Vertical Si-Metal-Oxide-Semiconductor Field Effect Transistors with Channel Lengths of 50 nm by Molecular Beam Epitaxy

Abstract

The growth conditions in molecular beam epitaxy (MBE) were studied for the fabrication of vertical Si-metal-oxide-semiconductor field effect transistors (MOSFET) with channel lengths down to 50 nm. The short channel length imposes severe constraints on the doping profile. MBE growth provided a steepness of 10 nm/dec for boron and 2 nm/dec for antimony. The sharpness of the doping profile was sustained throughout the process by keeping all process temperatures below 700° C. The high crystal quality and the well-defined doping profile was verified by the good performance of a triangular barrier diode. A vertical n-MOSFET with an estimated channel length of 50 nm was grown. The drain and gate characteristics were discussed for a source drain voltage regime from U sd=0 V to 1 V.