Substrate for thin-film magnetic head
View Patent ↗A thin-film magnetic head substrate includes a ceramic base, an undercoat film of an aluminum oxide, and an intermediate layer, which is sandwiched between the ceramic base and the undercoat film and which is made of a material other than the aluminum oxide and an Al—Ti—O compound.
1. A thin-film magnetic head substrate comprising:
a ceramic base;
an undercoat film of an aluminum oxide; and
an intermediate layer, which is sandwiched between the ceramic base and the undercoat film and which is made of a material other than the aluminum oxide and a material other than an Al—Ti—O compound; wherein
the intermediate layer is metal or a material consisting of Si; and
the undercoat film has a thickness of 10 nm to 0.4 μm.
2. The thin-film magnetic head substrate of claim 1 , wherein the intermediate layer has a thickness of 1 nm to 1 μm.
3. The thin-film magnetic head substrate of claim 1 , wherein the intermediate layer is made of a material selected from the group consisting of Cu, Cr, alloys including Cu, and alloys including Cr.
4. The thin-film magnetic head substrate of claim 1 , wherein the ceramic base is made of an alumina-based ceramic material including 24 mol % to 75 mol % of α-Al 2 O 3 and at most 2 mol % of an additive.
5. The thin-film magnetic head substrate of claim 4 , wherein the ceramic base further includes a carbide or nitride carbonate of a metal.
6. A thin-film magnetic head slider comprising:
a thin-film magnetic head substrate including:
a ceramic base;
an undercoat film of an aluminum oxide; and
an intermediate layer, which is sandwiched between the ceramic base and the undercoat film and which is made of a material other than the aluminum oxide and a material other than an AI—Ti—O compound; and
a read head and a write head, which are supported on the thin-film magnetic head substrate; wherein
the intermediate layer is metal or a material consisting of Si; and
the undercoat film has a thickness of 10 nm to 0.4 μm.
7. A hard disk drive comprising:
a thin-film magnetic head slider including:
a thin-film magnetic head substrate including:
a ceramic base;
an undercoat film of an aluminum oxide; and
an intermediate layer, which is sandwiched between the ceramic base and the undercoat film and which is made of a material other than the aluminum oxide and a material other than an AI—Ti—O compound; and
a read head and a write head, which are supported on the thin-film magnetic head substrate; wherein
the intermediate layer is metal or a material consisting of Si; and
the undercoat film has a thickness of 10 nm to 0.4 μm.
8. A thin-film magnetic head substrate comprising:
a ceramic base;
an undercoat film of an aluminum oxide; and
an intermediate layer, which is sandwiched between the ceramic base and the undercoat film and which is made of a material other than the aluminum oxide and a material other than an Al—Ti—O compound; wherein
the intermediate layer is metal or a material consisting of Si;
the undercoat film has a thickness of 10 nm to 0.4 μm; and
the ceramic base has a volume resistivity of about 1×10 −5 Ω·cm to about 1×10 9 Ω·cm.