Effect of screw dislocation density on optical properties in n-type wurtzite GaN

The effect of open-core screw dislocations on photoluminescence in n-doped wurtzite GaN epilayer is studied computationally and compared with experimental data. A k•p Hamiltonian calculation domain is set up to contain a dipole of open-core screw dislocations, and its size is varied according to the desired dislocation density. Using the finite element method, energy levels and wave functions for conduction and valence states are determined in three-dimensional real space; the emission spectrum is then evaluated. The void associated with the dislocation core and the deformation potential due to the strain surrounding the core perturb the density of states and reduce the photoluminescence (PL) spectrum intensity accordingly. For dislocation densities below a transition density of around 108cm−2, the deformation potential effect dominates in reducing the PL intensity; above this dislocation density the effect of the missing material at the core dominates. The calculated photoluminescence results agree with ...

[1]  Shuji Nakamura,et al.  High‐power InGaN single‐quantum‐well‐structure blue and violet light‐emitting diodes , 1995 .

[2]  F. Ponce,et al.  Electron holography studies of the charge on dislocations in GaN. , 2001, Physical review letters.

[3]  N. Browning,et al.  Role of oxygen at screw dislocations in GaN. , 2003, Physical review letters.

[4]  E. C. Carr,et al.  CORRELATION OF CATHODOLUMINESCENCE INHOMOGENEITY WITH MICROSTRUCTURAL DEFECTS IN EPITAXIAL GAN GROWN BY METALORGANIC CHEMICAL-VAPOR DEPOSITION , 1997 .

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

[6]  Shun Lien Chuang,et al.  k.p method for strained wurtzite semiconductors , 1996 .

[7]  T. Frauenheim,et al.  Effect of oxygen on the growth of (101̄0) GaN surfaces: The formation of nanopipes , 1998 .

[8]  Sven Öberg,et al.  Theory of Threading Edge and Screw Dislocations in GaN , 1997 .

[9]  Z. Liliental-Weber,et al.  Formation Mechanism of Nanotubes in GaN , 1997 .

[10]  J. H. You,et al.  Electron scattering due to threading edge dislocations in n-type wurtzite GaN , 2006 .

[11]  David C. Look,et al.  Dislocation Scattering in GaN , 1999 .

[12]  Robert J. Trew,et al.  High power applications for GaN-based devices , 1997 .

[13]  Desheng Jiang,et al.  Influence of dislocations on photoluminescence of InGaN∕GaN multiple quantum wells , 2005 .

[14]  Akito Kuramata,et al.  Photoluminescence Intensity and Spectral Distribution of GaN Films on SiC Substrates — The Dependence on Dislocation Density and Structure , 1999 .

[15]  J. Xie,et al.  Conductive atomic force microscopy study of MBE GaN films , 2006, SPIE OPTO.

[16]  David Cherns,et al.  Oxygen segregation to dislocations in GaN , 2005 .

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

[18]  Fernando Ponce,et al.  High dislocation densities in high efficiency GaN‐based light‐emitting diodes , 1995 .

[19]  Jin-Xing Shi,et al.  Influence of different types of threading dislocations on the carrier mobility and photoluminescence in epitaxial GaN , 2002 .

[20]  Sven Öberg,et al.  DEEP ACCEPTORS TRAPPED AT THREADING-EDGE DISLOCATIONS IN GAN , 1998 .

[21]  James S. Speck,et al.  Scanning capacitance microscopy imaging of threading dislocations in GaN films grown on (0001) sapphire by metalorganic chemical vapor deposition , 1998 .

[22]  J. H. Davies,et al.  The physics of low-dimensional semiconductors , 1997 .

[23]  I. Adesida,et al.  Gallium nitride whiskers formed by selective photoenhanced wet etching of dislocations , 1998 .

[24]  Takao Kuroda,et al.  Dependence of optical gain on crystal orientation in wurtzite–GaN strained quantum-well lasers , 1997 .

[25]  Finite element analysis of strain effects on electronic and transport properties in quantum dots and wires , 1998, cond-mat/9806029.

[26]  F. Ponce,et al.  Observation of coreless dislocations in α-GaN , 1997 .

[27]  Lester F. Eastman,et al.  Scattering of electrons at threading dislocations in GaN , 1998 .

[28]  Jerry R. Meyer,et al.  Band parameters for III–V compound semiconductors and their alloys , 2001 .

[29]  H. Amano,et al.  GaN/GaInN/GaN Double Heterostructure Light Emitting Diode Fabricated Using Plasma-Assisted Molecular Beam Epitaxy , 1995 .

[30]  Masao Ikeda,et al.  Characterization of threading dislocations in GaN epitaxial layers , 2000 .

[31]  Y. Segawa,et al.  Influence of threading dislocations on the near-bandedge photoluminescence of wurtzite GaN thin films on SiC substrate , 2000 .

[32]  B. Goldberg,et al.  Simulation evidence for lateral excitation transfer in a self-assembled quantum-dot array , 2003 .