HIGH-TEMPERATURE SEMICONDUCTOR SENSOR FOR THE DETECTION OF FLUORINE

A chemical semiconductor sensor based on a silicon carbide substrate w as investigated for the high temperature measurements of fluorine up t o 350 degrees C. The use of the structure SiC/SiO2/LaF3/Pt at room tem perature leads to results comparable to the silicon based sensor. The influence of the temperature on the sensor response time was smaller t han expected but the increased desorption rate and a high signal to no ise ratio improved the detection limit. An impulse method using the in itial slope of the response curve was shown to be advantageous. (C) 19 98 Elsevier Science S.A. All rights reserved.