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

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.
Authors:
; ; ; ; ;  [1]
  1. Institute Silicon Photovoltaics, Helmholtz-Zentrum Berlin für Materialien und Energie, Kekuléstr. 5, D-12489 Berlin (Germany)
Publication Date:
OSTI Identifier:
22415126
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 106; Journal Issue: 3; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; BAND THEORY; CHEMICAL VAPOR DEPOSITION; GRADED BAND GAPS; HETEROJUNCTIONS; HYDROGEN; PHOTOELECTRON SPECTROSCOPY; SILICON; SILICON OXIDES; SOLAR CELLS