Paper NS+HC+SS-MoA9
Evaluation of Titanium Doped β-Ga₂O₃ Thin Films in Extreme Environment for Application in Oxygen Sensors

Monday, October 30, 2017, 4:20 pm, Room 19

The reliable and efficient operation of power generation systems has become one of the grand challenges of today’s research in order to meet the ever-increasing demand for energy and sustainability. The improvement in power/energy generation processes, in particular, for those depend on fossil fuels, the higher temperature and accurate measurement of the combustion environment and the emissions produced by the combustion via proper selection of sensing materials can enhance the efficiency and reliability. While several candidate metal oxides (SnO₂, ZnO, TiO₂, WO₃, and Ga₂O₃) exhibit high sensitivity chemical gases, β-Ga₂O₃ has shown to function as oxygen sensor at high temperatures (>700°C). However, the response time and sensitivity must be improved in order to utilize them in practical applications. While improved sensor characteristics are seen in various metal/ion doped β-Ga₂O₃, fundamental understanding of the long term effects of high temperature exposure on the structure and properties of doped β-Ga₂O₃ films is missing at this time. However, such studies are quite important to predict the thermodynamic stability and performance in extreme environments. In this work, we performed a detailed study to understand the effect of extreme environment on titanium (Ti) doped β-Ga₂O₃. The real environment condition for sensor (>700°C) application were simulated to understand the effect of temperature on the crystal structure, mechanical properties, electronic properties and oxidation states of Ti doped β-Ga₂O₃. The results will be presented and compared with as prepared Ti doped β-Ga₂O₃ films in the context of utilizing these materials in oxygen sensor applications.