|Title:||Atomic-layer doping of SiGe heterostructures for atomic-precision donor devices||Authors:||E. Bussmann
J. K. Gamble
J. C. Koepke
S. H. Huang
B. S. Swartzentruber
M. P. Lilly
M. S. Carroll
T. M. Lu
|Issue Date:||2018||Journal Volume:||1||Journal Issue:||6||Start page/Pages:||111959-111965||Source:||Physical Review Materials||Abstract:||
As a first step to porting scanning tunneling microscopy methods of atomic-precision fabrication to a strained-Si/SiGe platform, we demonstrate post-growth P atomic-layer doping of SiGe heterostructures. To preserve the substrate structure and elastic state, we use a T≤800 ° C process to prepare clean Si0.86Ge0.14 surfaces suitable for atomic-precision fabrication. P-saturated atomic-layer doping is incorporated and capped with epitaxial Si under a thermal budget compatible with atomic-precision fabrication. Hall measurements at T=0.3 K show that the doped heterostructure has R□=570±30Ω, yielding an electron density ne=2.1±0.1×1014cm-2 and mobility μe=52±3cm2V-1s-1, similar to saturated atomic-layer doping in pure Si and Ge. The magnitude of μe and the complete absence of Shubnikov-de Haas oscillations in magnetotransport measurements indicate that electrons are overwhelmingly localized in the donor layer, and not within a nearby buried Si well. This conclusion is supported by self-consistent Schrödinger-Poisson calculations that predict electron occupation primarily in the donor layer. © 2018 American Physical Society.
|ISSN:||24759953||DOI:||10.1103/physrevmaterials.2.066004||SDG/Keyword:||Atoms; Budget control; Crystal atomic structure; Hall mobility; Scanning tunneling microscopy; Silicon; Substrates; Atomic precision; Atomic-layer doping; Electron occupation; Hall measurements; Magneto-transport measurement; Shubnikov de-Haas oscillation; Strained-Si/SiGe; Substrate structure; Si-Ge alloys|
|Appears in Collections:||電機工程學系|
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.