PN DIODE OPTICAL MODULATORS FABRICATED IN RIB WAVEGUIDES

摘要

High speed optical modulators (100) can be made of a reverse biased lateral PN diode (105) formed in a silicon rib optical waveguide (112) disposed on a SOI or other silicon based substrate (100). A PN junction is formed at the boundary of the P and N doped regions (120, 130) The depletion region at the PN junction (106) overlaps with the center of a guided optical mode propagating through the waveguide (110). Electrically modulating a reverse biased lateral PN diode (105) causes a phase shift in an optical wave propagating through the waveguide (110). Prior art forward biased PN and PIN diode modulators have been relatively low speed devices.