Room Temperature Ammonia Gas Sensing Using Mixed Conductor based TEMPOS Structures

Sensors

Mamta Saroch²  Sunita Srivastava²  Dietmar Fink¹ 

[1] Hahn-Meitner-Institute, Glienicker Str. 100, D-14109 Berlin, Germany; E-mail:;Department of Physics, Panjab University, 160014 Chandigarh, India; E-mails:

关键词: Etched ion tracks;    TEMPOS structures;    ammonia sensors;    impedance measurements;   

DOI  :  10.3390/s8106355

来源: mdpi

【 摘 要 】

The current/voltage characteristics of mixed (ion+electron) conductor-based ‘TEMPOS’ (Tunable Electronic Material with Pores in Oxide on Silicon) structures̵ are reported. TEMPOS are novel electronic MOS-like structures having etched swift heavy ion tracks (i.e., nanopores) in the dielectric layer filled with some conducting material. The three contacts (two on top and one on the bottom), which resemble the classical bipolar or field effect transistor arrangements are, in principle, interchangeable when the overall electrical resistance along the tracks and on the surface are similar. Consequently, three configurations are obtained by interchanging the top contacts with the base contact in electronic circuits. The current/voltage characteristics show a diode like behaviour. Impedance measurements have been made for TEMPOS structures with tracks filled with ion conductors and also mixed conductors to study the ammonia sensing behaviour. The impedance has been found to be a function of frequency and magnitude of the applied signal and concentration of the ammonia solution. This is attributed to the large number of charge carriers (here protons) available for conduction on exposure to ammonia and also to the large surface to volume ratio of the polymer composites embedded in the ion tracks. The measurement of both, the real and imaginary parts of impedance allows one to enhance the detection sensitivity greatly.

【 授权许可】

CC BY   
© 2008 by the authors; licensee Molecular Diversity Preservation International, Basel, Switzerland.