Magnetic thin film, magnetic component that uses this magnetic thin film, manufacturing methods for the same, and a power conversion device

Abstract

On top of a silicon substrate, a polyimide film with a thickness of 10 μm is formed. On top of this, a magnetic thin film that is a polyimide film containing Fe fine particles and that has a thickness of 20 μm is formed. On top of this magnetic thin film, a patterned Ti / Au film and a Ti / Au connection conductor are formed. On top of this, a polyimide film with a thickness of 10 μm, and a Cu coil with a height 35 μm, width 90 μm, space 25 μm, and a polyimide layer that fills the spaces in the Cu coil are formed. On top of this, via a polyimide film with a thickness of 10 μm, a magnetic thin film that is a polyimide film containing Fe particles and that has a thickness of 20 μm is formed. This thin film inductor has a small alternating current resistance. The present invention provides a magnetic thin film that is well suited for mass production, can be manufactured easily, can be made into a thick film, has soft magnetic qualities, and is inexpensive. The present invention also provides a magnetic component that uses this magnetic thin film, manufacturing methods for these, and a power conversion device.

Description

BACKGROUND OF THE INVENTION [0001] The present invention relates to a magnetic thin film that can act as a magnetic core for a magnetic component such as a reactor, transformer, and magnetic head and the like. The present invention also relates to a magnetic component in which this magnetic thin film is formed on top of a semiconductor substrate. The present invention also relates to their manufacturing methods. The present invention also relates to a power conversion device. [0002] In the prior art, the magnetic thin film that is the magnetic core of magnetic components such as reactors, transformers, and magnetic heads, and the like is generally manufactured by methods such as sintering, rolling, plating, and sputtering of magnetic materials. [0003] Depending on the usage of the magnetic component, different magnetic qualities are needed. As a general classification, there are hard magnetic qualities and soft magnetic qualities. In hard magnetic qualities, the B-H quality has an a...

AI Technical Summary

Benefits of technology

[0018] It is an object of the present invention is to provide a magnetic thin film that is well suited for mass production, can be manufactured easily, can be made into a thick film, has soft magnetic qualities, and is inexpensive. The present invention also provides a magnetic component that uses this magnetic thin film, manufacturing methods for these, and a power conversion device.

[0121] As described above, fine particles of magnetic material are dispersed in a medium of resin or a solvent. This medium is coated, dried, and sintered. With this simple method, a magnetic thin film that is suited for mass production, is easy to manufacture, can be made into a thick film, and has soft magnetic qualities can be manufactured inexpensively. Furthermore, magnetic components using this magnetic thin film and power conversion devices can also be manufactured inexpensively.

Problems solved by technology

As a result, it is difficult to form a magnetic thin film on top of a semiconductor substrate which has a built-in IC (integrated circuit) and the like.

Furthermore, when using plating, although manufacture by normal temperature treatment is possible, the control of the film thickness of the magnetic thin film is difficult.

As a result, it is difficult to obtain a good magnetic quality.

However, the manufacture process is complex, and mass production is difficult.

Therefore, the manufacture cost of magnetic components using this magnetic thin film is high.

Furthermore, because the speed of growth is slow with the sputter method, making a thick film is difficult.

Even if mass production is not considered, if the thickness is made any greater, there can be cracking and loss due to membrane stress.

However, with magnetic thin films formed in this manner, because a sputter method is used, the manufacturing costs are high, and making a thick film is difficult.

In responding to this demand, this bulky transformer of the prior art has been a large bottleneck.

The interlinkage flux between the primary and secondary coils is reduced, and as a result, the magnetic bond between them is weakened, and the output from the primary side is not efficiently transmitted to the secondary side.

As a result, with the construction of the prior art, in general, the transformer has a low conversion efficiency.

However, in recent years, in conjunction with the miniaturization and high density mounting of electrical components, there have been problems with electromagnetic interference.

Because the coated wires of the prior are only for electrical insulation, the mutual interference from the magnetic fields created by current flowing in the lead wires cannot be avoided.

However, the miniaturization of magnetic induction components such as coil and transformer and the like is difficult.

Because these take up a large volume, the miniaturization of the power source module is limited.

However, using thin film technology, the process for forming a planar magnetic induction component on top of a substrate with a built-in semiconductor integrated circuit is complex and lengthy.

Furthermore, when the planar magnetic induction component is formed by a thin film process, the magnetic thin film and the insulating filler material shrink due to heat treatment.

With this stress, there can be warping of the substrate, and processing becomes difficult.

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