||SOI-based optical interconnects for on-chip applications have been attentions in recent years. In order to achieve the high flexibility and compact integrations in the on-chip optical-interconnect systems, optical waveguide splitters are important component in the on-chip systems. We demonstrate the three-dimensional optical path with 13 output ports using SOI-based vertically-splitting optical waveguides. The vertically-splitting optical waveguides include 45-dgree micro-splitters and 45-degree reflecting trapezoidal waveguides, and integrate vertical-cavity surface-emitting laser (VCSEL), photodiode (PD), integrated circuit (IC) in one silicon substrate in the future. It is first time to demonstrate 1multiple optical routing structure in one channel.|
In the proposed optical waveguides, optical path penetrates through the substrate and coupled into the silicon waveguide, then vertically reflected to the receivers by splitting structure in the silicon waveguide to realize vertically-splitting three-dimensional optical waveguides. The SOI-based vertically-splitting waveguide is fabricated on an orientation–defined (100) SOI substrate using a two-step anisotropic wet-etching process.
According to the optical simulated and experiment results, in the 13 output ports using SOI-based vertically-splitting optical waveguides, the optical coupling efficiency of output ports achieve -10.8 dB, -11.74 dB and -8.45 dB. This high optical–quality 13 output ports using SOI-based vertically-splitting optical waveguides will be realized in the On-chip interconnect module.
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