Slider deposits for control of pole-to-disc spacing
View Patent ↗A head for a disc drive and a method of making the head. The head includes a substrate with a trailing side and a first air bearing surface that generates lift. A magnetic transducer is deposited along the trailing side and has a pole tip that is spaced apart from a disc by a pole-to-disc spacing. The head also includes a deposit along the trailing side. The deposit includes a second air bearing surface that changes position relative to the first air bearing surface as temperature increases.
1. A head, comprising:
a substrate including a substrate surface and a substrate trailing side;
an overcoat layer positioned along the substrate trailing side;
a transducer positioned between the substrate and the overcoat layer and having a trailing edge; and
a first deposit positioned along the substrate trailing side at least partially past the trailing edge, the first deposit including a first temperature compensating bearing surface that changes position relative to the substrate surface as temperature increases, and at least a portion of the first deposit has a coefficient of temperature expansion that is greater than a coefficient of temperature expansion of the transducer.
2. The head of claim 1 wherein a tip of the transducer increasingly protrudes as temperature increases, and the first compensating bearing surface generates a temperature compensating lift that compensates for the protrusion.
3. The head of claim 2 wherein the temperature compensating lift stabilizes a tip-to-storage surface spacing.
4. The head of claim 1 wherein at least a portion of the first deposit has a coefficient of temperature expansion that is greater than a coefficient of temperature expansion of the substrate.
5. The head of claim 4 further comprising a second deposit that is positioned along the trailing side and has a coefficient of temperature, expansion that is more than a coefficient of temperature expansion of the substrate.
6. The head of claim 1 further comprising a second deposit that is positioned along the trailing side and has a coefficient of temperature expansion that is less than a coefficient of temperature expansion of the substrate.
7. The head of claim 6 wherein the second deposit has a height along the trailing side that differs from a height along the trailing side of the first deposit.
8. The head of claim 1 wherein at least a portion of the first deposit has a coefficient of temperature expansion that is greater than 12.2×10 −6 /degree Centigrade.
9. The head of claim 1 wherein at least a portion of the first deposit is formed of the same material as a pole tip of the transducer.
10. The head of claim 1 wherein at least a portion of the first deposit comprises copper.
11. The head of claim 1 wherein the first compensating bearing surface is coated with a diamond-like coating.
12. The head of claim 1 wherein the first deposit is partially embedded in a cavity formed in the substrate and partially protrudes past the trailing side of the substrate.
13. The head of claim 1 wherein the substrate has a top substrate surface opposite the substrate surface, and the first deposit extends up to the top substrate surface.
14. The head of claim 1 wherein the first deposit is positioned on the trailing side of the substrate.
15. The head of claim 10 wherein the first deposit is embedded in a cavity formed in the substrate.
16. The head of claim 10 wherein the first deposit is deposited on the transducer.
17. The head of claim 1 , further comprising:
an electric heating element that is deposited on the first deposit.
18. The head of claim 1 , wherein the first deposit is shaped to form a trench in the substrate.
19. A head, comprising:
a substrate including a substrate trailing side, and a substrate surface that forms a part of a bearing surface;
an overcoat layer positioned along the substrate trailing side;
a transducer positioned between the substrate and the overcoat layer and having a trailing edge; and
a first deposit positioned along the substrate trailing side and extending past a portion of the transducer toward the trailing edge, the first deposit including a temperature compensating deposit surface that changes position relative to the substrate surface as temperature increases and at least a portion of the first deposit has a coefficient of temperature expansion that is greater than a coefficient of temperature expansion of the transducer, and further wherein the temperature compensating deposit surface forms a part of the bearing surface.
20. The head of claim 19 wherein the first deposit is metallic.
21. The head of claim 20 wherein the metallic deposit increases lift in a high pressure region of the bearing surface.
22. The head of claim 20 where the metallic deposit decreases suction in a low pressure region of the bearing surface.
23. The head of claim 20 wherein the metallic deposit comprises copper.
24. The head of claim 19 wherein a tip of the transducer increasingly protrudes as temperature increases and the deposit surface generates a temperature compensating lift.
25. The head of claim 19 wherein the deposit surface generates a temperature compensating lift that stabilizes a tip-to-storage surface spacing.
26. The head of claim 19 wherein the first deposit that has a coefficient of temperature expansion that is greater than a coefficient of temperature expansion of the substrate.
27. The head of claim 26 and further comprising a second deposit that is deposited along the trailing side and has a coefficient of temperature expansion that is more than a coefficient of temperature expansion of the substrate.
28. The head of claim 26 wherein at least a portion of the first deposit is formed of the same material as a pole tip of the transducer.
29. The head of claim 26 wherein at least a portion of the first deposit comprises copper.
30. The head of claim 26 wherein the compensating deposit surface includes a diamond-like coating.