JPS63175202A - magnetic memory package - Google Patents

Abstract

PURPOSE:To improve the S/N in a high density magnetic recording system by using a thermoelectric cooling element to cool a thin film magnetic head element and an amplifier circuit. CONSTITUTION:A thin film magnetic head amplifier circuit serving as a 1st thermoelectric cooling element and a thermoelectric cooling integrated element 3 are moved by drive mechanisms 8a and 8b and set at a prescribed track position respectively. When the DC currents are supplied to current terminals 6a and 6b respectively, a 2nd thermoelectric cooling element 5 works by the Peltier effect to cool a thermal conductor 4 and the element 3 having a contact with the conductor 4. The thermal conduction efficiency is improved by applying the vacuum grease, etc., on the contact surface between the conductor 4 and the element 3. Furthermore the currents are supplied to a p-type semiconductor 22 and an n-type semiconductor 23 which are connected series with each other. Thus a two-tier thermoelectric cooling element is obtained by the Peltier effect in the same way to improve the cooling effect. At the same time, the vacuum atmosphere is secured for a thin film magnetic head element 17 and on the magnetic disk side face of the circuit 18. In such a way, the cooling effect is further improved and a high S/N is secured for a high density magnetic recording system.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic memory, and particularly to a magnetic head device, a magnetic recording medium, and a sealed magnetic memory package with a built-in drive mechanism suitable for high-density magnetic recording.

[Conventional technology]

The challenges in realizing high-density magnetic recording to increase the storage capacity per unit magnetic recording medium are ensuring a high S/N ratio and reducing spacing loss of the head-medium contact.

In order to ensure a high S/N ratio, which is the first issue, it is first necessary to increase the output of the magnetic head. One possible means of increasing output is to reduce the length of the magnetic core (hereinafter referred to as magnetic path length) that forms the magnetic circuit of the magnetic core, and for this purpose, the so-called thin film that forms the magnetic core, coil, etc. A magnetic head is effective. However, as the magnetic path length of a thin-film magnetic head is made smaller, the coil becomes finer and the cross-sectional area of the coil decreases, resulting in an increase in coil resistance, which results in an increase in head impedance noise, resulting in a higher S/N ratio than expected. A problem arises in that it is no longer possible to secure the In addition, in high-density magnetic recording, a cylindrical frequency band is used, and both the track width and the recording wavelength are small, so the recording signal level from the recording medium becomes small, and the noise is caused by the head impedance noise mentioned above and the thermal noise of the reproduction amplifier. becomes dominant. In order to ensure a high S/N ratio, the key is how to suppress the above noise. As a means of suppressing noise, it is conceivable to use a thermoelectric cooling element to cool the magnetic head and amplifier circuit, but no similar proposal has been found at present.

The second issue is spacing and reducing the loss of one person.

Conventional magnetic head, magnetic disk contact shape! There are two types of imaginary. One of them is a Winchester type floating magnetic head. This kind of magnetic head is
Since spacing is obtained by using the air flow formed between the magnetic head and the magnetic disk, it is difficult in principle to reduce the spacing loss. The other method is a method in which a magnetic disk or floppy magnetic disk is brought into direct contact with a magnetic head, as described in Japanese Patent Application Laid-Open No. 60-202579. However, this kind of method
As the relative speed of the head medium increases, the coefficient of friction increases and the wear of the magnetic head or magnetic disk progresses.Although it is possible to reduce the loss of one member of the spacing, there is a problem that stable contact and long life cannot be obtained. There is.

Examples of thermoelectric cooling elements having a structure similar to the above-mentioned thermoelectric cooling elements include those described in Japanese Patent Application Laid-Open No. 58-6186, Japanese Patent Application Laid-Open No. 58-7888, and Japanese Patent Application Laid-Open No. 56-126988.

[Problem that the invention seeks to solve]

In the above conventional technology, consideration has been given to reducing the head impedance noise of the thin-film magnetic head and the thermal noise of the reproducing amplifier, which are issues in realizing high-density magnetic recording, and to realizing the spacing loss with stable contact. However, there was a problem that high-density magnetic recording was difficult.

SUMMARY OF THE INVENTION An object of the present invention is to provide a magnetic memory package that solves the above problems, ensures a high S/N ratio, and reduces spacing loss.

[Means for solving problems]

The above purpose is to cool the thin film magnetic head and the reproduction amplifier circuit using a thermoelectric cooling element to ensure a high S/N ratio, and to make the head-magnetic recording medium contact in a vacuum or in a trace amount of inert gas atmosphere using a direct contact method. This is achieved by taking .

[Effect]

When a current is passed through a junction of two different materials, one side of the junction generates heat and the other side absorbs heat (Bertier effect).

Thermoelectric cooling elements that utilize this Beltier effect are known. In the present invention, a thin film magnetic head and a reproducing circuit are formed on the heat absorption surface of a thermoelectric cooling element, and a current is passed through the thermoelectric cooling element to cool the thin film magnetic head and reduce coil resistance. As a result, the magnetic path length of the head can be significantly reduced, the head output can be increased, and the total thermal noise including the cooled reproduction circuit can be reduced, thereby achieving a high S/N ratio.

In addition, by housing the thin-film magnetic head and magnetic recording medium in a sealed case with a vacuum or a trace amount of inert gas atmosphere, oxygen in the atmosphere, which was a cause of increased friction coefficient and wear, was removed.

Since shadow particles such as moisture can be removed, stable direct contact can be achieved and spacing loss can be reduced.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of a magnetic memory package according to the present invention, in which 1a and 1b are sealed cases;
Case 1a has a double structure to provide insulation effect.
, lb 2a is a vacuum space. Inside the case 2b is vacuum,
Or argon.

In an atmosphere of a trace amount of inert gas such as neon, 3 is the first thermoelectric cooling element, which is a thin film head/amplifier circuit/thermoelectric cooling integrated element, 4 is the thermal conductor, and 5 is the second thermoelectric cooling element. Elements, 6a and 6b are current extraction terminals, 7 is a magnetic disk as a recording medium, and 8a.

8b is a drive mechanism for track feeding of the thin film magnetic head element 3; 9 is a pad for realizing good contact pressure between the thin film magnetic head element of the integrated element 3 and the magnetic disk 7;
10 is a support stand for supporting the rotation of the magnetic disk 7;
Reference numerals 11 and 12 denote drive units equipped with magnets for transmitting the driving force of the motor 13 for rotating the magnetic disk 7 in a non-contact manner.

FIG. 2 is a sectional view showing an example of the structure of the integrated thin film magnetic head/amplifier circuit/thermoelectric cooling element shown in FIG.
1 is a thin film magnetic head element, 14 is a magnetic core, 15 is a magnetic gap, 16 is a coil, and 18 is a thin film magnetic head element 1.
7, a recording and reproducing amplifier circuit; 19a is a heat conductor on the heat absorption side and 19b is a heat conductor on the heat generation side; 20a and 20b are electrical insulators and materials with good thermal conductivity; 22 is a p constituting a thermoelectric cooling element; type semiconductor, 23 is also an n-type semiconductor, 2
1a and 21b are current connections of the semiconductor, and 24 is an electrical and thermal insulator.

Next, the operation of an embodiment of the present invention configured as described above will be explained. (The 511 disk 7 is driven by the drive rotary motor 1.
The driving force of No. 3 is transmitted by the magnet-equipped drive mechanism 11.12 to rotate at high speed in a vacuum atmosphere or the like inside the case 2b. The integrated thin film magnetic head/amplifier circuit/thermoelectric cooling element 3, which is the first thermoelectric cooling element, is moved by drive mechanisms 8a and 8b so that it is placed at a predetermined track position. current terminal 6a,
When direct current is passed through 6b, the second thermoelectric cooling element 5 works due to the Peltier effect, and the thermal conductor 4 and the integrated element 3 in contact with it are cooled. At this time, if vacuum grease or the like is provided on the contact surface between the heat conductor 4 and the integrated element 3, the heat conduction will be further improved. Furthermore, as shown in FIG. 2, a p-type semiconductor 22 and an n-type semiconductor 23 are connected in series.
If a current is passed through, a two-stage thermoelectric cooling element will be formed due to the Peltier effect, and the cooling effect will increase. Further, the side surfaces of the magnetic disk (lower surface in FIG. 2) of the thin-film magnetic head element 17 and amplifier circuit 18 to be cooled are in the vacuum atmosphere, etc., and a heat insulation effect can be expected, so that the cooling effect is further increased. With this configuration, minus 100°
Temperatures below C can be achieved. In this way, the coil 16 of the thin-film magnetic head element 17 and the amplifier circuit 18 can be efficiently cooled, and by reducing each resistance value, the head impedance, which was a technical issue in realizing high-density magnetic recording, can be improved. Noise and amplifier noise can be significantly reduced, and a good S/N ratio can be achieved.The above noise N is expressed by the following formula.

N=■] G lower Kl: Boltzmann constant R: Sum of head coil resistance and amplifier equivalent noise resistance T: Element, element temperature B: Frequency band Compared to room temperature, coil resistance R is half, temperature T is 2
/3, the noise N can be reduced by about 5 dB compared to room temperature.

Furthermore, as in this embodiment, FWJ! Due to the contact between the magnetic head element 17 and the magnetic disk 7, it is possible to eliminate the effects of oxygen, moisture, etc., which are expected to cause dew condensation, an increase in the coefficient of friction, and an increase in sliding wear when the thin-film magnetic head element 7 is cooled. Therefore, stable direct contact can be achieved and spacing loss can be reduced.

FIG. 3 is a recording/reproduction characteristic diagram in an embodiment of the present invention.
When recording and reproducing using a perpendicular recording medium with a track width of 5 μm and a recording wavelength of 0.3 μm, the spacing loss can be reduced by approximately 5 dB by improving the spacing amount by 0.03 μm compared to the conventional configuration. Including the amount of noise reduction due to cooling, the total S/N is 1 odB.
The ratio can be improved.

4(a) and (bl are front and side views showing other configuration examples of the integrated thin film magnetic head/amplifier circuit/thermoelectric cooling element shown in FIG. 1; the same reference numerals as in FIG. 2 are the same). 25 is a common substrate.

In the configuration example shown in the figure, the p-type semiconductor 22 and n-type semiconductor 23 that constitute the thin-film magnetic head element 17, the amplifier circuit 18, and the thermoelectric cooling element are formed on the common substrate 25 by a thin-film formation process, which facilitates mass production. It has an excellent structure. The above is carried out even with this kind of configuration.

The same effect as the example can be obtained.

Further, in the embodiment described above, the package has a double structure with the sealed cases la and lb, but it is not necessarily necessary to have a double structure when the atmosphere inside the case 2b is vacuum.

〔Effect of the invention〕

As explained above, according to the present invention, head impedance noise and amplifier noise can be reduced by cooling the thin film magnetic head element and the amplifier circuit using a thermoelectric cooling element, and the head impedance noise and amplifier noise can be reduced. By using the °ζ direct contact method in a vacuum or a trace amount of inert gas atmosphere, it is possible to stably reduce spacing loss, and the S/N in high-density memory 1. machining is improved.
The ratio can be improved by about 10d13 compared to the conventional one.

This results in large amounts of memory for computers or
By allocating high-density magnetic recording to miniaturization, it becomes possible to apply it as an ultra-small memory package for playback.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a magnetic memory package according to the present invention;
2 is a sectional view showing an example of the structure of the integrated thin film magnetic head/amplifier circuit/thermoelectric cooling element shown in FIG. ,
(b) is a sectional view of the integrated thin film magnetic head, amplifier circuit, and thermoelectric cooling element shown in FIG. FIG. la, lb--... Sealed case, 3-...- Thin film magnetic head amplifier circuit which is the first thermal lightning cooling element.
Thermoelectric cooling integrated element, 4---thermal conductor, 5--
...Second thermoelectric cooling element, 7--Magnetic disk, 9--Pad, 10--1--Support, 13--Motor , 14-...-magnetic core, 15---1111 magnetic gap, 16-...
・Coil, 17...-Thin film head element, 18--
----- Recording/playback amplifier circuit, 19 a, 19
b ・----1 Heat transfer exclusive, 20 a, 20 b-
-----1 electrical insulator, 22---- P type semiconductor,
23--- n-type semiconductor, 25--- common substrate. Fig. 1 1o, Ib: Sealed case 7: Stone air - Task 2a, 2b: Empty air 8a, 8
b:'t-ra, Mtf1M3 for ri1ri: vine M嘱1
Nshi Kei 1) lζ ko-9 Nino (-sito 4; wealth conductor
IO-Support stand 5: '1i2tn thermoelectric arc'rl 1,12:aB
7. xtyAg 1113: Motor! ii1'2 Figure I5: 23: N-type semiconductor 16: Coil 24: I7: 4 films a! Hetsu) 'Element-7- 18: Amplifier circuit

Claims (1)

[Claims] 1. A magnetic memory package consisting of a magnetic recording medium, a drive mechanism for driving the magnetic recording medium, a magnetic head device, and a sealed case housing these, wherein the magnetic head device includes a thin-film magnetic head and a reproduction amplifier circuit. A magnetic memory package comprising an integrated element including a thermoelectric cooling element and configured to reduce head impedance noise of a thin film magnetic head and thermal noise of a reproducing amplifier circuit.