Innovative design for optical porous silicon gas sensor

SENSORS AND ACTUATORS B-CHEMICAL

卷:149

Article

Acquaroli, L. N.¹  Urteaga, R.^1,2  Koropecki, R. R.^1,2 

[1] Consejo Nacl Invest Cient & Tecn, UNL, Inst Desarrollo Tecnol Ind Quim, RA-3000 Santa Fe, Argentina

[2] UNL, Fac Ingn Quim, RA-3000 Santa Fe, Argentina

关键词: Porous silicon;    Gas sensor;    Optical properties;    Microcavities;   

DOI  :  10.1016/j.snb.2010.05.065

来源: Elsevier

【 摘 要 】

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 mu m(2) with isopropyl alcohol vapor diluted in a N(2) 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 x 10(-6). The response time is very fast, lower than 0.5 s. (C) 2010 Elsevier B.V. All rights reserved.

【 授权许可】

Free