Porous Silicon/Silicon Hybrid Substrate Applied to the Monolithic Integration of Common-Mode and Bandpass RF Filters

In order to develop high performances and miniaturized devices for RF communications, monolithic integration becomes an important challenge for microelectronics industries. Bandpass filters and common-mode filter have been integrated on 6-in porous silicon (PS)/silicon hybrid substrates with PS regions under passive devices. An improvement of the rejection level on common mode was demonstrated on PS regards to low-resistivity silicon. Furthermore, the bandwidth differential was increased regards to bulk silicon and, thus, allows the development of devices for high-speed communications systems.