TEM sample preparation of lithographically patterned permalloy nanostructures on silicon nitride membranes

• Joshua Williams,
• Michael I. Faley,
• Joseph Vimal Vas,
• Peng-Han Lu and
• Rafal E. Dunin-Borkowski

Beilstein J. Nanotechnol. 2024, 15, 1–12, doi:10.3762/bjnano.15.1

• KOH solution resulted in a faster etch rate but led to much stronger bubbling and roughening of the Si surface with the creation of micropyramidal hillocks [31]. The surface alignment of the Si substrates is parallel to the {100} crystallographic plane of Si, and the anisotropic KOH etching results in

Morphology-driven gas sensing by fabricated fractals: A review

• Vishal Kamathe and
• Rupali Nagar

Beilstein J. Nanotechnol. 2021, 12, 1187–1208, doi:10.3762/bjnano.12.88

• pits. The self-organization of structures was attributed to tin chloride, which led to a larger size of the pits, while copper oxide led to the formation of hillocks in the film. The D values of the samples were in the range of 2.00–2.24. For the Sn/Cu = 6 ratio, the fractal dimension was 2.0, and the

• sample, exhibiting a combination of hillocks and pores, showed the maximum sensitivity (S = 0.29) towards NO2. Another study reported dendritic nanowires (DNWs) of SnO2 on a gold-coated silicon substrate for NO2 sensing [66]. The samples were prepared by evaporation–condensation. Figure 6a and Figure 6b

Direct growth of few-layer graphene on AlN-based resonators for high-sensitivity gravimetric biosensors

• Jimena Olivares,
• Teona Mirea,
• Lorena Gordillo-Dagallier,
• Bruno Marco,
• José Miguel Escolano,
• Marta Clement and
• Enrique Iborra

Beilstein J. Nanotechnol. 2019, 10, 975–984, doi:10.3762/bjnano.10.98

• in contact mode; AFM images are shown in Figure 1. Compared with the surface of the bare Ni surface (Figure 1a), high heating rates induce the partial dewetting of the Ni layer (Figure 1b), which displays a non-uniform thickness distribution, combining areas with hillocks and areas with voids

• apparently exposing the Mo underlayer. Ni films subjected to lower heating rates (Figure 1c) exhibit smoother surfaces with the presence of distant large pores. It is worth noting that micro-Raman spectroscopy measurements revealed that the quality of the graphene layer is roughly the same in the hillocks

Identifying the nature of surface chemical modification for directed self-assembly of block copolymers

• Laura Evangelio,
• Federico Gramazio,
• Matteo Lorenzoni,
• Michaela Gorgoi,
• Francisco Miguel Espinosa,
• Ricardo García,
• Francesc Pérez-Murano and
• Jordi Fraxedas

Beilstein J. Nanotechnol. 2017, 8, 1972–1981, doi:10.3762/bjnano.8.198

• made with PDMS and coated with 100 nm gold film evaporated in high vacuum. The stamp surface presents parallel hillocks 320 nm wide and spaced 740 nm. The height of the protrusions is 40 nm. To transfer the patterns from the stamp to the substrate a 35–40 V bias voltage (sample positive) for a time

Annealing-induced recovery of indents in thin Au(Fe) bilayer films

• Anna Kosinova,
• Ruth Schwaiger,
• Leonid Klinger and
• Eugen Rabkin

Beilstein J. Nanotechnol. 2016, 7, 2088–2099, doi:10.3762/bjnano.7.199

• in a forming gas atmosphere. While the onset of solid-state dewetting was observed in the unperturbed regions of the film, no holes to the substrate were observed in the indented regions. Instead, the film annealing resulted in the formation of hillocks at the indent locations, followed by their

• tilt grain boundaries, and low-angle grain boundaries were present in the film. The atomic force microscopy (AFM) image of the Au(Fe) film surface (Figure 2) was taken four months after the film deposition. Hillocks with a height up to 25 nm were present on the film surface, which could be the result

• of slow stress relaxation in the as-deposited Au(Fe) bilayers at room temperature. After the first annealing for 10 min, the hillocks disappeared. AFM line profiles were used to determine the indent depth before and after annealing. The average depths of the as-produced indents were 18 and 25 nm for

Effect of tetramethylammonium hydroxide/isopropyl alcohol wet etching on geometry and surface roughness of silicon nanowires fabricated by AFM lithography

• Siti Noorhaniah Yusoh and
• Khatijah Aisha Yaacob

Beilstein J. Nanotechnol. 2016, 7, 1461–1470, doi:10.3762/bjnano.7.138

• handling and CMOS compatibility. According to Merlos et al. [16], a smooth surface, free of hillocks can be obtained by using TMAH as an etchant with a concentration greater than 25 wt %. Hutagalung and Lew [17] used 25 wt % of TMAH at 65 °C for 30 s to remove unmasked silicon layers. Then, an improvement

• %). The obtained silicon nanowires are free of hillocks or micropyramids. Both the width and gap dimensions vary based on the concentration of the added IPA. Further addition of IPA into TMAH produced wider silicon nanowires, consequently decreasing the gap between the nanowires. The unmasked silicon

• surface due to formation of hillocks. The existence of hillocks after etching is the main contribution to the rougher surface. When 10 vol % IPA was added to the TMAH solution, the density and size of hillocks becomes smaller (Figure 12b), giving rise to the decrease in the Ra value. The surface becomes

Dealloying of gold–copper alloy nanowires: From hillocks to ring-shaped nanopores

• Adrien Chauvin,
• Cyril Delacôte,
• Mohammed Boujtita,
• Benoit Angleraud,
• Junjun Ding,
• Chang-Hwan Choi,
• Pierre-Yves Tessier and
• Abdel-Aziz El Mel

Beilstein J. Nanotechnol. 2016, 7, 1361–1367, doi:10.3762/bjnano.7.127

• nodular growth triggered by the presence of surface defects created intentionally on the substrate as well as the high tilt angle between the magnetron source axis and the normal to the substrate, metal nanowires containing hillocks emerging out of the surface can be created. The approach is demonstrated

• for several metals and alloys including gold, copper, silver, gold–copper and gold–silver. We demonstrate that applying an electrochemical dealloying process to the gold–copper alloy nanowire arrays allows for transforming the hillocks into ring-like shaped nanopores. The resulting porous gold

• nanowires exhibit a very high roughness and high specific surface making of them a promising candidate for the development of SERS-based sensors. Keywords: copper; dealloying; gold; hillocks; nanoporous; Introduction Improvement in nanoscience involves fundamental evolution in the synthesis and

High sensitivity and high resolution element 3D analysis by a combined SIMS–SPM instrument

• Yves Fleming and
• Tom Wirtz

Beilstein J. Nanotechnol. 2015, 6, 1091–1099, doi:10.3762/bjnano.6.110

• flat topography changes during Cs+ bombardment and hillocks locally form at the locations of the nanoparticles. Thus, the maximum crater depth was only reached at x- and y-coordinates where no nanoparticles were found. This example and the previous examples show that the combined SIMS–AFM instrument