Wideband RF interconnects for organic chip packages comparison of single ended and differential transitions

Embedding of semiconductor chips into organic substrates allows a cheap and high degree of miniaturization. For RF applications the connection between chip and package is as important as the connection between package and baseboard. This paper presents both single ended and differential transitions for RF packages with special reference to what should be considered when using organic printed circuit boards (PCBs). Because of the fully impedance controlled design process the presented transitions can be used from DC to 60 GHz and guarantee best signal integrity. In addition a fast and flexible measurement of the package - baseboard transition is shown by the use of a specific contact structure. Moreover it is figured out how the discontinuities of the interconnect structure of the chip package can be localized in detail using TDR measurements.