A tunable ring resonator (RR) formed from Si/SiO2 waveguides with an electro-optic polymer cladding is proposed with emphasis on the trade-off between the tuning voltage and ring radius. The ring resonator circuit combines the advantages of Si/SiO2 and polymer technologies. The advantages of this hybrid ring design over previously proposed tunable silicon rings include an increased switching speed, from 5 GHz to 20 to 100 GHz, single-polarity instead of dual-polarity voltage tuning and a voltage-independent quality factor. The hybrid design also displays a greater free spectral range (1.85 nm instead of 0.1 nm) and a wider tuning range (0.925 nm instead of 0.05 nm) and is further compatible with silicon devices. Moreover, the device has a high quality factor of 3.4×104.