High density interconnect multi-chip module for the front-end electronics of the PHENIX/MVD

A multi-chip module (MCM) based on High Density Interconnect (HDI) technology was developed for the front-end electronics of a high energy nuclear physics experiment to process charge pulses from silicon detectors. Stringent requirements in performance as well as low radiation length and minimum physical size of the module dictated the use of the most sophisticated MCM technology available. The module handles 256 input channels on an alumina substrate with milled cavities for die placements and four layers of thin-film traces of 42u width. A total of 20 custom integrated circuit chips and 98 passive components are assembled on a substrate of size 43 mm/spl times/48 mm. Various aspects of development efforts for the design and fabrication as well as the electrical test results of the module are discussed.