US Patent 7187042 Backgated FinFET having different oxide thicknesses

A method of producing a backgated FinFET having different dielectric layer thickness on the front and back gate sides includes steps of introducing impurities into at least one side of a fin of a FinFET to enable formation of dielectric layers with different thicknesses. The impurity, which may be introduced by implantation, either enhances or retards dielectric formation.