Thin film magnetic media for minimal lubricant transfer to head during flying
AssigneeSeagate Technology LLC
InventorsJing Gui, Bruno J. Marchon, Dallas W. Meyer, Peter Segar
Life of this patent
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Abstract
A light abrasive texture is applied over the data zone of a thin film magnetic disc, while a surface texture of a second roughness is applied over the landing zone. A lubricant is applied over both the landing zone and the data zone. The lubricant is a high molecular weight PFPE lubricant which has been fractionated by supercritical fluid fractionation in carbon dioxide to exclude the fractions of low molecular weight and to exclude the fractions of very high molecular weight.
Claims24
A thin film magnetic disc for a computer disc drive, the computer disc drive having an air bearing read/write head mounted on an actuator arm adjacent a surface of the thin film magnetic disc, the thin film magnetic disc comprising:
- landing zone on the thin film magnetic disc, the landing zone having a first roughness;
- a data zone on the thin film magnetic disc and located outward from the landing zone, the data zone being adapted to magnetically record information via the air bearing read/write head, the data zone having a second surface roughness which is less than the first surface roughness of the landing zone;
- and
- a lubricant over both the landing zone and the data zone, the lubricant having been fractionated to exclude fractions of high molecular weight relative to molecular weights of the lubricant prior to fractionation.
A thin film magnetic disc for a computer disc drive, the computer disc drive having an air bearing read/write head mounted on an actuator arm adjacent a surface of the thin film magnetic disc, the thin film magnetic disc comprising:
- a landing zone defined on the thin film magnetic disc, the landing zone having a first surface roughness;
- a data zone defined on the thin film magnetic disc and located outward from the landing zone, the data zone being adapted to magnetically record information via the air bearing read/write head, the data zone having a second surface roughness;
- and
- a lubricant over both the landing zone and the data zone, wherein the lubricant is PFPE lubricant which has been fractionated to exclude fractions of high molecular weight relative to molecular weights of the lubricant prior to fractionation.
A method of manufacturing a thin film magnetic disc for a computer disc drive, the computer disc drive having an air bearing read/write head mounted on an actuator arm adjacent a surface of the thin film magnetic disc, the method comprising:
- providing a thin film magnetic disc adapted to magnetically record information via the air bearing read/write head;
- roughening a landing zone on the thin film magnetic disc with a roughness average Ra of greater than 100 Angstroms;
- roughening a data zone on the thin film magnetic disc outward from the landing zone, with a roughness average Ra of at least 15 Angstroms;
- fractionating PFPE lubricant into a first molecular weight fraction, a second molecular weight fraction and a third molecular weight fraction, the second fraction including molecular weights which are higher than molecular weights of the first molecular weight fraction and lower than molecular weights of the third molecular weight fraction;
- and
- applying the second molecular weight fraction to the roughened landing zone and the roughened data zone.
A thin film magnetic disc for a computer disc drive, the computer disc drive having an air bearing read/write head mounted on an actuator arm adjacent a surface of the thin film magnetic disc, the thin film magnetic disc comprising:
- a landing zone on the thin film magnetic disc, the landing zone having a first roughness;
- a data zone on the thin film magnetic disc and located outward from the landing zone, the data zone being adapted to magnetically record information via the air bearing read/write head, the data zone having a second surface roughness which is less than the first surface roughness of the landing zone;
- and
- a lubricant over both the landing zone and the data zone, the lubricant having been fractionated to exclude fractions of high molecular weight relative to molecular weights of the lubricant prior to fractionation, wherein the lubricant is a PFPE lubricant which has also been fractionated to excluded fractions of low molecular weight relative to molecular weights of the lubricant prior to fractionation, wherein the lubricant has been fractionated to exclude fractions of greater than about 4000 a.m.u., wherein the lubricant has also been fractionated by supercritical fluid fractionation using carbon dioxide to exclude fractions of less than about 1200 a.m.u., and wherein the second roughness has a roughness average Ra of at least 15 Angstroms.
A thin film magnetic disc for a computer disc drive, the computer disc drive having an air bearing read/write head mounted on a actuator arm adjacent a surface of the thin film magnetic disc, the thin film magnetic disc comprising:
- a landing zone defined on the thin film magnetic disc, the landing zone having a first surface roughness;
- a data zone defined on the thin film magnetic disc and located outward from the landing zone, the data zone being adapted to magnetically record information via the air bearing read/write head, the data zone having a second surface roughness, wherein the second surface roughness has a roughness average Ra of at least 15 Angstroms;
- and
- a lubricant over both the landing zone and the data zone, wherein the lubricant is PFPE lubricant which has been fractionated to exclude fractions of high fractionation, wherein the lubricant has been fractionated to exclude fractions of greater than about 4000 a.m.u., and wherein the lubricant has also been fractionated to exclude fractions of less than about 1200 a.m.u.
A method of manufacturing a thin film magnetic disc for a computer disc drive, the computer disc drive having an air bearing read/write head mounted on an actuator arm adjacent a surface of the thin film magnetic disc, the method comprising:
- providing a thin magnetic disc adapted to magnetically record information via the air bearing read/write head;
- roughening a landing zone on the thin film magnetic disc with a roughness average Ra of greater than 100 Angstroms;
- roughening a data zone on the thin film magnetic disc outward from the landing zone, with a roughness average Ra of at least 15 Angstroms;
- fractionating PFPE lubricant into a first molecular weight fraction wherein the first molecular weight fraction includes molecular weights of less than about 1200 a.m.u., a second molecular weight fraction wherein the second molecular weight fraction includes molecular weights of between about 1200 a.m.u. and 4000 a.m.u., and a third molecular weight fraction wherein the third molecular weight fraction includes molecular weights of greater than about 4000 a.m.u.;
- and
- applying the second molecular weight fraction to the roughened landing zone and the roughened data zone.
A method of manufacturing a thin film magnetic disc for a computer disc drive, the computer disc drive having an air bearing read/write head mounted on an actuator arm adjacent a surface of the thin film magnetic disc, the method comprising:
- providing a thin film magnetic disc adapted to magnetically record information via the air bearing read/write head, the thin film magnetic disc having a landing zone and a data zone located outward from the landing zone;
- roughening the landing zone with a landing zone surface roughness which is rougher than a data zone surface roughness on the data zone;
- fractionating PFPE lubricant to exclude fractions of high molecular weight relative to molecular weights of the lubricant prior to fractionation and thereby form a fractionated lubricant;
- and
- applying the fractionated lubricant to the thin film magnetic disc both on the data zone and on the landing zone with the landing zone surface roughness which is rougher than the data zone surface roughness.
Dependencies are inferred from the claim text.