Silicon-nitride surface passivation of submicrometer silicon waveguides for low-power optical switches.
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.
Van Campenhout
Joris
J
IBM Research, T. J. Watson Research Center, Yorktown Heights, New York 10598, USA. jvancam@us.ibm.com
Green
William M J
WM
Liu
Xiaoping
X
Assefa
Solomon
S
Osgood
Richard M
RM
Vlasov
Yurii A
YA