title: Silicon-nitride surface passivation of submicrometer silicon waveguides for low-power optical switches.
abstract: We report on a Si(3)N(4)-based surface-passivation technique for increasing free-carrier lifetimes in submicrometer silicon-on-insulator waveguides by up to 2 orders of magnitude. The carrier lifetime was measured by injecting free carriers into a critically coupled ring resonator through photoexcitation by short pump pulses and subsequently tracking the spectral detuning of the resonator during the carrier-recombination phase. Carrier lifetimes of up to 70 ns were obtained in waveguides passivated with a 45-nm-thick Si(3)N(4) coating. Such surface passivation is essential for low-power operation of optical switches based on carrier injection.
authors.affiliation: IBM Research, T. J. Watson Research Center, Yorktown Heights, New York 10598, USA. jvancam@us.ibm.com
authors.forename: Joris
authors.initials: J
authors.lastname: Van Campenhout
authors.forename: William M J
authors.initials: WM
authors.lastname: Green
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Liu
authors.forename: Solomon
authors.initials: S
authors.lastname: Assefa
authors.forename: Richard M
authors.initials: RM
authors.lastname: Osgood
authors.forename: Yurii A
authors.initials: YA
authors.lastname: Vlasov