JPS62120615A - Thin film electro-magnetic converter and signal transmitting/receiving method therefrom - Google Patents

Abstract

PURPOSE:To improve th reliability of a device and to read out the contents stored in a card including a semiconductor memory by arranging a ring-like soft magnetic film on a base so as to be parallel with the base, notching a part of the ring part to form a magnetic gap and winding a thin film oil around the ring-like soft magnetic film to form a thin film electro-magnetic converter. CONSTITUTION:The notched part 3 is formed on the ring-like soft magnetic film 2 to form the magnetic gap. On the other hand, the coil 4 consisting of a thin film is wound around the magnetic film 2 plural times. A head 5 is set up so as to be positioned just over the notched part 3 to be the magnetic gap when a card is set up in a reader and arranged on a prescribed position and the output terminal of the semiconductor memory built in the card is connected to the terminals 4a, 4b of the coil 4 through an amplifier or the like, so that a signal outputted from the memory excites the coil 4 and leaked magnetic flux appears on the notched part 3 to be the magnetic gap. The leaked magnetic flux is detected by the reproducing head 5 and an electrical signal once converted into a magnetic signal by the electro-magnetic converter is extracted again from the coil 6 of the head 5 as an electrical signal.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a thin film electromagnetic transducer and a method for transmitting and receiving signals therefrom.

[Technical background of the invention]

In recent years, small-sized, large-capacity information storage devices have been researched and developed in response to an increase in the amount of information that must be stored and demands for ease of handling. For example, attempts have been made to incorporate semiconductor memory into credit card-sized cards to dramatically increase their storage capacity compared to conventional cards with magnetic stripes attached.

[Problems with background technology]

Conventionally, in order to read the memory contents from a card containing the semiconductor memory mentioned above (or write the specified contents of the memo IJK), the terminals on the writing/reading device side and the terminals provided on the card side were mechanically connected. Was. While sulking,
Considering the number of times the card was used, the environment in which it was used, etc., there was a problem with the reliability of the contacts. In addition, since the stored contents of cards incorporating this semiconductor memory cannot be read by conventional card reading devices with magnetic stripes, there is a problem in that a new reading device is required.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned points, and there is no problem with the reliability of the contacts, and even a conventional card reading device can read the contents stored on the card with only slight improvements. The purpose is to provide a thin film electromagnetic transducer. Another object of the present invention is to provide a method for reading signals using this thin film electromagnetic transducer. [Summary of the Invention] In the present invention, a ring-shaped soft magnetic film is formed so that the plane formed by the ring is approximately parallel to the substrate. A thin film electromagnetic transducer is constructed by placing the thin film on a substrate, cutting out a part of the ring part, creating a magnetic air gap in this cutout part, and winding the thin film around the ring-shaped soft cloudy film several times. This is what I did. In addition, the thin film electromagnetic transducer (t) is arranged to face the magnetic gap in order to transmit and receive signals. be.

[Embodiments of the invention]

The following one is E! An embodiment of a thin film electromagnetic transducer called AK will be explained based on FIG. f.

FIG. 1 shows one embodiment of the present invention, in which (1) is a non-magnetic substrate, which is built into a credit card size card. The thickness of this substrate (1) is approximately 0.4fi. (2) is a ring-shaped soft magnetic film (for example, a film of FeNi, etc.), and is provided with a notch (3), which becomes a magnetic gap. The outer diameter of the ring of this magnetic film (2) is approximately 5 m, the inner diameter is approximately 4 m, and the thickness (core thickness) is approximately 10 m.
It is μm. A coil (4) made of a thin film is wound around the magnetic U f2) in a plurality of turns. In addition, (4
a) and (4b) are coil (4) terminals, which are connected to a semiconductor memory (not shown) built into the card.

Here, a method of reading memory contents using the electromagnetic transducer described above will be explained. Reference numeral (5) denotes a reproducing head for reading the information, and is arranged at a predetermined location of the reader (not shown). This head (5) is set so as to be located directly above the notch (3) that forms a magnetic gap when a card is set (inserted, etc.) in this reader and placed in a predetermined position. The output end of the semiconductor memory contained in the card is connected to the terminals (4a) and (4b) of the coil (4) via an amplifier, etc., so that the signal from the memory is transmitted to the coil (4). Encourage.

The magnetic flux leaks into the notch (3) which becomes a magnetic gap. This leakage magnetic flux is detected by the reproducing head (5), converted into a magnetic signal by an electromagnetic transducer, and the electric signal is again extracted as an electric signal from the coil (6) of the head (5).

Note that the length W of the notch (3) of the electromagnetic transducer is required to be approximately 011n. The reason for this is that, considering the flexibility of the card incorporating this, the positional accuracy of the electromagnetic transducer and the reproducing head (5) is considered to be about 0.1a. In addition, the inner diameter (approximately 4 mm) of the ring-shaped soft magnetic film (2) has a magnetic gap of about 0.1 mm, which is much larger than a normal magnetic head, so in order to reduce leakage of magnetic flux outside of the magnetic gap, This is determined based on the fact that the inner diameter of the magnetic path needs to be approximately several ten times the length of the gap and notch length W).

Next, an example of a method for manufacturing the electromagnetic transducer shown in FIG. 1 will be explained based on FIG. 2. First, as shown in FIG. FeNi, FeAA'8i, C
A magnetic thin film αυ of o-based amorphous or the like is formed to have a thickness of approximately 10 μm and to form approximately half of a ring shape. Next, as shown in the same figure (b), an 8i0z film α was added to
It is formed to be thick and smooth, and the surface is flattened. SaraKCu,
A conductor such as AI is formed to a thickness of about 1 μm and etched into a spiral coil shape as shown in FIG. 3C to form a coil (4). Further, an 8i0z film [13] is formed to a thickness of about 3 μm over the entire surface for insulating the coil (4). As shown in Figure (d), the end (11a) of the magnetic thin film αυ
) and (11b) are removed by etching to expose the thin film Ql) which will become the core surface.

Finally, the magnetic thin film Q41, u which becomes the remaining part of the ring
s is formed by the same process as the magnetic thin film αD. Here, since the ends (lla) and (llb) of the thin film αB are exposed first, the thin films αυ and α4), ([51] are completely connected. In this case, the coil (4) is a ring-shaped The magnetic films α, αυ, (L9 are wound multiple times).

Note that (4a) and (4b) are bonding areas for bonding a wiring connection wire from the semiconductor memory side to the coil (4).

In the present invention, the shape of the soft magnetic film is approximately ring-shaped, but the ring shape may also be as shown in FIG. 3, for example. That is, in this case, the (to) and (c) parts connected to the notch Cυ are two rings (R1
, R2). Even with this shape, the notch (21) has 1 flowing through the coil QJ.
! A leakage magnetic flux is generated due to the current, and this can be detected by a reproducing head similar to that shown in FIG.

〔Effect of the invention〕

As mentioned above, according to Himi #Jl/(according to 4!!), it is highly reliable because it is not necessary to send and receive signals through contacts, and even conventional card reading devices can be used with built-in semiconductor memory by making slight improvements. You can read the contents of the card.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an embodiment of a thin film electromagnetic transducer according to the present invention, FIG. 2 is a diagram showing an example of a method for manufacturing the thin film electromagnetic transducer of FIG. 1, and FIG. It is a perspective view showing an example of this. DESCRIPTION OF SYMBOLS 1... Non-magnetic substrate, 2... Ring-shaped soft magnetic film, 3... Notch, 4... Coil, 5... Reproduction head. Agent Patent Attorney Nori Ken Yudo Uji Hiroki Uji Prisoner 3 Figure 28

Claims (2)

[Claims] (1) a ring-shaped soft magnetic film arranged on a substrate so that the plane formed by the ring is substantially parallel to the substrate surface, and a part of the ring is cut out, and this cutout becomes a magnetic gap; A thin film electromagnetic transducer comprising a thin film coil wound around the ring-shaped soft magnetic film a plurality of times. (2) A method of transmitting and receiving signals using the thin-film electromagnetic transducer described in the previous section, in which a signal current passed through the thin-film coil of the thin-film electromagnetic transducer is applied to the magnetic gap of the thin-film electromagnetic transducer. A method for transmitting and receiving signals from a thin film electromagnetic transducer, characterized in that leakage magnetic flux generated is detected by a magnetic head disposed at a position facing the substrate surface and facing the magnetic gap.