This paper presents the development of sensor in ultrasensitive detection of formaldehyde gas. The chemical compound, tin dioxide (SnO2) thin film is deposited onto glass insulator. Next, the resistance and voltage of the sensing layer on the interdigitated electrodes (IDE) sensor's substrate is measured. The resistivity of sensor is changed by heat the sensing layer to 150°C, 175°C and 200°C. When formaldehyde gas is supplied inside the test chamber, absorption process occurred at the surface of the heated SnO2 sensing layer. The experimental results show the sensor is capable of high sensitivity sensing of formaldehyde gas at 200°C, repeatability, and capability detection as low as 11 ppm which produced 0.8 V on electronic reader. Characterization of surface morphological, temperature effect and electrical properties are demonstrated by various measurements.
