@article{Yang2025, 
author = {Lei Yang and Yali Ou and Xiang Lv and Na Lin and Yuheng Zeng and Zechen Hu and Shuai Yuan and Jichun Ye and Xuegong Yu and Deren Yang},
title = {Enhanced Passivation Effect of Tunnel Oxide Prepared by Ozone-Gas Oxidation (OGO) for n-Type Polysilicon Passivated Contact (TOPCon) Solar Cells},
year = {2025},
journal = {Energy & Environmental Materials},
volume = {8},
number = {1},
keywords = {interface states, ozone-gas oxidation, silicon solar cells, tunnel oxide passivation contact (TOPCon)},
url = {https://www.sciopen.com/article/10.1002/eem2.12795},
doi = {10.1002/eem2.12795},
abstract = {Nowadays, a stack of heavily doped polysilicon (poly-Si) and tunnel oxide (SiOx) is widely employed to improve the passivation performance in n-type tunnel oxide passivated contact (TOPCon) silicon solar cells. In this case, it is critical to develop an in-line advanced fabrication process capable of producing high-quality tunnel SiOx. Herein, an in-line ozone-gas oxidation (OGO) process to prepare the tunnel SiOx is proposed to be applied in n-type TOPCon solar cell fabrication, which has obtained better performance compared with previously reported in-line plasma-assisted N2O oxidation (PANO) process. In order to explore the underlying mechanism, the electrical properties of the OGO and PANO tunnel SiOx are analyzed by deep-level transient spectroscopy technology. Notably, continuous interface states in the band gap are detected for OGO tunnel SiOx, with the interface state densities (Dit) of 1.2 × 1012–3.6 × 1012 cm−2 eV−1 distributed in Ev + (0.15–0.40) eV, which is significantly lower than PANO tunnel SiOx. Furthermore, X-ray photoelectron spectroscopy analysis indicate that the percentage of SiO2 (Si4+) in OGO tunnel SiOx is higher than which in PANO tunnel SiOx. Therefore, we ascribe the lower Dit to the good inhibitory effects on the formation of low-valent silicon oxides during the OGO process. In a nutshell, OGO tunnel SiOx has a great potential to be applied in n-type TOPCon silicon solar cell, which may be available for global photovoltaics industry.}
}