Pulse Biasing Scheme for the Fast Recovery of FET-Type Gas Sensors for Reducing Gases

The promotive effect of a pre-bias condition on the recovery speed of a field-effect transistor-type gas sensor, which has a horizontal control gate (CG) and floating gate (FG), is investigated in this letter. To verify the pre-bias effect in the recovery phase after the detection of H 2 S gas, a ty...

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Bibliographic Details
Published inIEEE electron device letters Vol. 38; no. 7; pp. 971 - 974
Main Authors Wu, Meile, Shin, Jongmin, Hong, Yoonki, Jin, Xiaoshi, Lee, Jong-Ho
Format Journal Article
LanguageEnglish
Published IEEE 01.07.2017
Subjects
FET platform
Field effect transistors
Gas detectors
gas sensor
Gases
Logic gates
Pre-bias effect
Pulse measurements
recovery speed
reducing gas
Temperature measurement
work-function
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Summary:The promotive effect of a pre-bias condition on the recovery speed of a field-effect transistor-type gas sensor, which has a horizontal control gate (CG) and floating gate (FG), is investigated in this letter. To verify the pre-bias effect in the recovery phase after the detection of H 2 S gas, a type of reducing gas, a 200-nm-thick layer of SnOx is deposited on top of the interdigitated CG and FG as a sensing material. A pulse measurement method is proposed to improve the recovery speed of the sensor for H 2 S gas sensing by applying a negative pre-bias condition to the CG before the read operation of the sensor. This method greatly accelerates the recovery and reduces the recovery time by 74% with a pre-bias of -3 V at 180°C. The mechanism is explained in terms of energy band theory. The pre-biasing method used with our gas sensor is beneficial for the continuous monitoring and for the rapid detection of various gases.
ISSN:0741-3106
1558-0563
DOI:10.1109/LED.2017.2707592