Akademik Veri Yönetim Sistemi
International Conference on Natural Science and Technologies (ICONAT'23), Burgas, Bulgaristan, 1 - 03 Haziran 2023, ss.16
In this study, effects of selective citric acid solution on the surface properties of p-n junction solar cells were investigated and analyzed. Solar cell structures were grown by molecular beam epitaxy (MBE) system and cut into small pieces with a size of 0.5 × 0.5 cm2 for a detailed etch study. First of all, the samples were cleaned sequentially in acetone, isopropanol (at 80°C), and distilled water for a duration of 5 minutes and then dried with N2 flow. Following the cleaning procedure, the native oxide on the samples was removed in HCl acid solution at a ratio of (H2O) 5:1 (HCl) in 20-25 seconds. After oxide removal, samples surfaces were coated with a photoresist (AZ 5214E) using a spin coating system at 3000 rpm for 40 seconds and then pre-cured at 110°C on a hot plate. Mesa patterns were transferred onto the samples using a photo-lithography system. After UV exposure, mesa patterns appeared in the developer solution (AZ400K: H2O; 1:4) and the samples were cured again at 120 °C for 5 minutes on a hot plate. The photoresist thickness of each sample was measured using a profilometer. Afterward, a mixture of citric acid and water was prepared at a ratio of 1:1, and a solution of citric acid was prepared by mixing the prepared mixture with H2O2 at a ratio of 1:5. The samples were kept in this prepared citric acid solution for 30, 60, 90 or 120 seconds. Etch depths were measured using a profilometer and an etching graph was formed. Surface photographs were taken before and after citric acid treatment and the effects of etching on the surface were examined.