L10 Magnetic Recording Medium With h-BN Grain Boundaries
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing magnetic recording media face challenges in maintaining a stable granular structure and improving surface recording density due to issues with grain diameter and anisotropy of magnetic grains, particularly when using hexagonal boron nitride as a grain boundary portion.
Innovation Solution
A magnetic recording medium is designed with a two-layer structure, where the first magnetic layer includes magnetic grains with a L10 structure, and the second magnetic layer has a granular structure with hexagonal boron nitride at the grain boundary, and the (111) plane of the first magnetic layer is covered with boron nitride to facilitate epitaxial growth, maintaining a columnar crystal structure and reducing grain diameter.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If magnetic grains with high magnetocrystalline anisotropy constant are used to increase coercivity, then thermal stability is maintained, but grain diameter cannot be sufficiently reduced to improve surface recording density
Solution Approach 1:
The magnetic layer is divided into multiple sub-layers (first magnetic layer and second magnetic layer) with different grain size characteristics. The first magnetic layer contains magnetic grains with high magnetocrystalline anisotropy constant for thermal stability, while the second magnetic layer contains finer magnetic grains for high surface recording density. This segmentation allows each layer to optimize for its specific function without compromising the other.
Solution Approach 2:
Different regions of the magnetic recording medium are assigned different grain size and anisotropy characteristics. The first magnetic layer uses coarser grains with high anisotropy constant for thermal stability, while the second magnetic layer uses finer grains for high surface recording density. This local differentiation enables simultaneous optimization of thermal stability and surface recording density across the entire medium.
2Stability of the object's composition
If hexagonal boron nitride is used as grain boundary portion to stabilize granular structure, then manufacturing complexity increases, but granular structure stability is improved
Solution Approach 1:
Hexagonal boron nitride is introduced as a grain boundary portion during the film formation process to pre-establish stable grain boundaries before subsequent processing steps. This preliminary action ensures that the granular structure remains stable throughout manufacturing and operation, preventing grain growth and structural degradation without requiring complex post-processing.
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
The solution stabilizes the granular structure, allowing for further improvement in surface recording density and enabling a magnetic storage apparatus with high recording capacity.
Implementation Method 1
the magnetic grains included in the second magnetic layer are epitaxially grown from a (001) plane of the magnetic grains included in the first magnetic layer
Data Source
AI summary
A magnetic recording medium includes a substrate, an underlayer, a first magnetic layer, and a second magnetic layer in this order. The first magnetic layer includes magnetic grains having a L10 structure, and the second magnetic layer has a granular structure including magnetic grains having a L10 structure, and a grain boundary portion including hexagonal boron nitride. A (111) plane of the magnetic grains included in the first magnetic layer is covered with boron nitride at an interface with the second magnetic layer. The magnetic grains included in the second magnetic layer are epitaxially grown from a (001) plane of the magnetic grains included in the first magnetic layer. The magnetic grains included in the first magnetic layer and the magnetic grains included in the second magnetic layer are columnar crystals penetrating the first magnetic layer and the second magnetic layer, respectively.