Polyimide and BeO mini port card performance comparison for CDF Run IIb

The new silicon detector design for CDF relies on advanced packaging solutions in order to attain the strict small size and low mass requirements dictated by the experiment´s physics program. The silicon strip detector at CDF is composed of overlaying silicon sensors in the form of a barrel around the colliding beam. The electronic instrumentation (sensors, readout and transceiver chips) is assembled into the staves of this barrel. In this paper we describe the development of the mini port card (MPC). The MPC is located at one of the ends of the stave, and it is responsible for signal translation and repetition from the readout chips to and from the data acquisition system (DAQ). The MPC´s development has taken two approaches that use different technologies. One of the approaches uses BeO as the board substrate (BeO-MPC), while the other approach uses a hybrid rigid-flexible polyimide substrate (Poly-MPC). We present test results of pre-production parts, each one assembled with a different MPC packaging technology. Complete thermal and electrical characterization of the MPC is shown, and the advantages and disadvantages of both technologies, as well as their influence in the overall system performance, are presented.