A1 Journal article (refereed)
Thermal atomic layer deposition of AlOxNy thin films for surface passivation of nano-textured flexible silicon (2019)

Parashar, P. K., Kinnunen, S., Sajavaara, T., Toppari, J., & Komarala, V. K. (2019). Thermal atomic layer deposition of AlOxNy thin films for surface passivation of nano-textured flexible silicon. Solar Energy Materials and Solar Cells, 193, 231-236. https://doi.org/10.1016/j.solmat.2019.01.019

JYU authors or editors

Kinnunen, Sami
Sajavaara, Timo
Toppari, Jussi

Publication details

All authors or editors: Parashar, Piyush K.; Kinnunen, Sami; Sajavaara, Timo; Toppari, Jussi; Komarala, Vamsi K.

Journal or series: Solar Energy Materials and Solar Cells

ISSN: 0927-0248

eISSN: 1879-3398

Publication year: 2019

Volume: 193

Issue number: 0

Pages range: 231-236

Publisher: Elsevier BV

Publication country: Netherlands

Publication language: English

DOI: https://doi.org/10.1016/j.solmat.2019.01.019

Publication open access: Not open

Publication channel open access:

Abstract

Aluminum oxynitride (AlOxNy) films with different nitrogen concentration are prepared by thermal atomic layer deposition (ALD) for flexible nano-textured silicon (NT-Si) surface passivation. The AlOxNy films are shown to exhibit a homogeneous nitrogen-doping profile and the presence of an adequate amount of hydrogen, which is investigated by Time-of-Fight Elastic Recoil Detection Analysis (ToF-ERDA). The effective minority carrier lifetimes are measured after the NT-Si surface passivation; the minimum surface recombination velocity (SRV) of 5 cm-s−1 is achieved with the AlOxNy film in comparison to the Al2O3 and AlN films (SRV of 7–9 cm-s−1). The better SRV with AlOxNy film is due to the collective effect of field-effect passivation by the presence of fixed negative charges, and chemical passivation by the presence of hydrogen within the film. The capacitance-voltage, and conductance measurements also are carried out using metal-oxide-semiconductor structure to determine the fixed negative charge density (Ni,ox), and defect density of states (Dit) in the AlOxNy films. The better surface passivation is attributed to unusually large Ni,ox of ~6.07 × 1012 cm−2, and minimal Dit of ~1.01 × 1011 cm−2-eV−1 owing to the saturation of Si dangling bonds by the hydrogen within the AlOxNy film matrix after the annealing step.

Keywords: atomic layer deposition; thin films; nanostructures; silicon; aluminium

Free keywords: black flexible silicon; aluminum oxynitride; surface passivation; thermal atomic layer deposition; time-of-flight elastic recoil detection analysis (ToF-ERDA)

Fields of science: