Abstract: | GaN crystals were prepared by heating a Ga melt with 1 at% Li3N against Ga at 750 °C in Na vapor under N2 pressures of 0.4–1.0 MPa. The GaN crystals grown at 1.0 MPa of N2 were colorless and transparent prismatic, having a size of approximately 0.7 mm in length. A secondary ion mass spectrometry (SIMS) showed the contaminant of lithium in the obtained crystals. A large broad yellow band emission peak of 2.28 eV was observed at room temperature in the photoluminescence spectrum in addition to the near band emission peak of GaN at 3.39 eV and a small broad satellite emission at 3.24 eV. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) |