A near‐field scanning optical microscopy study of the photoluminescence from GaN films

We have achieved spatially resolved photoluminescence from GaN films using a near‐field scanning optical microscope (NSOM). GaN films grown by hydride vapor phase epitaxy (HVPE) and metal‐organic vapor phase epitaxy (MOVPE) on sapphire substrates have been studied. We have performed spatial scans of topography, band edge, and yellow luminescence signals. Atomic force microscopy measurements were also made and compared with the NSOM topography. We have found spatial variations in photoluminescence characteristics at the submicron scale for both HVPE and MOVPE GaN. The observed enhancement of yellow luminescence at multiatomic step edges on the HVPE GaN surface suggests that the yellow luminescence is associated with chemical impurities incorporated during the growth of GaN films.

[1]  Fernando Ponce,et al.  Microstructure of GaN epitaxy on SiC using AlN buffer layers , 1995 .

[2]  Olson,et al.  Optically detected magnetic resonance of GaN films grown by organometallic chemical-vapor deposition. , 1995, Physical review. B, Condensed matter.

[3]  Toh-Ming Lu,et al.  Diffraction from Rough Surfaces and Dynamic Growth Fronts , 1993 .

[4]  K. Hiramatsu,et al.  Characterization of the Shallow and Deep Levels in Si Doped GaN Grown by Metal-Organic Vapor Phase Epitaxy , 1994 .

[5]  E. Betzig,et al.  Combined shear force and near‐field scanning optical microscopy , 1992 .

[6]  H. Amano,et al.  P-Type Conduction in Mg-Doped GaN Treated with Low-Energy Electron Beam Irradiation (LEEBI) , 1989 .

[7]  M. Skowronski,et al.  Open‐core screw dislocations in GaN epilayers observed by scanning force microscopy and high‐resolution transmission electron microscopy , 1995 .

[8]  E. Bauser,et al.  Dopant tracing of terrace growth in GaAs LPE layers , 1978 .

[9]  T. Kuech,et al.  A near‐field scanning optical microscopy study of the uniformity of GaAs surface passivation , 1996 .

[10]  J. Hutchby,et al.  Photoluminescence of ion‐implanted GaN , 1976 .

[11]  Jörg Neugebauer,et al.  Gallium vacancies and the yellow luminescence in GaN , 1996 .

[12]  Werner Wegscheider,et al.  Optical spectroscopy of a GaAs/AlGaAs quantum wire structure using near-field scanning optical microscopy , 1994 .

[13]  Toshio Ogino,et al.  Mechanism of Yellow Luminescence in GaN , 1980 .

[14]  G. Rozgonyi,et al.  A lateral microscopic growth model for heterogeneous impurity incorporation during Czochralski crystal growth , 1980 .

[15]  David P. Bour,et al.  Spatial distribution of the luminescence in GaN thin films , 1996 .

[16]  S. Nakamura,et al.  InGaN-Based Multi-Quantum-Well-Structure Laser Diodes , 1996 .

[17]  T. C. Mcgill,et al.  Halide Vapor Phase Epitaxy of Gallium Nitride Films on Sapphire and Silicon Substrates , 1995 .