公开(公告)号：JPH0676279A

公开(公告)日：1994-03-18

申请号：JP15024793

申请日：1993-06-22

Applicant: IBM

Inventor： MEARII EFU DERUNAA ,  TADASHI YOGI ,  ANSONII UU ,  DAN ESU PAAKAA

IPC: C23C14/06 ,  C23F4/00 ,  G11B5/64 ,  G11B5/65 ,  G11B5/72 ,  G11B5/73 ,  G11B5/738 ,  G11B5/82 ,  G11B5/84 ,  G11B5/851 ,  G11B25/04 ,  G11B33/14

Abstract: PURPOSE: To obtain a metal alloy magnetic recording disk for contact recording by successively forming a nickel oxide film, a lower layer and a magnetic layer containing a cobalt alloy on a aluminum alloy substrate having a nickel- phosphorus surface coating. CONSTITUTION: A Ni-P coating film 62 after superfinishing process having no roughness on an aluminum alloy substrate 61 is oxidized to form a NiO coating film 64. By forming the NiO film 64, magnetic layers 66, 67 containing cobalt alloy to be formed by sputtering have extremely high saturation coercive force, and thereby, the obtd. disk can be used for a contact recording system. The layers which constitute the disk conform to the surface of the polished NiP, and therefore, the upper layer of the disk for a contact recording type disk file has an extremely smooth surface.

公开(公告)号：JPH09190945A

公开(公告)日：1997-07-22

申请号：JP28401896

申请日：1996-10-25

Applicant: IBM

Inventor： JIEEMUZU KENTO HAWAADO ,  RANDAARU JIYOOJI SHIMONZU ,  TADASHI YOGI

IPC: C23C14/14 ,  G11B5/64 ,  G11B5/65 ,  G11B5/66 ,  G11B5/73 ,  G11B5/738 ,  G11B5/85 ,  G11B5/851 ,  H01F10/16 ,  H01F41/18

Abstract: PROBLEM TO BE SOLVED: To reduce intrinsic noise of a recording medium. SOLUTION: In the case of an improved CoPt alloy magnetic recording disk for horizontal recording, the magnetic recording layer in the disk contains oxygen more than 5 atomic percent but less than 30 atomic percent. The disk is formed by taking oxygen in argon when sputtering for CoPt alloy magnetic layer. The disk construction obtained has considerably less noise of intrinsic medium even though the recording line density is high under the same conditions compared to that of a disk construction formed without taking in oxygen during sputtering for CoPt alloy magnetic layer. S/N ratio can be further improved by giving a head treatment to the disk after the sputtering process.

公开(公告)号：JPH0676261A

公开(公告)日：1994-03-18

申请号：JP15395893

申请日：1993-06-24

Applicant: IBM

Inventor： MARII FURANSHISU DOUANAA ,  TADASHI YOGI ,  ANSONII WAI UU ,  DAN SUTEIIBUN PAAKAA

IPC: G11B5/02 ,  G11B5/64 ,  G11B5/66 ,  G11B5/72 ,  G11B5/73 ,  G11B5/738 ,  G11B5/82 ,  G11B5/84 ,  G11B5/851 ,  G11B25/04 ,  G11B33/14

Abstract: PURPOSE: To obtain a magnetic recording disk having an extremely smooth top face and high coercive force. CONSTITUTION: A NiP coating 62 as a super-finished coating on a disk substrate 60 is oxidized to form a NiO film 64. By forming the NiO film, the magnetic layer to be formed by sputtering vapor deposition in the succeeding process has high coercive force, and thereby, the disk can be used for a contact recording disk file. The NiO film and layers to be formed by vapor deposition have the same surfaces as the smooth surface of the polished NiP, and thereby, an extremely smooth surface of the disk top layer which is required for a head-disk interface of a contact recording disk file system can be maintained.

公开(公告)号：JPH0376018A

公开(公告)日：1991-04-02

申请号：JP20532390

申请日：1990-08-03

Applicant: IBM

Inventor： JIEEMUZU KENTO HAWAADO ,  RANDAARU JIYOOJI SHIMONZU ,  TADASHI YOGI

IPC: C23C14/14 ,  G11B5/64 ,  G11B5/65 ,  G11B5/66 ,  G11B5/73 ,  G11B5/738 ,  G11B5/85 ,  G11B5/851 ,  H01F10/16 ,  H01F41/18

Abstract: PURPOSE: To provide a CoPt alloy disk which decreases intrinsic medium noises even at a high recording line density by forming a magnetic layer of a compsn. contg. cobalt, platinum and oxygen and specifying the quantity of oxygen. CONSTITUTION: The magnetic recording layer in a disk contains oxygen of about 5atm.%, more preferably about 5 to 30atm.%. The disk is formed by introducing oxygen into argon during the adhesion of a CoPt alloy magnetic layer by sputtering. The resulted disk structure produces the considerably decreased intrinsic medium noises even at the high recording line density as compared with the disk structure formed under the similar conditions provided that the oxygen is not introduced into the argon during the adhesion of the CoPt alloy magnetic layer by sputtering. The disk is heat-treated after the adhering stage by sputtering, by which the S/N is further improved. The CoPt alloy disk having the decreased intrinsic medium noise even at the high recording line density is thus obtd.

公开(公告)号：MY107917A

公开(公告)日：1996-06-29

申请号：MYPI19931332

申请日：1993-07-07

Applicant: IBM

Inventor： MARY F DORNER ,  DAN S PARKER ,  ANTHONY WU ,  TADASHI YOGI

IPC: C23C14/06 ,  C23F4/00 ,  G11B5/64 ,  G11B5/65 ,  G11B5/72 ,  G11B5/73 ,  G11B5/738 ,  G11B5/82 ,  G11B5/84 ,  G11B5/851 ,  G11B25/04 ,  G11B33/14

Abstract: A MAGNETIC RECORDING DISK BASED ON CONVENTIONAL DISK TECHNOLOGY HAS BOTH AN EXTREMELY SMOOTH TOP SURFACE AND HIGH COERCIVITY, AND IS INCORPORATED IN A CONTACT RECORDING DISK FILE WHICH REQUIRES AN EXTREMELY SMOOTH HEAD-DISK INTERFACE AND A DISK WITH HIGH COERCIVITY. A SUPERFINISHED UNTEXTURED NIP COATING ON A DISK SUBSTRATE IS OXIDIZED TO FORM A NI0 FILM. THE NI0 FILM PERMITS THE SUBSEQUENTLY SPUTTER DEPOSITED MAGNETIC LAYER TO HAVE MUCH HIGHER COERCIVITY, WHICH ENABLES THE DISK TO BE USED IN CONTACT RECORDING APPLICATIONS. THE NI0 FILM AND THE LATER DEPOSITED LAYERS MAKING UP THE DISK, INCLUDING THE TOP PROTECTIVE OVERCOAT. CONFORM TO THE SMOOTH SURFACE OF THE POLISHED NIP, THUS PRESERVING THE EXTREMELY SMOOTH SURFACE OF THE TOP LAYER OF THE DISK, WHICH IS REQUIRED FOR THE HEAD-DISK INTERFACE IN CONTACT RECORDING DISK FILES. IN THE PREFERRED PROCESS FOR FORMING THE NI0 FILM ON THE SUBSTRATE, THE SUBSTRATE IS ANNEALED IN AIR AT A TEMPERATURE BELOW THAT WHICH WOULD CAUSE THE NIP FILM TO CRYSTALLIZE.(FIG. 5)