Principal effects of ternary oxide dielectric layers on SPR sensors for gas sensing with ellipsometric readout

• Applicant: Dr. Andreas Hertwig
• Subject Area: Coating and Surface Technology
• Term: from 2013 to 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 234234843

The joint project between BAM, Federal Institute for Materials Research and Testing in Berlin and UJEP, the Jan Evangelista Purkyne University in Usti nad Labem aims to investigate new SPR-based gas sensors containing gold layers with thin dielectric overcoatings. Gold layers as SPR devices will be coated with several different additional oxide layers, such as SnO2, ZnO, TiO2, doped with different other metal ions. The main matrix systems investigated will be SnO2 and ZnO. The underlying gold SPR sensor layers will be produced in the coatings lab at BAM and then modified with sputtered oxide layers in the coatings lab at UJEP. These layer systems will be analysed by means of different spectroscopic ellipsometry to evaluate their dielectric function depending on the doping material and its concentration. Subsequently, gas sensing studies will be carried out with these systems evaluating the changes in sensitivity and long-term stability regarding different gasses and gas mixtures. In this case, the gas carbon monoxide is of special interest. The aim of these studies is to find a correlation between the dopant type and concentration of these layers and their properties as gas-sensing devices. The project part located at BAM and proposed for funding hereby will comprise ellipsometric analysis on the manufactured multilayer systems as well as SPR gas sensing measurements using laser ellipsometry as the detector. Further, an Infrared reflectometry / ellipsometry experiment will be built and used to study the adsorbed gas layer and the chemisorption process in the Fe:SnO2 / CO sensing system.

• DFG Programme: Research Grants
• International Connection: Czech Republic
• Partner Organisation: Czech Science Foundation
• Participating Person: Dr. Martin Kormunda