A defect-enhanced silicon photodiode and heater are integrated with and used to thermally stabilize a microring modulator. These optoelectronic components are interfaced with external control circuitry to create a closed-looped feedback system for thermally stabilizing the microring modulator. The thermal stabilization system enables the microring modulator to provide error-free 5-Gb/s modulation while being subjected to thermal fluctuations that would normally render it inoperable.