A Novel Low Power Hexagonal Gas Sensor Cell for Multi-Channel Gas Detection

This paper reports a low power, high sensitive metal oxide gas sensor cell with novel hexagonal structure for multi-channel gas detection. Six sensors are integrated with a hexagonal micro-hotplate to make up the sensor cell. The hexagonal micro-hotplate was designed and fabricated using MEMS technology, and the sensing material SnO
₂
was directly deposited by sputtering, which shows excellent semiconductor process compatibility. The active region of the sensor cell is 600×520 μm
²
. The sensor cell achieves 6-channel detection of ethanol at one time in a large voltage supply range of 2.0 V to 3.0 V. With an input voltage of 3.0 V (5.85 mW×6), the highest response (R
_air
/R
_gas
) of the sensor cell is 16.93 (94.1% sensitive resistance change). The average power consumption of the sensor cell is just 3.03 mW when the sensor cell starts responding to ethanol.