Large area periodic, systematically changing, multishape nanostructures by laser interference lithography and cell response to these topographies

Abstract

Hamilton, Douglas W.; and Mittler, Silvia, "Large area periodic, systematically changing, multishape nanostructures by laser interference lithography and cell response to these topographies" (2013 Abstract. The fabrication details to form large area systematically changing multishape nanoscale structures on a chip by laser interference lithography (LIL) are described. The feasibility of fabricating different geometries including dots, ellipses, holes, and elliptical holes in both x-and y-directions on a single substrate is shown by implementing a Lloyd's interferometer. The fabricated structures at different substrate positions with respect to exposure time, exposure angle and associated light intensity profile are analyzed. Experimental details related to the fabrication of symmetric and biaxial periodic nanostructures on photoresist, silicon surfaces, and ion milled glass substrates are presented. Primary rat calvarial osteoblasts were grown on ion-milled glass substrates with nanotopography with a periodicity of 1200 nm. Fluorescent microscopy revealed that cells formed adhesions sites coincident with the nanotopography after 24 h of growth on the substrates. The results suggest that laser LIL is an easy and inexpensive method to fabricate systematically changing nanostructures for cell adhesion studies. The effect of the different periodicities and transition structures can be studied on a single substrate to reduce the number of samples significantly.

Multiexposure laser interference lithography

“…In order to test our simulation software and photoresist nanofiber production, we fabricated single and double exposed structures similar to the previously demonstrated structures by Ertorer et al 30 Figure 3(a) illustrates an electron microscopy image of a single exposure sample and Fig. 3(b) shows the corresponding simulation.…”

“…30 show that by increasing the number of exposures and varying exposure times, a wide variety of symmetric patterns with very fine structures and sophisticated geometry can be created. 30 show that by increasing the number of exposures and varying exposure times, a wide variety of symmetric patterns with very fine structures and sophisticated geometry can be created.…”

Determination of beam incidence conditions based on the analysis of laser interference patterns

“…LIL is also a flexible method capable of producing various sub-wavelength fringe and dot structures in the cases of two-, three-and four-beam laser interference [3][4][5][6][7][8]. Recently, researchers reported that a wide variety of applications were achieved by LIL.…”

Tailored Fringed Platforms Produced by Laser Interference for Aligned Neural Cell Growth

“…One way to overcome these problems while preserving high reproducibility and versatility is the use of lithographic approaches. [4,6,7,9,23] However, they are generally multistep processes that are costly and time consuming. [24] A different approach that has been recently proposed and successfully applied to graphene is the combination of ultrashort laser pulses with a digital micromirror device.…”