Mask absorber material dependence of 2D OPC in ArF high NA lithography

Abstract

Rigorous optical proximity correction (OPC) for 3D reticle effects is critical to the success of 193nm wavelength immersion lithography implementation. The impact of 2D and 3D mask polarization and shadowing effects to 2D imaging in ultra high Numerical Aperture (NA) low-k1 imaging is assessed by simulation. An end-to-end (ETE) dense line 2D feature of various embedded (attenuated) phase shift mask (ePSM) with various material of film stack is studied. Line-end pullback is shown correlated with mask shadowing under TE-polarized OAI. Polarized OAI phase calibrated thinner mask absorber provides less shadowing, better 2D imaging window, and enables further scaling of mask feature patterning.

Deep subwavelength mask assist features and mask errors printability in high NA lithography

“…As the vectorial imaging effects increases significantly in high NA immersion lithography [1], the printability of mask defect and SRAF will depend on the composite effects of illumination vectors, Wood/Rayleigh resonance anomaly [1], mask material dependent 2-D feature proximity [2], optical proximity correction (OPC) features, mask topographic shadowing [2], effective mask glass trenching [3], and even pellicle membrane [1,4]. The rule of thumb for defect printability threshold band for conventional masks [5], will require thorough study to re-investigate the multi-parameter space in the high-NA imaging landscape.…”