Study on the Ozone Gas Sensing Properties of rf-Sputtered Al-Doped NiO Films

Featured Application Authors are encouraged to provide a concise description of the specific application or a potential application of the work. This section is not mandatory. Al-doped NiO (NiO:Al) has attracted the interest of researchers due to its excellent optical and electrical properties. In this work, NiO:Al films were deposited on glass substrates by the radio frequencies (rf) sputtering technique at room temperature and they were tested against ozone gas. The Oxygen content in (Ar-O-2) plasma was varied from 2% to 4% in order to examine its effect on the gas sensing performance of the films. The thickness of the films was between 160.3 nm and 167.5 nm, while the Al content was found to be between 5.3 at% and 6.7 at%, depending on the oxygen content in plasma. It was found that NiO:Al films grown with 4% O-2 in plasma were able to detect 60 ppb of ozone with a sensitivity of 3.18% at room temperature, while the detection limit was further decreased to 10 ppb, with a sensitivity of 2.54%, at 80 degrees C, which was the optimum operating temperature for these films. In addition, the films prepared in 4% O-2 in plasma had lower response and recovery time compared to those grown with lower O-2 content in plasma. Finally, the role of the operating temperature on the gas sensing properties of the NiO:Al films was investigated.

Automated summary

This study deposited NiO:Al films on glass substrates at room temperature using RF sputtering and tested their gas sensing performance against ozone gas. Films grown with 4% oxygen content in plasma showed better detection sensitivity and shorter response and recovery time, indicating their potential for gas sensing applications.