Aromaticity-Controlled Thermal Stability of Photochromic Systems Based on a Six-Membered Ring as Ethene Bridges: Photochemical and Kinetic Studies

2012 ◽  
Vol 18 (37) ◽  
pp. 11685-11694 ◽  
Author(s):  
Yuheng Yang ◽  
Yongshu Xie ◽  
Qiong Zhang ◽  
Keitaro Nakatani ◽  
He Tian ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Kinetic Studies ◽  
Membered Ring ◽  
Thermal Stability Of

Propargylic-Terminated Prepolymers. 5. Mechanistic and Kinetic Studies of the Polymerization Reaction of Compounds with an Imide Group meta to the Propargylic Function

1996 ◽  
Vol 8 (4) ◽  
pp. 555-578 ◽  
Author(s):  
Marie–Florence Grenier–Loustalot ◽  
Corinne Sanglar
Keyword(s):  
Thermal Stability ◽  
Reaction Kinetics ◽  
Liquid State ◽  
Reaction Path ◽  
Kinetic Studies ◽  
Polymerization Reaction ◽  
Imide Group ◽  
Final System ◽  
Thermal Stability Of

We have synthesized two functionalized prepolymers with an imide group meta to the propargylic function in their central skeleton. Based on data obtained by a variety of solid and liquid state physicochemical techniques, we show that meta substitution modifies the reaction path and leads to the formation of two chromenes, α and β. In addition, the reaction kinetics and thermal stability of the final system are affected by the presence of an imide group in the structure of the propargylic prepolymer.

Silicides for 65 nm CMOS and Beyond

2003 ◽  
Vol 765 ◽  
Author(s):  
Jorge A. Kittl ◽  
Anne Lauwers ◽  
Oxana Chamirian ◽  
Mark Van Dal ◽  
Amal Akheyar ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Sheet Resistance ◽  
Kinetic Studies ◽  
Process Window ◽  
Thermal Budget ◽  
Diffusion Limited ◽  
Mechanism Of Degradation ◽  
Low Thermal Budget ◽  
Thermal Stability Of ◽  
Ni Silicides

AbstractAn overview of silicide development for the 65 nm node and beyond is presented. The scaling behavior of Co based and Ni based silicides to sub-100 nm junctions and sub-40 nm gate lengths was investigated. Co and Co-Ni silicides required a high thermal budget to achieve low diode leakage. Even for lower thermal budgets, the sheet resistance of Co and Co-Ni silicides increased at gate lengths below 40 nm. NiSi had low sheet resistance down to 30 nm gate lengths exhibiting a reverse linewidth effect (sheet resistance decreased with decreasing linewidth), achieved lower contact resistivity than CoSi2 and lower diode leakage for similar sheet resistance values. Bridging issues cannot be ignored for NiSi, in particular for thicker Ni films, higher RTP temperatures and in the presence of Ti. Material issues for the application of NiSi were also investigated. Ni2Si was found to grow with diffusion limited kinetics in the 225-300°C range, with an activation energy of 1.5 eV. Results of the kinetic studies were used to design a two-step RTP process that limited the silicide thickness on small features by a low thermal budget first RTP step, reducing the reverse linewidth effect and avoiding excessive silicidation. In the presence of an interfacial oxide, undesired epitaxial NiSi2 pyramidal grains grew directly at temperatures as low as 310°C on p+ Si. Thermal stability of NiSi was also investigated. We found that the initial mechanism of degradation for thin NiSi films was agglomeration, with activation energies of 2.5-3 eV. The surface after agglomeration remained quite flat with alternating NiSi and exposed Si areas, while the interface roughened significantly. Thick films also degraded initially by agglomeration at low temperatures, but by transformation to NiSi2 at higher temperatures. The addition of Pt improved thermal stability of NiSi films against agglomeration. The Ni/Si-Ge reaction was also studied, finding that the addition of Ge reduced the thermal process window and resulted in a slightly higher resistivity.

scholarly journals Thermal Spectroscopy and Kinetic Studies of PEO/PVDF Loaded by Carbon Nanotubes

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Laila Hussein Gaabour
Keyword(s):  
Activation Energy ◽  
Carbon Nanotubes ◽  
Thermal Stability ◽  
Heating Rate ◽  
Polyvinylidene Fluoride ◽  
Kinetic Studies ◽  
Multiwalled Carbon ◽  
Polymeric Matrices ◽  
Swcnts And Mwcnts ◽  
Thermal Stability Of

Nanocomposites of polyethylene oxide (PEO) and polyvinylidene fluoride (PVDF) without and with low content of single and multiwalled carbon nanotubes (SWCNTs-MWCNTs) were prepared and studied by thermogravimetric analysis (TGA) using different heating rate. TGA results indicate that the thermal stability of neat PEO/PVDF blend was improved with both heating rate and incorporation of carbon nanotubes (CNTs). The degradation temperature for neat blend was lower than those of the nanocomposites after adding both SWCNTs and MWCNTs. As increase of heating rate, the onset of decomposition is irregularly moved to higher temperatures. This indicates that the thermal stability of the polymeric matrices has been improved after addition of CNTs. The residual weight of the samples left increased steadily with adding of both SWCNTs and MWCNTs. Kinetic thermodynamic parameters such as activation energy, enthalpy, entropy, and Gibbs free energy are evaluated from TGA data using Coats-Redfern model. The values of all parameters irregularly decrease with increasing of heating rate due to increasing of heating rate temperature, the random scission of macromolecule chain in the polymeric matrices predominates and the activation energy has a lower value.

The Ordered Phase Formation in Ti-Al-Ga Alloys

1970 ◽  
Vol 28 ◽  
pp. 440-441
Author(s):  
Shiro Fujishiro ◽  
Harold L. Gegel
Keyword(s):  
Thermal Stability ◽  
High Temperature ◽  
Titanium Alloys ◽  
Growth Kinetics ◽  
Stoichiometric Composition ◽  
Good Potential ◽  
Alpha Titanium ◽  
Cold Rolled ◽  
Kinetics Of ◽  
Thermal Stability Of

Ordered-alpha titanium alloys having a DO19 type structure have good potential for high temperature (600°C) applications, due to the thermal stability of the ordered phase and the inherent resistance to recrystallization of these alloys. Five different Ti-Al-Ga alloys consisting of equal atomic percents of aluminum and gallium solute additions up to the stoichiometric composition, Ti3(Al, Ga), were used to study the growth kinetics of the ordered phase and the nature of its interface.The alloys were homogenized in the beta region in a vacuum of about 5×10-7 torr, furnace cooled; reheated in air to 50°C below the alpha transus for hot working. The alloys were subsequently acid cleaned, annealed in vacuo, and cold rolled to about. 050 inch prior to additional homogenization

Microstructure studies of tungsten silicide schottky contacts on Gaas

1987 ◽  
Vol 45 ◽  
pp. 328-329
Author(s):  
Yih-Cheng Shih ◽  
E. L. Wilkie
Keyword(s):  
Thermal Stability ◽  
Field Effect Transistors ◽  
Schottky Contact ◽  
Schottky Contacts ◽  
Excellent Thermal Stability ◽  
Barrier Heights ◽  
Gaas Substrates ◽  
Film Adhesion ◽  
Threshold Voltages ◽  
Thermal Stability Of

Tungsten silicides (WSix) have been successfully used as the gate materials in self-aligned GaAs metal-semiconductor-field- effect transistors (MESFET). Thermal stability of the WSix/GaAs Schottky contact is of major concern since the n+ implanted source/drain regions must be annealed at high temperatures (∼ 800°C). WSi0.6 was considered the best composition to achieve good device performance due to its low stress and excellent thermal stability of the WSix/GaAs interface. The film adhesion and the uniformity in barrier heights and ideality factors of the WSi0.6 films have been improved by depositing a thin layer of pure W as the first layer on GaAs prior to WSi0.6 deposition. Recently WSi0.1 has been used successfully as the gate material in 1x10 μm GaAs FET's on the GaAs substrates which were sputter-cleaned prior to deposition. These GaAs FET's exhibited uniform threshold voltages across a 51 mm wafer with good film adhesion after annealing at 800°C for 10 min.

Thermal stability of Al-Cu-Fe icosahedral alloys

1991 ◽  
Vol 1 (12) ◽  
pp. 1823-1836 ◽  
Author(s):  
M. Bessière ◽  
A. Quivy ◽  
S. Lefebvre ◽  
J. Devaud-Rzepski ◽  
Y. Calvayrac
Keyword(s):  
Thermal Stability ◽  
Thermal Stability Of

Practical criteria for the thermal stability of a unidimensional superconductor

1994 ◽  
Vol 4 (4) ◽  
pp. 653-657
Author(s):  
B. Bonzi ◽  
M. El Khomssi ◽  
H. Lanchon-Ducauquis
Keyword(s):  
Thermal Stability ◽  
Thermal Stability Of

Time and thermal stability of magnetic properties of amorphous Fe80TM3B17 alloys

1998 ◽  
Vol 08 (PR2) ◽  
pp. Pr2-63-Pr2-66 ◽  
Author(s):  
R. Varga ◽  
P. Vojtaník ◽  
A. Lovas
Keyword(s):  
Thermal Stability ◽  
Magnetic Properties ◽  
Thermal Stability Of

Thermal stability of organic-inorganic nanocomposites based on system of dimethacrylate-tetraethoxysilane and their kinetic features

2016 ◽  
Vol 38 (3) ◽  
pp. 211-217
Author(s):  
G.I. Khovanets’ ◽  
◽  
O.Y. Makido ◽  
V.V. Kochubey ◽  
Y.G. Medvedevskikh ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Inorganic Nanocomposites ◽  
Thermal Stability Of ◽  
Kinetic Features
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