MAGNETIC MEDIA HAVING A SERVO TRACK WRITTEN WITH A PATTERNED MAGNETIC RECORDING HEAD
A thin film magnetic recording head utilizing a timing based servo pattern is fabricated using a focused ion beam (FIB). The recording head is fabricated by sputtering a magnetically permeable thin film onto a substrate. A gap pattern, preferably a timing based pattern, is defined on the thin film and the FIB cuts a gap through the thin film based on that pattern. Once completed, the recording head is used to write a servo track onto magnetic tape. The timing based servo track then allows for the precise alignment of data read heads based on the positional information obtained by a servo read head which scans the continuously variable servo track.
1 . A magnetic media having a timing based servo track written by a magnetic recording head having a timing based gap pattern, the magnetic recording head comprising:
a substrate;
a magnetically permeable thin film deposited onto the substrate; and
a gap pattern milled through the magnetically permeable thin film using a focused ion beam, wherein the gap pattern formed by the focused ion beam is matched to a visually defined gap pattern and wherein the focused ion beam is oriented in a direction that is parallel with a resulting gap depth through the magnetically permeable thin film.
2 . The magnetic media of claim 1 , wherein the magnetic media is magnetic tape.
3 . The magnetic media of claim 1 , wherein the recording head further comprises a coil coupled to the substrate, wherein the coil controllably causes magnetic flux to flow through the substrate and the thin film.
4 . The magnetic media of claim 1 , wherein the substrate of the recording head further comprises a pair of ferrite blocks bonded to a ceramic member wherein an upper surface of the bonded blocks and ceramic member is polished.
5 . The magnetic media of claim 4 , wherein the upper surface of the recording head has a curvature.
6 . The magnetic media of claim 1 , wherein the thin film of the recording head includes material sputtered onto the substrate to produce the thin film.
7 . The magnetic media of claim 6 , wherein the sputtered material of the recording head has a high magnetic moment density.
8 . The magnetic media of claim 6 , wherein the sputtered material of the Recording head is chosen from the family of iron nitride alloys.
9 . The magnetic media of claim 6 , wherein the sputtered material of the recording head is FeXN.
10 . The magnetic media of claim 6 , wherein the sputtered material of the recording head is FeAlN.
11 . The magnetic media of claim 6 , wherein the sputtered material of the recording head is FeTaN.
12 . The magnetic media of claim 6 , wherein the sputtered material of the recording head is sputtered to form a thin film having a thickness between 1 to 5 μm.
13 . The magnetic media of claim 1 , wherein the gap pattern of the recording head is defined by a visual indication of the pattern on the thin film.
14 . The magnetic media of claim 13 , wherein the gap pattern of the recording head is a timing based servo pattern.
15 . The magnetic media of claim 13 , wherein the visual indication of the recording head is provided by an applied layer of photoresist over at least a portion of the thin film, wherein the photoresist is masked and a portion of the photoresist is removed using a chemical process.
16 . The magnetic media of claim 15 , wherein the gap pattern defined on the recording head is a timing based servo pattern.
17 . The magnetic media of claim 1 , wherein the gap pattern of the recording head is defined by entering the numerical coordinates of the gap pattern into a control system of the focused ion beam, wherein the visually defined pattern provides a reference point from which numerical coordinates are based.
18 . The magnetic media of claim 17 , wherein the gap pattern defined on the recording head is a timing based servo pattern.
19 . The magnetic media of claim 1 , wherein the focused ion beam is substantially perpendicular to an upper major surface of the thin film of the recording head during milling.
20 . The magnetic media of claim 19 , wherein the gap of the recording head has nearly vertical side walls.
21 . The magnetic media of claim 1 , wherein the gap of the recording head has nearly vertical side walls.
22 . A magnetic tape having a timing based servo pattern written thereon by a magnetic recording head having a timing based pattern, the magnetic recording head comprising:
a magnetically permeable substrate having two ferrite blocks glass bonded to a medially disposed ceramic member;
a magnetically permeable thin film sputtered onto one surface of the substrate thereby providing a major surface, wherein a focused ion beam is rastered in a plane orthogonal to the plane of the major surface of the thin film and parallel to a gap depth, milling out the thin film defined by a visually defined gap pattern, wherein the gap pattern formed by the focused ion beam is matched to the visually defined pattern; and
a coil coupled to the substrate, wherein the coil controllably causes magnetic flux to flow through the substrate and the thin film.
23 . The magnetic tape of claim 22 , wherein the thin film of the recording head is FeXN.
24 . The magnetic tape of claim 22 , wherein the thin film of the recording head is FeAlN.
25 . The magnetic tape of claim 22 , wherein the thin film of the recording head is FeTaN.
26 . The magnetic tape of claim 22 , wherein the gap pattern of the recording head is defined by a deposited layer of photoresist on at least a portion of the thin film, wherein the photoresist is masked and a portion of the photoresist is removed using photolithography.
27 . The magnetic tape of claim 22 , wherein the gap pattern of the recording head is defined by a visual indication of the pattern on the thin film.
28 . The magnetic tape of claim 22 , wherein the pattern of the recording head is defined within a control system of the focused ion beam.
29 . The magnetic tape of claim 22 , wherein the pattern of the recording head is defined within the control system by entering the numerical coordinates of the gap to be milled, wherein the visually defined pattern provides a reference point from which numerical coordinates are based.
30 . The magnetic tape of claim 22 , wherein the gap of the recording head has nearly vertical side walls.