Nucleation and growth of thin films

Venables, J. A.; Spiller, G. D. T.; Hanbücken, M.

doi:10.1088/0034-4885/47/4/002

Cited by 2,552 publications

(1,557 citation statements)

References 221 publications

Supporting

Mentioning

1,431

Contrasting

Unclassified

Order By: Relevance

“…The values chosen for τ N and D are discussed below. In the early stage and complete condensation regime considered here, n 1 linearly increases with t. 24 To verify this condition, we use realistic parameters to plot the molecular concentration in the middle of the aperture n 1 (0, 0, t) and at the edge n 1 (-a/2, 0, t) as a function of t ≤ τ N for different a (see Fig. S3 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 12 iso-ߣ ே lines precisely follow the contour lines of ܰ ഥ .…”

mentioning

confidence: 77%

Arrays of Pentacene Single Crystals by Stencil Evaporation

Fesenko

Flauraud

Xie

et al. 2016

Crystal Growth & Design

View full text Add to dashboard Cite

In order to realize high-performance organic thin-film transistors (TFT), two parameters of the organic semiconducting layer are desired: single crystallinity for high mobility, and patterning for low off currents. High-quality single crystals can be fabricated using vapor techniques such as physical vapor transport (PVT) but they require high temperatures close to thermodynamic 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 2 equilibrium, for example, 240°C for pentacene. Such high temperatures are not ideal for TFT fabrication on plastic substrates and limit the use of PVT in flexible electronics applications.In this work arrays of pentacene single crystals were directly deposited at low temperature of 40°C by vacuum thermal evaporation through micro-fabricated stencil masks (stencil lithography). By decreasing the stencil aperture size down to 1 µm x 1 µm, we were able to limit the nucleation area until only one grain per aperture is nucleated and grown. We studied systematically scaling effects for large singe crystal growth and discuss details of the growth morphology. We found for instance that the formed pentacene crystals are one monolayer thick and the crystal area is much larger than the aperture size. This can be explained by the diffusion of adsorbed molecules on the surface laterally under the shadow mask, where they are protected from other impinging molecules. The diffusion away from the impinging area under the aperture affects the nucleation density inside this area and was used to calculate the diffusion length to nucleation λ N = 0.66 ± 0.11 µm of pentacene on SiO 2 at 40°C. Our diffusion-driven growth of organic single crystals by stencil lithography is a direct method to grow patterned arrays of single crystalline organic thin-film semiconductor layers.

show abstract

mentioning

confidence: 77%

Arrays of Pentacene Single Crystals by Stencil Evaporation

Fesenko

Flauraud

Xie

et al. 2016

Crystal Growth & Design

View full text Add to dashboard Cite

show abstract

“…Moreover, it is experimentally proven [185–187] that ultrathin films with only dozens of layers are thermodynamically unstable unless they inherently constitute a part of three-dimensional structures (e.g. a substrate with a matching lattice).…”

Section: Disorders In Graphene Structurementioning

confidence: 99%

Structure of graphene and its disorders: a review

Gao

Lee

et al. 2018

Science and Technology of Advanced Materials

487

187

View full text Add to dashboard Cite

Monolayer graphene exhibits extraordinary properties owing to the unique, regular arrangement of atoms in it. However, graphene is usually modified for specific applications, which introduces disorder. This article presents details of graphene structure, including sp2 hybridization, critical parameters of the unit cell, formation of σ and π bonds, electronic band structure, edge orientations, and the number and stacking order of graphene layers. We also discuss topics related to the creation and configuration of disorders in graphene, such as corrugations, topological defects, vacancies, adatoms and sp3-defects. The effects of these disorders on the electrical, thermal, chemical and mechanical properties of graphene are analyzed subsequently. Finally, we review previous work on the modulation of structural defects in graphene for specific applications.

show abstract

“…Both processes are expected to be associated with the formation of 'craters' or even the openings penetrating through the oxide toward the substrate surface [29,33,34]. Therefore, the rate constants K 3 and K 35 should be orders of magnitude lower than that given by the effective Ga diffusivities (σ 3 D 3 and σ 35 D 3 , with σ as the corresponding capture coefficients [35][36][37]). …”

Section: The Modelmentioning

confidence: 99%

“…Within the frame of the irreversible growth model, that is, with neglect of decay of both Ga-Ga and Ga-As surface dimers [35][36][37], the set of kinetic equations for the surface density of Ga droplets (N 3 ), parasitic GaAs islands (N 35 ) and Ga adatoms (n 3 ) can be written as Here, we assume that the kinetic growth constants are the same for differently sized surface clusters, as in [36] and [37]. The first equation shows that the number of Ga droplets increases due to the Ga-Ga dimerization, with K 3 n 3 2 as the nucleation rate in irreversible growth [37].…”

Section: The Modelmentioning

confidence: 99%

Tailoring the diameter and density of self-catalyzed GaAs nanowires on silicon

et al. 2015

View full text Add to dashboard Cite

Nanowire diameter has a dramatic effect on the absorption cross-section in the optical domain. The maximum absorption is reached for ideal nanowire morphology within a solar cell device. As a consequence, understanding how to tailor the nanowire diameter and density is extremely important for high-efficient nanowire-based solar cells. In this work, we investigate mastering the diameter and density of self-catalyzed GaAs nanowires on Si(111) substrates by growth conditions using the self-assembly of Ga droplets. We introduce a new paradigm of the characteristic nucleation time controlled by group III flux and temperature that determine diameter and length distributions of GaAs nanowires. This insight into the growth mechanism is then used to grow nanowire forests with a completely tailored diameter-density distribution. We also show how the reflectivity of nanowire arrays can be minimized in this way. In general, this work opens new possibilities for the cost-effective and controlled fabrication of the ensembles of self-catalyzed III-V nanowires for different applications, in particular in next-generation photovoltaic devices.S Online supplementary data available from stacks.iop.org/NANO/26/105603/mmedia

show abstract

Nucleation and growth of thin films

Cited by 2,552 publications

References 221 publications

Arrays of Pentacene Single Crystals by Stencil Evaporation

Arrays of Pentacene Single Crystals by Stencil Evaporation

Structure of graphene and its disorders: a review

Tailoring the diameter and density of self-catalyzed GaAs nanowires on silicon

Contact Info

Product

Resources

About