Valence Band Offset Measurements on Thin Silicon-on-Insulator MOSFETs

The effect of quantum confinement in thin silicon-on-insulator double-gate MOSFETs has been directly determined from subthreshold current measurements for the first time. By comparing temperature-dependent subthreshold characteristics of p-type devices with different silicon layer thicknesses, the offset in the valence band edge induced by spatial carrier confinement in these very thin silicon layers was measured electrically. Changes in the band structure are important for future CMOS devices such as FinFETs.