Odd-Layer PCB via formation using simultaneous etching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing multi-layer printed circuit boards (PCBs) with even circuit layers are not suitable for portable electronic devices due to increased thickness, and the manufacturing process is complex, involving mechanical drilling or laser processes for via hole formation.
Innovation Solution
A method for manufacturing a printed circuit board with odd circuit layers using an etching process to simultaneously form vias and inner circuit layers, eliminating the need for plating and reducing manufacturing steps, while burying vias in insulating layers for improved heat dissipation and cost reduction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If even circuit layers are used in multi-layer PCB, then the manufacturing process is standardized, but the substrate thickness increases making it unsuitable for portable devices
Solution Approach 1:
The patent applies asymmetry by transitioning from the conventional even-numbered circuit layer structure to an odd-numbered circuit layer structure. This asymmetric change in layer configuration allows the PCB to achieve a thinner profile while maintaining manufacturing feasibility, directly addressing the contradiction between standardized manufacturing and reduced substrate thickness.
Solution Approach 2:
The patent inverts the conventional approach by forming vias and inner circuit layers simultaneously through an etching process rather than through sequential mechanical drilling or laser processes. This inversion of the manufacturing sequence simplifies the process and reduces the number of insulating layers needed, thereby reducing overall substrate thickness.
2Manufacturing precision
If mechanical drilling or laser process is used to form via holes, then via holes can be formed precisely, but the manufacturing process becomes complex and costly
Solution Approach 1:
The patent merges the via formation process with the inner circuit layer formation process into a single etching step. Instead of separately forming via holes and then depositing circuit patterns, the etching process simultaneously creates both the via holes and the inner circuit layers, significantly simplifying the manufacturing process while maintaining precision.
Solution Approach 2:
The patent replaces mechanical drilling or laser processes with a chemical etching process for forming via holes. This substitution eliminates the need for complex mechanical or thermal systems, reducing manufacturing complexity and cost while achieving precise via hole formation through controlled chemical reactions.
3Reliability
If plating method is used to form vias, then conductive vias can be formed reliably, but the manufacturing cost increases
Solution Approach 1:
The patent employs a cost-effective etching process instead of expensive plating methods to form conductive vias. By using a disposable etching approach that forms conductive pathways through the insulating layer without requiring complex plating equipment and materials, the manufacturing cost is significantly reduced while maintaining via conductivity reliability.
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 approach results in a lighter, slimmer PCB structure with enhanced heat dissipation and reduced manufacturing costs, as the etching process forms conductive vias and inner circuit layers without increasing the number of insulating layers, preventing substrate bending and simplifying the manufacturing process.
Implementation Method 1
an etching process, thereby forming the vias and the inner circuit layer simultaneously
Data Source
Figure 1~5
Figure 6~11
Figure 12~16
AI summary
Disclosed are a printed circuit board and a method for manufacturing the same. The printed circuit board includes a core insulating layer, at least one via formed through the core insulating layer, an inner circuit layer buried in the core insulating layer, and an outer circuit layer on a top surface or a bottom surface of the core insulating layer, wherein the via includes a first part, a second part below the first part, a third part between the first and second parts, and at least one barrier layer including a metal different from a metal of the first to third parts. The inner circuit layer and the via are simultaneously formed so that the process steps are reduced. Since odd circuit layers are provided, the printed circuit board has a light and slim structure.