Nanopatterning Si(111) surfaces as a selective surface-chemistry route

Michalak, David J.; Amy, Sandrine Rivillon; Aureau, Damien; Dai, Min; Estève, Alain; Chabal, Yves J.

doi:10.1038/nmat2611

Cited by 133 publications

(191 citation statements)

References 39 publications

Supporting

Mentioning

182

Contrasting

Order By: Relevance

“…This is logical as step edge dangling bonds are the only ones that may be susceptible to Si-Si backbond weakening. Furthermore, the atomic flatness of the surface lattice does not permit any further attacks of Si-Si bonding [28], in good agreement with our observations. For p-type silicon (111), the large density of holes helps weaken the Si-Si bond at the surface, and this allows for nucleophilic attack according to the Gerischer's mechanism [29,30].…”

Section: Resultssupporting

confidence: 91%

“…This is logical as step edge dangling bonds are the only ones that may be susceptible to Si-Si backbond weakening. Furthermore, the atomic flatness of the surface lattice does not permit any further attacks of Si-Si bonding [28], in good agreement with our observations. On the other hand, these physical rationales and processes were relatively similar for the p-type silicon (100) surfaces with some notable differences: a HF acid treated (100) surface would exhibit inherent roughening as well as a mixed population of silicon monohydride, bihydride and trihydrides [34].…”

Section: Resultssupporting

confidence: 91%

“…Hence, to describe the changes to the p-type silicon (111) surface roughness and the concurrent absence of roughening on n-type silicon, it is important to appreciate that atomically flat hydrogen-terminated (111) silicon surfaces are generally less likely to be etched or roughened due to the co-planar arrangement of atoms at the surface that renders it relatively stable. Thus, the weakening of the Si-Si backbond is deemed to be difficult due to the sterics on the surface [28]. For our case, in the first phase of the reaction, the alcohol grafting and the subsequent formation of the Si-O-C linkage on the surface would induce a polarization of the surface.…”

Section: Resultsmentioning

confidence: 95%

See 2 more Smart Citations

Influences of Doping and Crystal Orientation on Surface Roughening upon Alcohol Grafting onto Silicon Hydride

Tung

Khung

2017

Applied Sciences

View full text Add to dashboard Cite

An alcohol bearing alkyne was thermally grafted to both p-type and n-type silicon (111) and (100) substrate of comparable doping levels and surface flatness. The surface topography as well as the surface chemistry was examined via atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and water contact angle measurements. P-type silicon (111) was observed to experience roughening on the surface upon functionalization while n-type silicon (111) surfaces remained relatively unchanged. When the alcohol was grafted onto silicon (100) surface, the roughening effect was found to be even more profound for the p-type while the effects were marginal for the n-type surfaces. Both roughening effects were attributed to the differential weakening of the Si-Si backbond induced by majority carriers in p-and n-type silicon while (111) was observed to be able to resist the roughening effect better and this was explained by the notion of its denser adatom surface packing as well as the presence of surface defects.

show abstract

Section: Resultssupporting

confidence: 91%

“…This is logical as step edge dangling bonds are the only ones that may be susceptible to Si-Si backbond weakening. Furthermore, the atomic flatness of the surface lattice does not permit any further attacks of Si-Si bonding [28], in good agreement with our observations. On the other hand, these physical rationales and processes were relatively similar for the p-type silicon (100) surfaces with some notable differences: a HF acid treated (100) surface would exhibit inherent roughening as well as a mixed population of silicon monohydride, bihydride and trihydrides [34].…”

Section: Resultssupporting

confidence: 91%

Section: Resultsmentioning

confidence: 95%

See 1 more Smart Citation

Influences of Doping and Crystal Orientation on Surface Roughening upon Alcohol Grafting onto Silicon Hydride

Tung

Khung

2017

Applied Sciences

View full text Add to dashboard Cite

show abstract

“…Longo et al studied an alternative approach based on work involving the grafting of OH-containing compounds by Michalak. [24][25][26] The initial process was based on a methodology to covalently bond an alcohol to an Si-H surface and was extended to phosphonic acids. This study differed by attempting to reduce the amount of potentially deleterious carbon in the process which may be a problem with current carbon-based precursors.…”

mentioning

confidence: 99%

Chemical approaches for doping nanodevice architectures

et al. 2016

View full text Add to dashboard Cite

Access to the full text of the published version may require a subscription. after most spin-on-doping processes which are often difficult to remove. In-situ doping of nanostructures is especially common for bottom-up grown nanostructures but problems associated with concentration gradients and morphology changes are commonly experienced. Monolayer doping (MLD) has been shown to satisfy the requirements for extended defect-free, conformal and controllable doping on many materials ranging from traditional silicon and germanium devices to emerging replacement materials such as III-V compounds but challenges still remain, especially with regard to metrology and surface chemistry at such small feature sizes. This article summarises and critically assesses developments over the last number of years regarding the application of gas and solution phase techniques to dope silicon-, germanium-and III-V-based materials and nanostructures to obtain shallow diffusion depths coupled with high carrier concentrations and abrupt junctions. Rights3

show abstract

“…We also note that the peak at 790 cm -1 in the FT-IR spectrum after reaction is located in the region where various Si-OH vibrational modes have been noted in the past. 119 However, the lack of a hydroxyl feature at 3600 cm -1 is inconsistent with the assignment of the peak at 790 cm -1 as due to Si-OH.…”

Section: Ft-ir Characterization Of Si Nps Reacted With N-hexanementioning

confidence: 94%

Investigation into Effects of Instability and Reactivity of Hydride-Passivated Silicon Nanoparticles on Interband Photoluminescence

Radlinger¹

View full text Add to dashboard Cite

While silicon has long been utilized for its electronic properties, its use as an optical material has largely been limited due to the poor efficiency of interband transitions. However, discovery of visible photoluminescence (PL) from nanocrystalline silicon in 1990 triggered many ensuing research efforts to optimize PL from nanocrystalline silicon for optical applications. Currently, use of photoluminescent silicon nanoparticles (Si NPs) is commercially limited by: 1) the instability of the energy and intensity of the PL, and 2) the low quantum yield of interband PL from Si NPs.Herein, red-emitting, hydrogen-passivated silicon nanoparticles (H-Si NPs) were synthesized by thermally-induced disproportionation of a HSiCl 3 -derived (HSiO 1.5 )n polymer. The H-Si NPs produced by this method were then subjected to various chemical and physical environments to assess the long-term stability of the optical properties as a function of changing surface composition. This dissertation is intended to elucidate correlations between the reported PL instability and the observed changes in the Si NP surface chemistry over time and as a function of environment.First, the stability of the H-Si NP surface at slightly elevated temperatures towards reactivity with a simple alkane was probed. The H-Si NPs were observed by FT-IR spectroscopy to undergo partial hydrosilylation upon heating in refluxing hexane, in addition to varying degrees of surface oxidation. The unexpected reactivity of the Si surface in n-hexane supports the unstable nature of the H-Si NP surface, and furthermore implicates the presence of highly-reactive Si radicals on the surfaces of the Si NPs. We propose that reaction of alkene impurities with the Si surface radicals is largely responsible for the observed surface alkylation. However, we also present an alternate ii mechanism by which Si surface radicals could react with alkanes to result in alkylation of the surface.Next, the energy and intensity stability of the interband PL from H-Si NPs in the presence of a radical trap was probed. Upon addition of (2,2,6,6,-tetramethyl-piperidin-1-yl)oxyl (TEMPO), the energy and intensity of the interband transition was observed to change over time, dependent on the reaction conditions. First, when the reaction occurred at 4ºC with minimal light exposure, the interband transition exhibited a gradual hypsochromic shift to between 595 nm and 655 nm, versus the λ max of the original low energy emission peak at 700 nm, depending on the amount of TEMPO in the sample.Second, when the reaction proceeded at room temperature with frequent exposure to 360 nm irradiation, the original interband transition at 660 nm was quenched while a new peak at 575 nm developed. Based on all the data collected and analyzed, we assign the 595 -655 nm transition as due to interband exciton recombination from Si NPs with reduced diameters relative to the original Si NPs. We furthermore assign the 575 nm transition as due to an oxide-related defect state resulting from rapid oxidation of pho...

show abstract

Nanopatterning Si(111) surfaces as a selective surface-chemistry route

Cited by 133 publications

References 39 publications

Influences of Doping and Crystal Orientation on Surface Roughening upon Alcohol Grafting onto Silicon Hydride

Influences of Doping and Crystal Orientation on Surface Roughening upon Alcohol Grafting onto Silicon Hydride

Chemical approaches for doping nanodevice architectures

Investigation into Effects of Instability and Reactivity of Hydride-Passivated Silicon Nanoparticles on Interband Photoluminescence

Contact Info

Product

Resources

About