Autori: Enrique Garralaga Rojas, Barbara Terheiden, Heiko Plagwitz, Carsten Hampe, Daniel Tutuc, Rolf J. Haug, Rolf Brendel
Editorial: Physica Status Solidi A, 206, p.2872-2875, 2009.
Mesoporous GaAs double layers with different porosities and
thicknesses up to 7 m are formed on highly doped p-type
4 inch GaAs substrates by means of electrochemical etching in
highly concentrated hydrofluoric acid electrolytes. Small 111
oriented pyramids form at the interface between porous layer
and substrate if etching current densities below 7.5mAcm−2
are applied. Porous double layers with different porosities
are obtained by varying simultaneously the etching current
density and the electrolyte concentration. The porosity of the
porous GaAs layers decreases nearly linearly from 69 to 53%
with electrolyte concentrations increasing from 30 to 50 wt.%,
respectively. The etching process increases the mean roughness
of the porous layer surface from 0.15 to 0.24 nm.
Cuvinte cheie: Porous materials, GaAs, surface etchnig, photoelectric conversion