TY - JOUR
T1 - Gate-bias controlled charge trapping as a mechanism for NO2 detection with field-effect transistors
AU - Andringa, A.
AU - Meijboom, J.R.
AU - Smits, E.C.P.
AU - Mathijssen, S.G.J.
AU - Blom, P.W.M.
AU - Leeuw, de, D.M.
PY - 2011
Y1 - 2011
N2 - Detection of nitrogen dioxide, NO2, is required to monitor the air-quality for human health and safety. Commercial sensors are typically chemiresistors, however field-effect transistors are being investigated. Although numerous investigations have been reported, the NO2 sensing mechanism is not clear. Here, the detection mechanism using ZnO field-effect transistors is investigated. The current gradually decreases upon NO2 exposure and application of a positive gate bias. The current decrease originates from the trapping of electrons, yielding a shift of the threshold voltage towards the applied gate bias. The shift is observed for extremely low NO2 concentrations down to 10 ppb and can phenomenologically be described by a stretched-exponential time relaxation. NO2 detection has been demonstrated with n-type, p-type, and ambipolar semiconductors. In all cases, the threshold voltage shifts due to gate bias induced electron trapping. The description of the NO2 detection with field-effect transistors is generic for all semiconductors and can be used to improve future NO2 sensors.
AB - Detection of nitrogen dioxide, NO2, is required to monitor the air-quality for human health and safety. Commercial sensors are typically chemiresistors, however field-effect transistors are being investigated. Although numerous investigations have been reported, the NO2 sensing mechanism is not clear. Here, the detection mechanism using ZnO field-effect transistors is investigated. The current gradually decreases upon NO2 exposure and application of a positive gate bias. The current decrease originates from the trapping of electrons, yielding a shift of the threshold voltage towards the applied gate bias. The shift is observed for extremely low NO2 concentrations down to 10 ppb and can phenomenologically be described by a stretched-exponential time relaxation. NO2 detection has been demonstrated with n-type, p-type, and ambipolar semiconductors. In all cases, the threshold voltage shifts due to gate bias induced electron trapping. The description of the NO2 detection with field-effect transistors is generic for all semiconductors and can be used to improve future NO2 sensors.
U2 - 10.1002/adfm.201001560
DO - 10.1002/adfm.201001560
M3 - Article
SN - 1616-301X
VL - 21
SP - 100
EP - 107
JO - Advanced Functional Materials
JF - Advanced Functional Materials
IS - 1
ER -