TY - JOUR

T1 - Controllable CaF2 Nanosized Stripe Arrays on Si(001) Studied by X-ray and Electron Diffraction

AU - Suturin, Sergey M.

AU - Fedorov, Vladimir V.

AU - Korovin, Alexander M.

AU - Valkovskiy, Gleb A.

AU - Tabuchi, Masao

AU - Sokolov, Nikolai S.

N1 - Suturin, S.M.; Fedorov, V.V.; Korovin, A.M.; Valkovskiy, G.A.; Tabuchi, M.; Sokolov, N.S. Controllable CaF2 Nanosized Stripe Arrays on Si(001) Studied by X-ray and Electron Diffraction. Surfaces 2021, 4, 97-105. https://doi.org/10.3390/surfaces4020012

PY - 2021/6

Y1 - 2021/6

N2 - Adding uniaxial in-plane anisotropy to the otherwise four-fold Si(001) surface has for a long time been known to be possible via epitaxial deposition of a single atomic layer of calcium fluoride (CaF2), which forms an array of micron-long (110) oriented parallel stripes when the substrate temperature during the growth is kept in the range of 700-800 degrees C. As shown in the present paper, a fine control over dimensions and periodicity of the stripe array is possible through the introduction of a two-stage growth process at which the (110) orientation of the fluorite layer is settled at the high-temperature nucleation stage, while the stripes of controllable dimensions are formed at the second stage. By varying the substrate temperature at the second growth stage in the range of 800-400 degrees C, the stripe arrays with a periodicity from above 30 nm to below 10 nm can be fabricated with the height variation changing accordingly. Such variability can be of use in the applications in which the striped fluorite surface is used to influence the anisotropy of other functional (e.g., magnetically ordered or organic) materials grown on top. While large CaF2 stripes can be easily characterized by direct space techniques such as atomic force microscopy, the study of the shape and in-plane correlation between the stripes of a much smaller size is most effectively achieved through the use of grazing incidence reciprocal space techniques applied in the present paper. The discussed universal approach to 3D reciprocal space mapping utilizing scattering of X-rays and high-energy electrons offers a complementary way to study samples with arrays of long and narrow one-dimensional stripes at their surface.

AB - Adding uniaxial in-plane anisotropy to the otherwise four-fold Si(001) surface has for a long time been known to be possible via epitaxial deposition of a single atomic layer of calcium fluoride (CaF2), which forms an array of micron-long (110) oriented parallel stripes when the substrate temperature during the growth is kept in the range of 700-800 degrees C. As shown in the present paper, a fine control over dimensions and periodicity of the stripe array is possible through the introduction of a two-stage growth process at which the (110) orientation of the fluorite layer is settled at the high-temperature nucleation stage, while the stripes of controllable dimensions are formed at the second stage. By varying the substrate temperature at the second growth stage in the range of 800-400 degrees C, the stripe arrays with a periodicity from above 30 nm to below 10 nm can be fabricated with the height variation changing accordingly. Such variability can be of use in the applications in which the striped fluorite surface is used to influence the anisotropy of other functional (e.g., magnetically ordered or organic) materials grown on top. While large CaF2 stripes can be easily characterized by direct space techniques such as atomic force microscopy, the study of the shape and in-plane correlation between the stripes of a much smaller size is most effectively achieved through the use of grazing incidence reciprocal space techniques applied in the present paper. The discussed universal approach to 3D reciprocal space mapping utilizing scattering of X-rays and high-energy electrons offers a complementary way to study samples with arrays of long and narrow one-dimensional stripes at their surface.

KW - calcium fluoride

KW - 1D stripes

KW - silicon

KW - MBE

KW - RHEED

KW - XRD

KW - 3-DIMENSIONAL RHEED

KW - INITIAL-STAGES

KW - MBE GROWTH

KW - NANOPARTICLES

KW - INSULATORS

KW - SCATTERING

KW - FLUORIDE

KW - GIXD

UR - https://www.mendeley.com/catalogue/5322c94c-b02e-3979-ab3f-bcb543c22a5c/

U2 - 10.3390/surfaces4020012

DO - 10.3390/surfaces4020012

M3 - Article

VL - 4

SP - 97

EP - 105

JO - Surfaces

JF - Surfaces

SN - 2571-9637

IS - 2

ER -