Semiconductor structure capable of improving row hammer effect in dynamic random access memory and fabrication method thereof

A method for fabricating a semiconductor structure, comprising:

• providing a semiconductor substrate having a first conductivity type;
• forming at least one active area on the semiconductor substrate, wherein a major axis of the active area extends along a first direction;
• performing a first oblique ion implantation process to form a first doped region having a second conductivity type above a first depth on an end surface of the active area;
• performing a second oblique ion implantation process to form a second doped region having a third conductivity type above a second depth on the end surface of the active area, wherein the third conductivity type and the second conductivity types are opposite to each other, so that a localized doped region having the second conductivity type is formed between the first depth and the second depth;
• and
• forming a trench isolation structure around the active area and adjacent to the end surface of the active area.