Wang, JialiTruong, ThienBalendhran, SivacarendranRen, JinleiAdier, MarieCreon, LauraPeres, PaulaChemnitzer, ReneCorre, Pierre YvesLi, ZhuofengNguyen, Hieu T.Yan, DiBullock, JamesStuckelberger, JosuaMacdonald, DanielLiu, AnYaoPhang, Sieu Pheng2026-01-022026-01-021944-8244PubMed:40296217ORCID:/0000-0001-5792-7630/work/197127721ORCID:/0000-0003-4579-5495/work/197129794ORCID:/0000-0002-5050-3082/work/216822420https://hdl.handle.net/1885/733802491Herein, we fabricate and characterize localized boron- and phosphorus-doped polycrystalline silicon (poly-Si)/SiOx passivating contacts for silicon solar cells by maskless inkjet printing technology with commercially sourced liquid dopant inks. Moreover, we leverage the advantages of inkjet printing to demonstrate the simultaneous formation of localized p+ and n+ poly-Si/SiOx passivating contact lines by a single anneal at 950 °C for 60 min. Optical microscopy images reveal well-defined dopant lines with features down to ∼60 μm. Microphotoluminescence (μPL) mapping confirms the enhanced surface passivation in the locally printed regions compared to the unprinted regions due to doping. In addition, high-resolution dynamic secondary ion mass spectrometry (SIMS) measurements quantify the total dopant concentrations in the lines, and electrochemical capacitance-voltage (ECV) was applied to measure the electrically active dopant concentrations in co-processed pads. The μPL and SIMS maps clearly reflect the line shapes from optical microscopy images, and exhibit sharp line features, irrespective of line widths or dopant species. More importantly, SIMS analysis highlights unintended doping in unprinted regions and cross-doping when both polarities are co-annealed. Introducing a thick spin-on SiOx protective layer in unprinted regions effectively mitigates unintended doping. Comparison of the μPL and SIMS maps suggests that the unintended doping arises from volatile dopant species released into the gas phase, rather than from the lateral diffusion of dopants. The benefits and limitations of the characterization methods are also discussed. These findings provide valuable insights for the further optimization of inkjet printing for localized doping of poly-Si/SiOx passivating contacts, particularly in interdigitated back contact solar cell architectures.This work has been supported by the Australian Renewable Energy Agency (ARENA) through projects 2017/RND017 and 2022/TRAC004. J.S. acknowledges support through an Australian Centre for Advanced Photovoltaics (ACAP) postdoctoral fellowship. Part of the fabrication for this work was performed at the Micro Nano Research Facility (MNRF) at RMIT University, in the Victorian Node of the Australian National Fabrication Facility (ANFF).13en© 2025 The Author(s)ex-situ dopinginkjet-printingliquid dopingpassivating contactsTOPCon2025-04-2810.1021/acsami.5c05734105003769763