Electro-optic (EO) polymers are the promising material of choice for the waveguide modulation application due to their high EO coefficient, optical transparency, low dielectric loss, and compatibility with many materials and substrates. This widespread compatibility enables the construction of the unique hybrid polymer device to the silicon waveguide. One of the successful demonstrations in recent progress is the hybrid silicon modulator to the EO polymer. The hybrid silicon and polymer modulators have already demonstrated a very low half-wave voltage and multi-GHz bandwidth response. While, the fabrication is quite elaborate, involving the high-resolution lithography, controlled etching, and ion implantation process. In order to simplify the hybrid silicon and EO polymer modulator, we apply the conventional photolithography technique. The waveguide consists of silicon core with a thickness of 30 nm and a width of 2 m, and the cladding is the polymer. In such a thin silicon core, the side-wall scattering can be significantly reduced, thus the measured propagation loss of the waveguide is 1.5 dB/cm. The optical mode calculation reveals that 55% of the optical field extends into the polymer cladding. The hybrid phase modulator waveguide performed the half-wave voltage of the modulator to be 4.6 V at 1550 nm and excellent temperature stability at 85C for longer than 500 hours. We also investigate a mode converter which can couple the light from the hybrid polymer waveguide to the silicon strip waveguide. The coupling loss between two devices is measured to be 0.5 dB.

Date Published: 3 November 2016
PDF: 1 pages
Proc. SPIE 9939, Light Manipulating Organic Materials and Devices III, 99390C (3 November 2016); doi: 10.1117/12.2237450

Published in SPIE Proceedings Vol. 9939:
Light Manipulating Organic Materials and Devices III
Joy E. Haley; Jon A. Schuller; Manfred Eich; Jean-Michel Nunzi, Editor(s)