Patent ID: 8748989

Claim:
A fin field effect transistor (FinFET) comprising: a substrate comprising a major surface; a plurality of first trenches having a first width and a first depth, each first trench of the plurality of first trenches extending downward from the substrate major surface to a first height, wherein a first space between adjacent first trenches defines a first fin; a plurality of second trenches having a second width and a second depth, the second width less than first width, each second trench of the plurality of second trenches extending downward from the substrate major surface to a second height greater than the first height, wherein a second space between adjacent second trenches defines a second fin; a first isolation structure partially filling each first trench of the plurality of first trenches; a second isolation structure partially filling each second trench of the plurality of second trenches, wherein a difference between a height of the first isolation structure and the first depth is substantially equal to a difference between a height of the second isolation structure and the second depth; wherein the first fin has a third width; and the second fin has a fourth width that is different from the third width.