English
Related papers

Related papers: Strain relaxation in GaN grown on vicinal 4H-SiC(0…

200 papers

Strain relaxation of thick InGaN layers was studied in order to develop technology of InGaN templates for deposition of InGaN Quantum Wells (QWs) and InGaN layers of high-In-content. In this paper, we show that InGaN layers grown on…

(a+c) dislocations in hexagonal materials are typically observed to be dissociated into partial dislocations. Edge (a+c) dislocations are introduced into (0001) nitride semiconductor layers by the process of plastic relaxation. As there is…

Applied Physics · Physics 2023-10-19 J. Smalc-Koziorowska , J. Moneta , G. Muziol , W. Chrominski , R. Kernke , M. Albrecht , T. Schulz , I. Belabbas

Top-down fabricated GaN nanowires, 250 nm in diameter and with various heights, have been used to experimentally determine the evolution of strain along the vertical direction of 1-dimensional objects. X-ray diffraction and…

Coalescence overgrowth of pattern-grown GaN nanocolumns (NC) on c-plane sapphire substrate with metal organic chemical vapour deposition is demonstrated. The subsequent coalescence overgrowth opens a possibility for dislocation reduction…

Mesoscale and Nanoscale Physics · Physics 2010-01-13 Hsiang-Chen Wang , Chun-Ming Yeh , Tsung-Yi Tang , C. C. Yang , T. Malinauskas , K. Jarasiunas

Two types of nucleation layers (NLs), including in-situ low-temperature grown GaN (LT-GaN) and ex-situ sputtered physical vapor deposition AlN (PVD-AlN), are applied on cone-shaped nanoscale patterned sapphire substrate (NPSS). The initial…

The strain state and composition of a 400 nm thick (In,Ga)N layer grown by metal-organic chemical vapor deposition on a GaN template are investigated by spatially integrated x-ray diffraction and cathodoluminescence (CL) spectroscopy as…

Materials Science · Physics 2013-02-06 Benjamin Wilsch , Uwe Jahn , Bernd Jenichen , Jonas Lähnemann , Holger T. Grahn

Ammonia (NH3) is commonly used as group V precursor in gallium nitride (GaN) metalorganic chemical vapor deposition (MOCVD). The high background carbon (C) impurity in MOCVD GaN is related to the low pyrolysis efficiency of NH3, which…

Applied Physics · Physics 2021-07-07 Yuxuan Zhang , Zhaoying Chen , Kaitian Zhang , Zixuan Feng , Hongping Zhao

We report on structural and optical properties of InGaN/GaN thin films, with a 0.46o misalignment between the surface and the (0001) plane, which were grown by metal-organic chemical vapor deposition (MOCVD) on 0.34o miscut sapphire…

Materials Science · Physics 2019-02-19 I. A. Ajia , S. M. C. Miranda , N. Franco , E. Alves , K. Lorenz , K. P. O'Donnell , I. S. Roqan

The coalescence in dense arrays of spontaneously formed GaN nanowires proceeds by bundling: adjacent nanowires bend and merge at their top, thus reducing their surface energy at the expense of the elastic energy of bending. We give a…

Materials Science · Physics 2017-01-03 Vladimir M. Kaganer , Bernd Jenichen , Oliver Brandt

Selective area growth of GaN nanostructures has been performed on full 2" c-sapphire substrates using Si3N4 mask patterned by nanoimprint lithography (array of 400 nm diameter circular holes). A new process has been developed to improve the…

Heteroepitaxy conventionally relies on rigid crystalline substrates, implicitly assuming that lattice and thermal mismatch must be accommodated within the epitaxial layer, leading to residual strain and defects that worsen with increasing…

The evolution of surface morphology during the growth of N-polar (000-1) GaN under N-rich condition is studied by kinetic Monte Carlo (kMC) simulations for two substrates miscuts 2deg and 4deg. The results are compared with experimentally…

We report on the impact of growth conditions on surface hillock density of N-polar GaN grown on nominally on-axis (0001) sapphire substrate by metal organic chemical vapor deposition (MOCVD). Large reduction in hillock density was achieved…

Materials Science · Physics 2017-05-12 Jonathan Marini , Jeffrey Leathersich , Isra Mahaboob , John Bulmer , Neil Newman , F. , Shahedipour-Sandvik

Cracking of thick GaN films on sapphire substrates during the cooling down after the growth was studied. The cracking was suppressed by increasing the film-to-substrate thickness ratio and by using an intermediate carbon buffer layer, that…

Materials Science · Physics 2019-03-06 Vladislav Voronenkov , Andrey Leonidov , Yuri Lelikov , Andrey Zubrilov , Yuri Shreter

The use of highly efficient and solarblind GaN photocathodes as part of multichannel plate UV detectors for applications in astronomy would strongly benefit from the direct growth of GaN on typical window materials with high transmission…

The mechanical stability of commercial GaP/Si templates during thermal an-nealing and subsequent MOCVD growth of GaP and AlGaP is investigated.Although the GaP layer of the template originally presents an excellent surfacemorphology,…

Thin InN and GaN/InN films were grown on oxygen-polar (O) (000-1) and zinc-polar (Zn) (0001) zinc oxide (ZnO) by plasma-assisted molecular beam epitaxy (PAMBE). The influence of the growth rate (GR) and the substrate polarity on the growth…

Materials Science · Physics 2018-10-17 Torsten Ernst , Caroline Chèze , Raffaella Calarco

GaN-nanorods grown on Si(111) substrates are found strain- and defect-free as characterized by micro Raman spectroscopy, secondary electron (SE) and cathode-luminescence (CL) imaging. The matrix supporting the nanorods bears the brunt of…

Materials Science · Physics 2007-05-23 H. W. Seo , Q. Y. Chen , M. N. Iliev , W. K. Chu , L. W. Tu , C. L. Hsiao , James K. Meen

We investigate the strain state of ensembles of thin and nearly coalescence-free self-assembled GaN nanowires prepared by plasma-assisted molecular beam epitaxy on Ti/Al$_{2}$O$_{3}(0001)$ substrates. The shifts of Bragg peaks in…

AlScN thin films were grown via metalorganic chemical vapor deposition (MOCVD), showing controllable incorporation of scandium (Sc) into the AlN lattices. Systematic variation of growth parameters demonstrated an obvious influence on Sc…

‹ Prev 1 2 3 10 Next ›