Innovative design for optical porous silicon gas sensor

A simple system for the detection of analytes in the atmosphere employing a freestanding nanostructured porous silicon optical microcavity was designed and built. The system is based on the measurement of optical transmittance changes as a function of the incidence angle of a monochromatic laser bea...

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Detalles Bibliográficos
Autores: Acquaroli, Leandro Nicolás, Urteaga, Raul, Koropecki, Roberto Roman
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2010
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/13446
Acceso en línea:http://hdl.handle.net/11336/13446
Access Level:acceso abierto
Palabra clave:Nanostructured Silicon
Photonic Crystal
Chemical Sensor
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Descripción
Sumario:A simple system for the detection of analytes in the atmosphere employing a freestanding nanostructured porous silicon optical microcavity was designed and built. The system is based on the measurement of optical transmittance changes as a function of the incidence angle of a monochromatic laser beam. Using a matrix formalism and effective medium theories we calculate the optimal conditions for the system so as to obtain the best sensitivity of the sensor. We tested the system over a detection area of the porous silicon microcavity of 100 micro m2 with isopropyl alcohol vapor diluted in a N2 stream. With the system proposed we were able to detect changes in the concentration of isopropyl alcohol as small as 1 ppm, which is equivalent to a change in the effective refractive index of about 3×10-6. The response time is very fast, lower than 0.5 s.