Desarrollo de un sensor de especies gaseosas basado en microcavidades ópticas de silicio poroso nanoestructurado

L.N. ACQUAROLI; RAÚL URTEAGA; R.R. KOROPECKI

Congreso; 95a Reunión Nacional de la Asociación Física Argentina; 2009

Asociación Física Argentina

A simple system for the detection of external analytes (EA) to the atmosphere employing nanostructuredporous silicon optical microcavities was design and built. The system is based on themeasurement of the transmittance changes as a function of the incidence angle of a monochromaticlaser beam. Using a matrix formalism and effective medium theories we calculate the optimalconditions for the system so as to obtain the best sensitivity of the sensor. In this work we test thesystem with isopropyl alcohol vapor diluted in a N2 stream. With the system proposed we were ableto detect changes in the concentration of the EA as small as 1 ppm, which is equivalent to a changein the refractive index of 10−6. Below this value, variations in temperature become significant andmust be taken into account to obtain reliable measurements.