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The change in electron mobility of n-Si with increasing the temperature which may be due to the inclusion of gLOphonon energy of 720 K, is presented. Under orientation of the uniaxial pressure X//[110]//J, g-transitions are attached in the directions [100] and [010]. The f-transitions are not completely removed from valleys located in the plane (100). In this case, there is no change in the slope of the dependence logρ vs. logT for the temperature range 77 to 450 K. So, no appreciable contribution of g-transitions to intervalley scattering occurs, while the observed is the decisive role of f-transitions to intervalley scattering. The results of measuring of the tensoresistivity effect for n-Si crystals under X//[001]//J are presented at these temperatures too.

Previously [

The analysis of experimental data of many works on the study of fand g-transitions in n-Si indicates that the discussion of their role in intervalley scattering is not finished until now. This is due to the fact that silicon possesses a sufficiently wide set of phonons, which can make sufficiently comparable contribution of electrons to the intervalley scattering [2-7].

The scattering between Δ_{1} valleys that are aligned along the non-equivalent directions is caused by f-transitions. In these processes the phonons from Σ line are involved. According to the selection rules the TOand LOphonons with Σ_{1} symmetry are involved. Electron-phonon scattering between the valleys that are aligned along Δ is named g-transitions. This scattering is caused by the transitions in which the phonons are involved. In silicon these are the LO-phonons of symmetry.

In [^{8} eV/cm. We used the direction of uniaxial pressure X//[

As known, “Intel Corporation” introduced n-MOS transistors with silicon uniaxial deformed in the direction [

For the investigation of the intervalley scattering of elec-

trons in n-Si at T = 77 ¸ 450 K the specimens had sufficiently low donor concentration and namely 4 × 10^{13} cm^{−3}. Sample dimensions were (0.7 × 0.7 × 10) mm^{3} for longitudinal investigation geometry. In all the cases the quantity E don’t over the limit of 0.5 V/cm. The accuracy of the X-ray method for determining the crystallographic orientation was ±15². After mounting a sample on the experimental setup the precision of its orientation with respect to the applied stress was not less than ±30². We used the installation for transport phenomena investigation under high uniaxial pressure described previously [

In this work we used the tensoresistivity (TR) effect at different directions of uniaxial pressure and temperature dependence of resistivity r = r(Т) in uniaxial deformed and undistorted crystal n-Si for the temperature range T = 77 ¸ 450 K. This temperature range covers the region of intrinsic conductivity of silicon crystals, so all conclusions about the impact of fand g-transitions are limited to the temperature at which the intrinsic conductivity sets in.

^{−2,3} at X = 0 (^{−1,6} (