Determination of the cubic to hexagonal fraction in GaN nucleation layers using grazing incidence x-ray scattering

1998 ◽  
Vol 72 (23) ◽  
pp. 2972-2974 ◽  
Author(s):  
A. Munkholm ◽  
C. Thompson ◽  
C. M. Foster ◽  
J. A. Eastman ◽  
O. Auciello ◽  
...  
1991 ◽  
Vol 239 ◽  
Author(s):  
Ramnath Venkatraman ◽  
Paul R. Besser ◽  
Sean Brennan ◽  
John C. Bravman

ABSTRACTWe have measured elastic strain distributions with depth as a function of temperature in Al thin films of various thicknesses on oxidized silicon using synchrotron grazing incidence X-ray scattering (GIXS). Disregarding minor surface relaxation effects that depend on the film thickness, it is shown that there are no gross strain gradients in these films in the range of temperatures (between room temperature and 400°C) considered. We also observe X-ray line broadening effects, suggesting an accumulation of dislocations on cooling the films, and their annealing out as the films are reheated.


1996 ◽  
Vol 437 ◽  
Author(s):  
P. Guenard ◽  
G. Renaud ◽  
A. Barbier ◽  
M. Gautier-Soyer

AbstractWe have investigated the unreconstructed (0001) surface structure of sapphire (α-Al2O3) by Grazing Incidence X-ray Scattering. Modulations along the crystal truncation rods were analyzed in order to determine the chemical nature of the terminating plane, and the structural relaxations of the first few atomic planes below the surface. The most likely model yields a single Al layer termination with relaxations of the first four planes of -51%, +16%, -29% and +20% respectively. These results compare well with the most recent theoretical calculations on this surface.


1998 ◽  
Vol 05 (01) ◽  
pp. 321-324 ◽  
Author(s):  
P. Guénard ◽  
G. Renaud ◽  
A. Barbier ◽  
M. Gautier-Soyer

We have investigated the unreconstructed (0001) surface structure of sapphire (α- Al 2 O 3) by grazing incidence X-ray scattering. Modulations along the crystal truncation rods were analyzed in order to determine the chemical nature of the terminating plane, and the structural relaxations of the first few atomic planes below the surfoce. The most likely model yields a single Al layer termination with relaxations of the first four planes of -51%, +16%, -29% and +20% respectively. These results compare well with the most recent theoretical calculations on this surface.


1999 ◽  
Vol 602 ◽  
Author(s):  
M. Petit ◽  
L. J. Martinez-Miranda ◽  
M. Rajeswari ◽  
A. Biswas ◽  
D. J. Kang ◽  
...  

AbstractWe have performed depth profile analyses of the lattice parameters in epitaxial thin films of La1−xCaxMno3 (LCMO), where x = 0.33 or 0.3, to understand the evolution of strain relaxation processes in these materials. The analyses were done using Grazing Incidence X-ray Scattering (GIXS) on films of different thicnesses on two different substrates, (100) oriented LaAlO3 (LAO), with a lattice mismatch of ∼2% and (110) oriented NGO, with a lattice mismatch of less than 0.1%. Films grown on LAO can exhibit up to three in-plane strained lattice constants, corresponding to a slight orthorhombic distortion of the crystal, as well as near-surface and columnar lattice relaxation. As a function of film thickness, a crossover from a strained film to a mixture of strained and relaxed regions in the film occurs in the range of 700 Å. The structural evolution at this thickness coincides with a change in the resistivity curve near the metalinsulator transition. The in-plane compressive strain has a range of 0.2 – 1.5%, depending on the film thickness for filsm in the range of 400 - 1500 A.


2014 ◽  
Vol 115 (20) ◽  
pp. 204311 ◽  
Author(s):  
Nie Zhao ◽  
Chunming Yang ◽  
Qian Zhang ◽  
Xueming Lu ◽  
Yuzhu Wang ◽  
...  

1999 ◽  
Vol 86 (12) ◽  
pp. 6763-6769 ◽  
Author(s):  
Markus Rauscher ◽  
Rogerio Paniago ◽  
Hartmut Metzger ◽  
Zoltan Kovats ◽  
Jan Domke ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document