Patent ID: 8363986
Filing Date: 2013-01-29
Classification: G02B,G02F

Abstract:
1. A silicon-based optical modulating device comprising: a silicon body layer doped to exhibit a first conductivity type; a silicon gate layer doped to exhibit a second conductivity type, the silicon gate layer disposed at least in part to overlap the silicon body layer to define a contiguous area between said silicon body and gate layers; a relatively thin dielectric layer disposed in the contiguous area between said silicon body and gate layers, the combination of said silicon body and gate layers with the interposed relatively thin dielectric layer defining the active region of the optical modulating device; a first electrical contact coupled to an outer, contact portion of the silicon gate layer; and a second electrical contact coupled to an outer, contact portion of the silicon body layer, wherein upon application of an electrical signal to the first and second electrical contacts, free carriers accumulate, deplete or invert within the contiguous areas of silicon body and gate layers on both sides of the relatively thin dielectric layer, such that the optical electric field of said optical signal substantially overlaps with the free carrier concentration modulation area in the active region of said optical modulating device, where the silicon body and gate layers are doped to exhibit a lowest dopant concentration in the active region and a highest dopant concentration in the respective outer portions, with at least one of the silicon body and gate layers further exhibiting an intermediate dopant concentration in an intermediate region between the respective active region and the contact portions.