We demonstrate the fabrication of an out-of-the-plane Fabry-Perot interferometer (FPI) `on-a- chip' using the single crystal reactive etching and metallization (SCREAM) process. A modified version of this process is also developed to generate a fully suspended Fabry-Perot interferometer (FPI) `on-a-frame.' The optical device is mounted on a released frame, which includes suspended contact pads and oxide isolating segments. During the process, the total structure (with 8.6 mm2 surface area) is fixed to the substrate through serpentine springs. Then, using a pair of fine tweezers, these springs are clipped and the thin membrane- like structure is lifted off the substrate and placed exactly between self-aligned input and output single-mode optical fibers. The suspended FPI `on-a-frame' is made from freely released beams of dimensions comparable to fiber diameter with a vertical depth of 107.5 micrometers . The mirrors of the FPI, which consist of a series of (lambda) /4 SiO2 and Si film stacks separated by an initial gap distance of 10 micrometers , attract each other when a bias is applied across these capacitor-type plates and tune broad-band IR light into a specific wavelength.
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