TY - JOUR
T1 - Large Dense Periodic Arrays of Vertically Aligned Sharp Silicon Nanocones
AU - Jonker, Dirk
AU - Berenschot, Erwin J.W.
AU - Tas, Niels R.
AU - Tiggelaar, Roald M.
AU - van Houselt, Arie
AU - Gardeniers, Han J.G.E.
N1 - Funding Information:
Special thanks go out to Meint de Boer (MESA+ NanoLab) for discussion about the CM-ICP RIE etching of SiNWs in argon, Henk van Wolferen (MESA+ NanoLab) for TEM sample preparation, Rico Keim (MESA+ NanoLab) for TEM sample analysis, Mark Smithers (MESA+ NanoLab) for HR-SEM analysis, and Bjorn Borgelink (Mesoscale Chemical Systems) for insightful discussions on silicon oxidation. This work was supported by the Netherlands Center for Multiscale Catalytic Energy Conversion (MCEC), an NWO Gravitation program funded by the Ministry of Education, Culture and Science of the government of the Netherlands.
Funding Information:
Special thanks go out to Meint de Boer (MESA+ NanoLab) for discussion about the CM-ICP RIE etching of SiNWs in argon, Henk van Wolferen (MESA+ NanoLab) for TEM sample preparation, Rico Keim (MESA+ NanoLab) for TEM sample analysis, Mark Smithers (MESA+ NanoLab) for HR-SEM analysis, and Bjorn Borgelink (Mesoscale Chemical Systems) for insightful discussions on silicon oxidation. This work was supported by the Netherlands Center for Multiscale Catalytic Energy Conversion (MCEC), an NWO Gravitation program funded by the Ministry of Education, Culture and Science of the government of the Netherlands.
Funding Information:
This work was supported by the Netherlands center for Multiscale Catalytic Energy Conversion (MCEC), an NWO program funded by the Ministry of Education, Culture and Science of the government of the Netherlands. This work has received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska‐Curie Grant agreement No. 801359.
Publisher Copyright:
© 2022, The Author(s).
Financial transaction number:
2500026600
PY - 2022/10/16
Y1 - 2022/10/16
N2 - Convex cylindrical silicon nanostructures, also referred to as silicon nanocones, find their value in many applications ranging from photovoltaics to nanofluidics, nanophotonics, and nanoelectronic applications. To fabricate silicon nanocones, both bottom-up and top-down methods can be used. The top-down method presented in this work relies on pre-shaping of silicon nanowires by ion beam etching followed by self-limited thermal oxidation. The combination of pre-shaping and oxidation obtains high-density, high aspect ratio, periodic, and vertically aligned sharp single-crystalline silicon nanocones at the wafer-scale. The homogeneity of the presented nanocones is unprecedented and may give rise to applications where numerical modeling and experiments are combined without assumptions about morphology of the nanocone. The silicon nanocones are organized in a square periodic lattice, with 250 nm pitch giving arrays containing 1.6 billion structures per square centimeter. The nanocone arrays were several mm2 in size and located centimeters apart across a 100-mm-diameter single-crystalline silicon (100) substrate. For single nanocones, tip radii of curvature < 3 nm were measured. The silicon nanocones were vertically aligned, baring a height variation of < 5 nm (< 1%) for seven adjacent nanocones, whereas the height inhomogeneity is < 80 nm (< 16%) across the full wafer scale. The height inhomogeneity can be explained by inhomogeneity present in the radii of the initial columnar polymer mask. The presented method might also be applicable to silicon micro- and nanowires derived through other top-down or bottom-up methods because of the combination of ion beam etching pre-shaping and thermal oxidation sharpening. Graphic abstract: A novel method is presented where argon ion beam etching and thermal oxidation sharpening are combined to tailor a high-density single-crystalline silicon nanowire array into a vertically aligned single-crystalline silicon nanocones array with < 3 nm apex radius of curvature tips, at the wafer scale. [Figure not available: see fulltext.]
AB - Convex cylindrical silicon nanostructures, also referred to as silicon nanocones, find their value in many applications ranging from photovoltaics to nanofluidics, nanophotonics, and nanoelectronic applications. To fabricate silicon nanocones, both bottom-up and top-down methods can be used. The top-down method presented in this work relies on pre-shaping of silicon nanowires by ion beam etching followed by self-limited thermal oxidation. The combination of pre-shaping and oxidation obtains high-density, high aspect ratio, periodic, and vertically aligned sharp single-crystalline silicon nanocones at the wafer-scale. The homogeneity of the presented nanocones is unprecedented and may give rise to applications where numerical modeling and experiments are combined without assumptions about morphology of the nanocone. The silicon nanocones are organized in a square periodic lattice, with 250 nm pitch giving arrays containing 1.6 billion structures per square centimeter. The nanocone arrays were several mm2 in size and located centimeters apart across a 100-mm-diameter single-crystalline silicon (100) substrate. For single nanocones, tip radii of curvature < 3 nm were measured. The silicon nanocones were vertically aligned, baring a height variation of < 5 nm (< 1%) for seven adjacent nanocones, whereas the height inhomogeneity is < 80 nm (< 16%) across the full wafer scale. The height inhomogeneity can be explained by inhomogeneity present in the radii of the initial columnar polymer mask. The presented method might also be applicable to silicon micro- and nanowires derived through other top-down or bottom-up methods because of the combination of ion beam etching pre-shaping and thermal oxidation sharpening. Graphic abstract: A novel method is presented where argon ion beam etching and thermal oxidation sharpening are combined to tailor a high-density single-crystalline silicon nanowire array into a vertically aligned single-crystalline silicon nanocones array with < 3 nm apex radius of curvature tips, at the wafer scale. [Figure not available: see fulltext.]
KW - Ion beam etching
KW - Nanowires
KW - Periodic silicon nanocone
KW - Self-limited oxide growth
KW - Thermal oxidation
KW - Vertical alignment
UR - http://www.scopus.com/inward/record.url?scp=85139842482&partnerID=8YFLogxK
U2 - 10.1186/s11671-022-03735-y
DO - 10.1186/s11671-022-03735-y
M3 - Article
AN - SCOPUS:85139842482
SN - 1931-7573
VL - 17
JO - Nanoscale research letters
JF - Nanoscale research letters
IS - 1
M1 - 100
ER -