Abstract: Method for using chromeless phase shift lithography (CPL) masks to pattern contacts corresponding CPL masks. The method for patterning contacts includes illuminating a CPL mask comprising a reticle having plurality of phase-shifting features interspersed with non-phase-shifting areas with a short wavelength light source, wherein the phase-shifting features are configured in a pattern corresponding to a target pattern of the contacts on the semiconductor substrate. Phase-shifted and non-phase-shifted light passing through the reticle is the projected as an aerial image onto a layer of a negative tone resist applied over the semiconductor substrate to pattern the contacts in the resist. The phase-shifting features may comprise recesses or mesas, and cause light passing therethrough to be phase-shifted in phase approximately 180° from light passing through non-phase-shifting areas of the mask.

Abstract: Method for using chromeless phase shift lithography (CPL) masks to pattern contacts corresponding CPL masks. The method for patterning contacts includes illuminating a CPL mask comprising a reticle having plurality of phase-shifting features interspersed with non-phase-shifting areas with a short wavelength light source, wherein the phase-shifting features are configured in a pattern corresponding to a target pattern of the contacts on the semiconductor substrate. Phase-shifted and non-phase-shifted light passing through the reticle is the projected as an aerial image onto a layer of a negative tone resist applied over the semiconductor substrate to pattern the contacts in the resist. The phase-shifting features may comprise recesses or mesas, and cause light passing therethrough to be phase-shifted in phase approximately 180° from light passing through non-phase-shifting areas of the mask.