Method of making a magnetic memory device

Claim 1

THE METHOD OF FORMING A MAGNETIC COATING COMPRISING AN ALLOY OF IRON-NICKEL-COBALT ON A CONDUCTIVE SUBSTRATE WHICH HAS AN ANISOTROPIC FIELD CHARACTERISTIC ADJACENT THE SURFACE OF SAID SUBSTRATE WHICH IS SUBSTANTIALLY HIGHER THAN THE ANISTROPIC FIELD CHARACTERISTIC OF SAID COATING ADJACENT THE OUTER SURFACE THEREOF COMPRISING THE STEPS OF: A. IMMERSING SAID SUBSTRATE IN A PLATING ELECTROLYTE CONTAINING IRON, NICKEL AND COBALT SALTS AND IN WHICH THE COBALT SALT CONCENTRATION IS SUFFICIENTLY HIGH TO DEPOSIT AN IRONNICKEL-COBALT ALLOY CONTAINING FIBER PERCENT OR MORE OF COBALT ONTO SAID SUBSTRATE; B. PASSING A PLATING CURRENT THROUGH SAID ELECTROLYTE TO SAID SUBSTRATE; C. INITIALLY PRODUCING A FLOW OF SAID ELECTROLYTE PAST THE SURFACE OF SAID SUBSTRATE AT A FIRST VELOCITY; D. SUBSEQUENTLY PRODUCING A VELOCITY OF FLOW OF SAID ELECTROLYTE PAST THE SURFACE OF SAID SUBSTRATE AT A SECOND VELOCITY, SAID SECOND VELOCITY BEING GREATER THAN SAID FIRST VELOCITY AND PRODUCING AN IRON-NICKEL-COBALT ALLOY COATING COMPRISING 5 PERCENT OR MORE COBALT HAVING AN ANISOTROPIC FIELD CHARACTERISTIC ON THE ORDER OF 6 OERSTEDS OR HIGHER DEPOSITED ON SAID SUBSTRATE DURING SAID INITIAL PERIOD AND A REGION OF SAID COATING HAVING AN ANISOTROPIC FIELD CHARACTERISTIC OF 4 OERSTEDS OR LOWER DEPOSITED ON SAID SUBSTRATE IN THE SUBSEQUENT PERIOD.

Claim 2

THE METHOD OF FORMING A MAGNETIC COATING COMPRISING AN ALLOY OF IRON-NICKEL-COBALT ON A CONDUCTIVE SUBSTRATE WHICH HAS AN ANISOTROPIC FIELD CHARACTERISTIC ADJACENT THE SURFACE OF SAID SUBSTRATE WHICH IS SUBSTANTIALLY HIGHER THAN THE ANISTROPIC FIELD CHARACTERISTIC OF SAID COATING ADJACENT THE OUTER SURFACE THEREOF COMPRISING THE STEPS OF: A. IMMERSING SAID SUBSTRATE IN A PLATING ELECTROLYTE CONTAINING IRON, NICKEL AND COBALT SALTS AND IN WHICH THE COBALT SALT CONCENTRATION IS SUFFICIENTLY HIGH TO DEPOSIT AN IRONNICKEL-COBALT ALLOY CONTAINING FIBER PERCENT OR MORE OF COBALT ONTO SAID SUBSTRATE; B. PASSING A PLATING CURRENT THROUGH SAID ELECTROLYTE TO SAID SUBSTRATE; C. INITIALLY PRODUCING A FLOW OF SAID ELECTROLYTE PAST THE SURFACE OF SAID SUBSTRATE AT A FIRST VELOCITY; D. SUBSEQUENTLY PRODUCING A VELOCITY OF FLOW OF SAID ELECTROLYTE PAST THE SURFACE OF SAID SUBSTRATE AT A SECOND VELOCITY, SAID SECOND VELOCITY BEING GREATER THAN SAID FIRST VELOCITY AND PRODUCING AN IRON-NICKEL-COBALT ALLOY COATING COMPRISING 5 PERCENT OR MORE COBALT HAVING AN ANISOTROPIC FIELD CHARACTERISTIC ON THE ORDER OF 6 OERSTEDS OR HIGHER DEPOSITED ON SAID SUBSTRATE DURING SAID INITIAL PERIOD AND A REGION OF SAID COATING HAVING AN ANISOTROPIC FIELD CHARACTERISTIC OF 4 OERSTEDS OR LOWER DEPOSITED ON SAID SUBSTRATE IN THE SUBSEQUENT PERIOD.

Claim 5

The method comprising the steps of: a. immersing a conductive wire in a first plating electrolyte comprising cobalt salts in a sufficient concentration to deposit an iron-nickel-cobalt alloy containing 5 percent or more of cobalt; b. passing plating current through said electrolyte to said wire; c. introducing said electrolyte to said wire by one or more streams at an acute angle to an axis perpendicular to said wire and in a direction to impart a component of velocity of electrolyte in one direction along said wire, said angle being between 25* and 30*; d. subsequently immersing said wire in a second plating electrolyte comprising cobalt salts in a sufficient concentration to deposit an iron-nickel-cobalt alloy containing 0.5 to 1.5 percent of cobalt; e. passing plating current through said electrolyte to said wire; and f. said second electrolyte being introduced to said wire through one or more streams at a substantially right angle to said wire.

Claim 6

The method comprising the steps of: a. immersing a conductive wire in a first plating electrolyte comprising cobalt salts in a sufficient concentration to deposit an iron-nickel-cobalt alloy containing 5 percent or more of cobalt; b. passing plating current through said electrolyte to said wire; c. introducing said electrolyte to said wire by one or more streams at an acute angle to an axis perpendicular to said wire and in a direction to impart a component of velocity of electrolyte in one direction along said wire, said angle being between 25* and 30*; d. subsequently immersing said wire in a second plating electrolyte comprising cobalt salts in a sufficient concentration to deposit an iron-nickel-cobalt alloy containing 0.5 to 1.5 percent of cobalt; e. passing plating current through said electrolyte to said wire; and f. said second electrolyte being introduced to said wire through one or more streams at a substantially right angle to said wire.