Patent attributes
A method for forming FinFETs comprises forming a plurality of first fins and a plurality of second fins protruding over a substrate, wherein two adjacent first fins are separated from each other by a plurality of first isolation regions and two adjacent second fins are separated from each other by a plurality of second isolation regions. The method further comprises applying a first ion implantation process to the first isolation region, wherein dopants with a first polarity type are implanted in the first isolation region, applying a second ion implantation process to the second isolation region, wherein dopants with a second polarity type are implanted in the second isolation region and recessing the first isolation regions and the second isolation regions through an etching process.