Buried and Surface n-channel MOS Transistors in SOI

We compare buried- and surface-channel NMOS transistors made in SOI films. We show that buried channels can be used in SOI for improving the performances of the transistors. The kink is avoided. The mobility is increased by 20% as is the drain current. This can be obtained without drastically thinning the SOI film. This is important if we consider the technological problems related with very thin films, such as thickness uniformity and homogeneity, interface quality. However, improvements must be found in the short channel behaviour of the buried channels if we want to use them in the deep submicron range.