Electronic Devices Ratka Neshkovska, Mimoza Ristova and Julijana Velevska 11 1 2022 https://doi.org/10.6025/ed/2022/11/1/17-21 https://www.dline.info/ed/fulltext/v11n1/edv11n1_3.pdf In this study we have deposited the electrochromic copper oxide files for conductive glass substrates with electrochemical analysis. We have organized the electrochemical test device using aqueous solution. We have recorded the observations from the reflectance spectral of the films in various states.