Teijin Limited

Other

Pioneer Electronic Corporation

Konishiroku Photo Industry Co., Ltd.

Nkk Corporation

Masahiko Naoe

Sadao Kadokura

Takashi Tomie

Kazuhiko Honjo

Shozo Ishibashi

Tsunehiro Tsukagoshi

Hiroyoshi Suenaga

Kuninori Minakawa

Hideaki Fukai

Hiroshi Ito

Toyoaki Hirata

Shinichiro Otaka

A mirrortron sputtering apparatus for sputtering on a substrate includes a vacuum chamber for placing therein a pair of targets spaced apart from each other with inner surfaces thereof facing each other and outer surfaces thereof positioned opposite to the inner surfaces, and magnets respectively disposed closer to the outer surfaces of the targets for forming a magnetic field between said pair of targets. The magnetic field has a magnetic field distribution with a peripheral region having a high magnetic flux density and a center region having a low magnetic flux density. In this arrangement, the substrate is set alongside a space between the pair of targets as facing said magnetic field.

Mirrortron sputtering apparatus

A magnetic disk substrate having a composition wherein (V/13)+(Fe/20)+(Cr/17)+(Ni/31)+(Co/23) are no greater than 0.010%, Rem+Si+B+W are no greater than 0.015% (where Rem denotes rare earth metals), 0+2N+0.75C are no less than 0.03% and no greater than 0.5%, and the remainder consists substantially of Ti, all % being weight %.

Magnetic disk substrate

A photomagnetic memory medium of an amorphous thin film of a rare-earth transition metal alloy of non-columnar structure deposited on a substrate. In order to achieve the non-columnar structure, the alloy is sputtered in the presence of a plasma but the plasma is confined by a magnetic field so as not to touch the substrate. The alloy is preferably TbFeCo.

Photomagnetic memory medium having a non-columnar structure

A magnetic recording medium conventionally utilizes the in-plane magnetization mode, but recently the perpendicular magnetization mode utilizing the perpendicular anisotropy of an hcp cobalt alloy layer, in which the C axis is oriented perpendicular to the layer surface, has been proposed. The known perpendicular magnetic recording medium is produced by means of RF sputtering and comprises a Permalloy layer, as layer of a low coercive-force material, between the nonmagnetic base and the hcp cobalt alloy layer. The perpendicular anisotropy attained by the present invention in very excellent and is superior to that of a perpendicular recording medium having no Permalloy layer because a Co-Ta alloy is used as the layer of a low coercive-force material.

Perpendicular magnetic recording medium, method for producing the same,

There is provided a method of ion beam generation wherein a plurality of opposing targets are sputtered by plasma generated in a space confined by these targets and ionized particles thereby generated are led outside of the above space in a given direction under presence of an electric field. In connection to this method, an ion beam generator is disclosed comprising a plurality of targets, a plasma generating means to generate plasma necessary to sputter these targets in a space confined by these targets and a control electrode to lead ionized particles generated by sputtering with the above plasma outside of such space under control of their energy.

Method of ion beam generation and an apparatus based on such method

A magnetic recording medium conventionally utilizes the in-plane magnetization mode, but recently the perpendicular magnetization mode utilizing the perpendicular anisotropy of an hcp cobalt alloy layer, in which the C axis is oriented perpendicular to the layer surface, has been proposed. The known perpendicular magnetic recording medium is produced by means of RF sputtering and comprises a Permalloy layer, as layer of a low coercive-force material, between the nonmagnetic base and the hcp cobalt alloy layer. The perpendicular anisotropy attained by the present invention is very excellent and is superior to that of a perpendicular recording medium having no Permalloy layer because a Co-Ta alloy is used as the layer of a low coercive-force material.

Perpendicular magnetic recording medium method for producing the same,

Magnetic recording medium conventionally utilizes the in-plane magnetization mode, but, recently, the perpendicular magnetization mode utilizing the perpendicular anisotropy of an hcp cobalt alloy layer, in which C axis is oriented normal to the layer surface, is proposed. The known perpendicular magnetic recording medium has been produced by an RF sputtering, but such medium is of too low flexibility to use it in the form of a magnetic tape. In addition, the production rate of the perpendicular magnetic recording medium by RF sputtering is very low. The perpendicular magnetic recording medium is very flexible due to particle pattern (FIGS. 10, 12 and 13) completely distinct from the conventional columnar pattern (FIGS. 8 and 11). In addition, the production rate is high, because the base (20) is located beside a space between the targets (T.sub.1, T.sub.2) of a sputtering device and further the magnetic field is generated perpendicularly to the sputtering surfaces (T.sub.1s, T.sub.2s) by a field coil (32) or magnets (32, 33). The present invention makes it possible to commercially produce the perpendicular magnetic recording medium, especially in the tape form.

Perpendicular magnetic recording medium

Magnetic recording medium conventionally utilizes the in-plane magnetization mode, but, recently, the perpendicular magnetization mode utilizing the perpendicular anistropy of an hcp cobalt alloy layer, in which C axis is oriented normal to the layer surface, is proposed. The known perpendicular magnetic recording medium has been produced by an RF sputtering, but such medium is of too low flexibility to use it in the form of a magnetic tape. In addition, the production rate of the perpendicular magnetic recording medium by RF sputtering is very low. The perpendicular magnetic recording medium is very flexible due to particle pattern (FIGS. 10, 12 and 13) completely distinct from the conventional columnar pattern (FIGS. 8 and 11). In addition, the production rate is high, because the base (20) is located beside a space between the targets (T.sub.1, T.sub.2) of a sputtering device and further the magnetic field is generated perpendicularly to the sputtering surfaces (T.sub.1s, T.sub.2s) by a field coil (31) or magnets (32, 33). The present invention makes it possible to commercially produce the perpendicular magnetic recording medium, especially in the tape form.

Growing community of inventors

Tokyo, Japan

Masahiko Naoe