Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Center for Integrated Nanotechnologies
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Center for Computing Research
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
National Taiwan Univ., Taipei (Taiwan). Dept. of Electrical Engineering and Graduate Inst. of Electronic Engineering; National Nano Device Laboratories, Hsinchu (Taiwan)
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 Si0.86 Ge0.14 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 $$\square$$ = 570 ± 30 Ω , yielding an electron density ne = 2.1 ± 0.1 × 1014 cm-2 and mobility μe = 52 ± 3 cm2 V-1 s-1, similar to saturated atomic-layer doping in pure Si and Ge. The magnitude of μ e 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. Finally, this conclusion is supported by self-consistent Schrödinger-Poisson calculations that predict electron occupation primarily in the donor layer.
Bussmann, E., Gamble, John King, Koepke, J. C., Laroche, D., Huang, S. H., Chuang, Y., Li, J. -Y., Liu, C. W., Swartzentruber, B. S., Lilly, M. P., Carroll, M. S., & Lu, T. -M. (2018). Atomic-layer doping of SiGe heterostructures for atomic-precision donor devices. Physical Review Materials, 2(6). https://doi.org/10.1103/PhysRevMaterials.2.066004
Bussmann, E., Gamble, John King, Koepke, J. C., et al., "Atomic-layer doping of SiGe heterostructures for atomic-precision donor devices," Physical Review Materials 2, no. 6 (2018), https://doi.org/10.1103/PhysRevMaterials.2.066004
@article{osti_1464188,
author = {Bussmann, E. and Gamble, John King and Koepke, J. C. and Laroche, D. and Huang, S. H. and Chuang, Y. and Li, J. -Y. and Liu, C. W. and Swartzentruber, B. S. and Lilly, M. P. and others},
title = {Atomic-layer doping of SiGe heterostructures for atomic-precision donor devices},
annote = {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 Si0.86 Ge0.14 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 $\square$ = 570 ± 30 Ω , yielding an electron density ne = 2.1 ± 0.1 × 1014 cm-2 and mobility μe = 52 ± 3 cm2 V-1 s-1, similar to saturated atomic-layer doping in pure Si and Ge. The magnitude of μ e 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. Finally, this conclusion is supported by self-consistent Schrödinger-Poisson calculations that predict electron occupation primarily in the donor layer.},
doi = {10.1103/PhysRevMaterials.2.066004},
url = {https://www.osti.gov/biblio/1464188},
journal = {Physical Review Materials},
issn = {ISSN 2475-9953},
number = {6},
volume = {2},
place = {United States},
publisher = {American Physical Society (APS)},
year = {2018},
month = {06}}
