scholarly journals Critical Layer Thickness for Columnar Growth Nanostructures of CoPt-based Alloy-Oxide Granular Media used for Perpendicular Magnetic Recording

2017 ◽  
Vol 60 (3) ◽  
pp. 112-118 ◽  
Author(s):  
Shingo SASAKI ◽  
Yuzo SASAKI ◽  
Shin SAITO
Keyword(s):  
Layer Thickness ◽  
Magnetic Recording ◽  
Granular Media ◽  
Critical Layer ◽  
Critical Layer Thickness ◽  
Columnar Growth ◽  
Perpendicular Magnetic Recording

Coupled Granular/Continuous Media – Results and Challenges

MRS Advances ◽  
2017 ◽  
Vol 2 (49) ◽  
pp. 2661-2668
Author(s):  
Horia Gavrila ◽  
Doina Elena Gavrila
Keyword(s):  
Thermal Stability ◽  
Grain Size ◽  
Magnetic Recording ◽  
Granular Media ◽  
Signal To Noise Ratio ◽  
Signal To Noise ◽  
Theoretical Limit ◽  
Perpendicular Recording ◽  
Perpendicular Magnetic Recording ◽  
Longitudinal Recording

ABSTRACTWhile the most promising longitudinal recording systems cannot surpass the theoretical limit of about 200 Gb/in2 for areal recording density and the demand for higher densities is permanently increasing, the perpendicular magnetic recording constitutes the realistic issue to the longitudinal one. The perpendicular magnetic recording offers significant advantages, the most important being stronger write and read fields, and therefore the use of media of higher anisotropy, smaller grain size, higher signal-to-noise ratio, and a better thermal stability. Unfortunately, the perpendicular recording has to cope some important physical and technological difficulties. To overcome them, many ingenious solutions were proposed. In this paper the coupled granular/continuous (CGC) media, a subtle association of the continuous and, respectively, granular media, are analysed from the viewpoint of their magnetic and recording properties. The challenges and possible improvements of CGC media are discussed.

Modulation Structure and Superhardness Effect of VC/TiN Nano-Multilayer Films

2012 ◽  
Vol 184-185 ◽  
pp. 1080-1083
Author(s):  
Jian Ling Yue ◽  
Wei Shi ◽  
Ge Yang Li
Keyword(s):  
Elastic Modulus ◽  
Magnetron Sputtering ◽  
Layer Thickness ◽  
Coherent Structure ◽  
Multilayer Films ◽  
Critical Layer ◽  
Maximum Hardness ◽  
Critical Layer Thickness ◽  
The Relationship

A series of VC/TiN nano-multilayer films with various TiN layer thicknesses were synthesized by magnetron sputtering method. The relationship between the modulation structure and superhardness effect of the multilayer films were investigated. The results reveal that TiN below a critical layer thickness grows coherently with VC layers in multilayers. Correspondingly, the hardness and elastic modulus of the multilayers increase significantly. The maximum hardness and modulus achieved in these multilayers is 40.7GPa and 328GPa.With further increase in the TiN layer thickness, coherent structure of multilayers are destroyed, resulting in a remarkable decrease of hardness and modulus. The superhardness effect of multilayers is related to the three directional strains generated from the coherent structure.

Indium incorporation efficiency and critical layer thickness of (202¯1) InGaN layers on GaN

2012 ◽  
Vol 101 (20) ◽  
pp. 202102 ◽  
Author(s):  
Simon Ploch ◽  
Tim Wernicke ◽  
Martin Frentrup ◽  
Markus Pristovsek ◽  
Markus Weyers ◽  
...  
Keyword(s):  
Layer Thickness ◽  
Critical Layer ◽  
Critical Layer Thickness ◽  
Incorporation Efficiency

Critical Layer Thickness: Theory and Experiment in the ZnSe/GaAs (001) Material System

2017 ◽  
Vol 26 (03) ◽  
pp. 1740020
Author(s):  
Tedi Kujofsa ◽  
John E. Ayers
Keyword(s):  
Layer Thickness ◽  
Flow Model ◽  
Driving Forces ◽  
Lattice Relaxation ◽  
Theoretical Models ◽  
Critical Layer ◽  
Material System ◽  
Critical Layer Thickness ◽  
Experimental Resolution ◽  
Experimental Strain

The critical layer thickness (CLT) determines the criteria for dislocation formation and the onset of lattice relaxation. Although several theoretical models have been developed for the critical layer thickness, experimentally-measured CLTs in ZnSe/GaAs (001) heterostructures are often at variance with one another as well as with established theories. In a previous work [T. Kujofsa et al., J. Vac. Sci. Technol. B, 34, 051201 (2016)], we showed that the experimentally measured CLT may be much larger than the equilibrium value when using finite experimental resolution. In this work, we apply a general dislocation flow model to determine the apparent critical layer thickness as a function of the experimental resolution for ZnSe/GaAs (001) heterostructures. More importantly, we compare the results utilizing different equilibrium theories and therefore varying driving forces for the lattice relaxation in order to determine which established models are consistent with several measured values of CLT for ZnSe/GaAs (001) once kinetically-limited relaxation and finite experimental strain resolution are taken into account.

Sign in / Sign up

Export Citation Format

Share Document