Composition dependent growth dynamics in molecular beam epitaxy of GaInNAs solar cells




Arto Aho, Ville Polojärvia Ville-Markus Korpijärvi, Joel Salmi, Antti Tukiainen, Pekka Laukkanen, Mircea Guina

PublisherELSEVIER SCIENCE BV

AMSTERDAM; PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS

2014

Solar Energy Materials and Solar Cells

Solar Energy Materials and Solar Cells

Solar Energy Mater.Solar Cells

124

150

158

9

0927-0248

DOIhttps://doi.org/10.1016/j.solmat.2014.01.044



We have investigated the role of the nitrogen content, the growth parameters, and the annealing processes involved in molecular beam epitaxy of GaInNAs solar cells lattice-matched to GaAs. The nitrogen composition was varied between 1% and 5%. The influence of the growth temperature was assessed by performing photoluminescence, atomic force microscopy, X-ray diffraction, reflection high-energy electron diffraction, quantum efficiency and light-biased current-voltage measurements. The growth temperature ensuring the best cell parameters was found to be 440 degrees C. At this temperature we were able to incorporate up to 4% of nitrogen and achieve a good material quality. Further increase of the N composition to 5% led to phase separation. For the lattice matched samples grown within the optimal temperature range, we have identified a clear (1 x 3) surface reconstruction. Using the optimized growth we have demonstrated a GaInNAs p-i-n solar cell structure containing 4% nitrogen, that exhibited a short-circuit current density as high as 33.8 mA/cm(2) in respect to effective area illuminated. These measurements have been performed under real sun AM1.5 (similar to 1000 W/m(2)) illumination. (c) 2014 Elsevier B.V. All rights reserved.




Last updated on 2024-26-11 at 19:07