MEMS Chemometric/Calorimetric Sensor for CH4 and CO2 Detection

The MEMS sensors for CO2 (carbon dioxide) and CH4 (methane) detection, from Sitex 45 (Romania) have an operating principle based on the change in conductivity due to chemisorbtion a/o calorimetric effects of gas molecules to be detected at the sensitive layer surface.

The integrated heating element consists of a polysilicon layer underneath the active area. A temperature sensitive resistor will enable precisely temperature control. The sensor is integrated as MEMS in CMOS technology compatible by adding special micromachining processes.

Different polymeric films sensitivity gases to be analysed, exhibit changes of conductance in presence of small gases concentration at ppm level.

The sensitivity and stability of MEMS sensors are corresponding for applications during the measurement at room temperature of polluted air .or air noxes detection.

In some cases a temperature of up to 300° could be applied for cleaning the sensitive polymer in order to reuse the sensor. 

Advantages: Increased reproductibility, High MEMS sensors miniaturization degree, Microsystem integration in package (sensors, electrodes), Low power consumtion, portable devices approaches, High working versatility as integrated or individual packaged sensors, Very low weight ~ 3 g.

Applications: Environmental protection and monitoring, Medical and health care applications, Industrial facilities and utilities networks and production plants, Chemical and biochemical technological processing, and Safety and defence industry and applications.