As Europe's largest HF circuit board producer, KSG Leiterplatten GmbH processes around 25,000 sqm of base materials per year for the most diverse high frequency applications. Due to their many years of experience in this technology segment, KSG have been able to acquire a comprehensive technological know-how. In the on-going development work with our customers this treasure trove of knowledge and experience is constantly being expanded.
Materials in the frequency range up to 100 GHz consist mostly of PTFE (polytetrafluorethylene), ceramic fillers and a glass matting for stabilisation. The processing of these materials also requires, apart from matched production parameters for the mechanical processes, the deployment of specific process equipment (plasma) for chemical pre-treatment of the products.
The strengthening of ultra-high frequency signals is often associated with a significant power loss in the IC’s. This is where structure and connection technologies come in which provide for direct mounting of the bare chips on a buried copper carrier with simultaneous wire bonded contacting to the IC connection surfaces. For this reason we have developed, jointly with our customers, specific layer structures in a combination of ultra-high frequency capable materials and thick copper layers to spread the heat. The tolerance demands of +/- 15 µm required for the conductive pattern structures relevant for HF can be realised reliably by means of optimised production processes.
High frequency materials are well known to be more cost-intensive than standard base materials so these are only used on the necessary layers. This results in mixed structures composed of different materials for multiple layer circuits. The mix of copper, ceramic, fillers, glass and different resin systems determines a design-specific adaptation of the chemical and mechanical operating parameters. This is why we offer our customers support early on through our R&D department in order to be able to test at the design stage and to optimise a stable production flow cost-effectively.