Facile Fabrication of Ordered Crystalline‐Semiconductor Microstructures on Compliant Substrates

Cavallo, Francesca; Turner, Kevin T.; Lagally, M. G.

doi:10.1002/adfm.201303165

Cited by 13 publications

(34 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the pursuit of new physical properties, Group IV NMs have been strained in a controlled manner, among others, to modify the band structure or band offsets [11,12], to change the strain symmetry [13], or to create improved two-dimensional electron gases [14,15]. In the pursuit of nanoarchitectures or new devices, Group IV NMs have been rolled into tubes [10,[16][17][18] or supported channels [19]; or bonded to flexible supports [7,[20][21][22][23][24] or curved surfaces [25] for electronic-and optoelectronic-device applications.…”

Section: Introductionmentioning

confidence: 99%

Silicon nanomembranes as a means to evaluate stress evolution in deposited thin films

Clausen¹,

Paskiewicz²,

Sadeghirad³

et al. 2014

Extreme Mechanics Letters

Self Cite

View full text Add to dashboard Cite

Thin-film deposition on ultra-thin substrates poses unique challenges because of the potential for a dynamic response to the film stress during deposition. While theoretical studies have investigated film stress related changes in the substrate, little has been done to learn how stress might evolve in a film growing on a compliant substrate. We use silicon nanomembranes (SiNMs), extremely thin sheets of single-crystalline Si, as a substrate for the growth of amorphous SiN x to begin to address this question. Nanomembranes are released from a silicon-oninsulator wafer with selective etching, transferred over a hole etched into a Si wafer, and bonded to the edges of the hole. The nanomembrane window provides the substrate for SiN x deposition and a platform, using Raman spectroscopy, for measurements of the evolving strain in the nanomembrane. From the strain in the nanomembrane, the film stress can be inferred from the required balance of forces in the film/substrate system. We observe that the strain in the tethered 2 NM increases as the NM is made thinner while the intrinsic steady-state stress in the deposited film is reduced.

show abstract

Section: Introductionmentioning

confidence: 99%

Silicon nanomembranes as a means to evaluate stress evolution in deposited thin films

Clausen¹,

Paskiewicz²,

Sadeghirad³

et al. 2014

Extreme Mechanics Letters

Self Cite

View full text Add to dashboard Cite

show abstract

“…30 In these samples, the open area between the NM and the supporting wrinkled PDMS substrate is on the order of a few hundred nanometers, that is, much smaller than Figure 3. Confocal fluorescence microscope images showing strong guidance of neuronal outgrowths by buckledelaminated channels, while excluding the neuronal cell body (indicated by arrows).…”

Section: Resultsmentioning

confidence: 88%

“…The fabrication of 3D structures on hard/soft substrates and the mechanics and chemistry underlying the process are detailed in our earlier work. 30 In brief, a SiNM is transferred onto a PDMS thin substrate and patterned. The PDMS support is then swollen in an organic solvent.…”

Section: Resultsmentioning

confidence: 99%

“…The origin of this mechanical instability is discussed in our earlier work. 30 Figure 2c illustrates the behavior of out-of-plane dimensions (i.e., amplitude versus length) of wrinkled ARTICLE www.acsnano.org C structures as a function of applied strain. The two data sets in Figure 2c correspond to 17 and 55 nm thick NM/PDMS systems, treated with several solvents for 20 h (although no further swelling of the PDMS substrate occurs after 2 h 30 ).…”

Section: Resultsmentioning

confidence: 99%

“…Each solvent produces a different degree of swelling of the PDMS and hence a different value of strain applied to the SiNM during deswelling. 30 Neurite Guidance. We access neurite guidance using a primary mouse cortical cell culture, a commonly used in vitro model.…”

Section: Resultsmentioning

confidence: 99%

See 2 more Smart Citations

Neurite Guidance and Three-Dimensional ConfinementviaCompliant Semiconductor Scaffolds

et al. 2014

Self Cite

View full text Add to dashboard Cite

Neurons are often cultured in vitro on a flat, open, and rigid substrate, a platform that does not reflect well the native microenvironment of the brain. To address this concern, we have developed a culturing platform containing arrays of microchannels, formed in a crystalline-silicon nanomembrane (NM) resting on polydimethylsiloxane; this platform will additionally enable active sensing and stimulation at the local scale, via devices fabricated in the silicon. The mechanical properties of the composite Si/compliant substrate nanomaterial approximate those of neural tissue. The microchannels, created in the NM by strain engineering, demonstrate strong guidance of neurite outgrowth. Using plasma techniques, we developed a means to coat just the inside surface of these channels with an adhesion promoter (poly-d-lysine). For NM channels with openings larger than the cross-sectional area of a single axon, strong physical confinement and guidance of axons through the channels are observed. Imaging of axons that grow in channels with openings that approximate the size of an axon suggests that a tight seal exists between the cell membrane and the inner surface of the channel, mimicking a myelin sheath. Such a tight seal of the cell membrane with the channel surface would make this platform an attractive candidate for future neuronal repair. Results of measurements of impedance and photoluminescence of bare NM channels are comparable to those on a flat NM, demonstrating electrical and optical modalities of our platform and suggesting that this scaffold can be expanded for active sensing and monitoring of neuron cellular processes in conditions in which they exist naturally.

show abstract

Nanocatalyst Design for Long‐Term Operation of Proton/Anion Exchange Membrane Water Electrolysis

Jin

Ruqia

Park

et al. 2020

Advanced Energy Materials

119

View full text Add to dashboard Cite

Long‐term catalyst stability is essential for the commercialization of hydrogen generation by electrocatalytic water‐splitting. Current research, however, mainly focuses on improving electrode activity of the hydrogen evolution reaction (HER) at the cathode and oxygen evolution reaction (OER) at the anode of electrolyzers, although the maintenance of long‐term performance poses a bigger challenge. To shift the focus of research to the issue of catalyst stability, this review describes the mechanism of HER/OER catalyst degradation based on catalyst dissolution and agglomeration, and summarizes representative catalyst designs for achieving stable catalysts in long‐term water electrolysis operation. Additionally, various strategies toward the improvement of HER/OER stability are evaluated, and potential effective guidelines for the design of stable catalysts are suggested.

show abstract

Facile Fabrication of Ordered Crystalline‐Semiconductor Microstructures on Compliant Substrates

Cited by 13 publications

References 32 publications

Silicon nanomembranes as a means to evaluate stress evolution in deposited thin films

Silicon nanomembranes as a means to evaluate stress evolution in deposited thin films

Neurite Guidance and Three-Dimensional ConfinementviaCompliant Semiconductor Scaffolds

Nanocatalyst Design for Long‐Term Operation of Proton/Anion Exchange Membrane Water Electrolysis

Contact Info

Product

Resources

About