Berlin 2012 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

HL: Fachverband Halbleiterphysik

HL 25: Poster Session: GaN - Optical Properties & Preparation and Characterization & Devices

HL 25.22: Poster

Montag, 26. März 2012, 16:00–19:00, Poster D

Implantation studies on silicon doped group-III nitride semiconductors — Ronnie Simon¹, •Reiner Vianden¹, and Klaus Köhler² — ¹Helmholtz-Institut für Strahlen- und Kernphysik, Universität Bonn — ²Fraunhofer Institut für angewandte Festkörperphysik, Freiburg

Silicon doped GaN layers grown by low-pressure metal-organic vapor-phase epitaxy with Si concentrations ranging from 2*10¹⁷ atoms/cm³ to 9.2*10¹⁸ atoms/cm³ were investigated by means of the perturbed angulat correlation (PAC) technique applied to implanted ¹¹¹In(Cd). An undoped GaN film is used as a reference. The Si-atoms replace Ga-atoms in the lattice and silicon, being a group-IV element, acts as a donor on the Ga-site and contributes one extra electron to the conduction band. Hall effect measurements confirmed that the free charge carrier density is essentially increased and of the order of the silicon concentration. PAC investigations of the annealing behavior after implantation of the ¹¹¹In probes shows that best recovery is achieved after annealing at 1200 K and that high silicon concentrations make GaN films more stable at high temperatures. Further, it was found that the temperature dependence of the electric field gradient is reduced by increasing Si concentrations.