Integrated temperature sensor and close-loop control circuit for silicon microring modulator

Microring (MR) devices require thermal stabilization to match their intended operating wavelengths. In this work, we present a scheme for thermal stabilization of MR modulators utilizing integrated temperature sensor and closed-loop control unit based on CMOS integrated circuit. Temperature of the MR modulator is directly monitored by a diode based monolithic temperature sensor. The measured temperature is used in a feedback loop to adjust the thermal tuner of the MR. Thermal steady state and transient simulations are performed showing that temperature tuning range from 30 to 100℃ can be achieved. Considering the relatively slow heat transfer process, unity-gain bandwidth of the control circuit is optimized to ensure loop stability. This design can effectively compensate ambient thermal noise and adjust the deviation of the operating wavelength caused by the process error