Micromachined Fourier transform spectrometer on silicon optical bench platform

We present a miniaturized Fourier transform spectrometer implemented on a silicon optical bench platform. The optical and opto-mechanical components of a Michelson interferometer, such as a beam splitter, micromirrors, MEMS actuators, and fiber U-grooves, are simultaneously fabricated by micromachining of the device layer of a silicon-on-insulator wafer. Our bulk micromachining process combines the flexible definition capability of deep reactive ion etching with the good surface quality provided by anisotropic KOH wet-etching. A spectral resolution of 45 nm near 1550 nm wavelength is demonstrated.