Study of stacking fault effect on magnetic anisotropy of CoPtCr–SiO2 perpendicular media by synchrotron radiation x-ray diffraction

2006 ◽  
Vol 99 (8) ◽  
pp. 08G911 ◽  
Author(s):  
T. Kubo ◽  
Y. Kuboki ◽  
R. Tanuma ◽  
A. Saito ◽  
S. Watanabe ◽  
...  
2021 ◽  
pp. 1-7
Author(s):  
Brian K. Tanner ◽  
Patrick J. McNally ◽  
Andreas N. Danilewsky

X-ray diffraction imaging (XRDI) (topography) measurements of silicon die warpage within fully packaged commercial quad-flat no-lead devices are described. Using synchrotron radiation, it has been shown that the tilt of the lattice planes in the Analog Devices AD9253 die initially falls, but after 100 °C, it rises again. The twist across the die wafer falls linearly with an increase in temperature. At 200 °C, the tilt varies approximately linearly with position, that is, displacement varies quadratically along the die. The warpage is approximately reversible on cooling, suggesting that it has a simple paraboloidal form prior to encapsulation; the complex tilt and twisting result from the polymer setting process. Feasibility studies are reported, which demonstrate that a divergent beam and quasi-monochromatic radiation from a sealed X-ray tube can be used to perform warpage measurements by XRDI in the laboratory. Existing tools have limitations because of the geometry of the X-ray optics, resulting in applicability only to simple warpage structures. The necessary modifications required for use in situations of complex warpage, for example, in multiple die interconnected packages are specified.


2020 ◽  
Vol 117 (25) ◽  
pp. 252905
Author(s):  
Tomohiro Abe ◽  
Sangwook Kim ◽  
Chikako Moriyoshi ◽  
Yuuki Kitanaka ◽  
Yuji Noguchi ◽  
...  

2017 ◽  
Vol 81 (4) ◽  
pp. 917-922
Author(s):  
Peter Elliott

AbstractThe crystal structure of the copper aluminium phosphate mineral sieleckiite, Cu3Al4(PO4)2 (OH)12·2H2O, from the Mt Oxide copper mine, Queensland, Australia was solved from single-crystal X-ray diffraction data utilizing synchrotron radiation. Sieleckiite has monoclinic rather than triclinic symmetry as previously reported and is space group C2/m with unit-cell parameters a = 11.711(2), b = 6.9233(14), c = 9.828(2) Å, β = 92.88(3)°, V = 795.8(3) Å3and Z = 2. The crystal structure, which has been refined to R1 = 0.0456 on the basis of 1186 unique reflections with Fo > 4σF, is a framework of corner-, edge- and face- sharing Cu and Al octahedra and PO4 tetrahedra.


1999 ◽  
Vol 562 ◽  
Author(s):  
K. Attenborough ◽  
M. Cerisier ◽  
H. Boeve ◽  
J. De Boeck ◽  
G. Borghs ◽  
...  

ABSTRACTWe have studied the magnetic and structural properties of thin electrodeposited Co and Cu layers grown directly onto (100) n-GaAs and have investigated the influence of a buffer layer. A dominant fourfold anisotropy with a uniaxial contribution is observed in 10 nm Co electrodeposited films on GaAs. An easy axis is observed in the [001] GaAs direction with two hard axes of differing coercivities parallel to the [011] and [011] directions. For thicker films the easy axes in the [001] direction becomes less pronounced and the fourfold anisotropy becomes less dominant. Co films of similar thicknesses deposited onto an electrodeposited Cu buffer layer were nearly isotropic. From X-ray diffraction 21 nm Co layers on GaAs were found to be hcp with the c-axis tending to be in the plane of the film. The anisotropy is ascribed to the Co/GaAs interface and is held responsible for the unique spin-valve properties seen recently in electrodeposited Co/Cu films.


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