Abstract
ZnO nanopillars were successfully grown using both the vapor-liquid-solid and the aqueous chemical growth methods on different substrates, such as quartz, n-, and p-type non-porous Si wafer (flat) and microporous periodic Si structure (MPSiS). Scanning electron microscopy was employed to compare sample morphologies. The absorption was calculated employing the GW 0 method, based on the local density approximation, and with the projector augmented wave approach. Experiment and theory show a reasonable agreement when the shape of the optical absorption is considered. The measured absorption of ZnO nanopillars, on different substrates, is lower than that observed for ZnO films on quartz substrate, in the energy gap spectral range. A strong effect of MPSiS substrates on ZnO nanopillar properties is observed. The photoluminescence technique was also employed as an optical characterization.
Original language | English |
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Article number | 123527 |
Journal | Journal of Applied Physics |
Volume | 111 |
Issue number | 12 |
DOIs | |
State | Published - 15 Jun 2012 |
Bibliographical note
Funding Information:The authors acknowledge the financial support of the Brazilian agencies FAPESB and CNPQ, the Swedish Energy Agency (STEM), the Swedish Research Council (VR), the European EM ECW EUBRANEX Programme, and the computers centers PDC/NSC via SNIC/SNAC. We thank Ångström Solar Center at Uppsala University, Sweden that provided the absorption data from Fig. of Ref. to our Fig. .