Contact: Prof. D.N. (Noel) Buckley
Chair of Physics, University of Limerick
Compound semiconductors such as InP and GaN are the materials basis for many photonic and advanced microelectronic devices. Periodic structures in these materials have possible applications in photonic bandgap devices for ultra-fast optical communications. The Compound Semiconductor Materials and Nanostructures group within the Physics Department and Materials & Surface Science Institute (MSSI) studies nanoscale pore formation in compound semiconductors by means of electrochemical and photoelectrochemical etching and this has emerged as a very promising technique for tailoring the properties of semiconductors.
Modulation of the pore diameter and direction could allow for the fabrication of devices based on photonic crystal structures. The work includes nanostuctural characterization using atomic force (AFM) and scanning tunnelling (STM) microscopy, high resolution transmission and scanning electron microscopy (TEM and SEM), potential-dependant photoluminescence (PDPL) and a variety of electroanalytical, electrical and spectroscopic techniques as well as microelectronics fabrication techniques. The group provides a knowledge base for technological development and specialized postgraduate training.
The group has dedicated state-of-the-art facilities for nanostructural characterization including a VEECO Enviroscope scanning probe microscope, a Hitachi S-4800 high resolution field emission SEM, and a range of equipment for electroanalytical, electrical, optical and mechanical measurements. An excellent range of other techniques is available within the MSSI including TEM, XPS, XRD, DSC, SIMS and ellipsometry.
The group leader, Prof. Noel Buckley has over 30 years of research experience including 17 years at Bell Laboratories (Murray Hill, NJ, USA). He is Vice-President and Fellow of The Electrochemical Society and for many years was an editor of The Journal of the Electrochemical Society and Electrochemical and Solid State Letters.
Cross-sectional TEM image of a nanoporous domain formed during anodic etching of n-InP in 5 mol dm-3 KOH. (right) AFM image showing surface features formed during photoelectrochemical etching of n-GaN in 1 mol dm-3 H3PO4.
“In-situ Observation of Photo Controlled Electrochemical Etching of n-InP”, Lynch R. P. (University of Limerick, Ireland), Dornhege M. (Fritz-Haber-Institut der Max-Planck-Gesellschaft, Berlin, Germany), Rotermund H. (Dalhousie University, Halifax, Nova Scotia, Canada) and Buckley D. N., Symposium on Processes at the Semiconductor Solution Interface II, 211th Meeting of the Electrochemical Society, Chicago, Illinois, Abstract No. 612, May 6-10, 2007.
“Directions of Pore Propagation and Porous Domain Shape in n-InP Anodized in KOH” , Lynch R. P. ,O’ Dwyer C., Sutton D., Newcomb S. and Buckley D. N., Symposium on Processes at the Semiconductor Solution Interface II, 211th Meeting of The Electrochemical Society, Chicago, Illinois, Abstract No. 614, May 6-10, 2007.
“In-situ Observation of Pore Formation and Photoelectrochemical Etching in n-InP”, Lynch R., Dornhege M., Bodega P. Sánchez, Rotermund H.H. and Buckley D.N. , ECS Transactions, 6(2), 331-343, May (2007).
“Nanoporous Domains in n-InP Anodized in KOH”, LynchR., O’Dwyer C., Sutton D., Newcomb S., and Buckley D. N. , ECS Transactions, 6(2), 355-366, May (2007).
“An Investigation by AFM and TEM of the Mechanism of Anodic Formation of Nanoporosity in n-InP in KOH”, O’Dwyer C., Buckley D. N., Sutton D., Serantoni M., and Newcomb S. B. , Journal of the Electrochemical Society, 154, H78- H85, December,14 (2007).
“Anodic Formation and Characterization of Nanoporous InP in Aqueous KOH Electrolytes”, O’Dwyer C., Buckley D. N., Sutton, D. and Newcomb, S. B. , Journal of the Electrochemical Society, 153, G1039- G1046, October (2006).
“Effect of Electrolyte Concentration on Anodic Nanoporous Layer Growth for n-InP in Aqueous KOH”, Lynch Robert, O’Dwyer Colm, Buckley D. N., Sutton David and Newcomb Simon, ECS Transactions, 2, 131-141, May (2006).