Perpendicular Magnetic Head Side Shield Geometry for Write Performance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Magnetic heads for perpendicular magnetic recording face challenges in preventing unwanted erasure due to skew, particularly in achieving high recording densities and maintaining write characteristics, as conventional methods limit the cross-sectional area of the main pole near the medium facing surface, affecting magnetic flux passage and write performance.
Innovation Solution
The magnetic head design includes a main pole with two side shields, where the side shields' geometry allows for a larger cross-sectional area near the medium facing surface by adjusting the angles and positions of the sidewalls, and a manufacturing method that forms these shields and gap parts to enhance magnetic flux passage and write characteristics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the cross-sectional area of the main pole near the medium facing surface is increased, then magnetic flux passage and write characteristics are improved, but unwanted erasure due to skew increases
Solution Approach 1:
The side shields are divided into multiple sections along the track width direction, with each section having different widths at different positions. This segmentation allows the magnetic field to be controlled in different zones, preventing unwanted erasure while maintaining good write characteristics in the target track area.
Solution Approach 2:
The side shields have non-uniform width distribution along the track width direction, creating local variations in magnetic field confinement. The wider portions provide better field confinement to prevent erasure, while the narrower portions allow sufficient flux passage for write operations, achieving local optimization of both contradictory requirements.
2Manufacturing precision
If the track width is reduced to achieve higher recording densities, then recording density is improved, but write characteristics such as overwrite property deteriorate
Solution Approach 1:
The side shields extend in the vertical direction (height from medium facing surface) in addition to the track width direction. This adds a dimensional degree of freedom for controlling magnetic field distribution, allowing narrow track width for high density while maintaining adequate write characteristics through vertical field confinement.
Solution Approach 2:
The side shields have varying widths at different positions along the track width direction, creating localized magnetic field confinement zones. This allows the main pole to maintain a narrow overall width for high recording density while having enhanced field confinement in specific regions to preserve write characteristics.
3Reliability
If the neck height of the main pole is reduced to improve write characteristics, then overwrite property is improved, but structural stability and magnetic flux passage are affected
Solution Approach 1:
The side shields are segmented into multiple sections that can independently control magnetic field distribution at different heights. This segmentation allows the neck region to have reduced height for improved overwrite property while the lower sections provide structural support and flux passage, separating the conflicting requirements spatially.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This design effectively prevents unwanted erasure and improves write characteristics by increasing the cross-sectional area of the main pole, allowing more magnetic flux to pass through and enhancing recording density and overwrite properties.
Implementation Method 1
a coil configured to produce a magnetic field corresponding to data to be written on the recording medium
Implementation Method 2
The main pole is configured to allow a magnetic flux corresponding to the magnetic field produced by the coil to pass, and configured to produce a write magnetic field
Data Source
AI summary
A first side shield has a first sidewall and a second sidewall. A second side shield has a third sidewall and a fourth sidewall. The distance between the first sidewall and the third sidewall decreases with increasing proximity to the top surface of a substrate. The second and fourth sidewalls are close to perpendicular to the top surface of the substrate. Each of the second and fourth sidewalls has an edge farthest from the top surface of the substrate, the edge being parallel to the medium facing surface. The main pole has a first, a second, a third and a fourth side surface. The first side surface is opposed to the first sidewall. A portion of the second side surface is opposed to the second sidewall. The third side surface is opposed to the third sidewall. A portion of the fourth side surface is opposed to the fourth sidewall.