Multiple microvia layers in semi-sequential build-up technique

摘要

The components of the future with high pin count will need multiple microvia layers and very fine lines for the purpose of maximum routing. These, however, cannot be produced economically on the basis of current HDI-technology.It is the objective of the project compound "HDI-Assembly" to develop a new HDI-generation, the so-called #mu#HDI-technology.Semi-sequential build-up techniques substantially improve upon sequential build-ups for the creation of multiple micro-via drill layers (>3 per side). Breaking down the multiple microvia build-up into several steps/partial build-ups allows a selective processing of sub-multilayers; this helps in reducing the costs caused by rejects, making the semi-sequential buildup the more cost-effective strategy, particularly when expensive multilayer cores are being involved.The semi-sequential build-up technology for multiple microvia layers, 50 #mu#m fine line conductors on microvia layers and the processing of appropriate materials are the challenging tasks of the #mu#HDI -technology.