Investigation of Sensors Based on ITO Nanofilms in SPR-Devices

Abstract

Devices based on surface plasmon resonance (SPR) are used to determine the refraction index (RI) of liquids and gases. In these cases, as a sensitive element (SE), they use precious materials. It is also known that RI of an investigated substance (analyte) depends on temperature, which brings in some errors into results of measurements. The existing construction solutions for controlling and adjusting the analyte temperature possess a number of deficiencies, namely: high inertness and consumption power. The aim of this work was to study the possibility of using ITO films (In 2 O 3 -SnO) as SE and thin-film heaters in SPR devices to enhance their accuracy. For the first time, excitation of SPR by using the wavelength 650 nm in ITO films has been proved experimentally. It has been also shown that using the heaters based on ITO films reduces the error of measuring the analyte RI by 1.8 times and the consumed power – by 2.3 times as compared with the existing heaters of the resistive type that are used now in SPR devices.