MAGNETIC HEAD
According to an aspect of an embodiment, a magnetic head includes: a write element including a first magnetic pole and a second magnetic pole magnetically connected to the first magnetic pole; and a nonmagnetic insulating layer made of inorganic material surrounding the write element. The magnetic head further includes: upper and lower low-thermal-expansion material layers disposed on and under the nonmagnetic insulating layer, respectively, the low-thermal-expansion material layers having a thermal coefficient lower than that of the nonmagnetic insulating layer; and a heater element embedded in the nonmagnetic insulating layer.
1 . A magnetic head comprising:
a write element including a first magnetic pole and a second magnetic pole magnetically connected to the first magnetic pole;
a nonmagnetic insulating layer made of inorganic material surrounding the write element;
upper and lower low-thermal-expansion material layers disposed on and under the nonmagnetic insulating layer, respectively, the low-thermal-expansion material layers having a thermal coefficient lower than that of the nonmagnetic insulating layer; and
a heater element embedded in the nonmagnetic insulating layer.
2 . The magnetic head according to claim 1 , further comprising:
a substrate under the lower low-thermal-expansion material layer, wherein the distance between the heater element and the upper low-thermal-expansion material layer is longer than that between the heater element and the lower low-thermal-expansion material layer.
3 . The magnetic head according to claim 1 , wherein the nonmagnetic insulating layer includes aluminum oxide.
4 . The magnetic head according to claim 1 , wherein the lower low-thermal-expansion material layer and the upper low-thermal-expansion material layer have a higher thermal conductivity than the nonmagnetic insulating layer.
5 . The magnetic head according to claim 2 , wherein the substrate have a higher thermal conductivity than the nonmagnetic insulating layer.
6 . The magnetic head according to claim 1 , further comprising:
a magnetic coil between the first and second magnetic poles, the magnetic coil being capable of inducing a magnetic flux through the first and second magnetic poles.
7 . The magnetic head according to claim 6 , wherein the heater element is disposed between the magnetic coil and the lower low-thermal-expansion material layer.
8 . The magnetic head according to claim 7 , wherein the first magnetic pole is above the second magnetic pole and the heater element is disposed between the magnetic coil and the second magnetic pole.
9 . The magnetic head according to claim 2 , further comprising:
a read element disposed between the lower low-thermal-expansion material layer and the write element.
10 . The magnetic head according to claim 9 , wherein the first magnetic pole is above the second magnetic pole and the heater element is disposed between the second magnetic pole and the read element.
11 . The magnetic head according to claim 2 , further comprising:
a read element disposed under the lower low-thermal-expansion material layer.
12 . The magnetic head according to claim 11 , wherein the heater element is disposed between the second magnetic pole and the lower low-thermal-expansion material layer.
13 . A head slider comprising:
a write element including a first magnetic pole and a second magnetic magnetically connected to the first magnetic pole;
a nonmagnetic insulating layer made of inorganic material surrounding the write element;
upper and lower low-thermal-expansion material layers disposed on and under the nonmagnetic insulating layer, respectively, the low-thermal-expansion material layers having a thermal coefficient lower than that of the nonmagnetic insulating layer, the lower low-thermal-expansion material layer being on the substrate;
a substrate under the lower low-thermal-expansion material layer; and
a heater element embedded in the nonmagnetic insulating layer.
14 . The head slider according to claim 13 , further comprising:
a nonmagnetic insulating layer deposited on the substrate so as to cover the lower low-thermal-expansion material layer, the read element, the write element, the upper low-thermal-expansion material layer, and the heater element.
15 . A storage device comprising:
a storage medium; and
a head slider so as to face the storage medium, the head slider including:
a write element including a first magnetic pole and a second magnetic magnetically connected to the first magnetic pole;
a nonmagnetic insulating layer made of inorganic material surrounding the write element;
upper and lower low-thermal-expansion material layers disposed on and under the nonmagnetic insulating layer, respectively, the low-thermal-expansion material layers having a thermal coefficient lower than that of the nonmagnetic insulating layer, the lower low-thermal-expansion material layer being on the substrate;
a substrate under the lower low-thermal-expansion material layer; and
a heater element embedded in the nonmagnetic insulating layer.
16 . The storage device according to claim 15 , wherein the head slider further includes a nonmagnetic insulating layer deposited on the substrate so as to cover the lower low-thermal-expansion material layer, the read element, the write element, the upper low-thermal-expansion material layer, and the heater element.