Magnetic Head Layering for Spin Torque Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current magnetic recording technologies face challenges in increasing recording density while maintaining efficient recording magnetic fields and reducing gap magnetic fields, which affects the reliability and operating current density of magnetic heads.
Innovation Solution
The magnetic head design incorporates multiple magnetic and nonmagnetic layers, including Cu, Ag, Au, Al, Ti, Ta, Pt, Ir, W, Mo, Cr, Tb, Rh, Pd, and Ru, with specific thicknesses and configurations to control spin torque and oscillation frequencies, allowing for independent adjustment of recording and gap magnetic fields.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple magnetic and nonmagnetic layers are added to control spin torque and oscillation frequencies, then recording density and reliability are improved, but device complexity increases
Solution Approach 1:
The magnetic head is segmented into multiple functional layers including shield, magnetic pole, and three magnetic layers (first, second, third) separated by nonmagnetic layers. Each layer serves a specific function in controlling magnetic fields and spin torque, allowing independent optimization of recording and gap magnetic fields while maintaining overall system reliability
Solution Approach 2:
The patent implements a nested structure where magnetic layers are positioned between the shield and magnetic pole, with nonmagnetic layers interspersed between magnetic layers. This nested arrangement allows multiple functional layers to be integrated within a compact space, managing complexity through organized hierarchical structure
2Use of energy by moving object
If multiple magnetic and nonmagnetic layers with specific thicknesses are used to control spin torque, then operating current density is reduced, but manufacturing precision requirements increase
Solution Approach 1:
The patent specifies precise thickness parameters for each layer: second and fourth nonmagnetic layers are 1-3 nm thick, while first, third, and fifth nonmagnetic layers are 3-10 nm thick. These parameter optimizations control spin torque efficiency and reduce operating current density. The magnetic layers have specifically controlled thicknesses to achieve desired magnetic field characteristics
Solution Approach 2:
Different nonmagnetic layers are assigned different thickness ranges based on their specific functions: thinner layers (1-3 nm) for spin torque control interfaces, medium layers (3-10 nm) for magnetic field management. This local quality differentiation optimizes performance while managing manufacturing precision requirements through functional zoning
3Productivity
If magnetic layers are positioned between shield and magnetic pole to independently adjust magnetic fields, then recording density is enhanced, but device complexity increases
Solution Approach 1:
The magnetic field control is segmented into independent zones: the shield, magnetic pole, and three magnetic layers (first, second, third) positioned between them. This segmentation allows independent adjustment of recording magnetic field strength and gap magnetic field reduction, enabling enhanced recording density through optimized field distribution
Solution Approach 2:
The patent introduces an additional dimensional layering approach by positioning magnetic layers in the thickness direction between the shield and magnetic pole, rather than only in the planar direction. This vertical stacking enables independent magnetic field control in multiple dimensions, enhancing recording density through three-dimensional field optimization
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 enhances recording density, reduces operating current density, and improves reliability by efficiently applying magnetic fields to the recording medium, enabling stable and high-frequency oscillations.
Implementation Method 1
control spin torque and oscillation frequencies
Implementation Method 2
efficiently applying magnetic fields to the recording medium
Data Source
AI summary
According to one embodiment, a magnetic head includes a shield, a magnetic pole, a first magnetic layer provided between the shield and the magnetic pole, a second magnetic layer provided between the first magnetic layer and the magnetic pole, a third magnetic layer provided between the second magnetic layer and the magnetic pole, a first nonmagnetic layer provided between the shield and the first magnetic layer, a second nonmagnetic layer provided between the first magnetic layer and the second magnetic layer, a third nonmagnetic layer provided between the second magnetic layer and the third magnetic layer, and a fourth nonmagnetic layer provided between the third magnetic layer and the magnetic pole. The first and third nonmagnetic layers include one of Cu, Ag, Au, Al, and Ti. The second and fourth nonmagnetic layers include one of Ta, Pt, Ir, W, Mo, Cr, Tb, Rh, Pd, and Ru.