Semiconductor device and method of forming the same

1. A semiconductor device comprising:

a semiconductor substrate having a first gate groove;

a first fin structure underneath a top of the first gate groove;

a second gate groove in the semiconductor substrate running generally parallel to said first gate groove;

a second fin structure underneath a top of the second gate groove;

a first gate insulating film that covers the first gate groove and a surface of the first fin structure;

a second gate insulating film that covers the second gate groove and a surface of the second fin structure;

a first gate electrode on the first gate insulating film in a lower portion of the first gate groove, the first gate electrode extending over the first fin structure;

a second gate electrode on the second gate insulating film in a lower portion of the second gate groove, the second gate electrode extending over the second fin structure;

a first diffusion region in the semiconductor substrate, the first diffusion region covering an upper portion of a first side of the first gate groove;

a second diffusion region in the semiconductor substrate, the second diffusion region covering a second side of the first gate groove, the second diffusion region also covering a second side of the second gate groove;

a third diffusion region in the semiconductor substrate covering an upper portion of a first side of the second gate groove,

wherein a bottom of the second diffusion region is shallower than a bottom of the first fin structure, and

wherein the bottom of the second diffusion region is deeper than a top of the first fin structure.

2. The semiconductor device according to claim 1 , wherein the first gate groove has a bottom that has a depth from a surface of the semiconductor substrate in the range from 150 nm to 200 nm, and the first fin structure has a height in the range from 10 nm to 40 nm.

3. The semiconductor device according to claim 1 , further comprising a plurality of first isolation regions in the semiconductor device, the plurality of first isolation regions defining active regions, the plurality of first isolation regions extending in a first direction,

wherein the first and second gate grooves extend in a second direction and across the active regions and the plurality of first isolation regions.