14nm FinFET

Device Context and Integration Logic

The FCT SiON Deposition step is positioned in the FIN_CUT module after the formation of a carbon-doped oxide fill and before fin-cut lithography to establish a chemically and physically robust intermediate hard mask that stabilizes fin geometry during subsequent pattern transfer [P1].This layer provides etch selectivity and dimensional buffering between the underlying oxide fill and the aggressive anisotropic SiON etch used to define fin cuts, thereby pr…

• [High] Plasma-Induced Sidewall Damage: Excessive ion energy during plasma-enhanced deposition can create dangling bonds and defect states on fin sidewalls, increasing roughness and degrading subsequent etch uniformity, following the damage mechanisms identified in plasma-assisted thin-film deposition studies [P1].- [Medium] Non-Uniform Nitrogen/Oxygen Incorporation: Spatial or temporal variations in radical composition can lead to local stoichiometry differences within the SiON film, c…