STM-induced desorption and lithographic patterning of Cl-Si(100)-(2x1)

TL;DR

This study explores STM-induced chlorine desorption on Si(100) surfaces, demonstrating lithographic patterning techniques and analyzing how parameters affect pattern resolution, aiming to expand halogen-based chemistries for semiconductor device fabrication.

Contribution

It introduces chlorine as a resist for STM lithography on silicon, enabling atomic precision patterning and broadening halogen chemistry options for device manufacturing.

Findings

Pattern line widths increase with bias voltage and electron dose.

Both large-area and atomic-scale patterning are achievable.

Chlorine, bromine, and iodine resist materials expand fabrication possibilities.

Abstract

We investigated STM-induced chlorine desorption and lithographic patterning of Cl-terminated Si(100)-(2x1) surfaces at sample temperatures from 4 K to 600 K. STM lithography has previously focused on hydrogen-based chemistry for donor device fabrication. Here, to develop halogen-based chemistries for fabricating acceptor-based devices, we substituted the hydrogen resist with chlorine. Lithographic patterning was explored using both field emission patterning to desorb chlorine from large areas as well as atomic precision patterning to desorb chlorine along one to two dimer rows at a time. We varied the experimental parameters for lithographic patterning and found a positive correlation between pattern line widths and both sample bias voltage and total electron dose. Finally, the use of chlorine, bromine, and iodine as lithographic resists to broaden the range of available chemistries for future device fabrication utilizing halogen-based dopant precursors is discussed.