A SCS CMOS micromirror for optical coherence tomographic imaging

Reports a single-crystalline silicon (SCS) micromirror used for laser beam scanning in an endoscopic optical coherence tomography (OCT) system. The micromirror is fabricated by using a deep reactive-ion-etch (DRIE) post-CMOS micromachining process. Thin bimorph actuation structures and movable bulk silicon structures are simultaneously achieved. The micromirror is 1 mm by 1 mm in size, coated with aluminum, and thermally actuated by an integrated polysilicon heater. The radius of curvature of the mirror surface is 50 cm. The mirror rotates 17/spl deg/ when a 15 mA current is applied. Cross-sectional images of 500 /spl times/ 1000 pixels covering an area of 2.9 mm by 2.8 mm are acquired at 5 frames/s by using an OCT system based on this micromirror.

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