Thermally induced strain relaxation in SiGe/Si heterostructures with low-temperature buffer layers

2005 ◽  
Vol 2 (6) ◽  
pp. 1938-1942 ◽  
Author(s):  
V. I. Vdovin ◽  
T. G. Yugova ◽  
M. M. Rzaev ◽  
F. Schäffler ◽  
M.G. Mil'vidskii
Keyword(s):  
Low Temperature ◽  
Strain Relaxation ◽  
Buffer Layers ◽  
Thermally Induced

Effects of thermal processing on (SimGen)p superlattices

1991 ◽  
Vol 69 (3-4) ◽  
pp. 241-245 ◽  
Author(s):  
R. Pascual ◽  
S. Saimoto ◽  
J. M. Baribeau
Keyword(s):  
Structural Changes ◽  
Strain Relaxation ◽  
Buffer Layers ◽  
X Ray Diffraction ◽  
Thermally Induced ◽  
Exponential Decay Rate ◽  
Superlattice Peak ◽  
Short Period ◽  
Short Period Superlattices ◽  
Short Annealing

In this work we report an X-ray diffraction study of thermally induced interdiffusion and strain relaxation in molecular beam epitaxy grown (SimGen)p short-period superlattices. Both rapid and furnace thermal annealings in the range 500–700 °C were used to generate structural changes in the various samples. Strain relaxation was studied by measuring the shift of (400) superlattice peaks on annealing. About half of the strain was relieved in the first few minutes of annealing. The remaining strain was relieved at a much lower rate and residual strain persisted even after several hours of heating. Also, the decay of the first order (000) superlattice peak was monitored as a function of annealing time. An initial rapid nonexponential decrease in peak intensity was observed, coincident with the sudden strain relaxation found at short annealing times. A slower, exponential decay rate was observed at longer times, so that a wavelength-dependent interdiffusion coefficient Dλ could be calculated. The variation of Dλ with the superlattice period and the effect of different substrates and buffer layers was studied. Diffusion was faster in structures alternating thin Si and thick Ge layers suggesting that migration of Si into Ge is the dominant diffusion process.

Transformation behavior of yttria stabilized tetragonal zirconia polycrystal–TiB2 composites

2001 ◽  
Vol 16 (7) ◽  
pp. 2158-2169 ◽  
Author(s):  
B. Basu ◽  
J. Vleugels ◽  
O. Van Der Biest
Keyword(s):  
Thermal Expansion ◽  
Phase Transformation ◽  
Low Temperature ◽  
Tetragonal Zirconia ◽  
Mechanical Analysis ◽  
Transformation Behavior ◽  
Thermal Expansion Data ◽  
Thermally Induced ◽  
First Time ◽  
Tetragonal Zirconia Polycrystal

The objective of the present article is to study the influence of TiB2 addition on the transformation behavior of yttria stabilized tetragonal zirconia polycrystals (Y-TZP). A range of TZP(Y)–TiB2 composites with different zirconia starting powder grades and TiB2 phase contents (up to 50 vol%) were processed by the hot-pressing route. Thermal expansion data, as obtained by thermo-mechanical analysis were used to assess the ZrO2 phase transformation in the composites. The thermal expansion hysteresis of the transformable ceramics provides information concerning the transformation behavior in the temperature range of the martensitic transformation and the low-temperature degradation. Furthermore, the transformation behavior and susceptibility to low-temperature degradation during thermal cycling were characterized in terms of the overall amount and distribution of the yttria stabilizer, zirconia grain size, possible dissolution of TiB2 phase, and the amount of residual stress generated in the Y-TZP matrix due to the addition of titanium diboride particles. For the first time, it is demonstrated in the present work that the thermally induced phase transformation of tetragonal zirconia in the Y-TZP composites can be controlled by the intentional addition of the monoclinic zirconia particles into the 3Y-TZP matrix.

Thermally Induced Symmetry and Disorder: The Low-Temperature Crystal Structure of Diaquadichlorodimethyltin · 15-crown-5

1996 ◽  
Vol 1 (3) ◽  
pp. 359-363 ◽  
Author(s):  
Glenn P. A. Yap ◽  
Mostafa M. Amini ◽  
Seik W. Ng ◽  
Anne E. Counterman ◽  
Arnold L. Rheingold
Keyword(s):  
Crystal Structure ◽  
Low Temperature ◽  
Thermally Induced ◽  
Low Temperature Crystal Structure

Short-period (Si14 / Si0.75 Ge0.25)20 Superlattices for the Growth of High-quality Si0.75 Ge0.25

2003 ◽  
Vol 765 ◽  
Author(s):  
M.M. Rahman ◽  
T. Tambo ◽  
C. Tatsuyama
Keyword(s):  
Low Temperature ◽  
Alloy Layer ◽  
Buffer Layers ◽  
Threading Dislocations ◽  
Strained Layers ◽  
Temperature Growth ◽  
Low Temperature Growth ◽  
Defect Sites ◽  
Short Period ◽  
Different Temperatures

AbstractIn the present experiment, we have grown 2500-Å thick Si0.75Ge0.25 alloy layers on Si(001) substrate by MBE process using a short-period (Si14/Si0.75Ge0.25)20 superlattice (SL) as buffer layers. In the SL layers, first a layer of 14 monolayers (MLs) of Si (thickness about 20Å) then a thin layer of Si0.75Ge0.25 (thickness 5-6Å) were grown. This Si/(Si0.75Ge0.25) bilayers were repeated for 20 times. The buffer layers were grown at different temperatures from 300-400°C and the alloy layers were then grown at 500°C on the buffer layers. The alloy layer showed low residual strain (about -0.16%) and smooth surface (rms roughness ~15Å) with 300°C grown SL buffer. Low temperature growth of Si in SL layer introduces point defects and low temperature growth of Si1-xGex in SL layer reduces the Ge segregation length, which leads to strained SL layer formation. Strained layers are capable to make barrier for the propagation of threading dislocations and point defect sites can trap the dislocations.

A Thermally Induced Low-temperature Intramolecular Redox Reaction of bis(pyridine)silver(I) Permanganate and its hemipyridine Solvate

2006 ◽  
Vol 31 (1) ◽  
pp. 30-34 ◽  
Author(s):  
László Kótai ◽  
Judit Fodor ◽  
Emma Jakab ◽  
István Sajó ◽  
Piroska Szabó ◽  
...  
Keyword(s):  
Low Temperature ◽  
Redox Reaction ◽  
Thermally Induced
Sign in / Sign up

Export Citation Format

Share Document