Inclined Etching Resist for PCB Positional Accuracy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing method for forming conductive patterns on a wiring circuit board using a subtractive etching process results in reduced positional accuracy of the outer shape of the conductive patterns due to uneven etching, leading to suboptimal electrical properties.
Innovation Solution
The method involves forming a wiring circuit board assembly sheet with a support sheet and inclined metal-based portions, where the etching resist pieces are also inclined relative to the conveyance direction, ensuring that both the first and second pieces are etched under the same conditions, maintaining positional accuracy and achieving desired electrical properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the conductive pattern is formed by a subtractive etching method with the etching resist parallel to the end edges, then the manufacturing process is simple, but the positional accuracy of the outer shape is reduced due to uneven etching
Solution Approach 1:
The patent applies asymmetry by inclining the front and rear pieces of the etching resist at specific angles (e.g., 45 degrees) relative to the end edges of the support sheet. This asymmetric configuration ensures that both pieces are inclined relative to the conveyance direction, allowing the etching solution to contact both pieces under substantially the same conditions. This resolves the technical contradiction by improving positional accuracy through asymmetric resist orientation while maintaining a relatively simple etching process.
2Manufacturing precision
If the etching resist pieces are parallel to the end edges, then the manufacturing process is straightforward, but the etching solution causes uneven etching with the front piece being etched more vigorously than the rear piece
Solution Approach 1:
The patent employs asymmetry by configuring the front and rear pieces of the etching resist to be inclined at specific angles relative to the end edges, rather than being parallel. This asymmetric arrangement ensures that both pieces present similar surfaces to the etching solution flow, achieving uniform etching conditions across all pieces. This resolves the contradiction by improving etching uniformity while the inclined configuration itself provides clear alignment guidance during manufacturing.
Solution Approach 2:
The patent changes the geometric parameters of the etching resist configuration by introducing specific inclination angles (e.g., 45 degrees) for the front and rear pieces relative to the end edges. This parameter change transforms the resist orientation from parallel to inclined, fundamentally altering how the etching solution interacts with the resist pieces. This resolves the technical contradiction by achieving uniform etching through modified geometric parameters while maintaining manufacturability.
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 ensures that the wiring circuit board assembly sheet has a metal-based portion with excellent positional accuracy of the outer shape, resulting in improved electrical properties and thermal conductivity.
Implementation Method 1
a metal-based sheet exposed from the etching resist is brought into contact with the etching solution discharged along the right-left direction, while the laminate progresses in the conveyance direction
Data Source
AI summary
A wiring circuit board assembly sheet includes a support sheet having two end edges parallel with each other and a plurality of wiring circuit boards disposed at spaced intervals to each other in the support sheet. The wiring circuit board includes a metal-based portion having a generally rectangular frame shape. The metal-based portion includes a first piece along a first direction perpendicular to a thickness direction of the support sheet, and a second piece along a second direction perpendicular to the thickness direction and the first direction. Both the first piece and the second piece are inclined with respect to the end edge of the support sheet.