Fin field effect transistor integrated circuits and methods for producing the same are provided. A fin field effect transistor integrated circuit includes a plurality of fins extending from a semiconductor substrate. Each of the plurality of fins includes a fin sidewall, and each of the plurality of fins extends to a fin height such that a trough with a trough base is defined between adjacent fins. A second dielectric is positioned within the trough, where the second dielectric directly contacts the semiconductor substrate at the trough base. The second dielectric extends to a second dielectric height less than the fin height such that protruding fin portions extend above the second dielectric. A first dielectric is positioned between the fin sidewall and the second dielectric.