Thermal vacuum sensor with compensation of heat transfer

The results of investigation on thin-film vacuum sensor have been presented. The sensor was composed of a heating resistor and a thermopile, which were made by thin-film technology on a glass foil substrate. To improve the sensitivity of the sensor and extend its measurement range, a special design was chosen, which enabled us to reduce the heat transfer by radiation and thermal conduction of the substrate. Reduction of heat transfer from the substrate was accomplished by incorporation of additional plate, which also contained a heating resistor and a thermopile. The additional heating resulted in reduction of heat transferred from the sensor plate. The measurements of sensor characteristics versus pressure have been done. An increase in sensitivity and extension of measurement range from the side of lower pressures have been achieved. The measurement range of the sensor was 2 x 10(-3) to 10(3) Pa. (C) 2001 Elsevier Science B.V. All rights reserved.