Preparation method of accumulative type Si-NWFET (silicon-nanowire field effect transistor based on SOI (Silicon On Insulator)

The invention discloses a preparation method of an accumulative type Si-NWFET (silicon-nanowire field effect transistor based on an SOI (Silicon On Insulator). The preparation method comprises the following steps of: forming a silicon layer and a germanium-silicon layer on an SOI substrate; forming an active region and a source-drain region on an etching silicon layer and the germanium-silicon layer; forming silicon nanowires in the finned active region; forming a groove region and a grid and carrying out ion implantation on the source-drain region; forming an accumulative type PMOSFET; and depositing an interlayer isolated dielectric layer, and forming an accumulative type NMOSFET on the interlayer isolated dielectric layer. According to the preparation method disclosed by the invention, on the basis of the SOI substrate, a grid and a silicon lining layer in the lower-layer PMOSFET can be well isolated; the upper-layer semiconductor nanowire MOSFET and the lower-layer semiconductor nanowire MOSFET are isolat