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arXiv · 2008.12054

Sub-50 nm focusing of 405 nm laser by hemispherical silicon nanolens

Zhong Wang·Weihua Zhang
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Abstract

In this work, we study the light focusing behaviors of sub-micron Si hemispherical nanolens in theory. Results show that the width and depth of the focus spot light at 405 nm can reach 42 nm (approximately {\lambda}/10) and 20 nm ({\lambda}/20), respectively. Theoretical analysis indicates that this nano-focusing phenomenon comes from two reasons, the high refractive index of Si and the sub-micro size of the lens which considerably decrease the influence of material losses. The focusing capability of Si nanolens is comparable with current EUV technique but with a low cost, providing an alternative approach towards super-resolution photolithography and optical microscopy.

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Zhong Wang, Weihua Zhang. 2020-08-27. Sub-50 nm focusing of 405 nm laser by hemispherical silicon nanolens. https://doi.org/10.1364/josab.408866

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