JP2000011349A - Thin film device with electrostatic destruction preventing means - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin film device capable of easily constituting and releasing an electrostatic destruction preventive function and easily additionally fitting an electrostatic destruction preventing means. SOLUTION: This thin film device is provided with a thin film element 1, at least two lead conductors 21, 22 and a switch means 3. The lead conductors 21, 22 whose one ends are connected to the thin film element 1, and the other ends are connected to output terminals 41, 42. The switch means 3 is connected between the lead conductors 21-22, and switching operation is executed by energy S1 imparted from the outside to prevent the electrostatic destruction of the thin film element 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a thin film device having means for preventing electrostatic breakdown.

[0002]

2. Description of the Related Art Various thin-film devices such as semiconductor integrated circuit devices and thin-film magnetic transducers have extremely small current capacities. For this reason, in a manufacturing and assembling process, when an electrostatic charge charged to a human body of a worker who handles a thin film element is applied to the thin film element, an overcurrent flows through the thin film element, and electrostatic breakdown easily occurs. . Further, various characteristics of the thin film element may change due to an overcurrent, a magnetic field or heat generated due to the overcurrent.

As a specific example, a thin film magnetic head using a magnetoresistive film as a reading element will be described as an example. In thin-film magnetic heads, as a means for responding to higher sensitivity and higher output of a magnetoresistive film, a magnetic multilayer film having a high magnetoresistive effect formed by laminating a magnetic layer and a nonmagnetic layer attracts attention. It has been put to practical use. Among magnetic multilayer films, a spin valve film has attracted the most attention due to its high reproduction sensitivity. Known examples of spin valve films include, for example, PHYSICAL REVIEW B
43, 1297, 1991, Journal of applied physics 69
Vol., Page 4774, 1991, JP-A-4-358310.

A typical spin valve film is NiFe / Cu / (NiFe
or Co) / FeMn. In a spin valve film, a magnetic layer (Pined layer) in contact with an antiferromagnetic layer (Pin layer)
Layer), while the magnetization of the other magnetic layer (free layer) is freely rotated by an external magnetic field,
By realizing the antiparallel state of magnetization, a high magnetoresistance effect can be obtained.

However, the spin valve film has a very small current capacity. Therefore, in the manufacturing and assembly process,
When an electrostatic charge, which is charged on a human body of a worker who handles the magnetic head assembly, is applied to the magnetic head assembly, an overcurrent flows through the spin valve film, and electrostatic breakdown easily occurs.

In the spin valve film, the magnetoresistance effect is determined by the relative rotation angle of the magnetization direction of the free layer with respect to the fixed magnetization direction of the pinned layer in contact with the antiferromagnetic layer. When the electrostatic charge jumps into the spin valve film having such a structure, the fixed magnetization direction of the pinned layer changes due to the moving direction of the charge, or a magnetic field or heat generated due to the movement of the charge. . If the fixed magnetization direction of the pin layer changes, the degree of the magnetoresistance effect changes, and a predetermined reproduction characteristic cannot be obtained.

As means for preventing electrostatic breakdown in a thin film magnetic head, JP-A-7-85422 discloses that an inductive type thin film element and a magnetoresistive type thin film element are short-circuited with a substance of 10 ³ to 10 ⁹ Ωcm. Also disclosed is a technique for connecting at least one or more diodes between a pair of terminals connected to the magnetoresistive film. The problem of this prior art is that in the manufacturing process of the magnetic head, a resistive substance for short-circuiting the inductive type thin film element and the magnetoresistive type thin film element must be provided therein.

Japanese Patent Application Laid-Open No. Hei 7-141636 discloses a configuration in which a flexible printed circuit board is used as a lead conductor for a magnetoresistive effect film. Short-circuit the terminals,
A technique for cutting a flexible printed circuit board to open a short-circuit portion before a characteristic measuring operation after an assembling operation is disclosed. The characteristic measurement operation is performed in a state where the flexible printed circuit board is cut to open the short-circuited portion.

The problem of this prior art is that, in order to prevent electrostatic charging that may occur after the characteristic measuring operation and the accompanying electrostatic destruction, the electrostatic destruction preventing means once released in the characteristic measurement is used. In that it must be reconfigured. For example, during the transportation process from the manufacturer to the user, at the time of the acceptance inspection by the user, and also at the time of assembling to the magnetic disk device, there is a risk of causing the electrostatic charge and the resulting electrostatic breakdown and characteristic change. In order to avoid this, it is necessary to reconfigure the electrostatic breakdown preventing means once released in the characteristic measuring operation.

[0010]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a thin film device which can easily carry out the construction and release of an electrostatic discharge protection function.

Another object of the present invention is to provide a thin film device which can easily attach an electrostatic discharge preventing means to a thin film element.

[0012]

In order to solve the above-mentioned problems, a thin-film device according to the present invention includes a thin-film element, at least two lead conductors, and at least one switch. The lead conductor is connected to the thin film element. The switch means is connected to the lead conductor and performs a switching operation by externally applied energy to prevent electrostatic breakdown of the thin film element.

In the above-described thin film device, since the lead conductor is connected to the thin film element, a signal output from the thin film element or a signal input to the thin film element can be performed through the lead conductor.

The switch means performs a switching operation by externally applied energy. Therefore, by supplying or stopping the supply of energy to the switch means from the outside, the switch means can perform a switching operation.

The switch means is connected to the lead conductor,
The switching operation prevents the electrostatic breakdown of the thin film element. Specifically, according to the switching operation of the switch means, the lead conductors connected to the thin film element are short-circuited, or the circuit loop including the lead conductor and the thin film element is opened. For this reason, in the manufacturing and assembling processes, even if the electrostatic charge charged on the worker's body jumps into the lead conductor, no overcurrent flows through the thin film element. Therefore, it is possible to prevent electrostatic breakdown and characteristic change of the thin film element. The means for supplying energy to the switch means may be provided in the thin film device itself, or may be provided separately from the thin film device.

In the transportation process from the manufacturer to the user, during the acceptance inspection by the user, and also during the assembling to the magnetic disk device, it is possible to prevent the charging, the electrostatic breakdown and the characteristic change accompanying the charging.

When a signal is supplied to a thin film element or a signal is extracted from the thin film element for a characteristic measuring operation or the like,
By supplying energy to the switch means or stopping the supply of energy, a normal signal transmission line can be formed from the thin film element to the output terminal.

As described above, the configuration and release of the electrostatic breakdown prevention function can be executed by a simple operation of simply supplying or stopping the supply of energy to the switch means from the outside. Moreover, the electrostatic breakdown preventing function can be easily added to the thin film element only by externally attaching the switch means.

A preferred example of the switching means constituting the electrostatic breakdown preventing means is a thermistor element having a positive temperature coefficient of resistance (hereinafter referred to as a PTC thermistor element). P
Energy for controlling the TC thermistor element is given as thermal energy. The PTC thermistor element may be directly heated by the heating means.

As another means, a heating PTC thermistor element may be provided, and the heating PTC thermistor element may apply heat energy to the PTC thermistor element constituting the switch means.

The switching means may include a thermistor element having a negative resistance temperature characteristic (hereinafter referred to as an NTC thermistor element).

The switching means may include a semiconductor switch. In this case, the semiconductor switch may be a combination of a phototransistor and a light emitting element (photocoupler), a phototransistor, or a three-terminal switch element. Further, as another aspect, a mechanical switch means may be included.

In the present invention, the thin film element may be a semiconductor integrated circuit element or a magnetoresistive film. When the thin film element is made of a magnetoresistive film, the present invention can be applied to a magnetoresistive film having a multilayer structure to obtain a great effect. A typical example of a magnetoresistive film having a multilayer structure is a magnetoresistive film having a spin valve film structure. Such a magnetoresistive film is used as a reproducing element of a thin film magnetic head.

[0024]

FIG. 1 is a diagram schematically showing a configuration of a thin film device according to the present invention. As shown, the thin-film device according to the present invention includes a thin-film element 1, at least two lead conductors 21 and 22, and switch means 3. The thin film element 1 is connected to one ends of the lead conductors 21 and 22. The other ends of the lead conductors 21 and 22 are output terminals 41 and 4.
It is led to 2.

Switch element 3 constituting switch means 3
Reference numeral 1 denotes a circuit connected between the lead conductors 21 and 22 for performing a switching operation by energy S1 given from the outside and preventing electrostatic breakdown of the thin film element.

In the thin film device described above, the lead conductor 2
Since one end of each of the thin film elements 1 and 22 is connected to the thin film element 1 and the other end is connected to each of the output terminals 41 and 42, the signal output from the thin film element 1 or the supply of the signal to the thin film element 1 is output. This can be performed through the terminals 41 and 42 and the lead conductors 21 and 22.

The switching element 31 performs a switching operation by the energy S1 given from the outside. Therefore, by supplying or stopping the supply of the energy S1 to the switch element 31 from the outside, the switching means 3 can perform the switching operation.

In the case of the embodiment, since the switch element 31 constituting the switch means 3 is connected between the lead conductors 21 and 22, when the switch element 31 is closed by the energy S1 from the outside, a thin film is used. The switch element 31 short-circuits between the lead conductors 21 and 22 connected to the element 1. Therefore, in the manufacturing and assembly process,
The static charge charged on the worker's body is output terminal 41,
Even when jumping from 42, it is short-circuited by the switch means 3 and does not flow into the thin film element 1. Therefore, it is possible to prevent the electrostatic breakdown and characteristic change of the thin film element 1.

In the transportation process from the manufacturer to the user, at the time of the acceptance inspection by the user, and at the time of assembling to the magnetic disk drive, as long as the switch element 31 is kept closed, the charging and the accompanying electrostatic charge are performed. Destruction and characteristic change can be prevented.

When a signal is supplied to the thin-film element 1 or a signal is extracted from the thin-film element 1 for a characteristic measuring operation or the like, the switching element 31 may be supplied with energy S1 for opening. Thus, a normal signal transmission line is formed between the thin film element 1 and the output terminals 41 and 42, so that a characteristic measuring operation can be performed.

As described above, the configuration and release of the electrostatic breakdown prevention function can be executed by a simple operation of simply supplying the energy S1 to the switch element 31 from the outside or stopping the supply. Moreover, the electrostatic breakdown preventing function can be easily added to the thin film element 1 simply by attaching the switch element 31 externally.

FIG. 2 is a view showing a specific embodiment of the thin film device according to the present invention. In the figure, the same components as those shown in FIG. 1 are denoted by the same reference numerals. In this embodiment, the switch means 3 is a PTC
It consists of a thermistor element 31. Energy S1 to the PTC thermistor element 31 is given as thermal energy. In the case of the embodiment, the PTC thermistor element 31 is directly heated by the heating means.

The switching means 3 is a PTC thermistor element 3
1 is advantageous in that the PTC thermistor element 31
Operates as a low-resistance element (for example, several ohms) at normal temperature, which causes a short circuit between the lead conductors 21 and 22. Therefore, there is no need to supply energy S1 from the outside to prevent electrostatic breakdown. It is. This means that in various situations where electrostatic charging may occur, for example, in the manufacturing and assembly process, in the transportation process from the manufacturer to the user, during acceptance inspection by the user, and during assembly into the magnetic disk drive, Without giving energy S1 from outside,
This means that charging, and electrostatic breakdown and characteristic changes accompanying the charging can be prevented.

FIG. 3 is a view showing still another embodiment of the thin film device according to the present invention. In the figure, the same components as those shown in FIG. 1 are denoted by the same reference numerals. In the embodiment, a heating PTC thermistor element 32 is provided in addition to the PTC thermistor element 31 used as the switch means 3. Heat energy is given to the PTC thermistor element 31 by the heating PTC thermistor element 32. The heating PTC thermistor element 32 is driven by an electric signal S1 supplied from the outside.

FIG. 4 is a view showing still another embodiment of the thin film device according to the present invention. In the figure, the same components as those shown in FIG. 1 are denoted by the same reference numerals. In the embodiment, the switching means 3 includes thermistor elements 311 and 312 having a negative temperature coefficient of resistance (hereinafter referred to as NTC thermistor elements). NT
The C thermistor elements 311 and 312
22 in series. In the embodiment, two NTs
Although the C thermistor elements 311 and 312 are shown, the number may be one or two or more.

The switching means 3 is an NTC thermistor element 3
11, 312, the drive timing is PT
It is the reverse of the C thermistor element. That is, the NTC thermistor elements 311 and 312 have a high resistance at room temperature and are in an open state. To perform the closing operation, heat energy may be applied.

As described above, the NTC thermistor element 31
1 and 312 have a high resistance at room temperature and are in an open state. Therefore, when it is necessary to prevent electrostatic breakdown, the NTC thermistor elements 311 and 312 are kept at room temperature. In this state, in the manufacturing and assembling processes, even if the electrostatic charge charged to the worker's body jumps from the output terminals 41 and 42, the NTC thermistor elements 311, 3 having a high resistance value.
As a result, the current limiting function of the thin film element 12 works, and no overcurrent flows through the thin film element 1. Therefore, it is possible to prevent the electrostatic breakdown and characteristic change of the thin film element 1.

In the transportation process from the manufacturer to the user, at the time of the acceptance inspection by the user, and also at the time of assembling into the magnetic disk device, it is possible to prevent the charging, the electrostatic breakdown and the characteristic change accompanying the charging.

When a signal is supplied to the thin-film element 1 or a signal is extracted from the thin-film element 1 for a characteristic measuring operation or the like, heat energy may be supplied to the NTC thermistor elements 311 and 312. As a result, the resistance values of the NTC thermistor elements 311 and 312 decrease, and the thin film element 1
Since a normal signal transmission line is formed between the output terminal 41 and the output terminals 41 and 42, a characteristic measuring operation can be performed.

As described above, a simple operation of supplying heat energy or stopping the supply of heat to the NTC thermistor elements 311 and 312 constituting the switch means 3 to prevent electrostatic breakdown. Configuration and release of functions can be performed.

Switch means 3 is NTC thermistor element 3
The advantage of the configuration of the NTC thermistor elements 311 and 312 is that the NTC thermistor elements 311 and 312 operate as a high-resistance element at normal temperature, thereby limiting the current flowing through the thin-film element 1. There is no need to supply heat energy from outside. This means that in various situations where electrostatic charging may occur, for example, in the manufacturing and assembly process, in the transportation process from the manufacturer to the user, during acceptance inspection by the user, and during assembly into the magnetic disk drive, This means that electrification and the accompanying electrostatic breakdown and characteristic change can be prevented without applying external thermal energy.

FIG. 5 is a view showing still another embodiment of the thin film device according to the present invention. In the figure, the same components as those shown in FIG. 1 are denoted by the same reference numerals. In the embodiment, heat energy is applied to the NTC thermistor elements 311 and 312 used as the switch means 3 by the heating PTC thermistor element 32. The PTC thermistor element for heating 32 is driven by an electric signal supplied from the outside through terminals 43 and 44.

FIG. 6 is a view showing still another embodiment of the thin film device according to the present invention. In the drawings, the same components as those shown in FIGS. 1 to 5 are denoted by the same reference numerals. The feature of this embodiment is that the switch means 3
As NTC thermistor elements 311, 312 and PT
The C thermistor element 313 is included. The NTC thermistor elements 311 and 312 are connected to the lead conductors 21 and 22 in series. The PTC thermistor element 313 is connected between the output terminals 41 and 42.

In a situation where it is necessary to prevent electrostatic breakdown,
The NTC thermistor elements 311 and 312 and the PTC thermistor element 313 are kept at room temperature. In this state, even if an electrostatic charge charged on the human body of the worker jumps from the output terminals 41 and 42 in the manufacturing and assembling processes, the NTC
The current limiting action of the thermistor elements 311 and 312 and the short-circuit action of the PTC thermistor element 313 work, so that no overcurrent flows through the thin film element 1. Therefore, it is possible to prevent the electrostatic breakdown and characteristic change of the thin film element 1.

Further, in the case of the embodiment, the NTC thermistor elements 311 and 312 which operate as a high resistance at room temperature are used.
Are connected in series to the thin-film element 1 and this series circuit is connected in parallel to the PTC thermistor element 313.
1, 312 and the thin film element 1 are more easily flowed to the PTC thermistor element 313 than the series circuit. For this reason, it is possible to more reliably prevent electrostatic breakdown and characteristic changes of the thin film element 1.

When a signal is supplied to the thin-film element 1 or a signal is extracted from the thin-film element 1 for a characteristic measuring operation or the like, heat energy is supplied to the NTC thermistor elements 311, 312 and the PTC thermistor element 313. As a result, the resistance values of the NTC thermistor elements 311 and 312 decrease, and the resistance value of the PTC thermistor element 313 increases sharply to be in an open state. A signal transmission line is configured.

FIG. 7 is a view showing still another embodiment of the thin film device according to the present invention. In the drawings, the same components as those shown in FIGS. 1 to 6 are denoted by the same reference numerals. In the embodiment, the switch means 3 is
It includes a phototransistor 311 and a light emitting element 33. The phototransistor 311 is a lead conductor 21-2.
It is connected between the two. According to this embodiment, the terminal 4
By supplying or stopping the supply of the electric signal S1 to the light emitting elements 3 and 44, the light emitting element 33 emits or extinguishes light,
Thus, the phototransistor 311 can perform a switching operation.

In a situation where it is necessary to prevent electrostatic breakdown,
The electric signal S1 is supplied to the terminals 43 and 44, and the light emitting element 33 is supplied.
To keep the phototransistor 311 on. In this state, an overcurrent does not flow through the thin-film element 1 even when an electrostatic charge charged on the human body of the worker jumps from the output terminals 41 and 42 in the manufacturing and assembly processes. Therefore, it is possible to prevent the electrostatic breakdown and characteristic change of the thin film element 1.

When supplying a signal to the thin film element 1 or extracting a signal from the thin film element 1 for a characteristic measuring operation or the like, the supply of the electric signal S1 to the terminals 43 and 44 is stopped and the light emitting element 33 is turned off. Let it. As a result, the phototransistor 311 is turned off, so that a normal signal transmission line can be formed between the thin film element 1 and the output terminals 41 and 42. The thin film device according to the present invention may include only a phototransistor and emit or extinguish light from an external light source.

FIG. 8 is a view showing still another embodiment of the thin film device according to the present invention. In the drawings, the same components as those shown in FIGS. 1 to 7 are denoted by the same reference numerals. In this embodiment, the switch means 3
A three-terminal switch element 31 is included. The three-terminal switch element 31 is configured by a bipolar transistor, a field effect transistor, or the like, and is connected between the lead conductors 21 and 22. In the embodiment shown in FIG. 8, the control method of the three-terminal switch element 31 is the same as the control method of the phototransistor of FIG. 7, and has substantially the same operation and effect as the embodiment of FIG.

FIG. 9 is a view showing still another embodiment of the thin film device according to the present invention. In the drawings, the same components as those shown in FIGS. 1 to 8 are denoted by the same reference numerals. In the embodiment, the switch means 3 is
It includes semiconductor switches 311, 312. The illustrated semiconductor switches 311 and 312 are three-terminal switching elements, and are controlled by electric signals S1 and S2 supplied to terminals 43 and 44 connected to control electrodes.

In a situation where it is necessary to prevent electrostatic breakdown,
The three-terminal switch elements 311 and 312 are kept off. In this state, in the manufacturing and assembling processes, the electrostatic charges charged to the human body of the worker are output to the output terminals 41 and 42.
No overcurrent flows through the thin-film element 1 even if it jumps into the thin film element 1. Therefore, it is possible to prevent the electrostatic breakdown and characteristic change of the thin film element 1.

To supply a signal to the thin film element 1 or take out a signal from the thin film element 1 for a characteristic measuring operation or the like, control signals S1 and S2 are applied to control electrodes of the three-terminal switch elements 311 and 312. , Three-terminal switch element 31
1, 312 are made conductive. Thus, a normal signal transmission line is formed between the thin film element 1 and the output terminals 41 and 42.

FIG. 10 is a view showing still another embodiment of the thin film device according to the present invention. In the drawings, the same components as those shown in FIGS. 1 to 9 are denoted by the same reference numerals. In the embodiment, the phototransistor 3
11 and 312 and a light emitting element 33. According to this embodiment, the light emitting element 33 emits or extinguishes the light by the electric signal supplied to the terminals 43 and 44, whereby the phototransistors 311 and 312 can perform the switching operation.

The control timings of the phototransistors 311 and 312 are the same as in the case of the three-terminal switch element in FIG. 9, and have substantially the same functions and effects as in the embodiment in FIG.

FIG. 11 is a view showing still another embodiment of the thin film device according to the present invention. In the drawings, the same components as those shown in FIGS. 1 to 10 are denoted by the same reference numerals. This embodiment is characterized in that the phototransistors 311, 312 and P
It has a TC thermistor element 313. The phototransistors 311 and 312 are connected to the lead conductors 21 and 22 in series. The PTC thermistor element 313 is connected between the terminals 41 and 42. Although not shown, a light-emitting element for driving the phototransistors 311 and 312 is provided.

In a situation where it is necessary to prevent electrostatic breakdown,
The phototransistors 311 and 312 are kept off. Further, the PTC thermistor element 313 is kept at room temperature. In this state, the phototransistors 311 and 312 are turned off even when the electrostatic charge charged to the human body of the worker jumps from the output terminals 41 and 42 in the manufacturing and assembly processes. Since the element 313 is in a short-circuit state, no overcurrent flows through the thin-film element 1. Therefore, it is possible to prevent the electrostatic breakdown and characteristic change of the thin film element 1.

When supplying a signal to the thin film element 1 or extracting a signal from the thin film element 1 for a characteristic measuring operation or the like, the phototransistors 311 and 312 are turned on, and thermal energy is supplied to the PTC thermistor element 313. Supply. Thereby, the phototransistors 311 and 31
2 becomes conductive and the resistance value of the PTC thermistor element 313 increases sharply to open.
A normal signal transmission line is configured between the output terminals 41 and 42.

FIG. 12 is a view showing still another embodiment of the thin film device according to the present invention. In the drawings, the same components as those shown in FIGS. 1 to 11 are denoted by the same reference numerals. In this embodiment, the signal processing circuit 2
Contains 0. The signal processing circuit 20 is connected to the thin film element 1.

The feature of the embodiment shown in FIG.
That is, the switching means 3 is caused to perform a switching operation by thermal energy generated when 0 operates. In the embodiment, the switch means 3 is a PTC thermistor element 31
And the PTC thermistor element 31 has a terminal 41
-42.

In a situation where it is necessary to prevent electrostatic breakdown,
The PTC thermistor element 31 is kept at room temperature. In this state, the PTC thermistor element 31 is in a short-circuit state even when an electrostatic charge charged on the human body of the worker jumps from the output terminals 41 and 42 in the manufacturing and assembly processes. No overcurrent flows. Therefore,
It is possible to prevent electrostatic breakdown and characteristic change of the thin film element 1.

When a signal is supplied to the thin film element 1 or a signal is extracted from the thin film element 1 for a characteristic measuring operation or the like, the signal processing circuit 20 operates to generate heat. By this heating operation, the PTC thermistor element 31 is heated,
The resistance value of the C thermistor element 31 sharply increases and becomes an open state, and a normal signal transmission line is formed between the thin film element 1 and the output terminals 41 and 42.

In order to start the operation of the signal processing circuit 20, the PTC thermistor element 31 is set at the beginning of the characteristic measuring operation.
Is heated by an external heat source different from the signal processing circuit 20. Then, after the signal processing circuit 20 starts operating and its heat generation temperature rises to a temperature sufficient for operating the PTC thermistor element 31 in the high resistance region, it is preferable to exclusively use the heat generation of the signal processing circuit 20. .

The PTC thermistor element 31 is provided downstream of the signal processing circuit 20. Therefore, according to this embodiment, not only the thin film element 1 but also the signal processing circuit 20 can be prevented from being electrostatically damaged.

FIG. 13 is a view showing still another embodiment of the thin film device according to the present invention. In the drawings, the same components as those shown in FIGS. 1 to 12 are denoted by the same reference numerals. In this embodiment, the signal processing circuit 20
Contains. The switch unit 3 includes phototransistors 311, 312 and a light emitting element 33, and is provided at a subsequent stage of the signal processing circuit 20. Therefore, according to this embodiment, not only the thin film element 1 but also the signal processing circuit 2
0 electrostatic breakdown can be prevented.

Although not shown, the switch means 3 may be constituted by mechanical switch means 3. The mechanical switch means 3 may be of a type in which a mechanical contact is manually operated, or may be of a type in which the mechanical contact is opened and closed by a signal such as electric, magnetic, heat or light. The latter includes, for example, a coil-based relay, a reed relay, a thermal relay, and the like.

In the present invention, the thin film device 1 may be a semiconductor integrated circuit device or a magnetoresistive film. When the thin film element 1 is formed of a magnetoresistive film, the present invention is applied to a magnetoresistive film having a multilayer structure,
A great effect can be obtained. A typical example of a magnetoresistive film having a multilayer structure is a magnetoresistive film having a spin valve film structure. A magnetoresistive film having a spin valve film structure is used as a reproducing element of a thin film magnetic head. Next, an example in which the present invention is applied to a thin-film magnetic head device will be described.

FIG. 14 is a plan view of a magnetic head device according to the present invention. The magnetic head device according to the present invention includes a thin film magnetic head 5, a head support device 6, two sets of lead conductors (21, 22) and (71, 72), and a switch means 3.
And A circuit for preventing electrostatic breakdown by the switch means 3 is constituted by any of the embodiments shown in FIGS.

In the embodiment shown in FIG.
Are mounted on one surface of the head support 6. The switch means 3 includes lead conductors (21, 22) and (71, 72)
Are connected between the lead conductors 21-22. In mounting the switch means 3 on the head support device 6, a circuit board or a flexible wiring board may be used, or may be directly attached.

FIG. 15 is an enlarged front view of a magnetic head mounting portion of the magnetic head device shown in FIG. 14, and FIG.
FIG. 4 is an enlarged bottom view of a magnetic head mounting portion of the magnetic head device shown in FIG.

Referring to FIGS. 15 and 16, the thin-film magnetic head 5 has a slider 51 and thin-film elements 1 and 52. The slider 51 has a medium facing surface 511 on one side,
The opposite side is a support surface 512. The medium facing surface 511 of the slider 51 may have one to three rails, and may be a flat surface without the rails. Also,
In order to improve the flying characteristics, the medium facing surface 511 may have various geometric shapes. The present invention can be applied to any type of slider. The most protruding surface of the medium facing surface 511 forms an air bearing surface having a high surface property. The illustrated slider 51 has two rail portions 513 and 514 on the medium facing surface 511, and uses the surfaces of the rail portions 513 and 514 as the air bearing surface 510.

The thin film elements 1, 52 are arranged on the side surfaces of the slider 51, and take out electrodes 5 appearing outside the slider 51.
15, 516, 517 and 518. The thin-film elements 1 and 52 are disposed at the outflow end thereof when viewed in the medium traveling direction (air outflow direction) indicated by the arrow a. The thin film elements 1 and 52 are manufactured according to a process similar to the IC manufacturing technology.

FIG. 17 shows the thin film element 1 of the thin film magnetic head 5,
It is sectional drawing which expands and shows the part of 52. Thin film element 1,
Of the 52, the thin film element 1 is a reproducing element using a magnetoresistive film, and the thin film element 52 is an inductive recording element. Less than,
The thin film element 1 using the magnetoresistive film is called an MR element.

FIG. 18 is an enlarged sectional view showing a more detailed structure of the MR element 1 included in the thin-film magnetic head. A first magnetic shield film 82, an insulating film 83, and a first magnetic shield film 82 are formed on a base insulating film 81 laminated on a base 80 constituting the slider 51.
An R element 1, an insulating film 83, and a second magnetic shield film (first magnetic film) 521 are sequentially stacked.

Central active area 11 constituting MR element 1
May use a magnetic anisotropic magnetoresistive effect film, but is more preferably constituted by a spin valve film. The illustrated central active region 11 is formed of a spin valve film. The spin valve film includes a magnetic field responsive film (first ferromagnetic film) 111, a nonmagnetic film 112, a fixed magnetization film (second ferromagnetic film) 113, and an antiferromagnetic film 114
Contains. Needless to say, other film configurations other than the film configuration of the spin valve film can be adopted.

The central active region 11 composed of a spin valve film is formed with a track width of, for example, 2.5 μm or less, and has lead conductors 12 at both ends.
The lead conductor 12 includes a Co—Pt alloy film 121 and an electrode film 122. The Co—Pt alloy film 121 is provided for controlling a magnetic domain of the magnetic field responsive film 111 of the spin valve film by applying a longitudinal bias magnetic field to the spin valve film.

Specifically, the spin valve film has the following film configuration. First, the magnetic field response film 111 has a thickness of about 0.1 μm.
It is made of a NiFe film having a thickness of m. Under the magnetic field responsive film 111, a base film made of a Ta film having a thickness of about 0.05 μm is formed. Non-magnetic film 112 is about 0.025 μm
Is a Cu film having a thickness of The magnetization fixed film 113 is a NiFe film having a thickness of about 0.05 μm. The antiferromagnetic film 114 is formed of a FeMn film having a thickness of about 0.1 μm, and has a protective film of Ta having a thickness of about 0.05 μm. However, these film configurations and the numerical values of the film thickness are examples, and are not limited in any way, and other film configurations can be adopted.

As described above, the spin valve film has a multilayer thin film structure and has a very small current capacity. For this reason, in the manufacturing and assembling processes, when an electrostatic charge that is charged on the human body of a worker handling the magnetic head assembly is applied to the magnetic head assembly, an overcurrent flows through the spin valve film, and the electrostatic valve is easily discharged. Destruction will occur.

In the spin valve film, the magnetoresistance effect is caused by the magnetization fixed film (pinned film) in contact with the antiferromagnetic layer 114.
It is determined by the relative rotation angle of the magnetization direction of the magnetic field responsive film (free layer) 111 with respect to the fixed magnetization direction of the layer 113. When an electrostatic charge jumps into the spin valve film having such a structure, the magnetization fixed film (pined layer) 1 is moved by a moving direction of the charge and a magnetic field or heat generated due to the charge transfer.
13, the fixed magnetization direction changes. Magnetization fixed film (pi
If the fixed magnetization direction of the (ned layer) 113 changes, the magnetoresistive effect changes, and a predetermined reproduction characteristic cannot be obtained.

As shown in FIG. 17, the thin film element 52 serving as a recording element is composed of a lower magnetic film 5 serving also as an upper shield film.
21, an upper magnetic film 522, a coil film 523, a gap film 524 made of alumina or the like, an insulating film 525 made of an organic resin, a protective film 526, and the like. The tip portions of the lower magnetic film 521 and the upper magnetic film 522 are pole portions P1 and P2 opposed to each other with a very small gap film 524 therebetween, and writing is performed in the pole portions P1 and P2.

The lower magnetic film 521 and the upper magnetic film 522
Are connected to each other to complete a magnetic circuit at a back gap portion whose yoke portion is opposite to the pole portions P1 and P2. A coil film 523 is formed on the insulating film 525 so as to spiral around the joint of the yoke. Both ends of the coil film 523 are electrically connected to extraction electrodes 517 and 518 (see FIGS. 15 and 16).

Next, the head supporting device 6 is shown in FIGS.
And 16, the one end in the longitudinal direction is a fixed end, the other end is a free end, and has a flexible support portion 61 on the free end side. Is mounted on the support surface 512 of the. Head support device 6
Are thin film magnetic heads 5 so that the thin film magnetic heads 5 can follow the surface fluctuation of a magnetic disk (not shown).
I support. Various types of such head support devices have been proposed and put into practical use. In the illustrated head support device 6, the flexible support portion 6
Reference numeral 1 denotes a gimbal which allows a roll motion about a first axis taken in the longitudinal direction and a pitch motion about a second axis orthogonal to the first axis. The support surface 512 of the slider 51 is connected by, for example, bonding.

The lead conductors (21, 22), (71, 7)
In 2), the lead conductors 21 and 22 are provided for the MR element 1, and the lead conductors 71 and 72 are provided for the thin film element 52 serving as a recording element. Lead conductor 2
1, 22 are twisted. Such lead conductors 21 and 22 are generally called a twisted pair wire. One end of each of the lead conductors 21 and 22 is connected to the MR element 1. Specifically, the lead conductor 21,
22 are provided with extraction electrodes 515 and 516 (FIG. 1).
5, see FIG. 16) and conducts to the end passive regions 121 and 122 of the MR element 1 shown in FIG. Between the lead conductors 21 and 22, at an intermediate portion in the length direction,
The switch means 3 mounted on the head support device 6 is connected.

In the embodiment, the lead conductors 71 and 72 are also constituted by twisted pair wires. Lead conductor 71, 7
2 are connected to extraction electrodes 517 and 518 (FIGS. 15 and 1).
6), and the thin film element 52 constituting the recording element
(See FIG. 17).

FIG. 19 is an electrical connection diagram of the magnetic head device shown in FIGS. As shown in the figure, the MR element 1 composed of a spin valve film has lead conductors 21 and 2
The switch means 3 is guided to output terminals 41 and 42 by a switch 2 and is connected between the lead conductors 21 and 22. Therefore, in the manufacturing and assembling processes, even if the electrostatic charge charged to the human body of the worker jumps from the output terminals 41 and 42, it is short-circuited by the switch means 3 and does not flow to the MR element 1. For this reason, it is possible to prevent electrostatic destruction and characteristic changes of the MR element 1.

In the transportation process from the manufacturer to the user, in the acceptance inspection by the user, and in the assembling to the magnetic disk device, etc., as long as the switch means 3 is kept in the closed state, the charging and the accompanying electrostatic charge are performed. Destruction and characteristic change can be prevented.

When a signal is supplied to the MR element 1 or a signal is extracted from the MR element 1 for a characteristic measuring operation or the like, the switch means 3 may be supplied with energy S1 for opening. Thus, a normal signal transmission line is formed between the MR element 1 and the output terminals 41 and 42, so that a characteristic measuring operation can be performed.

As shown in the embodiment, when the MR element 1 is made of a spin valve film, the current capacity of the spin valve film is extremely small.
When an electrostatic charge, which is charged on the human body of a worker who handles the magnetic head assembly, is applied to the magnetic head assembly, an overcurrent flows through the spin valve film, which easily causes electrostatic breakdown. According to the embodiment to which the present invention is applied, electrostatic breakdown of the spin valve film can be reliably prevented.

When an electrostatic charge jumps into the spin valve film, the magnetization fixed film (pined layer) 11 is moved by the moving direction of the charge and the magnetic field or heat generated due to the charge transfer.
The fixed magnetization direction of No. 3 changes, the magnetoresistive effect changes, and a predetermined reproduction characteristic cannot be obtained. According to the embodiment to which the present invention is applied, such a problem can be solved.

Next, another embodiment of the thin-film magnetic head device will be described with reference to FIGS. FIG. 20 is a plan view showing another embodiment of the magnetic head device according to the present invention, and FIG. 21 is an electric circuit diagram of the magnetic head device shown in FIG. The embodiment shown in FIGS. 20 and 21 shows a magnetic head device to which the thin film device shown in FIG. 3 is applied. A substrate 30 is mounted on a side portion of the head support device 6, and a PTC thermistor element 31 and a heating PTC thermistor element 32 constituting the switch means 3 for preventing electrostatic breakdown are mounted on the substrate 30. Terminals 71, 7 for the recording element 52 (see FIGS. 17 and 21) are provided on the substrate 30.
2. Terminals 41 and 42 for MR element 1 and PT for heating
Terminals 43 and 44 for the C thermistor element 32 are provided. The PTC thermistor element 31 has terminals 41, 4
2 are connected. The head support device 6 can be configured using, for example, a flexible wiring board such as a tab tape.

The action of preventing the electrostatic breakdown and characteristic change of the MR element 1, which is a thin film element, and handling during the characteristic measuring operation are the same as those of the thin film device shown in FIG. Immediately before or after incorporating into a magnetic recording / reproducing device,
The substrate 30 is cut along a cutting line XX to separate the PTC thermistor elements 31 and 32 from the circuit of the MR element 1.

FIG. 22 is a plan view showing still another embodiment of the magnetic head device according to the present invention. 20 and 21 is that the PTC thermistor element 31 and the heating PTC thermistor element 32 that constitute the switch means 3 are different from the embodiment of FIGS.
Is mounted on the head support device 6. When the head support device 6 is formed of a flexible wiring board such as a tab tape, the above-described PT
The arrangement of the C thermistor elements 31 and 32 can be easily realized. Except for this difference, it is the same as the embodiment of FIGS.

FIG. 23 is a plan view showing another embodiment of the magnetic head device according to the present invention, and FIG. 24 is an electric circuit diagram of the magnetic head device shown in FIG. 23 and 24 also show a magnetic head device to which the thin film device shown in FIG. 3 is applied. PTC thermistor element 31 and PTC thermistor element 32 for heating constituting switch means 3
Are mounted on the head support device 6. The PTC thermistor element 31 is connected to the lead conductors 21 and 22 connected to the MR element 1 at terminals 45 and 46.

The terminals 71 and 72 for the recording element 52 (see FIG. 24) are constituted by conductors formed on a rigid substrate 70. Terminals 41 and 42 for MR element 1
Is also formed by a conductor formed on the hard substrate 40. These substrates 70 and 40 can be used as connectors to be inserted into a measuring device (not shown) at the time of characteristic measurement.

The action of preventing the electrostatic breakdown and characteristic change of the MR element 1 which is a thin film element, and the handling at the time of the characteristic measurement operation are the same as those of the thin film device shown in FIG.

FIG. 25 is a plan view showing another embodiment of the magnetic head device according to the present invention, and FIG. 26 is an electric circuit diagram of the magnetic head device shown in FIG. The embodiment shown in FIGS. 25 and 26 also shows a magnetic head device to which the thin film device shown in FIG. 3 is applied. Terminals 71 and 72 for the recording element 52 (see FIG. 26), and terminals 41 for the MR element 1,
Reference numeral 42 is formed on the hard substrates 70 and 40. These substrates 70 and 40 can be used as connectors to be inserted into a measuring device (not shown) at the time of characteristic measurement.

The PTC thermistor element 31 constituting the switch means 3 is connected to terminals 41 and 42 for the MR element 1 formed on the substrate 40. The heating PTC thermistor element 32 is thermally coupled to the PTC thermistor element 31.

The action relating to the prevention of electrostatic breakdown and characteristic change of the MR element 1 which is a thin film element, and the handling at the time of the characteristic measurement work are the same as those of the thin film device shown in FIG. Immediately before or after assembling into the magnetic recording / reproducing device, the substrate 30 is cut along the cutting line XX, and the PTC thermistor element 31 is separated from the substrate 40.

FIG. 27 is a plan view showing another embodiment of the magnetic head device according to the present invention, and FIG. 28 is an electric circuit diagram of the magnetic head device shown in FIG. The embodiment shown in FIGS. 27 and 28 shows a magnetic head device to which the thin film device shown in FIG. 4 is applied. Terminals 71 and 72 for the recording element 52 (see FIG. 28), and terminals 41 for the MR element 1,
Reference numeral 42 is formed on the rigid substrates 70 and 40. These substrates 70 and 40 can be used as connectors to be inserted into a measuring device (not shown) at the time of characteristic measurement.

The switch means 3 is composed of NTC thermistor elements 311 and 312. The NTC thermistor elements 311 and 312 are connected in series between each of the lead conductors 21 and 22 and terminals 41 and 42 provided on the substrate 40. In the embodiment, two NTC thermistors 311 and 312 are shown, but may be one or two or more.

The switching means 3 is replaced by the NTC thermistor element 3
11, 312, and the drive timing,
The function and effect thereof are as already described with reference to FIG. 4. A simple operation of supplying heat energy to the NTC thermistor elements 311 and 312 from the outside or stopping the supply is only a simple operation. Thus, the configuration and release of the electrostatic breakdown prevention function can be executed.

FIG. 29 is a plan view showing still another embodiment of the magnetic head device according to the present invention, and FIG. 30 is an electric circuit diagram of the magnetic head device shown in FIG. The embodiment shown in FIGS. 29 and 30 shows a magnetic head device to which the thin film device shown in FIG. 5 is applied. A substrate 30 is mounted on the side of the head support device 6, and a PTC thermistor element 31 constituting the switch means 3 for preventing electrostatic breakdown on the substrate 30.
And a PTC thermistor element 32 for heating.
On the substrate 30, terminals 71 and 72 for the recording element 52 (see FIG. 30), terminals 41 and 42 for the MR element 1, and terminals 43 and 4 for the PTC thermistor element 32 for heating.
4 are provided.

The switch means 3 is composed of NTC thermistor elements 311 and 312. The NTC thermistor elements 311 and 312 are mounted on a substrate 30, and are connected in series between each of the lead conductors 21 and 22 and terminals 41 and 42 provided on the substrate 30.

On the substrate 30, a heating PTC thermistor element 32 is further provided. The heating PTC thermistor 32 is provided on the substrate 30 by the NTC thermistor element 3.
11 and 312. The heating PTC thermistor 32 is connected to terminals 43 and 44 provided on the substrate 30.

The switching means 3 is replaced by the NTC thermistor element 3
11, 312, and the drive timing,
The operation and effect are as described with reference to FIG. 5. Heat energy is supplied to the NTC thermistor elements 311 and 312 from the heating PTC thermistor element 32 or the supply of heat energy is stopped. The configuration and release of the electrostatic breakdown prevention function can be executed with only a simple operation.

FIG. 31 is a plan view showing still another embodiment of the magnetic head device according to the present invention, and FIG. 32 is an electric circuit diagram of the magnetic head device shown in FIG. The embodiment shown in FIGS. 31 and 32 shows a magnetic head device to which the thin film device shown in FIG. 6 is applied. Terminals 71 and 72 for the recording element 52 (see FIG. 32) and terminal 4 for the MR element 1
1 and 42 are formed on rigid substrates 70 and 40.
These substrates 70 and 40 can be used as connectors to be inserted into a measuring device when measuring characteristics.

The switching means 3 includes NTC thermistor elements 311, 312 and a PTC thermistor 313. The NTC thermistor elements 311 and 312 are connected in series between each of the lead conductors 21 and 22 and terminals 41 and 42 provided on the substrate 40. PTC
The thermistor element 313 is connected to the terminal 4 formed on the substrate 40.
1, 42. The heating PTC thermistor element 32 is thermally coupled to the PTC thermistor element 313.

The NTC thermistor elements 311 and 312 and the PTC thermistor element 313 constituting the switch means 3
The drive timing and the operation and effect thereof are as described with reference to FIG. Immediately before or after incorporation into the magnetic recording / reproducing device, the substrate 4
0 along the cutting line XX, and the PTC thermistor element 31
3 is separated from the substrate 40.

FIG. 33 is a plan view showing still another embodiment of the magnetic head device according to the present invention, and FIG. 34 is an electric circuit diagram of the magnetic head device shown in FIG. The embodiment shown in FIGS. 33 and 34 shows a magnetic head device to which the thin film device of FIG. 12 is applied. The signal processing circuit 20 includes the head support device 6
It is mounted on. The signal processing circuit 20 is a read / write circuit, and includes the MR element 1 and the recording element 52 (see FIG. 34).
It is connected to the. The switch means 3 comprises a PTC thermistor element 31 and is thermally coupled to the signal processing circuit 20 on the head support device 6.

The signal processing circuit 20 generates heat at a considerable temperature during signal processing. The PTC thermistor element 31 performs a switching operation by thermal energy generated when the signal processing circuit 20 operates.

A substrate 30 is attached to the side of the head support device 6, and the recording element 52 is placed on the substrate 30.
(See FIG. 34), terminals 41 and 42 for the MR element 1 and terminals 43 and 44 for the PTC thermistor element 32 for heating are provided. PTC
The thermistor element 31 is connected to terminals 41 and 42.

The drive timing of the PTC thermistor element 31 constituting the switch means 3 and the operation and effect thereof have already been described with reference to FIG.

FIG. 35 is an electric circuit diagram of still another embodiment of the magnetic head device according to the present invention. This embodiment shows an example suitable for a case where the switch means 3 is configured using a semiconductor switch element, a phototransistor, or the like (see FIGS. 7 to 11).

The phototransistors 311 and 312 and the light emitting element 33 constituting the switch means 3 constitute an integrated circuit 200 together with the signal processing circuit 20.

FIG. 36 is a plan view of a magnetic head device in which the integrated circuit 200 of FIG. 35 is mounted on the head support device 6. A substrate 30 is attached to a side portion of the head support device 6, and terminals 71, 72 and 41 to 4
4 are provided.

FIG. 37 is a view showing a magnetic recording / reproducing apparatus according to the present invention. The magnetic recording / reproducing apparatus according to the present invention includes a positioning device 10, a magnetic disk 9, and a well-known head support device 6.
And a thin-film magnetic head 5 according to the present invention. The magnetic disk 9 is moved by an arrow a by a rotation driving mechanism (not shown).
Is rotated in the direction of. The positioning device 10 is of a rotary actuator type and supports one end of the head support device 6 and is driven at a predetermined angle (skew angle) on the surface of the magnetic disk 9 in the direction of the arrow b1 or b2. As a result, writing to the magnetic disk 9 and reading from the magnetic disk 9 are performed on a predetermined track.

[0117]

As described above, according to the present invention, the following effects can be obtained. (A) It is possible to provide a thin film device, a thin film magnetic head device, and a magnetic recording / reproducing device that can easily perform the configuration and release of the electrostatic breakdown prevention function. (B) It is possible to provide a thin film device, a thin film magnetic head device, and a magnetic recording / reproducing device that can easily provide an electrostatic breakdown preventing function to a thin film element.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing a configuration of a thin film device according to the present invention.

FIG. 2 is a view showing a specific embodiment of the thin film device according to the present invention.

FIG. 3 is a view showing still another embodiment of the thin film device according to the present invention.

FIG. 4 is a view showing still another embodiment of the thin film device according to the present invention.

FIG. 5 is a view showing still another embodiment of the thin film device according to the present invention.

FIG. 6 is a view showing still another embodiment of the thin film device according to the present invention.

FIG. 7 is a view showing still another embodiment of the thin film device according to the present invention.

FIG. 8 is a view showing still another embodiment of the thin film device according to the present invention.

FIG. 9 is a view showing still another embodiment of the thin film device according to the present invention.

FIG. 10 is a view showing still another embodiment of the thin film device according to the present invention.

FIG. 11 is a view showing still another embodiment of the thin film device according to the present invention.

FIG. 12 is a view showing still another embodiment of the thin film device according to the present invention.

FIG. 13 is a view showing still another embodiment of the thin film device according to the present invention.

FIG. 14 is a plan view of a magnetic head device according to the present invention.

FIG. 15 is an enlarged front view of a magnetic head attachment portion of the magnetic head device shown in FIG.

16 is an enlarged bottom view of a magnetic head mounting portion of the magnetic head device shown in FIG.

FIG. 17 is an enlarged cross-sectional view showing a thin-film element portion of the thin-film magnetic head.

FIG. 18 is an enlarged sectional view showing a more detailed structure of an MR element included in the thin-film magnetic head.

19 is an electrical connection diagram of the magnetic head device shown in FIGS. 14 to 18. FIG.

FIG. 20 is a plan view showing another embodiment of the magnetic head device according to the present invention.

21 is an electric circuit diagram of the magnetic head device shown in FIG.

FIG. 22 is a plan view showing still another embodiment of the magnetic head device according to the present invention.

FIG. 23 is a plan view showing another embodiment of the magnetic head device according to the present invention.

24 is an electric circuit diagram of the magnetic head device shown in FIG.

FIG. 25 is a plan view showing another embodiment of the magnetic head device according to the present invention.

26 is an electric circuit diagram of the magnetic head device shown in FIG.

FIG. 27 is a plan view showing another embodiment of the magnetic head device according to the present invention.

28 is an electric circuit diagram of the magnetic head device shown in FIG. 27.

FIG. 29 is a plan view showing still another embodiment of the magnetic head device according to the present invention.

30 is an electric circuit diagram of the magnetic head device shown in FIG.

FIG. 31 is a plan view showing still another embodiment of the magnetic head device according to the present invention.

32 is an electric circuit diagram of the magnetic head device shown in FIG.

FIG. 33 is a plan view showing still another embodiment of the magnetic head device according to the present invention.

34 is an electric circuit diagram of the magnetic head device shown in FIG.

FIG. 35 is an electric circuit diagram of still another embodiment of the magnetic head device according to the present invention.

36 is a plan view of a magnetic head device in which the integrated circuit shown in FIG. 35 is mounted on a head supporting device.

FIG. 37 is a diagram showing a magnetic recording / reproducing apparatus according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Thin film element 21, 22 Lead conductor 3 Switching means

Claims (23)

[Claims] 1. A thin film device comprising a thin film element, at least two lead conductors, and switch means, wherein the lead conductor is connected to the thin film element, and wherein the switch means is connected to the lead conductor. The thin film element is connected and performs a switching operation by energy given from the outside to prevent electrostatic breakdown of the thin film element. 2. The apparatus according to claim 1, wherein said switch means includes a thermistor element. 3. The apparatus according to claim 2, wherein said switch means includes a thermistor element having a positive temperature coefficient of resistance. 4. The device according to claim 3, wherein the thermistor element is connected between the lead conductors. 5. The apparatus according to claim 2, wherein said switch means includes a thermistor element having a negative temperature coefficient of resistance. 6. The device according to claim 5, wherein the thermistor element is connected in series to the lead conductor. 7. The device according to claim 1, wherein the externally applied energy is thermal energy. 8. The apparatus according to claim 7, further comprising a heating element, said heating element providing said thermal energy to said switch means. 9. The apparatus according to claim 8, wherein the heating element includes a thermistor having a positive temperature coefficient of resistance. 10. The apparatus according to claim 1, wherein said switch means includes a semiconductor switch. 11. The device according to claim 10, wherein said semiconductor switch includes a phototransistor. 12. The device according to claim 10, wherein the semiconductor switch includes a combination of a phototransistor and a light emitting element. 13. The device according to claim 10, wherein the semiconductor switch includes a three-terminal switch element. 14. The apparatus according to claim 10, wherein said switch means comprises a mechanical switch means. 15. The apparatus according to claim 1, further comprising a signal processing circuit, wherein the signal processing circuit is connected to the thin film element, and wherein the switch means , Provided at a subsequent stage of the signal processing circuit. 16. The device according to claim 15, wherein said switch means performs a switching operation by thermal energy generated when said signal processing circuit operates. 17. The device according to claim 1, further comprising a slider, wherein the thin-film element is a magnetic transducer, and is mounted on the slider. The slider and the thin-film element constitute a thin-film magnetic head. 18. The apparatus according to claim 17, further comprising a head support device, wherein said head support device supports said thin-film magnetic head. 19. The device according to claim 17, wherein the thin film element includes a magnetoresistive film. 20. The device according to claim 19, wherein the magnetoresistive film has a multilayer structure. 21. The device according to claim 20, wherein the magnetoresistive film has a spin valve film structure. 22. The apparatus according to claim 17, further comprising a writing thin film element, wherein said writing element is mounted on said slider. 23. A magnetic recording / reproducing device including a magnetic disk and a magnetic head device, wherein the magnetic disk is driven to rotate, and the magnetic head device is described in any one of claims 16 to 21. And performs recording and reproduction with the magnetic disk.