THERMOMETRIC MODEL OF DIODE TEMPERATURE SENSOR

Abstract

Pavlov L.M., Yahanov P.O. THERMOMETRIC MODEL OF DIODE TEMPERATURE SENSOR   Background.  Microelectronic technologies make it possible to create structures with high sensitivity to external influences. In semiconductor microelectronics, these are structures of the type of potential barrier at the p-n junction. Silicon diode sensors have high temperature sensitivity in a wide temperature range. Both physical and formal mathematical models of the thermometric characteristic of the diode sensor have been developed. The temperature measurement error of some of these methods was not acceptable for the control of many processes. It is relevant to conduct studies of the temperature properties of the p-n transition in a non-equilibrium state to formalize the new thermometric characteristic of the diode sensor. Objective. The purpose of the work is a model of thermometric characteristics of silicon diode sensors based on the results of measurements of volt-ampere characteristics in the temperature range. Methods. Analysis of methods of calibration of thermometric characteristic of diode sensors by volt-ampere characteristics was carried out, factors affecting temperature measurement accuracy were revealed, regression analysis method for formation of polynomial model of thermometric characteristic was substantiated. Results. As a result of studies of the volt-ampere characteristics of silicon diodes in the temperature range (248... 393) K, it was found that the error in measuring temperature by diode sensors is associated with the dependence of the non-ideality factor of the p-n transition on temperature. The accuracy of the thermometric characteristic is estimated, where this functional dependence is represented as an approximation polynomial. Conclusions.  An alternative model of thermometric characterization of diode temperature sensors by the second degree regression equation is presented. The arguments of the function are the current and voltage of the diode in the direct displacement mode. Current stability in the p-n junction circuit is not assumed. The temperature determination accuracy in the temperature range (248... 393) K is within ± (0.2... 0,256) K. Keywords: diode temperature sensors; volt-ampere characteristic; non-ideality factor; regression; thermometric characteristic model.