Type

Conference Proceedings

Authors

Simon B. Newcomb
Robert P. Lynch
Colm O'Dwyer
D. Noel Buckley

Subjects

Chemistry

Topics
porous inp layers afm measurement inp substrates aqueous koh transmission electron microscopy tem electrochemistry nanoporous inp materials science

Formation of nanoporous InP by electrochemical anodization (2004)

Abstract Porous InP layers can be formed electrochemically on (100) oriented n-InP substrates in aqueous KOH. A nanoporous layer is obtainedunderneath a dense near-surface layer and the pores appear to propagatefrom holes through the near-surface layer. In the early stages of theanodization transmission electron microscopy (TEM) clearly showsindividual porous domains which appear to have a square-based pyramidalshape. Each domain appears to develop from an individual surface pitwhich forms a channel through this near-surface layer. We suggest that thepyramidal structure arises as a result of preferential pore propagationalong the <100> directions. AFM measurements show that the density ofsurface pits increases with time. Each of these pits acts as a source for apyramidal porous domain. When the domains grow, the current densityincreases correspondingly. Eventually, the domains meet forming acontinuous porous layer, the interface between the porous and bulk InPbecomes relatively flat and its total effective surface area decreasesresulting in a decrease in the current density. Numerical models of thisprocess have been developed. Current-time curves at constant potentialexhibit a peak and porous layers are observed to form beneath theelectrode surface. The density of pits formed on the surface increases withtime and approaches a plateau value.
Collections Ireland -> University College Cork -> Research Institutes and Centres
Ireland -> University College Cork -> Applied Nanoscience Group - Conference Items
Ireland -> University College Cork -> Tyndall National Institute
Ireland -> University College Cork -> Applied Nanoscience Group
Ireland -> University College Cork -> Chemistry
Ireland -> University College Cork -> College of Science, Engineering and Food Science
Ireland -> University College Cork -> Micro-Nanoelectronics Centre
Ireland -> University College Cork -> Chemistry - Conference Items

Full list of authors on original publication

Simon B. Newcomb, Robert P. Lynch, Colm O'Dwyer, D. Noel Buckley

Experts in our system

1
Robert P. Lynch
University of Limerick
Total Publications: 11
 
2
Colm O'Dwyer
University College Cork
Total Publications: 121
 
3
D. Noel Buckley
University College Cork
Total Publications: 27