OPTICAL DEVICE INCLUDING GATE INSULATOR WITH EDGE EFFECT

摘要

An optical device including a gate insulator with an edge effect is provided to improve a change of a refractive index or an optical attenuation effect without deterioration of a dynamic characteristic by increasing an optical confinement factor of a charged layer near a gate insulating film. An optical device including a gate insulator with an edge effect includes a semiconductor substrate(102), an insulator(104), a first semiconductor layer, a gate insulating film(150), and a second semiconductor layer. The insulator is arranged on the semiconductor substrate. The first semiconductor layer is doped with a first conductive impurity arranged on the insulator and has a recessed groove(152) on a top part thereof. The gate insulating film covers the groove and a part of the first semiconductor layer. The second semiconductor layer covers the gate insulating film and is doped with a second conductive impurity opposite to the first conductive impurity.