Ultrasmall thermally tunable microring resonator with a submicrometer heater on Si nanowires

• An ultracompact widely tunable thermooptical (TO) microring resonator (MRR) filter based on Si nanowires is presented. The Si nanowire waveguide has a SiO2 insulator, Si core, a SiO2 up-cladding, and a thin metal film at the top. The metal circuit along the microring is used as a submicrometer heater which has the same width as the Si nanowire waveguide. The up-cladding is optimized to reduce the light absorption of the metal as well as to have a good heat-conduction from the heater to the Si core. Two pads used as the contact points for the probes connecting to the electrical power are perpendicularly connected to the microring by using optimized T-junctions (with a low excess loss of about 0.06 dB per T-junction). With such a design, the present thermally tunable microring resonator (MRR) can be fabricated by using a standard fabrication process with a single lithography process, which is much simpler than the fabrication with double lithography processes used for the conventional TO components. Finally, the simulation results show that the designed MRR has a wide tuning range of about 20 nm with a low heating power of 5 mW.

Keyword

filter

microring

nanowire

resonator

Si

thermal

tunable

silicon-on-insulator

wire wave-guides

ring resonators

fabrication

technology

wavelength

filters

switch

power

Publication and Content Type

ref (subject category)

art (subject category)