Spectroscopy of a Deterministic Single-Donor Device in Silicon
Date of this Version5-1-2012
We present a single electron transistor (SET) based on an individual phosphorus dopant atom in an epitaxial silicon environment. Using scanning tunneling microscope (STM) hydrogen lithography, the single impurity is deterministically placed with a spatial accuracy of ±1 lattice site within a donor-based transport device. Low temperature transport measurements confirm the presence of the single donor and show that the donor charge state can be precisely controlled via gate voltages. We observe a charging energy that is remarkably similar to the value expected for isolated P donors in bulk silicon, which is in sharp contrast to previous experiments on single-dopant transport devices. We show that atomistic modeling can fully capture the effects of the highly-doped transport electrodes on the electronic states of the donor, thus highlighting the high level of control over the electrostatic device properties afforded by a deterministic single donor architecture. Our fabrication method therefore opens the door for the realization of a scalable donor-based qubit architecture in silicon.
Nanoscience and Nanotechnology