Technical Requirements of Aluminum Circuits

Introduction

Aluminum printed circuit boards (PCBs) are essential in various electronics applications, yet there is no international standard governing their production. Currently, the Shenzhen PCB Association is drafting the electronics industry standards, specifically focusing on the "Flame Retardant Aluminum Laminate Specification."

Main Technical Requirements

1. Size Requirements

Board Size and Deviation: Specifications on the acceptable dimensions and permissible deviations.

Thickness and Tolerances: Defined thickness ranges and tolerances for aluminum PCBs.

Warpage Rate: Acceptable warpage limits to ensure the flatness of the boards.

2. Cosmetic Appearance

Cracks: No visible cracks are allowed.

Scratches and Burrs: Boards must be free from significant scratches and burrs.

Delamination: No delamination should be present.

Oxide Film Requirements: Consistent and controlled oxide film on the surface.

3. Functional Requirements

Peel Strength: Minimum peel strength to ensure layer adhesion.

Surface Resistivity: Specific resistivity values to ensure proper electrical performance.

Minimum Breakdown Voltage: Defined voltage threshold for dielectric breakdown.

Dielectric Constant: Specific dielectric constant values for reliable insulation.

Thermal Resistance: Requirements for heat dissipation capabilities.

Flammability: Compliance with flammability standards to ensure safety.

Aluminum CCL Inspection Methods

1. Dielectric Constant and Dielectric Loss Factor Measurement

Series Resonance Method: The variable Q value series resonance method is used. The sample, connected with a tuning capacitor, is part of a high-frequency circuit. The Q value is recorded to measure the dielectric properties.

2. Thermal Resistance Measurement

Temperature Difference Measurement: Measure the temperature difference and thermal conductivity at various points to calculate thermal resistance.

Conclusion

Aluminum PCBs are critical in modern electronics, and adherence to technical requirements ensures their reliability and performance. As standards evolve, maintaining rigorous inspection and measurement methods will be essential.