Fully Integrated Mach-Zhender MEMS Interferometer With Two Complementary Outputs

In this paper, a novel Mach-Zhender interferometer for spectroscopy applications is presented. The interferometer is fully integrated on an silicon on insulator wafer using deep reactive ion etching technology, the moving mirror is coupled to a comb drive microelectromechanical systems (MEMS) actuator. Optical propagation inside the MEMS structure is modeled and the diffraction effect is studied. Practical results show the complementary nature of the two outputs and a resolution of 25 nm at 1.55 μm is reported when using the interferometer as an Fourier transform infrared spectrometer. The complementary nature of the interferometer can be further used for source noise reduction.