Programmable nanolithography

Contacts: 
Philip Trøst Kristensen, ptkr@fotonik.dtu.dk
Jakob Rosenkrantz de Lasson, jrdl@fotonik.dtu.dk
Jesper Mørk, jesm@fotonik.dtu.dk  

Top: Sketch of the proposed nanolithography setup. Depending on polarization and wavelength of the plane wave illumination, the resist is exposed in different patterns. Bottom: Example calculations showing different intensity patterns of the resulting light field - the metal nanoparticles (white dots) are spaced by 75 nm. Pictures from Ref. [1].

Photolithography is widely used in industrial micro and nanofabrication, but the smallest possible feature sizes are limited by the wavelength of the laser source. As an alternative to traditional photolithography, researchers have proposed the use of small arrays of metal nanoparticles [1]. Due to different resonances in the metal nanoparticle arrays, this approach leads to nanometer sized hotspots when illuminated at optical wavelengths.

In this project we will set up a point-scattering calculation based on the electromagnetic Green's tensor and use it to calculate light scattering off metal nanoparticles. Using this model, we will critically investigate the viability of an approach based on arrays of metal nanoparticles for nanolithography.

This is an ambitious project that is intended for students with a solid interest in computer simulations and electromagnetics. Knowledge of Matlab will be an advantage, but is not a requirement.

[1]: A. F. Koenderink et al. "Programmable nanolithography with plasmon nanoparticles", Nano Letters 7, 745-749 (2007).