'Bridging the Gap' - Technical Capabilities of a Direct Plate PTH Process

摘要

In contrast to electroless copper, direct metallization processes are inherently less expensive to operate, more environmental friendly, requires less floor space and are more efficient. Among the three common direct metallization methods, namely carbon based, conductive polymer based and palladium based, carbon based is the most attractive option, with the lowest cost and 'greenest' ingredients. However, despite past predictions to the contrary, electroless copper processes are still the most widely accepted through-hole metallization technologies in today's market. In their infancies, implementation of direct plate processes at PWB manufacturers produced panels of questionable reliability. This led many major OEMs to write specifications refusing to accept any alternatives to conventional electroless copper for through-hole metallization in PWB fabrication. However, despite the lack of official acceptance by certain OEMs, carbon-based direct metallization is widely used by PWB fabricators where lower costs and environmental concerns are the industries major drivers. This paper, focusing on higher technology applications, provides PWB fabricators and OEMs with current up to date comprehensive data on improvements made to the technical capabilities and reliability of this unique carbon-based direct metallization system. Additionally, the data supports the acceptance of this direct metallization technology as a viable alternative to conventional electroless copper processes.