Scattering of Free Carriers by Oxide Precipitates in Czochralski-Grown Silicon

1985 ◽  
Vol 46 ◽  
Author(s):  
K. Nauka ◽  
W. Walukiewicz ◽  
J. Lagowski ◽  
H.C. Gatos
Keyword(s):  
Heat Treatment ◽  
Temperature Dependence ◽  
Characteristic Temperature ◽  
Scattering Mechanism ◽  
Electron Hole ◽  
Czochralski Silicon ◽  
Free Carriers ◽  
Characteristic Temperature Dependence

AbstractAnnealing of oxygen-rich Czochralski silicon at temperatures between 700°C and 1000°C introduces a new scattering mechanism which correlates very well with the presence of oxide precipitates. In lightly doped crystals (n,p ∼1015cm−3) this mechanism becomes dominant at T<170°C, and it determines to a large extent the value of the electron (hole) mobilities. The effect vanishes upon annealing at 1300°C; such heat treatment causes the dissolution of oxide precipitates. The new component mobility related to precipitates was found to exhibit a characteristic temperature dependence μ ∝ T0.5. This dependence was explained in terms of scattering of free carriers by spacially slowly varying potential associated with oxide precipitates of varying size.

scholarly journals Characteristic temperature dependence of the4foccupancy in the Kondo systemCeSi2

2001 ◽  
Vol 63 (11) ◽  
Author(s):  
C. Grazioli ◽  
Z. Hu ◽  
M. Knupfer ◽  
G. Graw ◽  
G. Behr ◽  
...  
Keyword(s):  
Temperature Dependence ◽  
Characteristic Temperature ◽  
Characteristic Temperature Dependence

Viscoelasticity of dense suspensions of thermosensitive microgel mixtures undergoing colloidal gelation

Soft Matter ◽  
2018 ◽  
Vol 14 (9) ◽  
pp. 1596-1607 ◽  
Author(s):  
Saori Minami ◽  
Takumi Watanabe ◽  
Daisuke Suzuki ◽  
Kenji Urayama
Keyword(s):  
Temperature Dependence ◽  
Characteristic Temperature ◽  
Dense Suspensions ◽  
Characteristic Temperature Dependence

Viscoelasticity of dense suspensions of thermosensitive microgel mixtures exhibits characteristic temperature-dependence resulting from colloidal gelation.

Characterization of carbon aerogels by transport measurements

1993 ◽  
Vol 8 (8) ◽  
pp. 1875-1885 ◽  
Author(s):  
A.W.P. Fung ◽  
Z.H. Wang ◽  
K. Lu ◽  
M.S. Dresselhaus ◽  
R.W. Pekala
Keyword(s):  
Raman Scattering ◽  
Temperature Dependence ◽  
Nearest Neighbor ◽  
Negative Temperature ◽  
Carbon Aerogels ◽  
Free Carriers ◽  
Carbon Particles ◽  
Microcellular Foams ◽  
Temperature Coefficient Of Resistivity

Carbon aerogels are a special class of low-density microcellular foams. These materials are composed of interconnected carbon particles with diameters of approximately 10 nm. The temperature dependence of the dc electrical resistivity and magnetic susceptibility (χ) from 4 K to room temperature, magnetoresistance (MR) in a magnetic field up to 15 T, and Raman scattering were measured as a function of aerogel density. While Raman scattering measurements are not sensitive to variations in density, the χ data show that there are more free carriers in samples of higher density. Aerogel samples with different densities all show a negative temperature coefficient of resistivity and a positive MR. The less dense samples exhibit a stronger temperature dependence of resistivity and a stronger field dependence of the MR, indicating that with decreasing density and increasing porosity, charge carriers are more localized. Data analysis precludes variable-range hopping in favor of nearest-neighbor hopping and fluctuation-induced tunneling as the most likely conduction mechanisms for carbon aerogels.

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