Design of monolithic band-pass filter using high performance passive and active component technology for WLAN applications

The trend for low-cost, small dimension, thin profile, multi-function and multi-mode handheld wireless devices are required by the future user. In this paper, we present the design of an Electrostatic Discharge (ESD)-protection free band-pass filter (BPF) in an improved high resistivity silicon copper technology for the monolithic integration of active and passive devices. Inter-digital metal capacitors instead of typical Metal-Isolator-Metal (MIM) capacitors are used for better quality factor and higher breakdown voltage of up to 800 V. Electromagnetic (EM) simulation was extensively used in this design for inductor and filter optimization. The fabricated device by the first run has an insertion loss of less than 2 dB and an out of band attenuation of more than 25 dB for the WLAN 2.4 GHz frequency band and features a size of 1.0×1.3 mm².