Trim photomask providing enhanced dimensional trimming and methods for fabrication and use thereof

Abstract

A trim mask is used in conjunction with an additional mask for forming a patterned photoresist layer while using a two-step two-mask photoexposure method. The trim mask is used after exposing a blanket photoresist layer with the other mask. The trim mask comprises a transparent substrate. The trim mask also comprises patterned opaque layer and an adjoining patterned attenuated layer located exposed adjoining the patterned opaque layer and coincident with a latent images formed using the additional mask. The trim mask assists in addressing location dependent critical dimension variability when forming a patterned photoresist layer from the blanket photoresist layer or for creating uniform sub-lithographic imaging not possible with conventional lithographic techniques, including alternating phase shift lithography.

Dependencies are inferred from the claim text.