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arXiv · 1811.05192

Enhancement of optical response in nanowires by negative-tone PMMA lithography

Ilya Charaev·Andrew Dane·Akshay Agarwal·Karl K. Berggren
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Abstract

The method of negative-tone-PMMA electron-beam lithography is investigated to improve the performance of nanowire-based superconducting detectors. Using this approach, the superconducting nanowire single-photon detectors (SNSPDs) have been fabricated from thick 5-nm NbN film sputtered at the room temperature. To investigate the impact of this process, SNSPDs were prepared by positive-tone and negative-tone-PMMA lithography, and their electrical and photodetection characteristics at 4.2 K were compared. The SNSPDs made by negative-tone-PMMA lithography show higher critical-current density and higher photon count rate at various wavelengths. Our results suggest a higher negative-tone-PMMA technology may be preferable to the standard positive-tone-PMMA lithography for this application.

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Ilya Charaev, Andrew Dane, Akshay Agarwal, Karl K. Berggren. 2018-11-13. Enhancement of optical response in nanowires by negative-tone PMMA lithography. https://doi.org/10.1109/tasc.2019.2898677

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