DE2148898A1 - LAYERED MAGNETIC CORE FOR WRITING, READING AND / OR ERASING HEADS IN MAGNETIC LAYERED STORAGE DEVICES FOR PARTICULARLY HIGH WRITING DENSITY AND METHOD FOR ITS MANUFACTURING - Google Patents

Description

Layered magnetic core for write, read and / or
Erase heads in magnetic layer storage devices for particularly high writing density and a process for its manufacture

Pie invention relates to a layered magnetic core for write, read and / or erase heads in magnetic layer storage devices for particularly high writing density.

It is known per se to manufacture the magnetic cores for write, read and / or erase heads in magnetic layer storage devices from thin magnetic sheets which are layered together to form a magnetic core and are thereby isolated from one another. This process of the known magnetic cores for internal heads finds its practical limit in the very thin magnetic material from which the individual layers of the magnetic core have to be made. At the moment, for example, i'iagnet! Material foils with a thickness of ~> 20 yuin are available. With the total thicknesses of the magnetic cores of * <^ 100 µm required in the future, only about four layers would be possible with such a magnetic material film thickness of '.> 20 µm. However, this subdivision is much too coarse in view of the desired good properties of the magnetic heads. About ten times the number of layers is desired for the desired high write density in modern magnetic layer storage devices.

It is also already known to manufacture the magnetic cores for write, read and / or erase heads from ferrite material. Cores of this type are, however, due to the grain sizes of the ferrite

VPA 9/210/1066 Kar / Hlg

3098 U / 1024

BATH ORIGINAL

material and its mechanical sensitivity No longer applicable for the above-mentioned orders of magnitude of core thicknesses <100 yum.

The invention was therefore based on the object of looking for a layered magnetic core for write, read and / or erase heads in magnetic layer storage devices for particularly high write density, which has very good magnetic properties with high strength and which also works well with the smallest dimensions leaves. This is achieved provided by ira Aufdarnpfverfahre ^ W Hagnetmaterialschichten manufacturing of some / um thickness According to the invention, alternating with insulating layers also prepared in Aufdampdverfahren of a few tenths / on the thickness. The magnetic material layers preferably consist of magnetic soft iron or mu-meta 11 and the insulating layers preferably consist of silicon oxide or silicon nitrite.

In order to produce the magnetic heads according to the invention, it is further proposed to alternate layers of magnetic material and insulating layers with a thickness ratio of about 10: 1 for a plurality of magnetic cores on a detachable one To evaporate pad and then the layered Remove the magnetic material disc from the detachable pad. With regard to the smallness of the individual magnetic core parts it is particularly advantageous to remove the individual parts of the magnetic cores from the magnetic material disc using a so-called wire EDM machine to separate from each other.

The attached drawing shows in Figure 1 the rough shape of a magnetic core according to the invention for a writing, Read and / or erase head on a scale of 1: 1,

2 shows the same magnetic core on a scale of 10: 1 for a better overview.

VPA 9/210/1066 _Ä _ 3 _

-309814/1024

Figure 3 shows on a scale of 2000: 1 the products that have been steamed up Magnetic material layers of a few µm thick, which are also produced using the vapor deposition process Alternate layers of insulation a few tenths of a thickness.

Finally, Figure 4 shows one according to the invention Magnetic material disk made of alternately vapor-deposited magnetic material layers and Insulating layers.

As indicated by the subdivision of the magnetic material disk, a multiplicity of magnetic cores can be made therefrom according to FIG of the invention can be cut out, for example, with a so-called wire EDM machine.

5 claims
4 figures

VPA 9/210/1066 _

309814/1024

Claims (5)

- 4 claims ' (J / Layered magnetic core for write, read and / or Erase heads in magnetic layer storage devices for particularly high write density, characterized by Magnetic material layers produced in the vapor deposition process with a thickness of a few .mu.m, which are also produced in the vapor deposition process Alternate insulating layers of a few tenths / um thickness. 2. Magnetic core according to claim 1, characterized in that that the Ifegnettnaterialschichten of magnetic Soft iron or Mu-Meta11 exist. 3. Magnetic core according to claims 1 or 2, characterized characterized in that the insulating layers consist of silicon oxide or silicon nitride. 4. A method for manufacturing magnetic heads according to a of claims 1 to 3, characterized in that that on a detachable base alternating layers of magnetic material and insulating layers with a thickness ratio of about 10: 1 for a variety of magnetic heads and then the layered magnetic material disc is removed from the releasable pad. 5. The method according to claim 4, characterized in that that the individual parts of the magnetic cores from the magnetic material disc with the help of a so-called wire EDM machine separated from each other. VPA 9/210/1066 30981A / 1024