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DOE OSTI · 2584414

Direct Observation of 2DEG States in Shallow Si:Sb δ-Layers

Strand, Frode S. [Norwegian University of Science and Technology (NTNU), Trondheim (Norway)] (ORCID:0009000949085432)·Cooil, Simon P. [University of Oslo (UiO) (Norway)]·Campbell, Quinn T. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000313773769)·Flounders, John J. [Aarhus University (Denmark)] (ORCID:0009000390986183)·Røst, Håkon I. [University of Bergen (Norway)] (ORCID:0000000218538349)·Åsland, Anna Cecilie [Norwegian University of Science and Technology (NTNU), Trondheim (Norway)] (ORCID:0000000328376133)·Skarpeid, Alv Johan [University of Oslo (UiO) (Norway)]·Stalsberg, Marte P. [University of Oslo (UiO) (Norway)]·Hu, Jinbang [Norwegian University of Science and Technology (NTNU), Trondheim (Norway)] (ORCID:0000000222328440)·Bakkelund, Johannes [Norwegian University of Science and Technology (NTNU), Trondheim (Norway)]·Bjelland, Victoria [Norwegian University of Science and Technology (NTNU), Trondheim (Norway)]·Preobrajenski, Alexei B. [Lund University (Sweden)] (ORCID:0000000294447844)·Li, Zheshen [Aarhus University (Denmark)]·Bianchi, Marco [Aarhus University (Denmark); Elettra - Sincrotrone Trieste (Italy)]·Miwa, Jill A. [Aarhus University (Denmark)]·Wells, Justin W. [Norwegian University of Science and Technology (NTNU), Trondheim (Norway); University of Oslo (UiO) (Norway)] (ORCID:000000016366366X)
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Abstract

We investigate the electronic structure of high-density layers of Sb dopants in a silicon host, so-called Si:Sb δ-layers. We show that, in spite of the known challenges in producing highly confined Sb δ-layers, sufficient confinement is created such that the lowest conduction band states (Γ states, studied in depth in other silicon δ-layers), become occupied and can be observed using angle-resolved photoemission spectroscopy. The electronic structure of the Si:Sb δ-layers closely resembles that of Si:P systems, where the observed conduction band is near-parabolic and slightly anisotropic in the k ∥ plane. The observed Γ state extends ∼1 nm in the out-of-plane direction, which is slightly wider than the 1/3 monolayer thick dopant distribution. This is caused by a small segregation of the dopant layer, which is nevertheless minimal when comparing with earlier published attempts. Our results serve to demonstrate that Sb is still a feasible dopant alternative for use in the semiconductor δ-layer platform, providing similar electronic functionality to Si:P systems. Additionally, it has the advantages of being less expensive, more controllable, safer to handle, and more compatible with industrial patterning techniques. Si:Sb is therefore a viable platform for emerging quantum device applications.

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Strand, Frode S. [Norwegian University of Science and Technology (NTNU), Trondheim (Norway)] (ORCID:0009000949085432), Cooil, Simon P. [University of Oslo (UiO) (Norway)], Campbell, Quinn T. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000313773769), Flounders, John J. [Aarhus University (Denmark)] (ORCID:0009000390986183), Røst, Håkon I. [University of Bergen (Norway)] (ORCID:0000000218538349), Åsland, Anna Cecilie [Norwegian University of Science and Technology (NTNU), Trondheim (Norway)] (ORCID:0000000328376133), Skarpeid, Alv Johan [University of Oslo (UiO) (Norway)], Stalsberg, Marte P. [University of Oslo (UiO) (Norway)], Hu, Jinbang [Norwegian University of Science and Technology (NTNU), Trondheim (Norway)] (ORCID:0000000222328440), Bakkelund, Johannes [Norwegian University of Science and Technology (NTNU), Trondheim (Norway)], Bjelland, Victoria [Norwegian University of Science and Technology (NTNU), Trondheim (Norway)], Preobrajenski, Alexei B. [Lund University (Sweden)] (ORCID:0000000294447844), Li, Zheshen [Aarhus University (Denmark)], Bianchi, Marco [Aarhus University (Denmark); Elettra - Sincrotrone Trieste (Italy)], Miwa, Jill A. [Aarhus University (Denmark)], Wells, Justin W. [Norwegian University of Science and Technology (NTNU), Trondheim (Norway); University of Oslo (UiO) (Norway)] (ORCID:000000016366366X). 2025-01-08. Direct Observation of 2DEG States in Shallow Si:Sb δ-Layers. https://doi.org/10.1021/acs.jpcc.4c07331

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