A deep submicrometer CMOS process compatible high-Q air-gap solenoid inductor with laterally laid structure

A high-quality (Q) on-chip solenoid inductor has been fabricated by 0.18 mm CMOS technology with air-gap structure. The solenoid structure with laterally laid out structure saves the chip area significantly and the air-gap suppresses the parasitic capacitances to obtain high-Q value. Additionally, with software ANSYS simulation, the solenoid inductor also possesses a higher strength for impact (80 000 times) in comparison to a spiral inductor. The measured peak-Q and peak-Q frequency with an air-gap are 8.8 and 1.7 GHz, respectively, which present almost 9% improvements in the magnitude and 54% in the peak-Q frequency in comparison to the conventional solenoid inductor at 8.1 and 1.1 GHz.