Alloy and Sputtering Target Material for Soft-Magnetic Film Layer in Perpendicular Magnetic Recording Medium, and Method for Producing the Same

• US 20090071822A1
• Filed: 09/17/2008
• Published: 03/19/2009
• Est. Priority Date: 09/18/2007
• Status: Abandoned Application

• Current Assignee: Sanyo Special Steel Company Limited (Nippon Steel Corporation)
• Original Assignee: Sanyo Special Steel Company Limited (Nippon Steel Corporation)
• Inventors: Sawada, Toshiyuki, Yanagitani, Akihiko
• Application Number:
  US12/212,329
• Publication Number:
  US 20090071822A1
• Time in Patent Office: Days
• US Class Current: 204/298.130
• CPC Class Codes: B22F 1/09 Mixtures of metallic powders
• CPC Class Codes: B22F 2998/10 Processes characterised by the sequence of their steps
• CPC Class Codes: B22F 3/14 simultaneously
• CPC Class Codes: C22C 1/0433 Nickel- or cobalt-based alloys
• CPC Class Codes: C22C 33/0257 characterised by the range of the alloying elements
• CPC Class Codes: C23C 14/3414 Metallurgical or chemical aspects of target preparation, e.g. casting, powder metallurgy
• CPC Class Codes: H01F 41/183 Sputtering targets therefor

Abstract

There are provided a sputtering target material for a soft-magnetic film layer with a high saturation magnetic flux density and high amorphous properties and a method for producing the sputtering target material. The target material is made of an alloy comprising one or more of Zr, Hf, Nb, Ta and B in an amount satisfying 5 at %≦(Zr+Hf+Nb+Ta)+B/2≦10 at % and having 7 at % or less of B; 0 to 5 at % in total of Al and Cr; and the balance being Co and Fe in an amount satisfying 0.20≦Fe/(Fe+Co)≦0.65 (at % ratio) with unavoidable impurities.

Claims

1. A sputtering target material for a soft-magnetic film layer in a perpendicular magnetic recording medium, the target being made of an alloy comprising:

one or more of Zr, Hf, Nb, Ta and B in an amount satisfying 5 at %≦

(Zr+Hf+Nb+Ta)+B/2≦

10 at % and having 7 at % or less of B;

Al and Cr;

0 to 5 at % in total; and

the balance being Co and Fe in an amount satisfying 0.20≦

Fe/(Fe+Co)≦

0.65 (at % ratio) with unavoidable impurities.

2. A method for producing a sputtering target material according to claim 1, comprising the steps of:

a) mixing a first powder and a second powder to form a mixed powder, wherein the first powder comprises;

one or more of Zr, Hf, Nb, Ta and B in an amount satisfying 3 at %≦

(Zr+Hf+Nb+Ta)+B/2≦

12 at %;

Al and Cr;

0 to 5 at % in total; and

the balance being Co and Fe in an amount of satisfying 1.00≧

Fe/(Fe+Co)≧

0.90 (at % ratio) with unavoidable impurities, and wherein the second powder comprises;

one or more of Zr, Hf, Nb, Ta and B having an amount of satisfying 3 at %≦

(Zr+Hf+Nb+Ta)+B/2≦

12 at %;

Al and Cr;

0 to 5 at % in total; and

the balance being Co and Fe in an amount satisfying 0.00≦

Fe/(Fe+Co)≦

0.10 (at % ratio) with unavoidable impurities; and

b) consolidating the mixed powder at 800 to 1250°

C. and at 100 to 1000 MPa to form the sputtering target material.

3. The method according to claim 2, wherein only the first powder or both of the first powder and the second powder comprise 5 at % or less of Al+Cr, and wherein the target material comprises 5 at % or less of Al+Cr as a whole.

4. The method according to claim 2, wherein a difference between a PTF value of the target material and a PFT value of a target material produced by the same method as the method according to claim 2 except for using a single powder of the same composition as a final composition of the target material in place of the mixed powder ranges from 5 to 15.

5. A sputtering target material for a soft-magnetic film layer in a perpendicular magnetic recording medium produced by the method according to claim 2.

6. A sputtering target material for a soft-magnetic film layer in a perpendicular magnetic recording medium produced by the method according to claim 3.

7. The method according to claim 3, wherein a difference between a PTF value of the target material and a PFT value of a target material produced by the same method as the method according to claim 3 except for using a single powder of the same composition as a final composition of the target material in place of the mixed powder ranges from 5 to 15.