Optical properties of 2D fractional Talbot patterns under coherent EUV illumination. (21st August 2015)

• Record Type: Journal Article
• Authors: Kim, H; Li, W; Danylyuk, S; Brocklesby, W S; Marconi, M C; Juschkin, L
• Is Part Of: Journal of physics. Volume 48:Number 37(2015)
• Publication Date: 2015-08-21
• Subjects: extreme ultraviolet -- micro/nano-fabrication -- fractional Talbot effect -- interference lithography; Physics -- Periodicals; 530
• DOI: 10.1088/0022-3727/48/37/375101
• Languages: English
• ISSNs: 0022-3727

Abstract

Abstract: We investigate optical properties of (2D) fractional Talbot patterns under illumination with EUV laser light. The fractional Talbot effect, due to spatial frequency multiplication, can enable patterning of micro and nano-structures with various feature sizes using a micro-scale pitch mask. The experiment is performed with a free-standing mask fabricated by focused ion beam milling and a highly coherent illumination at 46.9 nm wavelength generated by a compact capillary discharge Ne-like Argon laser. As a result of spatial frequency multiplication, structure density of a square array of apertures in the mask was increased by a factor of up to 9 at the recording plane. The depth of field of the fractional Talbot images has been investigated using Fresnel diffraction analysis. Added field distribution complexity caused by asymmetry of the 2D arrays was observed both in simulation and in the experiment. This approach could be useful for sub-micron structuring of 2D patterns for various applications including among others the fabrication of photonic crystals, quantum dots, and also of submicron-electronic devices.