Semiconductor device and fabricating method thereof

Abstract

Semiconductor devices and a fabricating method therefore are disclosed. One method includes forming a buffer oxide layer and a buffer nitride layer on the top surface of a semiconductor substrate; forming a photoresist pattern on the pad nitride layer and forming a trench by etching the buffer nitride layer, the buffer oxide layer and the semiconductor substrate by a predetermined etch using the photoresist pattern as a mask; forming sidewall floating gates on the lateral faces of the trench; depositing polysilicon on the entire surface of the resulting structure; forming a gate electrode by patterning the polysilicon of the resulting structure; removing the buffer nitride layer and forming a poly oxide layer on the exposed part of the polysilicon of the gate electrode; forming source/drain regions by implanting impurities into the predetermined part of the resulting structure; injecting electric charges into the sidewall floating gates; and forming spacers on the lateral faces of the sidewall floating gates and the gate electrode.