Ge-based NMOS device and method for fabricating the same

摘要

The embodiments of the present invention provide a Ge-based NMOS device structure and a method for fabricating the same. By using the method, double dielectric layers of germanium oxide (GeO2) and metal oxide are deposited between the source/drain region and the substrate. The present invention not only reduces the electron Schottky barrier height of metal/Ge contact, but also improves the current switching ratio of the Ge-based Schottky and therefore, it will improve the performance of the Ge-based Schottky NMOS transistor. In addition, the fabrication process is very easy and completely compatible with the silicon CMOS process. As compared with conventional fabrication method, the Ge-based NMOS device structure and the fabrication method in the present invention can easily and effectively improve the performance of the Ge-based Schottky NMOS transistor.

主权项

1. A Ge-based Schottky NMOS transistor, wherein, a germanium oxide layer and a metal oxide layer are deposited between a substrate and a source/drain region by depositing the germanium oxide layer over the substrate, depositing a metal oxide layer over the germanium oxide layer, and a metal source/drain is located over the metal oxide layer, wherein a ratio between the areal density of oxygen of metal oxide and that of GeO2 is less than 0.8.