Flexure Wiring Rigidity Control via Localized Insulating Layer Thickness
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing flexures in hard disk drives face challenges in reducing the rigidity contribution ratio of the wiring part, which is essential for maintaining a low flying height and stability of the slider, as previous methods either fail to control the rigidity effectively or compromise the dielectric strength voltage.
Innovation Solution
A flexure design featuring a metal substrate with a wiring part that includes a normal wiring part on the substrate and an aerial wiring part separated from the substrate, where the base insulating layer of the aerial wiring part is thinned to reduce rigidity and rigidity contribution ratio, while maintaining the required dielectric strength voltage for the normal wiring part.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If the metal substrate is thinned to control rigidity around the tongue, then the rigidity control is improved, but the wiring part's rigidity contribution ratio increases making it difficult to control overall rigidity
Solution Approach 1:
The patent applies local quality by making the base insulating layer thickness non-uniform: it is thinner at the aerial wiring part (0.5-2.0 μm) and thicker at the normal wiring part (2.0-5.0 μm). This localized variation allows the aerial wiring part to contribute less rigidity while the normal wiring part maintains sufficient dielectric strength, thereby controlling the overall rigidity contribution ratio of the wiring part.
2Stability of the object's composition
If the base insulating layer is thinned to reduce wiring part rigidity, then the rigidity contribution ratio is reduced, but the dielectric strength voltage may be compromised
Solution Approach 1:
The patent resolves this contradiction by applying different base insulating layer thicknesses to different functional regions: the aerial wiring part has a thinner base insulating layer (0.5-2.0 μm) to reduce rigidity contribution, while the normal wiring part has a thicker base insulating layer (2.0-5.0 μm) to ensure sufficient dielectric strength voltage. This localized differentiation allows both requirements to be satisfied simultaneously.
3Productivity
If the flying height is minimized to increase recording density, then the recording density is improved, but the stability of the minimized flying height becomes difficult to maintain
Solution Approach 1:
The patent applies parameter changes by modifying the base insulating layer thickness parameter in the aerial wiring part to be thinner (0.5-2.0 μm), which reduces the rigidity contribution ratio of the wiring part. This allows the metal substrate's rigidity to dominate, providing stable support for the slider at minimized flying height (5-20 nm), thereby maintaining stability while enabling high recording density.
Data Source
AI summary
A flexure includes a metal substrate whose front end supports a slider and a wiring part having a base insulating layer and a conductor layer formed on the base insulating layer. The wiring part includes a normal wiring part that is on the metal substrate and an aerial wiring part that is on a space separated from the metal substrate. The base insulating layer of the aerial wiring part is formed to be thinner than that of the normal wiring part. This configuration reduces a rigidity contribution ratio of the wiring part.