HAMR Medium Bilayer Structure for Reduced Laser Power
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Heat-assisted magnetic recording (HAMR) media with thermal-barrier layers (TBLs) face challenges in achieving high thermal gradients without increasing laser power, which can degrade recording performance and reduce HAMR head lifetime, and require costly and maintenance-intensive fabrication processes.
Innovation Solution
A bilayer structure comprising a seed layer and a thermal-transport-control layer (TTCL) with tailored thermal conductivity, reducing the heat-sink layer thickness by 40-50% and eliminating the need for an oxide-based TBL, while maintaining similar signal-to-noise ratio and laser power, and improving manufacturability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If a thermal-barrier layer (TBL) is used to achieve high thermal gradients, then thermal gradient is improved, but laser power must be increased which degrades recording performance and reduces HAMR head lifetime
Solution Approach 1:
The patent changes the thermal conductivity parameter of the layer between the heat-sink layer and magnetic-recording layer. By using a layer with specifically controlled thermal conductivity (higher than conventional TBLs but lower than heat-sink layers), the system achieves high thermal gradients without requiring increased laser power, thus resolving the contradiction between thermal gradient and laser power consumption
Solution Approach 2:
The patent employs a composite structure consisting of a heat-sink layer, a intermediate layer with controlled thermal conductivity, and a magnetic-recording layer. This composite design allows optimization of thermal transport properties to achieve high thermal gradients at reduced laser power, avoiding the degradation of recording performance and HAMR head lifetime
2Temperature
If a thermal-barrier layer (TBL) is used to achieve high thermal gradients, then thermal gradient is improved, but fabrication process becomes costly and maintenance-intensive
Solution Approach 1:
The patent changes the material composition and thermal conductivity parameters of the intermediate layer to achieve the desired thermal gradient effect. By selecting materials with appropriate thermal conductivity ranges and using depositable layer structures, the fabrication process becomes simpler and less costly compared to conventional oxide-based TBLs, while maintaining high thermal gradients
3Use of energy by moving object
If heat-sink layer thickness is reduced to lower laser power, then laser power is decreased, but thermal gradient is reduced which affects recording performance
Solution Approach 1:
The patent changes the thermal conductivity parameter of the intermediate layer to compensate for the reduced heat-sink layer thickness. By using a layer with optimized thermal conductivity, the system maintains high thermal gradients even with thinner heat-sink layers, allowing reduced laser power without sacrificing recording performance
Solution Approach 2:
The patent introduces an intermediate layer with controlled thermal conductivity between the heat-sink layer and magnetic-recording layer. This intermediary layer acts as a thermal bridge that efficiently transports heat from the heat-sink layer to the magnetic-recording layer, maintaining high thermal gradients even when the heat-sink layer is thin, thus enabling reduced laser power operation
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 bilayer structure efficiently dissipates heat, reduces media surface roughness, and allows for controlled laser power, enhancing recording performance and reliability while simplifying the manufacturing process.
Implementation Method 1
a thermal-transport-control layer (TTCL) with tailored thermal conductivity
Implementation Method 2
By heating the surface of the magnetic-recording medium with a laser spot during write operations
Implementation Method 3
coercivity of the magnetic-recording medium is reduced so that the magnetic field of the magnetic-recording head can record data
Data Source
AI summary
A heat-assisted magnetic recording (HAMR) medium includes a substrate, a bi-layer, a heat-sink layer, and a magnetic-recording layer. The bi-layer includes a seed layer disposed on the substrate, and a thermal-transport-control layer (TTCL) disposed on seed layer. The heat-sink layer is disposed on the TTCL; and the magnetic-recording layer is disposed on the heat-sink layer. The bi-layer is configured to enable use of a 50% thinner heat-sink layer that allows use of a reduced operating current of a laser in HAMR write operations while maintaining about the same write performance parameters as a HAMR medium that includes a thermal-barrier layer (TBL) and twice as thick heat-sink layer. A HAMR data-storage device that incorporates the HAMR medium within a HAMR disk, and a method for making the HAMR medium are also described.