Valence band offset in heterojunctions between crystalline silicon and amorphous silicon (sub)oxides (a-SiO{sub x}:H, 0 < x < 2)

Journal Article · Mon Jan 19 00:00:00 EST 2015 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4906195· OSTI ID:22415126

Liebhaber, M.; Mews, M.; Schulze, T. F.; Rech, B.; Lips, K. ^[1]

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1. Institute Silicon Photovoltaics, Helmholtz-Zentrum Berlin für Materialien und Energie, Kekuléstr. 5, D-12489 Berlin (Germany)

The heterojunction between amorphous silicon (sub)oxides (a-SiO{sub x}:H, 0 < x < 2) and crystalline silicon (c-Si) is investigated. We combine chemical vapor deposition with in-system photoelectron spectroscopy in order to determine the valence band offset ΔE{sub V} and the interface defect density, being technologically important junction parameters. ΔE{sub V} increases from ≈0.3 eV for the a-Si:H/c-Si interface to >4 eV for the a-SiO{sub 2}/c-Si interface, while the electronic quality of the heterointerface deteriorates. High-bandgap a-SiO{sub x}:H is therefore unsuitable for the hole contact in heterojunction solar cells, due to electronic transport hindrance resulting from the large ΔE{sub V}. Our method is readily applicable to other heterojunctions.

• OSTI ID: 22415126
• Journal Information: Applied Physics Letters, Vol. 106, Issue 3; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BAND THEORY
CHEMICAL VAPOR DEPOSITION
GRADED BAND GAPS
HETEROJUNCTIONS
HYDROGEN
PHOTOELECTRON SPECTROSCOPY
SILICON
SILICON OXIDES
SOLAR CELLS