https://doi.org/10.1051/epjap:2004043
Cathodoluminescence microanalysis of porous GaP and InP structures
1
Laboratory of Low-Dimensional Semiconductor Structures,
Institute of Applied Physics, Technical University of Moldova,
MD-2004 Chisinau, Moldova
2
Department of Materials Science, Faculty of Engineering,
Christian-Albrechts University,Keiserstr. 2, D-24143 Kiel, Germany
3
School of Physics, University of NSW Sydney, NSW 2052, Australia
Corresponding author: tiginyan@mail.utm.md
Received:
25
September
2003
Accepted:
28
January
2004
Published online: 15 July 2004
Electron microscopy and cathodoluminescence (CL) microanalysis
were used for a comparative study of porous layers fabricated
by electrochemical etching of n-GaP and n-InP substrates in aqueous
solutions of sulfuric and hydrochloric acids. Both the CL and
morphology of porous layers were found to depend upon the anodic
current density. At high current density (100 mA/cm2) anodization
leads to the formation of so-called current-line oriented pores
while at low current densities the pores grow along 
crystallographic directions. The porosity relief was found to
give rise to spatial modulation of the CL intensity. The composition
microanalysis proved the stoichiometry of porous GaP and InP
skeletons, although we found considerable traces of oxygen in
porous GaP layers. Self-induced voltage oscillations giving rise
to a synchronous modulation of the diameter of pores and CL intensity
were evidenced.
PACS: 68.37.Hk – Scanning electron microscopy (SEM) (including EBIC) / 78.60.Hk – Cathodoluminescence, ionoluminescence / 81.07.Bc – Nanocrystalline materials
© EDP Sciences, 2004
