Vapor-solid growth of Te-rich SbTe nanowires on a template of nano-size trenches

Jeong, Jin Hwan; Park, Si Jung; An, Su Bin; Choi, Doo Jin

doi:10.1016/j.jcrysgro.2014.10.039

Cited by 5 publications

(4 citation statements)

References 24 publications

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“…Both the peak at ~140 cm −1 and the broad peak at ~120 cm −1 , which can be a convolution of the peaks expected for the E 2 g mode of Sb 2 Te 3 at ~113 cm −1 and for the A 1 mode of pure Te-Te bonds at ~125 cm −1 [54], indicate an excess of Te with respect to stoichiometric Sb 2 Te 3 . Such an excess of Te in Sb 2 Te 3 thin films and nanostructures has been reported in other studies [53,[55][56][57]. Also, there is no indication from Raman and TEM measurements of the presence of metastable Sb 2 Te 3 phases [58,59], consistently with the presently used growth temperatures [60].…”

Section: Deposition Of Sb-te Nanostructuressupporting

confidence: 80%

Fabrication of ordered Sb–Te and In–Ge–Te nanostructures by selective MOCVD

Cecchini

Martella

Lamperti

et al. 2020

J. Phys. D: Appl. Phys.

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The controlled growth of chalcogenide nanoscaled phase change material structures can be important to facilitate integration and to enable complex architectures for phase change memory and other microelectronic applications. Here, the growth of Sb-Te and In-Ge-Te alloys by metal-organic chemical vapour deposition (MOCVD) on patterned substrates featured with an array of recesses (~130 nm features width) was investigated. High selectivity, with preferential growth on a CoSi 2 metallic layer at the recess bottom with respect to the surrounding SiO 2 masking layer, was obtained, leading to a single-step fabrication of arrays of high-aspect-ratio chalcogenide nanostructures. The growth selectivity, as well as the morphology, composition and microstructure of the grown nanostructures, as a function of the different MOCVD process parameters, were investigated by scanning electron microscopy, transmission electron microscopy, energy dispersive x-ray spectroscopy, Raman spectroscopy and Fourier transformed infrared spectroscopy. Thanks to the chosen substrates, the synthesized nanostructures were also directly electrically accessible, as proved by conductiveatomic force microscopy.

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Section: Deposition Of Sb-te Nanostructuressupporting

confidence: 80%

Fabrication of ordered Sb–Te and In–Ge–Te nanostructures by selective MOCVD

Cecchini

Martella

Lamperti

et al. 2020

J. Phys. D: Appl. Phys.

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“…Also the peak at ≈125 cm −1 , visible after cleaning, has been related to pure Te bonds, namely to the A 1 modes . The presence of pure Te bonds could be related to Te precipitation, due to an excess of this element with respect to the stable Sb 2 Te 3 stoichiometric composition, as observed in thermally evaporated Sb 2 Te 3 films and in Sb 2 Te 3 NWs grown by a vapor–solid method in nanosized templates . Surface precipitation of Te has also been observed by Raman spectroscopy in Sb 2 Te 3 deposited by physical vapor transport .…”

Section: Resultsmentioning

confidence: 78%

“…The growth of ordered arrays of nanocrystals of different chalcogenide alloys, including Sb 2 Te 3 , by selective MOCVD growth has been demonstrated on low aspect‐ratio lithographically patterned (≈100 nm size) templates and on substrates locally treated by oxygen plasma, as well as using Au nanodeposits as catalyzers exploiting the vapor–liquid–solid mechanism . For what concerns high‐aspect‐ratio chalcogenide nanostructures, the growth of Te‐rich Sb 2 Te 3 NWs exploiting the vapor–solid mechanism on substrates patterned with pores of diameter ≈50 nm and height ≈100 nm has been explored . Clearly, further downscaling of the chalcogenide NPs/NWs size and higher arrays densities should be demonstrated in order for selective bottom‐up (MO)CVD methods to replace the processes presently used in the fabrication of, e.g., state‐of‐the‐art PCM cells, and enable the realization of the next generation of thermoelectric and spintronic devices.…”

Section: Introductionmentioning

confidence: 99%

High‐Density Sb₂Te₃ Nanopillars Arrays by Templated, Bottom‐Up MOCVD Growth

Cecchini

Gajjela

Martella

et al. 2019

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Sb2Te3 exhibits several technologically relevant properties, such as high thermoelectric efficiency, topological insulator character, and phase change memory behavior. Improved performances are observed and novel effects are predicted for this and other chalcogenide alloys when synthetized in the form of high‐aspect‐ratio nanostructures. The ability to grow chalcogenide nanowires and nanopillars (NPs) with high crystal quality in a controlled fashion, in terms of their size and position, can boost the realization of novel thermoelectric, spintronic, and memory devices. Here, it is shown that highly dense arrays of ultrascaled Sb2Te3 NPs can be grown by metal organic chemical vapor deposition (MOCVD) on patterned substrates. In particular, crystalline Sb2Te3 NPs with a diameter of 20 nm and a height of 200 nm are obtained in Au‐functionalized, anodized aluminum oxide (AAO) templates with a pore density of ≈5 × 1010 cm−2. Also, MOCVD growth of Sb2Te3 can be followed either by mechanical polishing and chemical etching to produce Sb2Te3 NPs arrays with planar surfaces or by chemical dissolution of the AAO templates to obtain freestanding Sb2Te3 NPs forests. The illustrated growth method can be further scaled to smaller pore sizes and employed for other MOCVD‐grown chalcogenide alloys and patterned substrates.

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“…At 280 1C, the inter-planar spacing of 3.01 Å (0.21% error) and 3.48 Å (0.84% error) correspond to the (200) plane and (111) plane respectively of Ge 2 Sb 2 Te 5 NaCl-type cubic phase having a lattice parameter of 6.001 Å [17]. In the case of 260 1C, the inter-planar spacing of 3.13 Å (0.32% error), 2.64 Å (0.74% error), and 1.78 Å (0.76% error) correspond to the (015) plane and (018) plane and (205) plane of Sb 2 Te 3 rhombohedral phase having lattice parameters of 4.26 Å and 29.9 Å, respectively [18]. The orientations of crystal growth shown in the inset of these figures are the fast Fourier transform (FFT) images obtained from HRTEM.…”

Section: Resultsmentioning

confidence: 96%