Reflectivity of Porous Silicon

Multiparametric Porous Silicon Sensors

We investigated the possibility of using several sensing parameters from porous silicon in order to improve gas selectivity. By fabricating porous silicon optical microcavities, three independent quantities can be measured, i.e. the electrical conductance, the photoluminescence intensity, and the wavelength of the optical resonance. We monitored the change of these three parameters as a functio...

Porous - silicon microcavities ( * )

The properties and preliminar applications of porous-silicon (p-Si) microcavities are here reported. These structures are based on a planar resonator formed by two narrow-band high-reflectance distributed Bragg reflectors separated by a thin active optical layer, all of which are made of' p-Si layers. The accurate control of the electrochemical dissolution of Si lets us realize p-Si multilayers...

Porous Silicon Biosensors

MEMS Applications of Porous Silicon

Porous silicon fabricated by partial electrochemical dissolution of bulk silicon, shows outstanding material properties. The nanostructure of the remaining Si-skeleton is used for specific optical devices, such as emitters and filters. The high internal surface of the material opens new opportunities for different types of microsensors and -actuators and microsystem concepts. The porous layers ...

Femtosecond Pump-Probe Reflectivity Study of Silicon Carrier Dynamics

We have studied the ultrafast optical response of native-oxide terminated Si~001! with pump-probe reflectivity using 800 nm, 28 fs pulses at an excitation density of (5.560.3)310 cm. Time-dependent reflectivity changes comprise third-order-response coherent-transient variations arising from anisotropic state filling and linear-response variations arising from excited free carriers, state fillin...