Abstract: The performance of NMOS and PMOS regions of integrated circuits is improved. Embodiments of the invention include forming a first dielectric layer optimized for n-doped regions over the n-doped regions and forming a second dielectric layer optimized for p-doped regions over p-doped regions.

Abstract: Defective contact plug fills can be detected by applying an etching solution, which in some embodiments preferentially etches in the <111> direction. The etching solution is some embodiments may also produce a characteristic type of undercutting underneath the contact plug fill. Contact plug fills with defects in them have undercutting underneath as a result of the etchant exposure, while defective contact plug fills have no such undercutting. The contact plug fills that are now undercut by etching exposure are unable to dissipate surface charge or surface applied potential and can be detected using voltage contrast methods or conventional electrical testing techniques, for example.