Platinum Resistance Microsensor for Cryogenic Temperature Measurement

Abstract

Platinum resistance temperature sensor is applied to the temperature range higher than 200K currently. Through studying the principle of platinum temperature sensor, the platinum resistance temperature microsensor can be used in the temperature region between 10K and 200K was studied. It employs symmetrical turn back structure, which effectively avoids the inductance caused by alternating current (AC). Fabrication process based on MEMS technology was illustrated. The platinum film was obtained by direct current (DC) magnetron sputtering deposition and the platinum resistance temperature microsensor was fabricated with 200nm thickness layer film. The relationship between resistance and temperature of platinum microsensor was tested by Quantum QD PPMS instrument. When T>30K and T<30K, TCR of platinum microsensor could achieve 16490ppm/K and 6430ppm/K respectively. Thus, the microsensor can be used as temperature sensing element between 10K and 200K in the cryogenics.