspective view which shows an example of the conventional semiconductor device, (b) It is sectional drawing which shows the principal part of the conventional semiconductor device. It is a schematic diagram which shows the magnetic field produced between wiring in the conventional semiconductor device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Semiconductor substrate, 2 Electrode, 3 Passivation film | membrane, 5 Opening part, 10 Semiconductor device, 11 Insulating resin layer, 12 1st magnetic layer, 13 Wiring layer, 13a Inductor (inductive element), 14 2nd magnetic layer.

Claims (8)

A substrate provided with electrodes on at least one surface;
An insulating resin layer covering one surface of the substrate;
A first magnetic layer disposed on the insulating resin layer;
An inductor disposed on the first magnetic layer and electrically connected to the electrode;
A second magnetic layer disposed so as to cover the inductor,
The semiconductor device according to claim 1, wherein the first magnetic layer and the second magnetic layer are in contact with each other, and a closed magnetic circuit is formed in a plane perpendicular to a direction of current flowing in the inductor.   The semiconductor device according to claim 1, wherein the inductor has a meander shape or a spiral shape.   The semiconductor device according to claim 1, wherein a gap between wirings constituting the inductor is filled with an insulating resin. A substrate provided with an electrode on at least one surface, an insulating resin layer covering one surface of the substrate, a first magnetic layer disposed on the insulating resin layer, and disposed on the first magnetic layer; An inductor electrically connected to the electrode, and a second magnetic layer disposed so as to cover the inductor, wherein the first magnetic layer and the second magnetic layer are in contact with each other, A method of manufacturing a semiconductor device in which a closed magnetic circuit is formed in a plane perpendicular to the direction of current flowing in an inductor,
On the first magnetic layer, a second magnetic layer is formed in contact with the first magnetic layer so that a closed magnetic circuit is formed in a plane perpendicular to the direction of the current flowing in the inductor. A method of manufacturing a semiconductor device. A substrate provided with electrodes on at least one surface;
A magnetic layer covering one surface of the substrate;
A semiconductor device comprising an inductor disposed on the magnetic layer and electrically connected to the electrode,
The magnetic layer has a sheet resistance of 1000 [Ω / sq] (thickness 1000 [Å]) or more. A second magnetic layer disposed to cover the inductor;
The first magnetic layer and the second magnetic layer are in contact with each other, and a closed magnetic circuit is formed in a plane perpendicular to the direction of current flowing in the inductor. Semiconductor device.   The semiconductor device according to claim 5, wherein the inductor has a meander shape or a spiral shape. A substrate provided with an electrode on at least one surface; a magnetic layer covering the one surface of the substrate; and an inductor disposed on the magnetic layer and electrically connected to the electrode, the magnetic layer comprising: A method of manufacturing a semiconductor device having a sheet resistance of 1000 [Ω / sq] (thickness 1000 [Å]) or more,
Forming a magnetic layer having a sheet resistance of 1000 [Ω / sq] (thickness 1000 [Å]) or more on one surface of the substrate;
And a step of directly forming an inductor on the magnetic layer.

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