Proceedings Article | 30 August 2006
Proc. SPIE. 6324, Plasmonics: Nanoimaging, Nanofabrication, and their Applications II
KEYWORDS: Lithography, Finite-difference time-domain method, Polarization, Metals, Near field, Photomasks, Integrated optics, Polaritons, Nanolithography, Near field optics
The continuing size reduction of integrated circuits to nano dimensions requires the development of advanced
lithographic techniques. In order to obtain the desired feature sizes, it has become increasingly complex and high-cost to
use the established methods of optical projection lithography at short optical wavelengths. Surface-plasmon polariton
interference lithography (SPPIL) can provide a feasible way to achieve or approach the ultimate resolution for a certain
wavelength without requiring complicated and expensive large numerical aperture optics. But it demands the fabrication
of gratings with very fine period as a mask to realize contact printing, and the imaging quality is seriously dependent on
the structure and materials of the mask, the illuminating light, photoresist, etc. So the optimization of the technological
parameters is important to improve the imaging quality of nanolithography based on surface-plasmon polariton(SPP). In
this paper, the simulation of near-field distribution of SPPIL is performed using Finite Difference Time Domain FDTD
method, and the impacts of some technological conditions to the exposure field are analyzed including the polarization
state and wavelength of the illuminating light, the periodicity, thickness and slit width of the mask, and so on. The
simulation results show that, it is possible to fabricate good quality pattern with about 60nm features, with SPPIL using a
436nm-wavelength incident light.
