## 6 Conclusions  
In this study, we present a novel solar-blind SAW UV-C sensor system utilizing HfO\({}_{2}\) as sensing material, accompanied by newly developed sensor interface electronics. The HfO\({}_{2}\) thin film was deposited using ALD, with the deposition process explained in detail. The effect of annealing temperature was thoroughly investigated, and 500 \({}^{\circ}\)C was identified as the optimal temperature. Additionally, the study examines the influence of HfO\({}_{2}\) film thickness on the sensor's UV-C response. The sensor's characterization was systematically performed in a controlled and stable environment, with effective compensation for external factors such as temperature and humidity. This was achieved using a reference device  
Figure 12: (**a**) Schematic illustration for detecting corona discharge in a simulated environment, (**b**) real-time testing capture of the corona discharge environment and sensor position, (**c**) sensor response to corona discharge at a 10 cm distance, and (**d**) at 20 cm distance. integrated with the same SAW UV-C sensor design based on HfO\({}_{2}\). The sensor demonstrated excellent repeatability in measurements and reliability throughout a month-long testing period. Furthermore, it exhibited outstanding selectivity to UV-C, making it highly suitable for applications in the solar-blind UV-C range. Finally, a real-field experiment was conducted to validate the feasibility of the developed sensor in practical applications for detecting corona discharge. The presented sensor shows significant potential for a wide range of fields requiring solar-blind UV-C detection. Experimental Equipment and UV-C Light SourcesThe LED and UV-C source used in this study is \"U01-133-208 UV Handy Lamp/ 1 \(\times\) 6 Watt, 312/254 nm, intensity: 580/400 ea\", manufactured and sold by \"LK LAB located in Namyangju, South Korea\" for 312 nm and 254 nm. LED (220 nm) \"UWF222-2W\", manufactured and sold by \"Zhengzhou UVwave Electronic Technology Co., Ltd. located in Zhengzhou City, Henan Province, in the middle part of China\". The UV light meter was model \"YK-37 UVSD\", manufactured by \"Lutron Instruments located in Sungnam City, South Korea\". H.L. : Conceptualization, methodology, data curation, formal analysis, writing--original draft. F.N. : conceptualization, methodology, data curation, formal analysis, writing--original draft. E.S. : data curation, formal analysis. J.L. : data curation, formal analysis. C.C. : data curation, funding acquisition. K.L. : conceptualization, methodology, writing--original draft, project administration, funding acquisition. All authors have read and agreed to the published version of the manuscript. This research was funded by Korea Electric Power Corporation under Grant R22X002-17, in part by the Ministry of Science and ICT (RS-2023-00278288), and in part by the National Research Foundation of Korea (2023K2A9A1A01098852 and RS-2023-00278288). Not applicable. Data Availability StatementData will be made available on request. The authors declare that this study received funding from KEPCO. The funder was not involved in the study design, collection, analysis, interpretation of data, the writing of this article or the design to submit it for publication. References  
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