Disk drive measuring fly height by applying a bias voltage to an electrically insulated write component of a head
View Patent ↗A disk drive is disclosed comprising a disk, and a slider comprising a head, where the head comprises a write component electrically insulated from the slider. A bias voltage is applied to the write component, and a current flowing between the write component and the disk is measured, wherein the current is indicative of a fly height of the head.
1. A disk drive comprising:
a disk;
a slider comprising a head, the head comprising a write component electrically insulated from the slider; and
control circuitry operable to:
apply a bias voltage to the write component; and
measure a current flowing between the write component and the disk, wherein the current is indicative of a fly height of the head.
2. The disk drive as recited in claim 1 , wherein the write component comprises a write pole.
3. The disk drive as recited in claim 2 , wherein the write pole is electrically insulated from a shield by an insulating layer.
4. The disk drive as recited in claim 1 , wherein:
the head comprises a laser operable to generate a light for heating the disk during a write operation; and
the write component comprises an optical component operable to focus the light onto the disk.
5. The disk drive as recited in claim 4 , wherein the optical component comprises a near field transducer.
6. The disk drive as recited in claim 5 , wherein the near field transducer is electrically insulated from a write pole by an insulating layer.
7. The disk drive as recited in claim 1 , wherein the write component comprises a write pad proximate a write pole.
8. The disk drive as recited in claim 1 , wherein:
the slider comprises an air bearing surface (ABS) proximate the disk;
a coating covers at least part of the ABS; and
the coating is modified proximate the write component to improve a conductivity of the write component relative to the disk.
9. The disk drive as recited in claim 8 , wherein a conductivity of the coating is increased proximate the write component.
10. The disk drive as recited in claim 8 , wherein the coating is at least partially depleted proximate the write component.
11. The disk drive as recited in claim 1 , wherein the bias voltage comprises a negative bias voltage.
12. The disk drive as recited in claim 1 , wherein:
the bias voltage is applied to the write component over a lead; and
the current flowing between the write component and the disk is measured by measuring the current flowing through the lead.
13. A method of operating a disk drive comprising a disk, and a slider comprising a head, the head comprising a write component electrically insulated from the slider, the method comprising:
applying a bias voltage to the write component; and
measuring a current flowing between the write component and the disk, wherein the current is indicative of a fly height of the head.
14. The method as recited in claim 13 , wherein the write component comprises a write pole.
15. The method as recited in claim 14 , wherein the write pole is electrically insulated from a shield by an insulating layer.
16. The method as recited in claim 13 , wherein:
the head comprises a laser operable to generate a light for heating the disk during a write operation; and
the write component comprises an optical component operable to focus the light onto the disk.
17. The method as recited in claim 16 , wherein the optical component comprises a near field transducer.
18. The method as recited in claim 17 , wherein the near field transducer is electrically insulated from a write pole by an insulating layer.
19. The method as recited in claim 13 , wherein the write component comprises a write pad proximate a write pole.
20. The method as recited in claim 13 , wherein:
the slider comprises an air bearing surface (ABS) proximate the disk;
a coating covers at least part of the ABS; and
the coating is modified proximate the write component to improve a conductivity of the write component relative to the disk.
21. The method as recited in claim 20 , wherein a conductivity of the coating is increased proximate the write component.
22. The method as recited in claim 20 , wherein the coating is at least partially depleted proximate the write component.
23. The method as recited in claim 13 , wherein the bias voltage comprises a negative bias voltage.
24. The method as recited in claim 13 , wherein:
the bias voltage is applied to the write component over a lead; and
the current flowing between the write component and the disk is measured by measuring the current flowing through the lead.