Semiconductor device including a multigate transistor formed with fin structure

A semiconductor device, comprising:

• a first fin, a second fin, a third fin, a fourth fin and a fifth fin, wherein each of the first through fifth fins protrude from a substrate in a first direction and space apart from one another in a second direction;
• and
• a first trench, a second trench, a third trench and a fourth trench, wherein the first trench defines the first and second fins, the second trench defines the second and third fins, the third trench defines the third and fourth fins, and the fourth trench defines the fourth and fifth fins,
• wherein a first difference between a first depth of the first trench and a third depth of the third trench are different from a second difference between a second depth of the second trench and a fourth depth of the fourth trench.

A semiconductor device, comprising:

• a first fin structure, a second fin structure, and a third fin structure protruding from a substrate, extending in a first direction, and spaced apart from each other in a second direction, wherein the first fin structure is disposed between the second fin structure and the third fin structure;
• a first trench to space the first fin structure and the second fin structure;
• and
• a second trench to space the first fin structure and the third fin structure,
• wherein the first fin structure comprises a first base fin protruding from the substrate, a first fin and a second fin protruding from the first base fin and spaced apart from each other in the second direction, and a third trench to define the first fin and the second fin,
• wherein a first width of the first trench is smaller than a second width of the second trench, and
• a first depth of the first trench is smaller than a second depth of the second trench.