Transistor structure and manufacturing method thereof

A transistor structure, comprising:

• a substrate;
• a gate structure located on the substrate;
• source/drain regions located in the substrate aside the gate structure;
• first contact doped regions located in the substrate aside the gate structure, wherein the source/drain regions are located in the first contact doped regions, and a dopant of the first contact doped regions comprises a group IVA element;
• and
• second contact doped regions located in the first contact doped regions, wherein a depth of the second contact doped regions is greater than a depth of the source/drain regions, wherein
• the first contact doped regions and the second contact doped regions are not located directly below the gate structure.

A manufacturing method of a transistor structure, comprising:

• providing a substrate;
• forming a gate structure on the substrate;
• forming first pocket doped regions in the substrate aside the gate structure, wherein a dopant of the first pocket doped regions comprises a group IVA element;
• forming second pocket doped regions in the substrate aside the gate structure, wherein a depth of the second pocket doped regions is greater than a depth of the first pocket doped regions;
• forming source/drain extension regions in the first pocket doped regions;
• forming source/drain regions in the substrate aside the gate structure, wherein the source/drain extension regions are located between the source/drain regions and the gate structure;
• forming first contact doped regions in the substrate aside the gate structure, wherein the source/drain regions are located in the first contact doped regions, and a dopant of the first contact doped regions comprises the group IVA element;
• and
• forming second contact doped regions in the first contact doped regions, wherein a depth of the second contact doped regions is greater than a depth of the source/drain regions, wherein
• the first contact doped regions and the second contact doped regions are not located directly below the gate structure.