Fabrication of coplanar microheater platform for LPG sensing applications

The design and fabrication of nichrome based coplanar microheater for LPG sensing applications is presented in this work. Nichrome based coplanar microheater is fabricated using photolithography process. The surface morphology of DC sputtered nichrome is characterized using scanning electron microscope. Electrothermal behaviour of the fabricated microheater is characterized by varying the applied current while the thermal distribution pattern over the active heating area is recorded using thermal imaging camera. The silicon thickness under microheater active area is varied by silicon etching with different time duration in TMAH solution. Silicon thickness effect on maximum temperature of microheater is also investigated experimentally. The tin oxide (SnO2) thin film as LPG sensor is deposited on fabricated coplanar heating platform and it is tested with different amount of LPG concentration.