Semiconductor device and method of fabricating the same

A method of fabricating a semiconductor device, comprising:

• providing a substrate;
• forming a plurality of recesses in the substrate;
• forming a first gate dielectric material on the substrate and in the plurality of recesses;
• at least partially removing the first gate dielectric material on the substrate between the plurality of recesses to form a trench;
• forming a second gate dielectric material in the trench;
• forming a gate conductive layer on the second gate dielectric material, and forming a plurality of spacers on sidewalls of the gate conductive layer;
• removing a portion of the first gate dielectric material, so that the remaining first gate dielectric material and the second gate dielectric material form a gate dielectric layer, wherein the gate dielectric layer comprises:
• a body part;
• and
• a first hump part, located at a first edge of the body part, wherein a thickness of the first hump part is greater than a thickness of the body part;
• and
• forming a plurality of doped regions in the substrate at two sides of the plurality of spacers.