0.88-THz Optical Clock Distribution on Adhesively Bonded Silicon Nanomembrane

Silicon photonics is a promising solution for on-chip optical clock distribution. We developed an adhesive bonding process to integrate silicon nanomembranes onto silicon chips. The single-mode strip waveguide fabricated on this adhesively bonded silicon membrane has a propagation loss of 4.3 dB/cm. A grating-coupled 1-to-32 H-tree optical distribution is experimentally demonstrated. Each branch includes 1.1-cm long strip waveguides, five Y-splitters, and three 90° bends. This optical distribution has a insertion loss of 13.9 dB, uniformity of 0.72 dB, and 3-dB bandwidth of 880 GHz determined by optical autocorrelation.