Improving of High-Speed Modules by an Advanced Chip-in-Board Assembly

For an experimental ETDM fiber transmission systems working at 20 Gbit/s and an OTDN 40 Gbit/s system the electronic transmitter. receiver. and amplifier modules were developed. To guarantee reliable and error free operation unpackaged GaAs- and Si-chips on ceramic thinfilm substrates in combination with a sophisticated interconnection technology had to be used. We call this technology "Reverse Beam Lead"-technic. It uses self-supporting leads at the ceramic substrate which contact the semiconductor chips and it allows low impedance and rather reflection- and discontinuity-free connections even for millimeter-wave applications.