Impact of process parameters on pattern formation in the maskless plasmonic computational lithography

• We model and simulate a maskless plasmonic lithography (MPL) for 15-nm critical dimension (CD).
• The near-field intensity of aperture shapes is described due to aperture parameters and number of layers by using a scattering matrix (S-matrix) analysis method and the finite difference time domain (FDTD) method.
• The most dominant parameter of aperture in impact of MPL parameters on pattern formation is gap size of bowtie in MPL by using Taguchi method.

The extraordinary optical transmission through a sub-wavelength size metal-aperture and metamaterials has been tremendous interests for the untilization of the surface plasmon polariton (SPP). Its technology, however, is hard to apply for the optical lithography process. In this study, a maskless plasmonic lithography (MPL) is modeled and simulated for 15-nm critical dimension (CD). The near-field intensity with the plasmonic phenomena of aperture shapes is described due to aperture parameters by using a scattering matrix (S-matrix) analysis method and the finite difference time domain (FDTD) method. MPL parameters of bowtie structures are optimized and improved for the imperfection of the resist pattern. The most dominant parameter on CD is gap size of bowtie by Taguchi method.