Electron mobility of thin layer SOI MOSFETs in accumulation-mode

This paper reports the studies of the electron mobility in accumulation-mode planar double gate Silicon-on-Insulator metal-oxide-semiconductor field-effect transistors (SOI MOSFETs). Dependencies of the mobility on the excess carriers μ(N_e) were found in the channels, which were induced by the back gate. The top gate voltage was used to change the state of silicon from the surface. The value of mobility μ was shown to vary in the range 820 cm²/V·s to 160 cm²/V·s when Ne increases from 3·10¹¹ cm^-2 to 10¹³ cm^-2. The mobility also changes when the state of the surface SOI layer varies from inversion to accumulation. It was shown that μ(N_e) can be approximated by the power function μ(N_e)~N_e^-n. Values of index n were found for different the surface state of silicon.