Magnetic Recording Transducer Sidewall Angle Profile

The patent applies local quality by varying the sidewall angle of the main pole at different positions along the down-track direction. The sidewall angle is made steeper (closer to perpendicular) at the air-bearing surface and progressively less steep toward the bottom, creating location-specific geometric properties that optimize magnetic field generation. This gradient in sidewall angle concentrates magnetic flux where needed and reduces fringing effects, thereby increasing write field magnitude without requiring complex manufacturing processes beyond standard semiconductor fabrication techniques.

The varying sidewall angle profile creates local variations in magnetic field gradient along the down-track direction. The steeper sidewalls at the air-bearing surface produce stronger magnetic field gradients, which are critical for high recording densities. This local optimization of field gradient is achieved through geometric design rather than adding complex magnetic shielding or multiple poles, maintaining relatively simple device structure while significantly improving magnetic field gradient performance.

The varying sidewall angle profile enhances cross-track magnetic anisotropy by creating localized magnetic field concentration at the air-bearing surface where the sidewalls are steepest. This geometric configuration naturally guides magnetic flux along the desired path and reduces leakage fields, thereby improving magnetic anisotropy. The approach uses purely geometric design rather than requiring complex magnetic materials or multiple fabrication steps, maintaining fabrication simplicity while improving reliability.

The varying sidewall angle profile helps prevent domain lockup by creating a more controlled magnetic field distribution. The steeper sidewalls at the air-bearing surface reduce fringe fields that can cause unwanted domain nucleation and lockup. The gradual transition in sidewall angle also helps manage magnetic flux continuity, reducing abrupt field changes that promote domain instability. These geometric modifications are achieved within standard fabrication processes, maintaining device simplicity while improving domain stability and reliability at high recording densities.