JPH0658846B2 - Thin film inductor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to improvements in high density thin film inductors operating at high frequencies.

<Prior Art> FIG. 3 shows a perspective view of a commonly used inductor, for example. In FIG. 3, 1 is a substrate, 6 is a strip-shaped magnetic body, and 7 is a conductor. Next, the operation will be described. The inductor is composed of a plurality of magnetic bodies 6 and a conductor 7 covered with an insulator surrounding the magnetic bodies 6. By making the magnetic body 6 serving as the magnetic core thin and close to each other, the leakage magnetic flux can be reduced and the demagnetizing field can be reduced, and a high inductor value can be obtained.

<Problems to be Solved by the Invention> However, in the conventional inductance, the gap between the strip-shaped magnetic bodies is large, and it is difficult to reduce the size of the inductor. Therefore, the present invention aims to increase the magnetic film per unit area (volume), increase the inductance value per unit area, and obtain a thin film inductor that operates in a high frequency region.

<Means for Solving the Problems> In the thin film inductor according to the present invention, a plurality of conductor films are arranged on an insulating plate, and first and second strip-shaped magnetic layers that are magnetic cores are formed through a thin insulating layer so as to be orthogonal to the conductor films. A plurality of body film rows are arranged in high density, and a conductor electrically connected to the lower conductor is arranged in the magnetic body film row via a thin film insulating layer.

<Operation> The thin-film inductor of the present invention is configured by arranging conductor films above and below a magnetic core. Since the magnetic core has strip-shaped magnetic material films arranged in close proximity to each other, a magnetic circuit with a small leakage flux is formed. A high inductance value can be obtained.

<Examples> Examples of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing an embodiment of a thin film inductor according to the present invention,
FIG. 2 is a sectional view taken along line ab of FIG. First
In FIG. 2 and FIG. 2, 11 is an insulating substrate, 12 is a plurality of strip-shaped conductor films, 13 is an insulating film, 14 is a plurality of first strip-shaped magnetic film rows orthogonal to the conductor film 12, and 15 is magnetic. It is a second strip-shaped magnetic material film array provided in parallel with the body film array 14. In FIG. 1, the conductor film 12 and the magnetic film array 1 are shown.
Although the insulating film between 4 and 15 is omitted, the conductor film 12 and the magnetic film arrays 14 and 15 are insulated by the insulating film 13 as shown in FIG. Although not shown in the figure, the conductor film 12 has good adhesion to the substrate 11 by applying a suitable base film to the insulating substrate 11. The first magnetic material film array 14 and the second magnetic material film array 15 are arranged in close proximity to each other with an insulating film 13 such as SiO ₂ . Next, the operation will be described. Conductor film 12
Current flows around the magnetic film rows 14 and 15 which are a plurality of magnetic cores, and causes magnetic flux to be generated therein. All the magnetic fluxes in the respective magnetic cores flow in the same direction, and since they are in the form of thin strips that are close to each other, the demagnetizing field is small and high inductance can be obtained. Further, this effect is effective in the high frequency region because the distance between the insulating films 13 between the first and second strip-shaped magnetic material film rows can be narrowed and the number of strip-shaped magnetic material film rows can be increased. . In the above-mentioned embodiment, the case where the magnetic film row is a single layer is shown, but it may be a multi-layer laminated magnetic film. At this time, an insulating film may be formed on the magnetic film and the magnetic film may be repeatedly formed to form an inductance by using the multilayer magnetic film.

<Effects of the Invention> As described above, according to the present invention, since the strip-shaped magnetic film rows are arranged in close proximity to each other and in parallel with each other on almost the same plane, the leakage magnetic flux can be reduced and the layers can be stacked at high density. From that,
It is possible to obtain a high-density inductor having a high inductance value.

[Brief description of drawings]

FIG. 1 is a perspective view of a thin film inductor having a single layer of parallel magnetic films according to an embodiment of the present invention, and FIG. 2 is a- of FIG.
A sectional view taken along line b and FIG. 3 are perspective views of a general thin film inductor. 11 ... Insulating substrate, 12 ... Conductor film, 13 ... Insulating film,
14 ... First magnetic film row, 15 ... Second magnetic film row.

Claims (2)

[Claims] 1. A thin film inductor comprising a plurality of first strip-shaped magnetic material film arrays arranged on an insulating substrate and a plurality of strip-shaped conductor films surrounding the magnetic material film array so as to excite the magnetic material film array. A thin film inductor, wherein a second strip-shaped magnetic material film row is arranged in parallel with the first strip-shaped magnetic material film row and in close proximity to substantially the same plane. 2. The thin film inductor according to claim 1, wherein the strip-shaped magnetic film row is a laminated magnetic film.