Transducer Head NFT-to-Pole Spacing Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing transducer heads for thermally assisted magnetic recording (HAMR) face challenges in precisely controlling the NFT-to-pole spacing (NPS) during manufacturing, which affects the thermal stability and recording density of magnetic storage media.
Innovation Solution
The method involves depositing a spacer layer on the NFT layer, forming an etch stop layer, and depositing a cladding layer, followed by milling at a sloped angle to control the NPS, using advanced lithography and etching processes to ensure precise positioning and uniformity of the NPS at the air-bearing surface.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional manufacturing processes are used for transducer heads, then manufacturing simplicity is maintained, but NFT-to-pole spacing precision deteriorates
Solution Approach 1:
The method performs preliminary actions by depositing the spacer layer and etch stop layer before final cladding deposition, establishing precise spacing geometry early in the process. The sloped milling is performed on the cladding layer after deposition, allowing the NPS to be controlled by the pre-established spacer layer rather than requiring complex direct spacing mechanisms.
Solution Approach 2:
The spacer layer serves as an intermediary element between the NFT layer and the cladding layer, physically defining the NFT-to-pole spacing. The etch stop layer acts as an intermediary that controls the milling depth, ensuring the sloped mill stops at the correct position to maintain precise spacing while simplifying the overall manufacturing approach.
2Manufacturing precision
If sloped angle milling is used to control NPS, then spacing precision is improved, but manufacturing complexity increases
Solution Approach 1:
The method changes the milling parameter by introducing a sloped angle rather than vertical milling. This parameter change allows the mill to naturally follow the slope of the etch stop layer interface, achieving uniform NPS across the air-bearing surface while using standard milling equipment. The sloped angle transforms a potentially complex precision spacing problem into a simpler geometric follow-along process.
3Measurement precision
If multiple layers are deposited for spacing control, then NPS accuracy is improved, but manufacturing steps increase
Solution Approach 1:
The method merges multiple functions into the cladding layer deposition step. The cladding layer is deposited over both the spacer layer and etch stop layer, combining the spacing definition and the milling stop functions into a single continuous layer. This integration reduces the number of separate manufacturing steps while maintaining precise spacing control through the underlying spacer and etch stop layers.
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 approach allows for accurate control of the NFT-to-pole spacing, enhancing thermal stability and recording density in HAMR systems by maintaining consistent spacing during the manufacturing process.
Implementation Method 1
depositing a spacer layer on an NFT layer of the transducer head
Implementation Method 2
forming an etch stop layer on a spacer layer of a transducer
Implementation Method 3
depositing a cladding layer on the etch stop layer
Implementation Method 4
milling the cladding layer at a sloped angle such that the milling stops at the etch stop layer
Data Source
AI summary
A method of making a transducer head disclosed herein includes depositing a spacer layer on an NFT layer of the transducer head, forming an etch stop layer on a spacer layer of a transducer, depositing a cladding layer on the etch stop layer, and milling the cladding layer at a sloped angle such that the milling stops at the etch stop layer.