Electron mobility in the inversion layers of fully depleted SOI films

The dependences of the electron mobility $\mu_{\operatorname{eff}}$ in the inversion layers of fully depleted double–gate silicon-on-insulator (SOI) metal–oxide–semiconductor (MOS) transistors on the density $N_e$ of induced charge carriers and temperature $T$ are investigated at different states of the SOI film (inversion–accumulation) from the side of one of the gates. It is shown that at a high density of induced charge carriers of $N_{e}>$ 6 $\cdot$ 10$^{12}$ cm$^{-2}$ the $\mu_{\operatorname{eff}}(T)$ dependences allow the components of mobility $\mu_{\operatorname{eff}}$ that are related to scattering at surface phonons and from the film/insulator surface roughness to be distinguished. The $\mu_{\operatorname{eff}}(N_e)$ dependences can be approximated by the power functions $\mu_{\operatorname{eff}}(N_{e})\propto N_{e}^{-n}$. The exponents $n$ in the dependences and the dominant mechanisms of scattering of electrons induced near the interface between the SOI film and buried oxide are determined for different $N_e$ ranges and film states from the surface side.