64 research outputs found
Strain relaxation in GaN grown on vicinal 4H-SiC(0001) substrates
The strain of GaN layers grown by Metal Organic Chemical Vapor Deposition
(MOCVD) on three vicinal 4H-SiC substrates (0, 3.4 and 8 offcut from [0001]
towards [11-20] axis) is investigated by X-ray Diffraction (XRD), Raman
Scattering and Cathodoluminescence (CL). The strain relaxation mechanisms are
analyzed for each miscut angle. At a microscopic scale, the GaN layer grown on
on-axis substrate has a slight and homogeneous tensile in-plane stress due to a
uniform distribution of threading dislocations over the whole surface. The GaN
layers grown on miscut substrates presented cracks, separating areas which have
a stronger tensile in-plane stress but a more elastic strain. The plastic
relaxation mechanisms involved in these layers are attributed to the step flow
growth on misoriented surfaces (dislocations and stacking faults) and to the
macroscopical plastic release of additional thermoelastic stress upon cooling
down (cracks)
Alpha7 nicotinic acetylcholine receptors and neural network synaptic transmission in human induced pluripotent stem cell-derived neurons
Hvordan fastlægger vi oprensningskriterier for grundvandstruende forureninger?:Overvejelser på lokal- og oplandsskala
Mutations in Danish patients with long QT syndrome and the identification of a large founder family with p.F29L in KCNH2
Dynamics of pharmacy regulation in Denmark, 1932-1994:a study of profession-state relations
Conformational Studies of Phenyl- and (1-Pyrenyl)triarylmethylcarbenium Ions:Â Semiempirical Calculations and NMR Investigations under Stable Ion Conditions
Dynamics of pharmacy regulation in Denmark, 1546-1932:a study of profession-state relations
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