钝化接触高效晶硅电池 - 异 质结、TopCon 及其它（东方日升首席科学家万义茂）

Passivating Contacts: theory and applications Yimao Wan Ph.D Chief Scientist 7/12/2019 Conceptualisation of PV devices 2U. Würfel, A. Cuevas and P. Würfel, IEEE JPV (2015) Passivating contacts: carrier selectivity concept 3 Carrier selectivity: • Selective collection of one carrier type at the contact How to measure it: • Contact recombination J0c • Contact resistivity ρc How do we achieve it: • Heavy doping passivating contacts – Directly metalized doped Si – Doped polysilicon – Doped amorphous silicon • Dopant free passivating contacts – Salts, carbonates, TMO, organic, and etc. Passivating contacts mechanism 4Allen et al. Nature Energy 2019 • Doped polysilicon • Doped amorphous silicon • Dopant free passivating contacts: Salts, carbonates, TMO, organic, and etc. State-of-the-art: Directly metalized diffused silicon 5Bullock J., Ph.D thesis., 2016 Contact resistivity ρc • Screen P ~1 mΩcm2 • Evap ~0.001 mΩcm2 State-of-the-art: Directly metalized diffused silicon 6 • Contact resistivity ρc • Screen P ~1 mΩcm2 • Evap ~0.001 mΩcm2 • Contact recombination J0c ~350 fA/cm2 Bullock J., Ph.D thesis., 2016 Directly metalized application: PERC, PERL, SE 7 Screen PEvap Bullock J., Ph.D thesis., 2016 J. Zhao et al. / Solar Energy Materials Solar Cells 66 (2001) 27-36 • Diffusion • SE • Metal paste • Screen PERL UNSW: 25% State-of-the-art: doped polysilicon passivating contacts 8Yan D., Ph.D thesis., 2016 • ρc ~10 mΩcm2 • J0c : ~1–20 fA/cm2 Doped polysilicon application: TOPCON, POLO-IBC … 9 Screen PEvap Bullock J., Ph.D thesis., 2016 Richter et al. SolMat 2017 Yan et al. APL 2018 PolySi P-type TOPCON ANU: 23% N-type TOPCON F-ise 25.7% Doped amorphous silicon application: HJT, HBC … 10 Screen PEvap Bullock J., Ph.D thesis., 2016 PolySi a-Si HJT Hanergy: 25.11% Dopant-free carrier-selective passivating contacts 11Allen et al. Nature Energy 2019 • Getting the extreme work function to work • Mechanisms include introducing asymmetric work functions, band offsets, tunnelling probabilities and more (mobility, defects etc.) • A very wide range of materials: Oxides, fluorides, nitrides, organic materials etc. with a strong electron or hole collecting capability Dopant-free passivating contacts: case study 12 A growing family of dopant-free passivating contacts 13 Dopant-free passivating contacts application: nPERC, DASH… 14Bullock J., Ph.D thesis., 2016 First N-type PERC: 23.1% DASH: 20.7% Dopant-free passivating contacts applications: Perovskite 15 Regular structure –TiO2 ETL Inverted structure –NiOx HTL Dopant-free passivating contacts applications: Perovskite/Si tandem … 16 Wu et al. En. En. Sci. 2017 ITO/Metal/diffused Si ANU: 22.7% Dopant-free passivating contact ANU: 23.2% Doped Si passivating contacts EPFL: 25.2% Sahli et al. Nat. Mat. 2018 He et al. Sci. Adv. 2018 Cell Technology Roadmap Tandem ~ 29% 17 Risen 2020: 1. PERC with Polysilicon 2. HJT 2020: Year of “Passivating Contacts”( 钝化接触元年 ) ➢ Upgrade PERC with passivating contacts ➢ Heterojunction with thin a-Si (HJT) Cell efficiency roadmap 21.92% 22.19% 22.38% 22.50% 22.80% 23.00% 23.20%23.20% 23.50% 24.00%23.50% 24.00% 24.50% 2019Q1 2019Q2 2019Q3 2019Q4 2020H1 2020H2 2021 PERC PERC+TOPCON HJT THE POWER OF RISING VALUE www.risenenergy.com Thanks!