A Warped-Cantilever MEMS MOS Gas Sensor Array

In this paper, a warped-cantilever metal oxide semiconductor (MOS) gas sensor array is prepared using MEMS technology and rolling of stressed heterofilms technology. The warped cantilever, which is made of SiO
2
/SiNx heterofilms, allows for bulk loading of sensitive materials at the wafer level. Based on the structure of the single cantilever, 12 sensors can be fabricated inside a die of 1 mm
²
, improving the integration by magnitude. Moreover, using the silicon surface sacrificial layer process, the entire process of device manufacturing is CMOS compatible. The measurement results indicate that the static power consumption is only 5.81 mW. With this applied power, the sensor can heat up to a temperature of 400°C within just
$300\ \mu\mathrm{s}$
. Choosing SnO
2
as the sensitive material, the sensor shows a relatively high sensing response of 6.5 in 100 ppm ethanol/air gas.