Gradient write gap for perpendicular magnetic recording writer
View Patent ↗The present disclosure provides for a magnetic writer pole for use in a hard drive. The magnetic writer pole comprises a first bevel formed by a non-magnetic layer, the first bevel formed at a first angle and extending to a first throat height. The magnetic writer pole further comprises a second bevel formed by the non-magnetic layer and extending distally from the first bevel at a second angle that is greater than the first angle and extending to a second throat height. The magnetic writer pole further comprises a third bevel formed by the non-magnetic layer and extending distally from the second bevel at a third angle that is greater than the second angle.
1. A magnetic writer pole comprising:
an air-bearing surface;
a main pole defining and extending from a first portion of the air-bearing surface;
a trailing shield defining and extending from a second portion of the air-bearing surface; and
a non-magnetic layer disposed between the trailing shield and the main pole,
wherein the non-magnetic layer and the main pole define a contacting surface between the non-magnetic layer and the main pole,
and further wherein the contacting surface comprises:
a first bevel at a first angle relative to a transverse plane perpendicular to the air-bearing surface and extending to a first throat height;
a second bevel extending distally from the first bevel at a second angle relative to the transverse plane that is greater than the first angle and extending to a second throat height; and
a third bevel extending distally from the second bevel at a third angle relative to the transverse plane that is greater than the second angle.
2. The magnetic writer pole of claim 1 , wherein the first angle is between 10 and 40 degrees, the second angle is between 11 and 60 degrees, and the third angle is between 12 and 90 degrees.
3. The magnetic writer pole of claim 2 , wherein the first angle is between 20 and 40 degrees, the second angle is between 30 and 60 degrees, and the third angle is between 50 and 90 degrees.
4. The magnetic writer pole of claim 1 , wherein the first throat height is shorter than the second throat height.
5. The magnetic writer pole of claim 4 , wherein the second bevel is formed using ion milling.
6. A hard drive comprising:
a magnetic writer pole having
an air-bearing surface;
a main pole defining and extending from a first portion of the air-bearing surface;
a trailing shield defining and extending from a second portion of the air-bearing surface; and
a non-magnetic layer disposed between the trailing shield and the main pole,
wherein the non-magnetic layer and the main pole define a contacting surface between the non-magnetic layer and the main pole,
and further wherein the contacting surface comprises:
a first bevel at a first angle relative to a transverse plane perpendicular to the air-bearing surface and extending to a first throat height;
a second bevel extending distally from the first bevel at a second angle relative to the transverse plane that is greater than the first angle and extending to a second throat height; and
a third bevel extending distally from the second bevel at a third angle relative to the transverse plane that is greater than the second angle.
7. The hard drive of claim 6 , wherein the first angle is between 10 and 40 degrees, the second angle is between 11 and 60 degrees, and the third angle is between 12 and 90 degrees.
8. The hard drive of claim 6 , wherein the first throat height is shorter than the second throat height.
9. The hard drive of claim 6 , wherein the second bevel is formed using ion milling.