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Nanolithography with metastable helium atoms in a high-power standing-wave light field

S. J. H. Petra·L. Feenstra·W. Hogervorst·W. Vassen
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Abstract

We have created periodic nanoscale structures in a gold substrate with a lithography process using metastable triplet helium atoms that damage a hydrofobic resist layer on top of the substrate. A beam of metastable helium atoms is transversely cooled and guided through an intense standing-wave light field. Compared to commonly used low-power optical masks, a high-power light field (saturation parameter of 10E7) increases the confinement of the atoms in the standing-wave considerably, and makes the alignment of the experimental setup less critical. Due to the high internal energy of the metastable helium atoms (20 eV), a dose of only one atom per resist molecule is required. With an exposure time of only eight minutes, parallel lines with a separation of 542 nm and a width of 100 nm (1/11th of the wavelength used for the optical mask) are created.

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S. J. H. Petra, L. Feenstra, W. Hogervorst, W. Vassen. 2003-08-19. Nanolithography with metastable helium atoms in a high-power standing-wave light field. https://doi.org/10.1007/s00340-003-1371-8

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