An empirical potential approach to structural stability of GaNxAs1−x thin films on GaAs(111)

2005 ◽  
Vol 244 (1-4) ◽  
pp. 170-173 ◽  
Author(s):  
Tomonori Ito ◽  
Takashi Suda ◽  
Toru Akiyama ◽  
Kohji Nakamura
Keyword(s):  
Thin Films ◽  
Structural Stability ◽  
Potential Approach ◽  
Empirical Potential

An empirical potential approach to dislocation formation and structural stability in GaNxAs1−x

2005 ◽  
Vol 244 (1-4) ◽  
pp. 182-185 ◽  
Author(s):  
Keiichi Kawamoto ◽  
Takashi Suda ◽  
Toru Akiyama ◽  
Kohji Nakamura ◽  
Tomonori Ito
Keyword(s):  
Structural Stability ◽  
Potential Approach ◽  
Empirical Potential ◽  
Dislocation Formation

An empirical potential approach to structural stability of GaNxAs1−x

2003 ◽  
Vol 258 (3-4) ◽  
pp. 277-282 ◽  
Author(s):  
Takashi Suda ◽  
Yoshihiro Kangawa ◽  
Kohji Nakamura ◽  
Tomonori Ito
Keyword(s):  
Structural Stability ◽  
Potential Approach ◽  
Empirical Potential

An empirical potential approach to the structural stability of InAs stacking-fault tetrahedron in InAs/GaAs(111)

2007 ◽  
Vol 301-302 ◽  
pp. 837-840 ◽  
Author(s):  
Hidenori Joe ◽  
Toru Akiyama ◽  
Kohji Nakamura ◽  
Kiyoshi Kanisawa ◽  
Tomonori Ito
Keyword(s):  
Structural Stability ◽  
Stacking Fault ◽  
Potential Approach ◽  
Empirical Potential ◽  
Stacking Fault Tetrahedron

Empirical potential approach to the epitaxial relationship between AlN thin films and Si(001) substrates

2011 ◽  
Vol 8 (5) ◽  
pp. 1569-1572
Author(s):  
Tomonori Ito ◽  
Haruo Nakano ◽  
Toru Akiyama ◽  
Kohji Nakamura
Keyword(s):  
Thin Films ◽  
Epitaxial Relationship ◽  
Potential Approach ◽  
Empirical Potential

Structural stability of titania thin films

1999 ◽  
Vol 11 (8) ◽  
pp. 1231-1237 ◽  
Author(s):  
P.I Gouma ◽  
P.K Dutta ◽  
M.J Mills
Keyword(s):  
Thin Films ◽  
Structural Stability

scholarly journals Structural Stability of Magnetic Tunnel Junction Based Molecular Spintronics Devices (MTJMSD)

2020 ◽  
Author(s):  
Joshua Dillard ◽  
Uzma Amir ◽  
Pawan Tyagi ◽  
Vincent Lamberti
Keyword(s):  
Thin Films ◽  
Structural Stability ◽  
Tunnel Junction ◽  
Magnetic Tunnel Junction ◽  
Thin Film Deposition ◽  
Film Deposition ◽  
Molecular Devices ◽  
Metal Electrodes ◽  
Molecular Spintronics ◽  
Ferromagnetic Electrodes

Abstract Harnessing the exotic properties of molecular level nanostructures to produce novel sensors, metamaterials, and futuristic computer devices can be technologically transformative. In addition, connecting the molecular nanostructures to ferromagnetic electrodes bring the unprecedented opportunity of making spin property based molecular devices. We have demonstrated that magnetic tunnel junction based molecular spintronics device (MTJMSD) approach to address numerous technological hurdles that have been inhibiting this field for decades (P. Tyagi, J. Mater. Chem., Vol. 21, 4733). MTJMSD approach is based on producing a capacitor like a testbed where two metal electrodes are separated by an ultrathin insulator and subsequently bridging the molecule nanostructure across the insulator to transform a capacitor into a molecular device. Our prior work showed that MTJMSDs produced extremely intriguing phenomenon such as room temperature current suppression by six orders, spin photovoltaic effect, and evolution of new forms of magnetic metamaterials arising due to the interaction of the magnetic a molecule with two ferromagnetic thin films. However, making robust and reproducible electrical connections with exotic molecules with ferromagnetic electrodes is full of challenges and requires attention to MTJMSD structural stability. This paper focuses on MTJMSD stability by describing the overall fabrication protocol and the associated potential threat to reliability. MTJMSD is based on microfabrication methods such as (a) photolithography for patterning the ferromagnetic electrodes, (b) sputtering of metallic thin films and insulator, and (c) at the end electrochemical process for bridging the molecules between two ferromagnetic films separated by ∼ 2nm insulating gap. For the successful MTJMSD fabrication, the selection of ferromagnetic metal electrodes and thickness was found to be a deterministic factor in designing the photolithography, thin film deposition strategy, and molecular bridging process. We mainly used isotropic NiFe soft magnetic material and anisotropic Cobalt (Co) with significant magnetic hardness. We found Co was susceptible to chemical etching when directly exposed to photoresist developer and aged molecular solution. However, NiFe was very stable against the chemicals we used in the MTJMSD fabrication. As compared to NiFe, the Co films with > 10nm thickness were susceptible to mechanical stress-induced nanoscale deformities. However, cobalt was essential to produce (a) low leakage current before transforming the capacitor from the magnetic tunnel junction into molecular devices and (b) tailoring the magnetic properties of the ferromagnetic electrodes. This paper describes our overall MTJMSD fabrication scheme and process optimization to overcome various challenges to produce stable and reliable MTJMSDs. We also discuss the role of mechanical stresses arising during the sputtering of the ultrathin insulator and how to overcome that challenge by optimizing the insulator growth process. This paper will benefit researchers striving to make nanoscale spintronics devices for solving grand challenges in developing advanced sensors, magnetic metamaterials, and computer devices.

Sign in / Sign up

Export Citation Format

Share Document