Ion Energy Threshold in Low-Temperature Silicon Epitaxy for Thin-Film Crystalline Photovoltaics

Author

Bruneau, Bastien ; Cariou, Romain ; Dornstetter, Jean-Christophe ; Lepecq, Michael ; Maurice, Jean-Luc ; Roca i Cabarrocas, Pere ; Johnson, Erik V.

Author_Institution

Lab. de Phys. des Interfaces et des Couches Minces, Ecole Polytech., Palaiseau, France

Volume

4

Issue

6

fYear

2014

fDate

Nov. 2014

Firstpage

1361

Lastpage

1367

Abstract

Plasma-enhanced chemical vapor deposition (PECVD) enables epitaxial silicon deposition for up to several micrometers and at low temperatures (as low as 150 °C). We present herein a detailed study of the effect of ion energy at high (above 2 torr) and low (below 1 torr) pressure, where the plasma and surface reactions are expected to be different, i.e., driven, respectively, by high-order and low-order silane precursors. We find a sharp energy threshold at low pressure, above which no epitaxy can be obtained, but this threshold is relaxed at high pressure. The occurrence of epitaxy breakdown is studied and compared in detail for these two different pressure regimes.

Keywords

elemental semiconductors; plasma CVD; semiconductor epitaxial layers; semiconductor growth; silicon; solar cells; surface chemistry; thin film devices; vapour phase epitaxial growth; PECVD; Si; epitaxy breakdown; high-order silane; ion energy threshold; low-order silane; low-temperature silicon epitaxy; plasma-enhanced chemical vapor deposition; sharp energy threshold; surface reaction; thin-film crystalline photovoltaic; Chemical vapor deposition; Crystalline materials; Diffraction; Epitaxial growth; Plasma temperature; Silicon; Epitaxy; ion energy; low temperature; plasma-enhanced chemical vapor deposition (PECVD); plasmaenhanced chemical vapor deposition (PECVD); silicon; solar cells; tailored voltage waveform;

fLanguage

English

Journal_Title

Photovoltaics, IEEE Journal of

Publisher

ieee

ISSN

2156-3381

Type

jour

DOI

10.1109/JPHOTOV.2014.2357256

Filename

6912925