In situ phosphorus-doped polycrystalline silicon films by low pressure chemical vapor deposition for contact passivation of silicon solar cells
| Autor: | Jef Poortmans, Meriç Fırat, Maria Recaman Payo, Filip Duerinckx, Hariharsudan Sivaramakrishnan Radhakrishnan, Loic Tous |
|---|---|
| Rok vydání: | 2022 |
| Předmět: |
Solar cells
Technology In situ doping Materials science Energy & Fuels Passivation Silicon LPCVD Analytical chemistry chemistry.chemical_element 02 engineering and technology Chemical vapor deposition engineering.material 010402 general chemistry 01 natural sciences Phosphorus doping Electrical resistivity and conductivity General Materials Science Science & Technology DISILANE Dopant Renewable Energy Sustainability and the Environment Doping 021001 nanoscience & nanotechnology 0104 chemical sciences Polycrystalline silicon chemistry Passivating contacts Polysilicon engineering 0210 nano-technology Short circuit |
| Zdroj: | Solar Energy. 231:78-87 |
| ISSN: | 0038-092X |
| DOI: | 10.1016/j.solener.2021.11.045 |
| Popis: | In situ phosphorus (P)-doped polycrystalline silicon (poly-Si) films by low pressure chemical vapor deposition (LPCVD) were studied in this work for the fabrication of poly-Si passivating contacts. In situ doping was targeted for enabling the full potential of the high-throughput LPCVD technique, as it could allow leaner fabrication of industrial solar cells featuring poly-Si passivating contacts than the more common ex situ doping routes. By careful optimization of the deposition temperature and the flows of the carrier gas (H-2) and the dopant precursor (PH3), high doping in the poly-Si layers was achieved with active P concentrations up to 1.3.10(20) cm(-3) . While reduction in the deposition rate (r(dep)) and thus in the throughput is a known problem when growing in situ P-doped films by LPCVD, this reduction could be limited, and the resulting r(dep) was equal to 0.078 nm/s. The developed poly-Si films were characterized both structurally and in terms of their passivation potential in poly-Si contacts. The latter yielded recombination current densities down to 1.5 fA/cm(2) in passivated (J(0, p)) and 25.6 fA/cm(2) in screen-printing metallized (J(0, m)) regions on saw-damage removed (SDR) Cz-Si surfaces, accompanied by a contact resistivity (rho(c,m)) of 4.9 m Omega.cm(2). On textured Cz-Si surfaces, the corresponding values were J(0, p) = 3.5 fA/cm(2), J(0,m )= 56.7 fA/cm(2), and rho(c,m) = 1.8 m Omega.cm(2). Optical impact of the developed poly-Si films was also assessed and a short circuit density loss of 0.41 mA/cm(2) is predicted per each 100 nm of poly-Si applied at the rear side of solar cells. The authors would like to acknowledge Rajiv Sharma from KU Leuven for his help with the interfacial oxide development, Sukhvinder Singh and Patrick Choulat from Imec for their help with the contact resistivity measurements and sample fabrication, Thomas Nuytten and Stefanie Sergeant from Imec for the Raman spectroscopy measurements, Bastien Douhard and Mustafa Ayyad from Imec for SIMS measurements, Maxim Korytov, Laura Nelissen, and Patricia van Marcke from Imec for the TEM specimen preparation and measurements, and Janusz Bogdanowicz from Imec for his help with the analysis of the Hall measurement data. This work was supported by the European Union’s Horizon2020 Programme for research, technological development, and demonstration [grant number 857793]; and by the Kuwait for the Advancement of Sciences [grant number CN18-15EE-01]. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect