US4766039A
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US
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Magnetic head made from amorphous magnetic film
Assignee: Hitachi Ltd
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Filing: 1986-06-17
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Granted: 1988-08-23
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Expires: 2006-06-17
Abstract
Abstract A magnetic head comprising a magnetic film in at least a part of a magnetic circuit, at least a part of the magnetic film being formed in contact with, or being exposed to, an oxide or oxygen at least in a heating step at 150 DEG C. or higher in a process for preparing the magnetic head is disclosed. An amorphous alloy film for the magnetic film has the following composition formula to give distinguished head characteristics without any oxidation: CoaTbZrcNd where T is at last one of Nb, Ta, W, Mo, V and Cr; N is at least one of Au, Pt and Ag; d>/=1, b>0, b1+b2+2c>/=10, a+d>/=80, -1</=(3c-b1-3b2-5b3-3b4-4d)/(c+b1+b2+b3+b4+d)</=1, and a+b+c+d=100, where b1 is a Nb concentration, b2 is a Ta concentration, b3 is a W concentration, b4 is sum total of Mo, Cr and V concentrations and b=b1+b2+b3+b4.
Inventors
- 👤 Shigekazu Otomo
- 👤 Noriyuki Kumasaka
- 👤 Noritoshi Saito
- 👤 Takeo Yamashita
- 👤 Kazuo Shiiki
- 👤 Yoshihiro Hamakawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 23:20
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/10; G11B5/11; G11B5/1278; G11B5/147; G11B5/31; G11B5/33; G11B5/39; Y; Y10; Y10S; Y10S428/00; Y10S428/90
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
134 words
A magnetic head comprising a magnetic circuit, at least a part of said magnetic circuit including a magnetic film, wherein said magnetic film is composed of an amorphous alloy film having the following composition formula: Co a T b Zr c N d wherein T is at least one of Nb, Ta, W, Mo, V, and Cr; N is at least one of Au, Pt and Ag; d≧1, b>0, b 1 +b 2 +2c≧10, a+d≧80, -1≦(3c-b 1 -3b 2 -5b 3 -3b 4 -4d)/(c+b 1 +b 2 +b 3 +b 4 +d)≦1, and a+b+c+d=100, where b 1 is a Nb concentration, b 2 is a Ta concentration, b 3 is a W concentration, b 4 is sum total of Mo, Cr and V concentrations, and b=b 1 +b 2 +b 3 +b 4 .
Claim 2
Dependent Claim
134 words
A magnetic head comprising a magnetic circuit, at least a part of said magnetic circuit including a magnetic film, wherein said magnetic film is composed of an amorphous alloy film having the following composition formula: Co a T b Zr c N d wherein T is at least one of Nb, Ta, W, Mo, V, and Cr; N is at least one of Au, Pt and Ag; d≧1, b>0, b 1 +b 2 +2c≧10, a+d≧80, -1≦(3c-b 1 -3b 2 -5b 3 -3b 4 -4d)/(c+b 1 +b 2 +b 3 +b 4 +d)≦1, and a+b+c+d=100, where b 1 is a Nb concentration, b 2 is a Ta concentration, b 3 is a W concentration, b 4 is sum total of Mo, Cr and V concentrations, and b=b 1 +b 2 +b 3 +b 4 .
Claim 3
Dependent Claim
35 words
A magnetic head according to claim 1, wherein said magnetic film is formed in contact with an oxide layer and is subjected to a heating step at an elevated temperature of at least 150° C.
Claim 4
Dependent Claim
34 words
A magnetic head according to claim 1, wherein said magnetic film is in contact with an oxygen-containing layer and is subjected to a heating step at an elevated temperature of at least 150° C.
Claim 5
Dependent Claim
31 words
A magnetic head according to claim 1, wherein said magnetic film is exposed to oxygen while being subjected to a heating step at an elevated temperature of at least 150° C.
Claim 6
Dependent Claim
118 words
A magnetic head according to claim 1, wherein the magnetic film is composed of an amorphous alloy film having the following composition formula: Co.sub.a T.sub.b Zr.sub.c N.sub.d wherein T is at least one of Nb, Ta, W, Mo, V and Cr; N is at least one of Au, Pt and Ag; d≧3, b>0, b 1 +b 2 +2c≧10, a+d≧80, -1≦(3c-b 1 -3b 2 -5b 3 -3b 4 -4d)/(c+b 1 +b 2 +b 3 +b 4 +d)≦1, and a+b+c+d=100, wherein b 1 is a Nb concentration, b 2 is a Ta concentration, b 3 is a W concentration, b 4 is sum total of Mo, Cr and V concentrations and b=b 1 +b 2 +b 3 +b 4 .
Claim 7
Dependent Claim
118 words
A magnetic head according to claim 5, wherein the magnetic film is composed of an amorphous alloy film having the following composiiton formula: Co.sub.a T.sub.b Zr.sub.c N.sub.d wherein T is at least one of Nb, Ta, W, Mo, V and Cr; N is at least one of Au, Pt and Ag; d≧3, b>0, b 1 +b 2 +2c≧10, a+d≧80, -0.5≦(3c-b 1 -3b 2 -5b 3 -3b 4 -4d)/(c+b 1 +b 2 +b 3 +b 4 +d)≦0.5, and a+b+c+d=100, where b 1 is a Nb concentration, b 2 is a Ta concentration, b 3 is a W concentration, b 4 is sum total of Mo, Cr and V concentrations and b=b 1 +b 2 +b 3 +b 4 .
Claim 8
Dependent Claim
130 words
A magnetic head comprising a magnetic shield, at least a part of said magnetic shield including a magnetic film, wherein said magnetic film is composed of an amorphous alloy film having the following composition formula: Co.sub.a T.sub.b Zr.sub.c N.sub.d wherein T is at least one of Nb, Ta, W, Mo, V, and Cr; N is at least one of Au, Pt and Ag; d≧1, b>0, b 1 +b 2 +2c≧10, a+d≧80, -1≦(3c-b 1 -3b 2 -5b 3 -3b 4 -4d)/(c+b 1 +b 2 +b 3 +b 4 +d)≦1, and a+b+c+d=100, where b 1 is a Nb concentration, b 2 is a Ta concentration, b 3 is a W concentration, b 4 is sum total of Mo, Cr and V concentrations, and b=b 1 +b 2 +b 3 +b 4 .
Claim 9
Dependent Claim
130 words
A magnetic head comprising a magnetic shield, at least a part of said magnetic shield including a magnetic film, wherein said magnetic film is composed of an amorphous alloy film having the following composition formula: Co.sub.a T.sub.b Zr.sub.c N.sub.d wherein T is at least one of Nb, Ta, W, Mo, V, and Cr; N is at least one of Au, Pt and Ag; d≧1, b>0, b 1 +b 2 +2c≧10, a+d≧80, -1≦(3c-b 1 -3b 2 -5b 3 -3b 4 -4d)/(c+b 1 +b 2 +b 3 +b 4 +d)≦1, and a+b+c+d=100, where b 1 is a Nb concentration, b 2 is a Ta concentration, b 3 is a W concentration, b 4 is sum total of Mo, Cr and V concentrations, and b=b 1 +b 2 +b 3 +b 4 .
Claim 10
Dependent Claim
35 words
A magnetic head according to claim 7, wherein said magnetic film is formed in contact with an oxide layer and is subjected to a heating step at an elevated temperature of at least 150° C.
Claim 11
Dependent Claim
34 words
A magnetic head according to claim 7, wherein said magnetic film is in contact with an oxygen-containing layer and is subjected to a heating step at an elevated temperature of at least 150° C.
Claim 12
Dependent Claim
31 words
A magnetic head according to claim 7, wherein said magnetic film is exposed to oxygen while being subjected to a heating step at an elevated temperature of at least 150° C.
Claim 13
Dependent Claim
15 words
A magnetic head according to claim 7, wherein said magnetic head is a magnetoresistive head.
Claim 14
Dependent Claim
118 words
A magnetic head according to claim 7, wherein the magnetic film is composed of an amorphous alloy film having the following composition formula: Co.sub.a T.sub.b Zr.sub.c N.sub.d wherein T is at least one of Nb, Ta, W, Mo, V, and Cr; N is at least one of Au, Pt and Ag; d≧3, b>0, b 1 +b 2 +2c≧10, a+d≧80, -1≦(3c-b 1 -3b 2 -5b 3 -3b 4 -4d)/(c+b 1 +b 2 +b 3 +b 4 +d)≦1, and a+b+c+d=100, where b 1 is a Nb concentration, b 2 is a Ta concentration, b 3 is a W concentration, b 4 is sum total of Mo, Cr and V concentrations, and b=b 1 +b 2 +b 3 +b 4 .
Claim 15
Dependent Claim
118 words
A magnetic head according to claim 12, wherein the magnetic film is composed of an amorphous alloy film having the following composition formula: Co.sub.a T.sub.b Zr.sub.c N.sub.d wherein T is at least one of Nb, Ta, W, Mo, V, and Cr; N is at least one of Au, Pt and Ag; d≧3, b>0, b 1 +b 2 +2c≧10, a+d≧80, -0.5≦(3c-b 1 -3b 2 -5b 3 -3b 4 -4d)/(c+b 1 +b 2 +b 3 +b 4 +d)≦0.5, and a+b+c+d=100, where b 1 is a Nb concentration, b 2 is a Ta concentration, b 3 is a W concentration, b 4 is sum total of Mo, Cr and V concentrations, and b=b 1 +b 2 +b 3 +b 4 .
Claim 16
Dependent Claim
116 words
A magnetic shield for a magnetoresistive head comprising a shield film formed of an amorphous alloy having the following composition formula: Co.sub.a T.sub.b Zr.sub.c N.sub.d wherein T is at least one of Nb, Ta, W, Mo, V, and Cr; N is at least one of Au, Pt and Ag; d≧1, b>0, b 1 +b 2 +2c≧10, a+d≧80, -1≦(3c-b 1 -3b 2 -5b 3 -3b 4 -4d)/(c+b 1 +b 2 +b 3 +b 4 +d)≦1, and a+b+c+d=100, where b 1 is a Nb concentration, b 2 is a Ta concentration, b 3 is a W concentration, b 4 is sum total of Mo, Cr and V concentrations, and b=b 1 +b 2 +b 3 +b 4 .
Claim 17
Dependent Claim
116 words
A magnetic shield for a magnetoresistive head comprising a shield film formed of an amorphous alloy having the following composition formula: Co.sub.a T.sub.b Zr.sub.c N.sub.d wherein T is at least one of Nb, Ta, W, Mo, V, and Cr; N is at least one of Au, Pt and Ag; d≧1, b>0, b 1 +b 2 +2c≧10, a+d≧80, -1≦(3c-b 1 -3b 2 -5b 3 -3b 4 -4d)/(c+b 1 +b 2 +b 3 +b 4 +d)≦1, and a+b+c+d=100, where b 1 is a Nb concentration, b 2 is a Ta concentration, b 3 is a W concentration, b 4 is sum total of Mo, Cr and V concentrations, and b=b 1 +b 2 +b 3 +b 4 .
Claim 18
Dependent Claim
36 words
A magnetic shield according to claim 14, wherein said shield film is formed in contact with an oxide layer and is subjected to a heating step at an elevated temperature of at least least 150° C.
Claim 19
Dependent Claim
34 words
A magnetic shield according to claim 14, wherein said shield film is in contact with an oxygen-containing layer and is subjected to a heating step at an elevated temperature of at least 150° C.
Claim 20
Dependent Claim
31 words
A magnetic shield according to claim 14, wherein said sheild film is exposed to oxygen while being subjected to a heating step at an elevated temperature of at least 150° C.
Claim 21
Dependent Claim
118 words
A magnetic shield according to claim 14, wherein the shield film is composed of an amorphous alloy film having the following composition formula: Co.sub.a T.sub.b Zr.sub.c N.sub.d wherein T is at least one of Nb, Ta, W, Mo, V, and Cr; N is at least one of Au, Pt and Ag; d≧3, b>0, b 1 +b 2 +2c≧10, a+d≧80, -1≦(3c-b 1 -3b 2 -5b 3 -3b 4 -4d)/(c+b 1 +b 2 +b 3 +b 4 +d)≦1, and a+b+c+d=100, where b 1 is a Nb concentration, b 2 is a Ta concentration, b 3 is a W concentration, b 4 is sum total of Mo, Cr and V concentrations, and b=b 1 +b 2 +b 3 +b 4 .
Claim 22
Dependent Claim
118 words
A magnetic shield according to claim 18, wherein the shield film is composed of an amorphous alloy film having the following composition formula: Co.sub.a T.sub.b Zr.sub.c N.sub.d wherein T is at least one of Nb, Ta, W, Mo, V, and Cr; N is at least one of Au, Pt and Ag; d≧3, b>0, b 1 +b 2 +2c≧10, a+d≧80, -0.5≦(3c-b 1 -3b 2 -5b 3 -3b 4 -4d)/(c+b 1 +b 2 +b 3 +b 4 +d)≦0.5, and a+b+c+d=100, where b 1 is a Nb concentration, b 2 is a Ta concentration, b 3 is a W concentration, b 4 is sum total of Mo, Cr and V concentrations, and b=b 1 +b 2 +b 3 +b 4 .
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