The phonon deformation potentials (PDPs), p and q, of Si1−
x
Ge
x
with the whole range of the Ge concentration x were examined in detail in pursuit of accurate strain measurements by Raman spectroscopy. An oil-immersion Raman technique was adopted to extract the PDPs of Si1−
x
Ge
x
, in which a complex sample preparation process or a stress-introduction device is not necessary. The strain-shift coefficients b
LO and b
TO, which can be calculated using the obtained PDPs, were compared with the values in the literature, and we suggested which values were best for application to accurate strain measurements. Ab initio calculation was also performed to understand the behavior of the PDPs throughout the whole range of x in Si1−
x
Ge
x
.
The behavior of water at hydrophobic interfaces can play a significant role in determining chemical reaction outcomes and physical properties. Carbon nanotubes and aluminophosphate materials have one-dimensional hydrophobic channels, which are entirely surrounded by hydrophobic interfaces. Unique water behavior was observed in such hydrophobic channels. In this article, changes in the water affinity in one-dimensional hydrophobic channels were assessed using water vapor adsorption isotherms at 303 K and grand canonical Monte Carlo simulations. Hydrophobic behavior of water adsorbed in channels wider than 3 nm was observed for both adsorption and desorption processes, owing to the hydrophobic environment. However, water showed hydrophilic properties in both adsorption and desorption processes in channels narrower than 1 nm. In intermediate-sized channels, the hydrophobic properties of water during the adsorption process were seen to transition to hydrophilic behavior during the desorption process. Hydrophilic properties in the narrow channels for both adsorption and desorption processes are a result of the relatively strong water-channel interactions (10-15 kJ mol(-1)). In the 2-3 nm channels, the water-channel interaction energy of 4-5 kJ mol(-1) was comparable to the thermal translational energy. The cohesive water interaction was approximately 35 kJ mol(-1), which was larger than the others. Thus, the water affinity change in the 2-3 nm channels for the adsorption and desorption processes was attributed to weak water-channel interactions and strong cohesive interactions. These results are inherently important to control the properties of water in hydrophobic environments.
Si1-x
Ge
x
is one of the prospective materials for the next-generation transistors due to its high carrier mobility, especially for high Ge concentration Si1-x
Ge
x
. Inducing strain in the Si1-x
Ge
x
leads to transistor performance improvement, however it is difficult to evaluate strain induced in the channel region because the strained Si1-x
Ge
x
channel may be scaled down to nanosize and relaxed complicatedly. We adopted oil-immersion Raman spectroscopy to evaluate the stress in the Si1-x
Ge
x
nanostructure. In this technique, the anisotropic biaxial stress state in the Si1-x
Ge
x
nanostructure can be evaluated. As a result, the nanostructure size dependence of the biaxial stress states in the Si1-x
Ge
x
mesa structure on the Ge substrates was obtained, which was confirmed for the Si1-x
Ge
x
with 76, 85, 92% Ge concentrations.
Anisotropic biaxial stress states in the high-Ge concentration Si1-x
Ge
x
/Ge nanostructures were evaluated by oil-immersion Raman spectroscopy. Phonon deformation potentials (PDPs) are indispensable to convert the Raman frequency shift to stress in the Si1-x
Ge
x
. Therefore, we investigated the accurate PDPs (p and q) of the Si1-x
Ge
x
with the high Ge concentration by oil-immersion Raman spectroscopy. Using the derived PDPs, the clear uniaxial stress relaxation in the strained Si1-x
Ge
x
nanostructure was observed.
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