Removable Layer PCB Thermal Via Formation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for improving thermal conductivity in printed circuit boards, such as thermal vias and pre-fabricated copper coins, are labor-intensive, costly, and inadequate for high-power applications, with limitations in reducing thermal resistance and providing electrical connections.
Innovation Solution
A method using removable conductive layers and a horizontal plating system to form thermal and electrical paths by milling or laser drilling cavities in PCBs and filling them with conductive materials, which reduces thermal resistance and improves electrical connectivity without the drawbacks of traditional methods.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If thermal vias (PTHs) are added around power dissipating components, then thermal conductivity is improved, but manufacturing complexity and cost increase due to multiple drilling and plating operations
Solution Approach 1:
The patent combines multiple manufacturing operations (drilling, plating, filling) into a single integrated process. The removable layer is applied to the PCB surface, and all thermal via operations are performed through this layer simultaneously, merging sequential complex operations into one streamlined process that reduces manufacturing steps and complexity.
Solution Approach 2:
The removable layer serves as an intermediary tool that facilitates the manufacturing process. It acts as a temporary mask and support structure during drilling and plating operations, enabling precise thermal via creation without requiring multiple separate operations. After the process, the removable layer is discarded, having served its mediating function.
2Temperature
If pre-fabricated copper coins are inserted into PCB to improve thermal path, then thermal resistance is reduced, but labor intensity and manufacturing cost increase significantly
Solution Approach 1:
The patent employs a self-service manufacturing approach where the PCB structure itself creates the thermal pathways through automated drilling and plating operations. The removable layer enables the PCB to form its own thermal vias without requiring manual insertion of pre-fabricated copper coins, eliminating labor-intensive processes while achieving the same thermal management goal.
Solution Approach 2:
The patent replaces the mechanical manual process of inserting copper coins with an automated electrochemical plating process. Instead of physically inserting pre-fabricated elements, the system uses electroplating to deposit copper directly into drilled cavities through the removable layer, substituting manual mechanical operations with automated electrochemical processes.
3Ease of manufacture
If standard minimum distance between PTHs is maintained (one drill diameter), then manufacturing is simplified, but thermal resistance remains high for high-power applications
Solution Approach 1:
The patent changes the critical parameter of via spacing by enabling placement of thermal vias at distances less than one drill diameter. The removable layer provides structural support and precise positioning that allows closer via spacing without compromising manufacturing quality, thereby changing the spacing parameter from the conventional minimum to a reduced value that improves thermal conductivity.
Solution Approach 2:
The removable layer is applied in advance to the PCB surface before drilling operations. This preliminary action provides a protective and guiding layer that enables precise positioning of thermal vias at reduced spacing. The pre-applied layer ensures that even closely spaced vias can be manufactured with appropriate precision and structural integrity.
4Temperature
If inserted coins are used to improve thermal path, then thermal conduction is enhanced, but electrical ground connection is limited or nonexistent
Solution Approach 1:
The patent creates thermal vias that serve dual functions: thermal conduction and electrical grounding. The same plated through-holes that provide thermal pathways also establish electrical connections to ground planes on the PCB. This multi-functional approach eliminates the need for separate electrical connection structures, as the thermal via structure inherently provides both thermal and electrical functions.
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 reduces thermal resistance, lowers manufacturing costs, and enhances electrical connections, making it suitable for high-power applications while maintaining a stable and efficient thermal management system.
Implementation Method 1
removing the first and second removable layers from the PCB to form the PCB with a thermal and/or an electrical path
Implementation Method 2
panel plating the first side with a second metal to fill the first cavity and the second side with the second metal to fill the second cavity
Implementation Method 3
The first cavity is in a thermal communication with the second cavity... to form a thermal path including thermal cavities
Data Source
AI summary
A method for forming a thermal and electrical path in a PCB may include forming a first removable layer over a top surface of a PCB and a second removable layer over a bottom surface of the PCB. The method may also include milling or laser drilling the PCB from the top surface to form a first cavity extending into the PCB, plating the first side panel plating the first side with a second metal to partially fill the first cavity; and milling or laser drilling from the bottom surface to form a second cavity extending into the PCB, the first cavity in a thermal communication and/or an electrical communication with the second cavity. The method may also include panel plating the first side with a second metal to fill the first cavity and the second side with the second metal to fill the second cavity, and removing the first and second removable layers from the PCB to form the PCB with a thermal and/or an electrical path comprising the first cavity and the second cavity filled with the second metal.