Patent ID: 8320720
Filing Date: 2012-11-27
Classification: G02F,H04B

Abstract:
1. A silicon-based optical modulating device for converting an N-bit electrical data signal into a modulated optical output signal, the modulating device formed within a silicon-on-insulator (SOI) structure including a silicon substrate, a buried oxide later disposed over the silicon substrate and a sub-micron thick silicon surface layer (SOI layer) disposed over the buried oxide layer and comprising an input waveguiding section formed within the SOI layer for receiving a continuous wave (CW) optical input signal; an input optical splitter formed within the SOI layer and coupled to the output of the input waveguiding section for dividing the CW optical input signal into a pair of CW optical signals; a pair of optical waveguides formed within the SOI la er and coupled to the outputs of the input optical splitter, the pair of optical waveguides forming a pair of modulator arms for supporting the propagation of the pair of CW optical signals, at least one modulator arm partitioned into a plurality of M modulator segments, with each modulator segment comprising a silicon layer disposed in an overlapped arrangement with an oppositely-doped portion of the SOI layer and including a thin dielectric layer disposed therebetween to form a silicon-insulator-silicon capacitance (SISCAP) modulator segment based upon movement of free carriers between the doped silicon layer and the oppositely-doped portion of the SOI layer; a digital encoder for translating the N-bit electrical data signal into a plurality of M drive signals for the plurality of M modulator segments with M ≧2 an output optical combiner formed within the SOI layer for combining the pair of modulated optical signals into a modulated optical output signal; and an output waveguiding section formed within the SOI layer and coupled to the output of the output optical combiner for supporting the propagation of the modulated optical output signal.