Athermal Wavelength Characteristics of Si Slot Ring Resonator Embedded with Benzocyclobutene for Optoelectronic Integrated Circuits

Abstract

An athermal Si-slot-waveguide ring resonator embedded with benzocyclobutene (BCB), a low-k material used in electronics, was proposed. By controlling the width of the BCB-filled gap to 90 nm, the temperature coefficient of equivalent index of a Si slot waveguide could be reduced to 3.70×10-6, which is two orders of magnitude smaller than that of a conventional Si waveguide. The dependences of peak wavelength shift on temperature in the fabricated devices of a conventional Si wire waveguide with SiO2 cladding, Si wire waveguide with BCB cladding, and Si slot waveguide with BCB cladding were 26, 17, and -0.6 pm/K, respectively.