Complementary metal-oxide-semiconductor compatible athermal silicon nitride/titanium dioxide hybrid micro-ring resonators

Micro-ring resonators have been widely utilized in silicon photonics. However they often exhibit a high sensitivity to ambient temperature fluctuations. In this letter, we have demonstrated a complementary metal-oxide-semiconductor compatible athermal micro-ring resonator made from titanium dioxide (TiO2) and silicon nitride (SiNx). We have exploited the negative thermo-optic coefficient of TiO2 to counterbalance the positive coefficient of SiNx. By a precise control over the TiO2 layer thickness, an athermal condition remarkably consistent with the simulation can be achieved. Therefore, a SiNx-TiO2 hybrid micro-ring resonator with a temperature dependent wavelength shift of 0.073 pm/degrees C has been realized. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4790440]