PCB Faraday Wall Structure for RF Isolation Without Electroplating

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current PCB shielding techniques for RF signals involve costly and inefficient processes like electroplating through-holes and creating gaps, which can lead to leakage at high frequencies and unnecessary steps.

Innovation Solution

A copper Faraday wall is inserted into a trench on the PCB to form a continuous barrier, eliminating the need for electroplating and providing effective isolation between microwave circuits without chemical processing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If electroplating through-holes is used to create shielding fences, then RF mode attenuation is achieved, but manufacturing cost and process complexity increase significantly

Engineering Contradiction:
ImproveRF mode attenuationVSAvoidmanufacturing process complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent extracts the harmful electroplating process from the manufacturing workflow and replaces it with a mechanical insertion method. Through-holes are drilled and then filled with conductive material through insertion rather than chemical electroplating, eliminating the complex chemical processing steps while maintaining the shielding fence functionality for RF mode attenuation.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent replaces the chemical system (electroplating) with a mechanical system (drilling and insertion). Instead of using chemical processes to deposit conductive material through electroplating, the invention uses mechanical drilling to create holes and then mechanically inserts conductive material to form the shielding fence, simplifying the manufacturing process.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Reliability

If gaps are created within multi-layer PCBs for shielding, then RF isolation is improved, but structural integrity and manufacturing efficiency deteriorate

Engineering Contradiction:
ImproveRF isolationVSAvoidmanufacturing efficiency
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent applies preliminary action by pre-drilling through-holes in the PCB layers before assembly. The holes are created in advance at the correct positions and orientations, allowing for efficient subsequent insertion of conductive material. This preliminary preparation eliminates the need for complex post-assembly modifications and maintains manufacturing efficiency while achieving the required RF isolation through the inserted shielding structures.

Inventive Principle:
Principle #10Preliminary action

3Reliability

If through-holes are drilled and electroplated for shielding fences, then higher-order RF mode attenuation is achieved, but manufacturing cost increases

Engineering Contradiction:
Improvehigher-order RF mode attenuationVSAvoidmanufacturing cost
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The patent employs cheap conductive material inserts that are inserted into pre-drilled holes to form shielding fences. These inserts are simple, inexpensive components that can be easily manufactured and replaced if necessary. The approach avoids the expensive electroplating process while maintaining the effectiveness of the shielding fence for attenuating higher-order RF modes, significantly reducing manufacturing cost.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

4Reliability

If complex geometrical shapes with chamfered corners are used for Faraday walls, then isolation effectiveness is improved, but manufacturing precision requirements increase

Engineering Contradiction:
Improveisolation effectivenessVSAvoidgeometrical precision
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

The patent utilizes parameter changes by employing complex geometrical shapes with chamfered corners for the Faraday walls. The chamfered corners and specific geometric parameters are optimized to enhance the isolation effectiveness of the Faraday walls. By carefully selecting and adjusting these geometric parameters, the patent achieves improved isolation performance while managing the manufacturing precision requirements through standardized design features.

Inventive Principle:
Principle #35Parameter changes

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 copper Faraday wall effectively blocks electromagnetic radiation, acting as a tuning element and forming a barrier to isolate adjacent circuits, while allowing low-cost, high-volume fabrication without chemical processing.

Implementation Method 1

A copper Faraday wall is inserted into a trench on the PCB to form a continuous barrier, eliminating the need for electroplating and providing effective isolation between microwave circuits

Methodology Applied
Scientific EffectElectromagnetic shielding: Faraday Cage

Data Source

PatentEP4000357B1Wall for isolation enhancement
Publication Date: 2025.08.27 RAYTHEON CO
  • EP4000357B1 patent drawingFigure 1~2
  • EP4000357B1 patent drawingFigure 3~5
  • EP4000357B1 patent drawingFigure 6A~6D

AI summary

A circuit assembly is provided and includes a printed circuit board (PCB) having a circuit element region and defining a trench surrounding an entirety of the circuit element region, a circuit element disposed within the circuit element region of the PCB; and a Faraday wall. The Faraday wall includes a solid, unitary body having a same shape as the trench. The Faraday wall is disposed within the trench to surround an entirety of the circuit element.