Semiconductor Structure and Method for Manufacturing the Same

A method for manufacturing a semiconductor structure, comprising:

• a) providing an SOI substrate and covering a part of said SOI substrate with a mask (400), the part of said SOI substrate covered by the mask being the area that is predetermined for forming a gate line;
• b) etching a SOI layer (100) and a BOX layer (110) of said SOI substrate on both sides of said mask (400) to form a trench (140) exposing the BOX layer (110), said trench (140) partially entering into the BOX layer (110);
• c) forming a stressed layer (160) by filling up a part of said trench (140);
• d) forming a semiconductor layer (150) to cover the stressed layer (160) in the trench (140);
• and
• e) removing the mask to expose the part of said SOI substrate covered by the mask and forming a gate structure (200) thereon.

A semiconductor structure comprising an SOI substrate, a gate structure (200), a stressed layer (160) and a semiconductor layer (150), wherein

• the SOI substrate includes a SOI layer (100) and a BOX layer (110);
• the gate structure (200) is formed on the SOI layer (100);
• the stressed layer (160) is formed in the SOI substrate on both sides of the gate structure (200) to contact the BOX layer (110) and extend into the BOX layer (110), and the upper surface of the stressed layer (160) is lower than the lower surface of the gate structure (200);
• and the stressed layer (160) is covered by the semiconductor layer (150) and the semiconductor layer (150) is in contact with the SOI layer (100).