1. Metal-induced gap states in passivating metal/silicon contacts.
- Author
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Sajjad, Muhammad, Yang, Xinbo, Altermatt, Pietro, Singh, Nirpendra, Schwingenschlögl, Udo, and De Wolf, Stefaan
- Subjects
PASSIVATION ,SILICON ,METALS ,SURFACE defects ,DENSITY functional theory - Abstract
Passivating metal/silicon contacts combine low carrier recombination with low contact resistivities, enabled by a low gap state density at their interface. Such contacts find applications in high-efficiency solar cells. We perform first-principles calculations based on density functional theory to investigate the surface defect and metal-induced gap state density of silicon in close contact with metals (Al and Ag). We confirm that surface hydrogenation fully removes surface-defect gap states of (111)-oriented silicon surfaces. However, the metal-induced gap state density increases significantly when metals are closer than 0.5 nm to such surfaces. These results highlight the importance of the tunneling-film thickness in achieving effective passivating-contact formation. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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