Coupled varactor based on PN junction and accumulation MOS for RF applications

In this work varactors based on pn-junction have been connected in parallel with accumulation mode MOS ones, in order to increase the final capacitance without losing the particular characteristics. So, three double varactors have been designed, fabricated and on-wafer measured. Results demonstrate that the combination of these varactors improve the global performance in relation to quality factor and tuning range.