Random porous silicon multilayers: application to distributed Bragg reflectors and interferential Fabry - Pérot filters

Abstract

Random porous silicon dielectric multilayers are proposed as interesting materials for applications as optical components. Distributed Bragg reflectors and interferential Fabry-P érot filters are demonstrated. The randomness is obtained as a variation in the layer thicknesses. The advantage in the use of random instead of periodic multilayers lies in the obtention of a wider stop-band in Bragg reflectors with the same difference in the refractive indexes of the layers and in a higher finesse in Fabry-P érot filters.

Nanocrystalline Porous Silicon

“…The nano sized voids in the bulk silicon result in a sponge-like structure of pores and channels surrounded by a skeleton of crystalline Si nano wires. Porous silicon (PS) is gaining scientific and technological attention as a potential platform mainly for its multifarious applications in sensing and photonic devices (Canham, 1997a;Pavesi & Dubos;Dimitrov,1995;Tsamis et al, 2002;Archer & Fauchet, 2003;Barillaro et al,2003). The extremely large surface to volume ratio (500m 2 /cm 3 ) of PS, the ease of its formation, control of the surface morphology through variation of the formation parameters and its compatibility to silicon IC technology leading to an amenability to the development of smart systems-on-chip sensors have made it a very attractive material.…”

XPS study of palladium sensitized nano porous silicon thin film

“…It has a wide range of applications in photonics and optoelectronics, quantum electronics, silicon-on insulator technology and recently in sensors (Dimitrov 1995;Pavesi and Dubos 1997;Tsamis et al 2002). In spite of all advantages the major barrier against the commercial applications of PS is the temporal degradation of its surface property in oxygen or moisture containing environment and the difficulty in obtaining reliable ohmic contacts (Barillaro et al 2003).…”

Silicon as an emissive optical medium

“…To allow PS to emit in a narrow-band, PS microcavities, wherein a PS layer is sandwiched between two distributed PS Bragg reflectors has been utilized [39][40][41]. Using this technique, luminescence with a full width at half maximum of 14-20 nm in the wavelength range of 700-810 nm was achieved [41].…”