Imaging and registration of buried atomic-precision donor devices using scanning capacitance microscopy

TL;DR

This paper demonstrates that scanning capacitance microscopy can image buried atomic-precision donor nanostructures in silicon, enabling accurate alignment of metal contacts for nanoelectronic device fabrication.

Contribution

It introduces a novel technique using SCM to image buried nanostructures and align metal contacts with 300 nm accuracy, advancing atomic-precision device assembly.

Findings

SCM successfully images buried donor nanostructures.

Metal contacts aligned with 300 nm accuracy.

Transport measurements confirm contact placement.

Abstract

We show that a scanning capacitance microscope (SCM) can image buried delta-doped donor nanostructures fabricated in Si via a recently developed atomic-precision scanning tunneling microscopy (STM) lithography technique. A critical challenge in completing atomic-precision nanoelectronic devices is to accurately align mesoscopic metal contacts to the STM defined nanostructures. Utilizing the SCMs ability to image buried dopant nanostructures, we have developed a technique by which we are able to position metal electrodes on the surface to form contacts to underlying STM fabricated donor nanostructures with a measured accuracy of 300 nm. Low temperature (T=4K) transport measurements confirm successful placement of the contacts to the donor nanostructures.