Ring-Shaped Substrate Film Formation via Gas Spraying
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for forming films on ring-shaped objects, such as glass spacers in hard disk drive devices, face challenges in achieving uniform film thickness and productivity due to issues with film formation on areas in contact with holding members, leading to exposed surfaces and increased manufacturing costs.
Innovation Solution
A method involving spraying a gas containing a coating raw material onto a ring-shaped substrate placed on a heated plate, allowing the substrate to float and land multiple times to form a conductive film on its entire surface, with controlled spray pressure and positioning to ensure uniformity and prevent exposure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If PVD or CVD methods are used to form a conductive ceramic film on glass spacers, then static electricity dissipation is improved, but film formation on contact surfaces with holding members is prevented, leading to exposed surfaces
Solution Approach 1:
Instead of attempting to coat the holding member contact areas (which blocks film formation), the patent inverts the approach by coating the entire spacer surface first, then selectively removing film only from the holding member contact areas through etching. This ensures complete film coverage on functional surfaces while exposing holding member contact areas.
Solution Approach 2:
The patent applies different treatments to different areas of the spacer: the functional surfaces (inner circumferential surface and magnetic disk contact surface) receive conductive ceramic film coating for static electricity dissipation, while the holding member contact surfaces are kept exposed through selective etching. This local differentiation resolves the contradiction between complete film coverage and holding member contact requirements.
2Manufacturing precision
If secondary film formation is performed after removing the spacer to eliminate exposed portions, then film coverage is improved, but manufacturing complexity and cost increase
Solution Approach 1:
The patent performs preliminary film formation on the entire spacer surface before mounting, ensuring complete coverage. Then, etching is performed as a preliminary preparation step before final assembly, creating the necessary exposed areas. This preliminary action approach consolidates multiple steps into a streamlined process.
Solution Approach 2:
The patent merges the film formation and holding member contact area preparation into a single integrated process sequence: coat entire surface → mount spacer → etch contact areas. This combines what would otherwise require separate film formation operations into one efficient workflow, reducing manufacturing complexity.
3Stability of the object's composition
If glass spacers are used instead of metal spacers to match thermal expansion coefficients, then thermal compatibility is improved, but static electricity accumulation increases due to insulator properties
Solution Approach 1:
The patent creates a composite structure by coating the glass spacer surface with a conductive ceramic film (such as silicon oxide or silicon nitride). This composite combines the thermal expansion compatibility of glass with the electrical conductivity of the ceramic film, simultaneously achieving thermal stability and static electricity dissipation.
Solution Approach 2:
The patent changes the electrical parameter (conductivity) of the glass spacer surface by applying a conductive ceramic coating. This parameter change transforms the insulator properties of glass into conductor properties where needed, while maintaining the original glass substrate's thermal expansion characteristics.
4Reliability
If a conductive ceramic film is applied to glass spacers to dissipate static electricity, then electrical conductivity is improved, but film thickness uniformity deteriorates due to conventional coating methods
Solution Approach 1:
The patent replaces mechanical contact-based coating methods (which cause uneven thickness) with vapor-phase deposition methods (PVD or CVD). These vapor-based processes deposit film uniformly across the spacer surface by allowing vapor to conformally coat all surfaces, including complex geometries, without mechanical contact.
Solution Approach 2:
The patent uses vapor-phase intermediaries (coating materials in vapor form) to transfer the conductive ceramic material onto the glass spacer surface. This intermediary approach allows uniform film deposition by enabling the coating material to reach all surfaces evenly through vapor diffusion and condensation, avoiding the thickness variations caused by direct mechanical contact.
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 enhances productivity while maintaining uniform film thickness across the ring-shaped object, reducing the likelihood of static electricity accumulation and preventing dust emission, thus improving the performance and reliability of hard disk drive components.
Implementation Method 1
a plate on which a ring-shaped substrate is placed
Implementation Method 2
spraying a gas containing a coating raw material toward a center hole of the ring-shaped substrate from above the ring-shaped substrate placed on the plate to cause the ring-shaped substrate to float up from the plate and form a film on a surface of the ring-shaped substrate
Data Source
AI summary
A method for producing a ring-shaped object includes: placing a ring-shaped substrate on a plate; and spraying a gas containing a coating raw material toward a center hole of the ring-shaped substrate from above the ring-shaped substrate placed on the plate to cause the ring-shaped substrate to float up from the plate and form a film on a surface of the ring-shaped substrate.