Measurements of low field mobility in ultra-thin SOI n- and p-MOSFETs
Low-field electron and hole effective mobilities (?eff) of ultra-thin SOI n- and p-MOSFETs, down to a silicon thickness TSi of approximately 5 nm, have been measured at different temperatures using a special test structure able to circumvent parasitic resistance effects. At large inversion densities (Ninv), ultra-thin SOI exhibit higher mobility than heavily doped bulk MOS and a weak dependence of mobility on silicon thickness. However, at small Ninv the mobility is clearly reduced for decreasing TSi, due to enhanced phonon scattering in the thin quantum well.
low field mobility mobility soi