Air Gap Corrections in Clamped Stripline in Plane Permittivity Extraction
Air gap corrections eliminate systematic two to six percent dielectric underestimation in clamped stripline tests, preventing finished board impedance failures.
Laminate Qualification
Material Verification
Systematic testing of raw circuit board substrates ensures they meet the electrical and mechanical requirements for a specific manufacturing process. The laminate qualification involves measuring the glass transition temperature and the decomposition temperature to verify thermal stability. These benchmarks determine if the material can withstand the heat of lead free assembly without delaminating.
Quality engineers review the data sheets and perform independent lab tests to confirm compliance with industry standards.
Testing Protocol
Electrical properties such as the dielectric constant and the dissipation factor are measured across a range of frequencies. During laminate qualification, the material is subjected to high humidity and temperature to check for changes in insulation resistance. This step is necessary to ensure the reliability of the board in different operating environments.
Peel strength tests are also conducted to verify that the copper foil remains securely bonded to the dielectric after multiple thermal cycles.
Industrial Compliance
Documentation of the test results provides a baseline for the acceptance of production batches from the material supplier. Successful laminate qualification allows a manufacturer to add a specific substrate to their approved vendor list for high reliability projects. This process reduces the risk of field failures by screening out materials that do not meet the performance criteria.
Final approval is granted only after the material passes all the environmental and mechanical stress tests defined in the procurement specification.