JP2000101025A - Integrated circuit mounted with magnetic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the area of an integrated circuit as a whole by forming a magnetic device in flat shape and high in performance on a semiconductor integrated circuit by forming an insulating film on a protective film making its top surface flat. SOLUTION: A silicon nitride protective layer 3 is deposited on the top surface of a semiconductor integrated circuit 2. Then, an insulation film 4 of the thermosetting resin such as polyimide is formed on the rugged upper side of the protective layer 3. When an insulating film 4 is formed, first a thermosetting resin is deposited as high as a level 31. Then, a film-like core 53 of magnetic material is formed, and then thermosetting resin is laminated as high as a level 42 above the top surface of the first core 53 by a prescribed distance. Then, a vertical hole is bored in the insulating film 4 and the protective layer 3, so as to form an interlayer wiring 52 that connects a coil 51 and an electrode to a wiring 22. Then, the coil 51 and the interlayer wiring 52 are formed, and thermosetting resin is piled as high as a level 43 for the formation of the insulation film 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an integrated circuit having a magnetic element mounted on a semiconductor integrated circuit.

[0002]

2. Description of the Related Art For example, according to Japanese Patent Application Laid-Open No. Hei 5-101937, a protective film such as silicon nitride is formed on a semiconductor integrated circuit. It is known that a core is formed and a magnetic element formed by the coil portion and the core is formed on a semiconductor integrated circuit.

For example, Japanese Utility Model Laid-Open Publication No. 57-195852 discloses a magnetic element formed by arranging a magnetic element comprising a coil portion called a metal film piece and a film-shaped core called a magnetic film in a semiconductor integrated circuit. I have.

[0004]

SUMMARY OF THE INVENTION The above-mentioned Japanese Patent Laid-Open Publication No.
In an integrated circuit known from Japanese Patent No. 1937, a magnetic element is formed on a protective film formed on a semiconductor integrated circuit. A pattern is formed over several layers on the surface of the semiconductor integrated circuit. Generally, the surface of a semiconductor integrated circuit has irregularities because the transistor region is low and the wiring region is high. Even if a protective film is formed on the semiconductor integrated circuit, the thickness of the protective film cannot be so large for the sake of manufacturing. Therefore, the surface of the protective film is also uneven due to the unevenness of the surface of the semiconductor integrated circuit. Normally, since a magnetic element has a much larger area than a transistor, if the magnetic element is provided over an uneven area, the magnetic element cannot be formed into a flat shape and a high-performance magnetic element can be formed. It becomes difficult.

On the other hand, in the integrated circuit disclosed in Japanese Utility Model Laid-Open No. 57-195852, a magnetic element is formed side by side with a semiconductor integrated circuit. In this case, since the magnetic element and the semiconductor integrated circuit are not arranged so as to overlap each other, there is a limit in reducing the area of the entire integrated circuit. Further, since there is no protection mechanism between the magnetic element and the semiconductor integrated circuit, the material of the film-shaped core may contaminate the semiconductor substrate and adversely affect the performance of the semiconductor integrated circuit. Further, the magnetic flux leaked from the magnetic element may adversely affect the operation of the semiconductor integrated circuit.

In view of the above problems, an object of the present invention is to provide an integrated circuit in which a magnetic element is mounted above a semiconductor integrated circuit without the above problems.

[0007]

According to the present invention, there is provided an integrated circuit in which a magnetic element is mounted on a semiconductor integrated circuit covered with a protective film, the upper surface of which is flat on the protective film. Element having a coil portion parallel to a semiconductor integrated circuit and a film-shaped core located between the coil portion and the semiconductor integrated circuit on an upper surface of the insulating film. Is provided.

By providing an insulating film having a flat upper surface,
Since the magnetic element can be formed in a flat shape, a high-performance magnetic element can be formed above the semiconductor integrated circuit.
Further, since the semiconductor integrated circuit and the magnetic element are arranged so as to overlap with each other, the area of the entire integrated circuit is reduced. Further, since the protective film is interposed between the semiconductor integrated circuit and the core, the semiconductor integrated circuit is less likely to be contaminated with the core material. Further, since the film-shaped core is located between the coil part constituting the magnetic element and the semiconductor integrated circuit, the magnetic flux generated in the coil part is cut off by the core, and the magnetic flux hardly affects the semiconductor integrated circuit.

If the magnetic element has a second film-shaped core paired with the core with the coil interposed therebetween, the magnetic flux generated in the coil is interrupted by the upper and lower cores. The performance of the element is further improved, and the magnetic flux leakage from the magnetic element to the semiconductor integrated circuit is further reduced.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, reference numeral 1 denotes a part of a cross section of an example of an integrated circuit according to the present invention, which has a magnetic element section 5 above a normal semiconductor integrated circuit section 2. 21
Is a substrate of the semiconductor integrated circuit section 2 and is made of single crystal silicon. Transistors, resistors, capacitors, and the like are formed on the upper surface of the substrate 21 by MOS technology or bipolar technology.
Are formed. A protective film 3 made of silicon nitride is provided on the upper surface of the semiconductor integrated circuit 2.
In the present invention, an insulating film 4 made of a thermosetting resin such as polyimide is formed on the upper surface of the protective film 3. In this embodiment mode, the insulating film 4 is formed three times and overlapped. Insulating film 4
Is formed, a thermosetting resin is first applied to the level indicated by 41. Next, a film-like first material made of a nickel-iron alloy or a ferrite or an amorphous alloy which is a magnetic material is used.
The core 53 is formed. Next, the thermosetting resin is laminated to a level indicated by 42 which is a predetermined distance above the upper surface of the first core 53. Next, the insulating film 4 and the protective film 3 are formed so that an interlayer wiring 52 connecting the coil portion 51 to the electrode and the wiring 22 is formed.
A vertical hole will be established. Next, a coil portion 51 made of aluminum, copper, or gold and an interlayer wiring 52 are formed. The coil portion 51 is formed, for example, as shown in FIG. Thereafter, the thermosetting resin is overlaid to the level indicated by 43 to complete the insulating film 4. In the present embodiment, a film-like core 54 made of a nickel-iron alloy, ferrite, or an amorphous alloy is further formed on the upper surface of the insulating film 4.

[0011]

As is apparent from the above description, according to the present invention, an insulating film is formed on an uneven protective film so that the upper surface becomes flat, and a semiconductor integrated circuit is formed on the insulating film. Since a magnetic element composed of a parallel coil part and a film-shaped core located between the coil part and the semiconductor integrated circuit is formed, a high-performance magnetic element is formed above the semiconductor integrated circuit. Thus, the area of the entire integrated circuit is reduced, and leakage of magnetic flux from the magnetic element to the semiconductor integrated circuit can be eliminated.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a configuration of an embodiment of the present invention.

FIG. 2 is a plan view showing a pattern of a coil unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Integrated circuit mounting magnetic element 2 Semiconductor integrated circuit 3 Protective film 4 Insulating film 5 Magnetic element

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Takeshi Ozawa 2-1-2-5-26 Nakao, Asahi-ku, Yokohama-shi, Kanagawa Prefecture (72) Inventor Yasuhisa Baba 86-6-123 Higashikawashima-cho, Hodogaya-ku, Yokohama-shi, Kanagawa Prefecture F-term (Reference) 5E070 AB01 AB10 BA20 BB01 BB02 CB12 CB20 DA17 5F038 AZ04 AZ10 EZ20

Claims (2)

[Claims] In an integrated circuit having a magnetic element mounted on a semiconductor integrated circuit covered with a protective film, an insulating film is formed on the protective film so that an upper surface is flat, and an upper surface of the insulating film is An integrated circuit mounted with a magnetic element, comprising: a magnetic element including a coil portion parallel to the semiconductor integrated circuit and a film-shaped core located between the coil portion and the semiconductor integrated circuit. . 2. The integrated circuit according to claim 1, wherein the magnetic element has a second film-shaped core that forms a pair with the core with a coil portion interposed therebetween.