Defect ordering in epitaxial a-GaN(QQ01)

Self-assembled Multilayers of Silica Nanospheres for Defect Reduction in Non- and Semipolar Gallium Nitride Epitaxial Layers

Non- and semipolar GaN have great potential to improve the efficiency of light emitting devices due to much reduced internal electric fields. However, heteroepitaxial GaN growth in these crystal orientations suffers from very high dislocation and stacking faults densities. Here, we report a facile method to obtain low defect density non- and semipolar heteroepitaxial GaN via selective area epit...

Reconstruction control of magnetic properties during epitaxial growth of ferromagnetic Mn3-deltaGa on Wurtzite GaN(0001).

Binary ferromagnetic Mn(3-delta)Ga (1.2<3-delta< or =1.5) crystalline thin films have been epitaxially grown on wurtzite GaN(0001) surfaces using rf N-plasma molecular beam epitaxy. The film structure is face-centered tetragonal with CuAu type-I (L1(0)) ordering with (111) orientation. The in-plane epitaxial relationship to GaN is nearly ideal with [110](MnGa) parallel[1100](GaN) and [112](MnGa...

Reduction of dislocation density in epitaxial GaN layers by overgrowth of defect-related etch pits

Cathodoluminescence and Transmission Electron Microscopy Study of the Influence of Crystal Defects on Optical Transitions in GaN

Defect related states and excitonic transitions in epitaxial GaN have been studied by combining cathodoluminescence and transmission electron microscopy. A series of deep levels with energies at about 2.4, 2.6 and 2.8 eV has been found by low temperature cathodoluminescence on freestanding 150 mm thick epitaxial GaN. These deep levels are characterised by a high recombination efficiency. They a...

Transmission electron microscopy study of defect reduction in two-step lateral epitaxial overgrown nonplanar GaN substrate templates

Transmission electron microscopy (TEM) is carried out to characterize the extended defect reduction in low-defect nonplanar GaN substrate templates grown by lateral epitaxial overgrowth (LEO). The LEO nonplanar GaN substrate template has a trapezoidal cross section with smooth (0 0 0 1) and f1 1 2̄ 2g facets. We demonstrate here the dislocation distribution and behavior in both ordinary LEO and ...