Servo write head
View Patent ↗A servo write head for magnetic tape is provided. The invention includes first and second non-magnetic substrates and first and second magnetic layers deposited between the non-magnetic substrates. A middle non-magnetic substrate is then deposited between the first and second magnetic layers and forms the magnetic gap. In one embodiment, non-magnetic protective layers are placed between the middle substrate and magnetic layers and form part of the gap. A contoured top layer of magnetic material is deposited across the other layers and substrates and has at least one recording gap, and wherein the top layer forms a magnetic pattern for writing a servo pattern to the tape.
1. A servo write head for magnetic tape, the servo write head comprising:
first and second non-magnetic substrates;
first and second magnetic layers deposited between the first and second non-magnetic substrates;
a third non-magnetic substrate deposited between the first and second magnetic layers, wherein the third non-magnetic substrate forms a magnetic gap;
an inductive wire coil operatively disposed with respect to the first, second, and third non-magnetic substrates and the first and second magnetic layers; and
a third, contoured, top layer of magnetic material deposited across the first, second, and third non-magnetic substrates and the first and second magnetic layers, wherein the top layer has at least one recording gap, and wherein the top layer and recording gap form a magnetic field pattern to form a recorded servo pattern on the tape when electric current is fed through the coil.
2. The servo write head according to claim 1 , further comprising:
first and second non-magnetic protective layers, wherein the first and second protective layers form part of the magnetic gap;
wherein the first protective layer is deposited between the first magnetic layer and third non-magnetic substrate; and
wherein the second protective layer is deposited between the second magnetic layer and third non-magnetic substrate.
3. The servo write head according to claim 2 , wherein the first and second protective layers are composed of one of the following:
Al 2 O 3 ;
Si 3 N 4 ;
SiO 2 ;
TI;
AU;
Cu; and
Al.
4. The servo write head according to claim 1 , further comprising a magnetic flux closure substrate bonded to the bottom of the servo write head opposite the third top layer.
5. The servo write head according to claim 4 , wherein the magnetic flux closure is composed of magnetic material.
6. The servo write head according to claim 5 , wherein the magnetic flux closure is composed of ferrite.
7. The servo write head according to claim 4 , wherein the magnetic flux closure is composed of a non-magnetic substrate coated with magnetic material.
8. The servo write head according to claim 7 , wherein the magnetic flux closure is composed of Al 2 O 3 TiC coated with one of the following:
ferrite;
NiFe;
CoZrTa; and
FeN.
9. The servo write head according to claim 1 , wherein the servo write head has a channel within the third non-magnetic substrate through which the inductive wire passes.
10. The servo write head according to claim 1 , wherein the third top layer of magnetic material has a plurality of recording gaps.
11. The servo write head according to claim 1 , wherein the non-magnetic substrates and first and second magnetic layers are part of a thin-film wafer.
12. The servo write head according to claim 1 , wherein the first and second non-magnetic substrates are composed of Al 2 O 3 TiC.
13. The servo write head according to claim 1 , wherein the third non-magnetic substrate is composed one of the following:
Al 2 O 3 TiC;
glass;
copper;
SiC;
sapphire; and
barium titanate.
14. The servo write head according to claim 1 , wherein the first and second magnetic layers are composed of one of the following:
CoZrTa; and
NiFe.
15. The servo write head according to claim 1 , wherein the third, top, magnetic layer is composed of one of the following:
NiFe;
CoZrTa; and
FeN.