Author/Authors :
Malissa، H. نويسنده , , Jantsch، W. نويسنده , , Przybylinska، H. نويسنده , , Bonanni، A. نويسنده , , Wolos، A. نويسنده , , Kiecana، M. نويسنده , , Sawicki، M. نويسنده , , Dietl، T. نويسنده , , Simbrunner، C. نويسنده , , Wegscheider، M. نويسنده , , Sitter، H. نويسنده , , Rumpf، K. نويسنده , , Granitzer، P. نويسنده , , Krenn، H. نويسنده ,
Abstract :
We report on metal-organic chemical vapour deposition growth of GaN:Fe and its characterization by means of high-resolution X-ray diffraction, secondary ion mass spectroscopy, electron spin resonance, and magnetization measurements. Electron spin resonance studies demonstrate the existence of Fe in the isolated 3d5 (Fe^3+) state. Magnetic measurements reveal, apart from Curie paramagnetism due to Fe^3+, a temperature independent contribution which we attribute tentatively to van Vleck paramagnetism of Fe in the 2+ state. We conclude that the Fe ions coexist in two charge states in the investigated samples. The fraction of Fe^3+ ions was found to increase upon additional co-doping with Mg acceptors, both in ESR as well as in magnetization measurements.
