Modeling and simulation of NTC thick film thermistor geometries

Abstract

Purpose

The paper aims to focus on thick film planar thermistors.

Design/methodology/approach

Thick film planar thermistors such as rectangular, sandwich, multilayer, segmented and interdigitated were printed of law temperature NTC paste called NTC 3K3 95/2 (Ei Iritel). Their resistivity was measured at room temperature as a function of volume resistivity variations due to electrode effect (diffusion of PdAg into NTC layer) and variation of geometrical parameters such as length l, width w, thickness d, number of segments n. The experimental data obtained were used in forming a model by the simple fitting procedure for counting diffusion effect on volume resistivity and resistivity dependence on geometrical parameters.

Findings

Thermal behavior of NTC thick films was measured in the range of −30‐120°C. Exponential factor B was fitted for measured values and included in the proposed thick film thermistors model. The agreement of measured and calculated data enables simulation of new thermistor geometries.

Originality/value

The paper focuses on the experiment which was the first step in forming a total physical/mathematical model proposed for thick film thermistor resistivity.

Citation

Aleksić, O.S., Radojčić, B.M. and Ramović, R.M. (2007), "Modeling and simulation of NTC thick film thermistor geometries", Microelectronics International, Vol. 24 No. 1, pp. 27-34. https://doi.org/10.1108/13565360710725919