Design and simulation of a Micro Hotplate for MEMS based integrated gas sensing system

Micro Hotplate (MHP) is one of the main components in micro-sensors, especially in gas sensors. The metal oxide gas sensors utilize the properties of surface adsorption to detect changes in resistance as a function of varying concentration of different gases. To detect the resistive changes, the temperature must be in the requisite temperature range over the heater area. Hence, the sensitivity and response time of the sensor are dependent on the operating temperature of the MHP. Making proper design is of critical importance. In this paper, design and simulation of uniform temperature MHP has been investigated which is best suitable for sensing multiple gases by using array of MHP to get the better sensitivity and better selectivity. So, by improving sensor properties this system would be advanced one. If there is mixture of gases present at the same time then there is a need of this type of gas sensing system. The designing and simulations have been done using the COMSOL 4.2a Multiphysics. MHP also has been the subject of great interest owing to their extensive applications in Bio Sensors for detection of environmental mycobacteria, Toxin detection and other micro-systems.