Thick film NTC thermistor for wide range of temperature sensing

摘要

Purpose – Aims to focus on temperature sensors. Design/methodology/approach – Negative temperature co-efficient thermistor powders of ternary Mn, Co, Ni oxide along with RuO2 synthesized at relatively moderates temperature (1,000℃). Thick film thermistor paste compositions were formulated by mixing the semiconducting oxide powder, glass frit and organic vehicle. The physico-chemical analysis, viz. X-ray diffraction, scanning electron microscopy and thermogravimetry and IR spectroscopy were carried out for the synthesized powder and the resultant thick films. The X-ray analysis of the powders showed the cubic spinel structure. The electrical properties like thermistor constant, sensitivity index and activation energy of the thick film NTC thermistor were determined. Findings – The room temperature resistance is observed to range from 490KΩ to 4.13MΩ with thermistor constant ranging from 3,275 to 3,980 K, in the temperature range of 25-300℃. Originality/value – Describes research work on temperature sensors that are used for monitoring and control in many fields such as in home appliances, manufacturing industries, biomedical and automobile industries.