Silicon-on-insulator guided-wave structures for thermo-optic switching applications

A theoretical study aimed at the optimum design of thermo-optic guided-wave switches realized in silicon-on-oxide technology is reported. The heat transfer processes occurring inside such devices are analyzed by means of a 3-D finite element thermal simulator. In particular, in rib waveguiding structures, we demonstrate that the optimum values of the oxide layer thickness and of the outer rib height are a function of the heating pulse power used to drive the device. The theoretical results carried out are consistent with the experiments reported in literature.