Multilayer 3-D Photonics in Silicon

California Univ., Los Angeles
Optics Express (Impact Factor: 3.49). 11/2007; 15(20):12686-91. DOI: 10.1364/OE.15.012686
Source: PubMed


Three-dimensionally (3-D) integrated photonic structures in multiple layers of silicon are reported. Implantation of oxygen ions into a silicon-on-insulator substrate with a patterned thermal oxide mask, followed by a high temperature anneal, creates photonic structures on 3-D integrated layers of silicon. This process is combined with epitaxial growth to achieve devices on three vertically integrated layers of silicon. As a demonstration vehicle, we report a multistage optical filter that comprises of coupled microdisks on two subsurface silicon layers with bus waveguides on the surface (3rd) layer. The optical filter shows extinction ratios in excess of 14 dB, with excess insertion loss of less than 1 dB.

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    • "The field of silicon photonics [1] [2] holds promise for 3-D integration [3] [4] with compact, high-contrast dielectric optical waveguides at different levels of photonic chips. This might concern small vertical distances, such that evanescent coupling between overlapping components becomes possible, but just as well optically well separated waveguides at larger vertical separations. "
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